ISSN
1346-7328
国 総 研 資 料 第 360号
平 成 19年2月
ISSN
0386-5878
土 研 資 料 第 4040号
平 成 19年
2月

国土技術政策総合研究所資料
Technical Note of National Institute for Land and Infrastructure Management
No. 360
February 2007

土

木

研

究

所

資

料

Technical Note of Public Works Research InstituteNo. 4040
February 2007

第10回日独排水及びスラッジ処理についてのワークショップ会議録
PROCEEDINGS OF THE 10TH JAPANESE-GERMAN WORKSHOPON WASTE WATER AND SLUDGE TREATMENT

平成18年10月9日～13日
ドイツ連邦共和国 ベルリン
ホテルコートヤードマリオット
9-13 October, 2006
Hotel Courtyard Marriott,
Berlin, Federal Republic of Germany

国土交通省

国土技術政策総合研究所

National Institute for Land and Infrastructure Management
Ministry of Land, Infrastructure and Transport, Japan

独 立 行 政 法 人

土 木 研 究 所

Incorporated Administrative Agency
Public Works Research InstituteCopyright © (2007) by N.I.L.I.M. and P.W.R.I.
All rights reserved. No part of this book may be reproduced by any means,nor transmitted, nor translated into a machine language without the written
permission of the Director-General of N.I.L.I.M. and the Chief Executive of
P.W.R.I.
この報告書は、国土交通省国土技術政策総合研究所所長、独立行政法人
土木研究所理事長の承認を得て刊行したものである。したがって、本報告書の全部又は一部の転載、複製は、国土交通省国土技術政策総合研究所所長、独立行政法人土木研究所理事長の文書による承認を得ずしてこれを行ってはならない。

国土技術政策総合研究所資料
第360号
平成19年2月

Technical Note of NILIM
No. 360
February 2007

土 木 研
第4040号

Technical Note of PWRI
No. 4040 February 2007

究

所 資 料
平成19年2月

第10回日独排水及びスラッジ処理についてのワークショップ会議録
国土交通省
独立行政法人

国土技術政策総合研究所
土木研究所

下水道研究部

リサイクルチーム／水質チーム

PROCEEDINGS OF THE 10TH JAPANESE-GERMAN WORKSHOPON WASTE WATER AND SLUDGE TREATMENT
Water Quality Control Department,
National Institute for Land and Infrastructure Management
Ministry of Land, Infrastructure and Transport, Japan
Recycling Team & Water Quality Team,
Incorporated Administrative Agency
Public Works Research Institute

概要
この報告書は、平成18年10月9日～13日にドイツ連邦共和国ベルリンで行われた「第10回日独排水及びスラッジ処理についてのワークショップ」における議事録及び講演資料等を取りまとめたものである。同ワークショップでは、日独の政府・自治体・研究機関
等の代表者により、下水道技術に関する両国の現状と課題について発表と意見交換が行われた。
キーワード: 下水道技術、排水処理、スラッジ処理、ワークショップ、二国間協力

Synopsis
This publication contains the proceedings of the 10th Japanese-German Workshop on Waste
Water and Sludge Treatment, which was held in Berlin, Federal Republic of Germany during
9-13 October 2006. In this Workshop, current status and subjects of wastewater control were
presented and discussed by government and municipal officials and researchers of Japan andGermany.
Key Words: wastewater control, waste water treatment, sludge treatment, workshop,
bilateral cooperative research

序文「日独排水及びスラッジ処理のワークショップ」は、昭和 49 年 10 月に日独政府間で締結された「科学技術分野における協力に関する日本国政府とドイツ連邦共和国政府との間の協定」に基
づく環境保護パネルにおいて開催が合意されたものである。昭和 51 年 6 月に設置された「日独環境保護技術パネル」の第 4 回会合の席上でドイツ側より、下水道技術について専門家による情報交換を深めるためのワークショップの開催が提案された。この提案を受けて準備が進められ、昭和 57 年 10 月に建設省土木研究所（当時）で日独ワークショップの第 1 回会議が開催された。以降、2～3 年毎にドイツと日本で交互に開催されている。
今回の第 10 回日独ワークショップは、平成 18 年 10 月 9 日から 13 日までドイツ連邦共和国ベルリンで開催され、日本側委員団は、国及び政令市からの参加者を含め合計 13 名が、ドイツ側か
らはカールスルーエ研究所の Fuhrmann プロジェクト次長をはじめとする 15 名が参加した。
論文発表及び全体討議は、9 日、10 日の両日にわたってベルリンのホテルコートヤードマリオ
ットにて行われ、「下水道システムと下水処理」、「汚泥処理と再利用」、「水処理と分散処理システ
ム」、「水管理（雨水、浸透、管渠システム）」及び「水環境と汚濁制御」の 5 セッションにおいて、対策が必要となっている課題や最新技術について、日本側は 12 論文、ドイツ側は 11 論文の発表が行われた。11 日から 13 日にかけては、Berlin-Stahnsdorf 処理場での「雑排水、屎、尿の分離型処理のための衛生概念」に関する欧州連合実証研究、Prichsenstadt 処理場における雨水滞水池のフラッシング技術、Berching にある膜処理実験装置及び再利用公園等の現地調査を行った。また、
ワークショップの最後には共同コミュニケが作成され、ワークショップが両国の研究活動に役立ってきたこと、さらにこれを継続していくことが重要であることを確認し、次回のワークショッ
プが日本で開催することが合意された。
今回の会議で得られた知見や情報は、我が国の下水道技術者にとって有益なものと思われる。
本報告書は、このような考えに基づき、ワークショップにおける発表論文と討議の内容を取りまとめたものである。報告書の冒頭にあたり、各委員及び関係各位に深く感謝するとともに、本報告書が我が国の下水道分野で活用され、下水道技術の発展に寄与することを希望する次第である。
平成 19 年 2 月
第 10 回日独排水及びスラッジ処理についてのワークショップ
日本側委員団

団長

那須

基

目

次

１．共同コミュニケ ････････････････････････････････････････････････････････････

1

２．会議の概要 ････････････････････････････････････････････････････････････････

7

2.1

開会 ･････････････････････････････････････････････････････････････････

7

2.2

セッション 1「下水道システムと下水処理」 ･･････････････････････････････

7

2.3

セッション 2「汚泥処理と再利用」 ･･････････････････････････････････････ 12

2.4

セッション 3「水処理と分散処理システム」 ･･････････････････････････････ 14

2.5

セッション 4「水管理（雨水、浸透、管渠システム）」 ････････････････････ 17

2.6

セッション 5「水環境と汚濁制御」 ･･････････････････････････････････････ 19

2.7

閉会 ･････････････････････････････････････････････････････････････････ 21

３．現地調査の概要 ････････････････････････････････････････････････････････････ 23
別添資料
別添 1

ワークショップ記者発表資料 ･････････････････････････････････････････ 25

別添 2

ワークショップ日程（英文） ･････････････････････････････････････････ 29

別添 3

ワークショップ参加者名簿（英文） ･･･････････････････････････････････ 31

別添 4

会議及び現地調査の写真 ･････････････････････････････････････････････ 35

発表資料(1) Municipal wastewater treatment in Germany - state of the art･･････････････････････ 37

Karl-Heinz Rosenwinkel, Hannover University of Technology(2) A century-long strategy for wastewater -system management in Japan; concept shifts
from the wastewater systems to the roads toward recycling society ･･････････････････ 59
国土交通省国土技術政策総合研究所

田中 修司(3) Development of a technical controlling and energy management system within the
Wupperverband - an interim report ･･･････････････････････････････････････････ 73
Bernand Wiebusch, Wupperverband(4) Economic instruments for basin-wide efficient pollution load reduction -comparison
between effluent charge and water quality trading- ･･･････････････････････････････ 95
下水道新技術推進機構

藤木 修(5) Design and operation of membrane bioreactors in Europe ･････････････････････････ 111
Johannes Pinnekamp, Aachen University of Technology(6) Japanese experience of MBR application to municipal wastewater treatment ･･････････ 133
日本下水道事業団

村上 孝雄(7) Central management of Berlin waste waters ････････････････････････････････････ 153
Carin Sieker, Berlin Waterworks

(8) Renovation of secondary treatment facility into the step-feed biological nitrogen removal
process by the effective by the effective use of the existing structure ･････････････････ 169
京都市上下水道局

林 潔彦(9) Treatment of sludge from septic tanks in municipal waste water treatment plants ･･･････ 191
Clarisse Harley, Prack Consult Ltd.
(10) Utilization of sewage sludge in Kitakyushu City of Japan ････････････････････････ 201
北九州市建設局

近藤 保光(11) Performance evaluation research on type of the sewage sludge drying using an oil bathunder diminished pressure ･･････････････････････････････････････････････････ 217
下水道新技術推進機構

怒木 茂(12) Utilization of regional biomass centered on wastewater treatment plants ･････････････ 233
土木研究所

尾崎 正明

(13) Reuse of treated waste water ･･･････････････････････････････････････････････ 249
Stefania Paris, Huber AG(14) Establishment of guidelines for the reuse of treated wastewater ････････････････････ 263
国土交通省国土技術政策総合研究所

南山 瑞彦(15) Semi-decentralized water systems for rapidly growing urban areas ･････････････････ 279
Martin Wagner, Darmstadt University of Technology(16) Semi-decentralized infrastructure in the development area of Knittlingen, Germany ････ 297
Walter Trösch, Fraunhofer Institute(17) Hydroself flushing systems for storage basins and sewers ････････････････････････ 315
Jörg Steinhardt, Steinhardt GmbH
(18) Report on the "extension of sewerage systems to everyone who needs it" project ･･････ 327
土木研究所

酒井 憲司

(19) SPREE 2011 -Successful cooperation of engineering sciences, arts, economics, andcity planning ････････････････････････････････････････････････････････････ 343
Ralf Steeg, LURI Waterssystems Ltd.
(20) Present status and estimation method of pollutant load in wet weather flow fromurban areas ･･････････････････････････････････････････････････････････････ 345
国土交通省国土技術政策総合研究所

吉田 敏章(21) Development of wet weather sewage treatment technologies and their application to a
combined sewer system improvement plan in Osaka city ･･････････････････････････ 361
大阪市都市環境局

藤田 眞(22) Fate of estrogens in sewage treatment process and effect of treated sewage on fish ･････ 381
土木研究所

小森 行也

(23) Degradability of pharmaceuticals in the aquatic environment ･･････････････････････ 397
Klaus Kümmerer, Freiburg University of Technology

１．共同コミュニケ

- 1 -

- 2 -

- 3 -

共同コミュニケ
第 10 回日独排水及びスラッジ処理についてのワークショップ
於

ホテルコートヤードマリオット（ベルリン）
2006 年 10 月 9 日～10 日

1.

第 10 回日独排水及びスラッジ処理についてのワークショップは、環境保護技術分野における日独協力の一環として、2006 年 10 月 9 日から 10 日まで、ホテルコートヤードマ
リオット（ベルリン）で開催された。

2.

日本側代表団は、国土交通省の那須基氏を団長として、以下の代表により構成された。
田中修司

国土技術政策総合研究所

吉田敏章

国土技術政策総合研究所

南山瑞彦

国土技術政策総合研究所

林

3.

潔彦

京都市

藤田

眞

大阪市

近藤

保光

北九州市

村上

孝雄

日本下水道事業団

藤木修

下水道新技術推進機構

怒木茂

下水道新技術推進機構

酒井

憲司

土木研究所

小森

行也

土木研究所

尾崎

正明

土木研究所

ドイツ側代表団は、カールスルーエ研究所プロジェクトマネジメント局の Dieter
Fuhrmann（ディーター・フアマン）教授を団長として、以下の代表により構成された。
C.ハーレー工学修士

技術コンサルタント

S.パリス博士

プラントメーカー

J.ピネカンプ教授

アーヘン工科大学

W.トロッシュ教授

フラウンホーファー研究所

J.スタインハート工学修士

プラントメーカー- 4 -R.スティーグ工学修士

技術コンサルタント

M.ワーグナー教授

ダームシュタット工科大学

K.ローゼンヴィンケル教授

ハノーバー大学

K.キューメラー教授

フライブルグ大学

B.ビーブッシュ博士

ヴッパー水組合

C.ズィーカー博士

ベルリン水道事業体

R.フラー博士

カールスルーエ研究所

オブザーバー：
H.シュミットホリックス博士

プラントメーカー

A.ベックスタイン

技術コンサルタント

4.

開会式では、那須基氏、D.フアマン教授、R.フラー博士の挨拶があった。

5.

議長は田中氏及び南山氏（国土技術政策総合研究所）、酒井氏（土木研究所）、フアマン
教授及びフラー博士（カールスルーエ研究所）並びにワーグナー教授（ダームシュタット工科大学）が務めた。

6.

日本側から 12 編、ドイツ側から 11 編の論文が発表された。議題は、「下水道システムと下水処理」（8 編）、「汚泥処理と再利用」（4 編）、「水処理と分散処理システム」（4 編）、「水管理（雨水、浸透、管渠システム）」（5 編）及び「水環境と汚濁制御」（3 編）であった。

7.

現地調査は 2006 年 10 月 11 日から 13 日まで行われる。
-ベルリン：Berlin-Stahnsdorf 下水処理場（欧州連合実証研究「雑排水、屎、尿の分離型処理のための衛生概念」）-プリヒセンスタット（ビュルツブルグ地域）：ハイドロセルフ フラッシング システムに関する発表及び訪問（スタインハート水技術システム社）-ベルヒング：フーバー社敷地における発表及び訪問

8.

両国代表団は、この種の研究開発が非常に価値あるものであることについて合意した。
また、第 11 回のワークショップを 2009 年に日本で開催することが提案された。

10.

両国代表団は、下記の相互の関心事項について共同研究の可能性を検討することに合

意した。

- 5 -

・水循環中の微量汚染物質
・エネルギー及び物質の回収を含む経済的、環境的に最適な下水道システム
・膜分離活性汚泥法を含む水の再利用
・流域管理
日本代表団
団長

那須

ドイツ代表団
基

団長

- 6 -

Dieter Fuhrmann

２．会議の概要
2.1 開会
最初に、那須下水道技術開発官、フアマンプロジェクト次長、フラープロジェクトマネージャーから開会挨拶があり、これまでのワークショップの経緯及び意義、下水道技術及び事業の現状につき、発表がなされた。また、各委員より、それぞれの専門や業務等を含めて自己紹介が行われた。
2.2 セッション１「下水道システムと下水処理」（1）ドイツにおける最新の下水処理
EU の下水指令（Wastewater Directive）では、COD、BOD 及び栄養塩類につき放流水質の年平均値に対して排出基準が定められている。ドイツではこれに加え、対象となる処理場の規模を広げた上で、最大値（qualified peak sample）に対して規制が行われており、1 万人当量以上の処理場では TN、TP の基準が設定されている。
ドイツで主に用いられている窒素除去法は、循環式硝化脱窒法や高度処理オキシデーションディッチ法である。高度処理オキシデーションディッチ法と生物学的りん除去法や返送汚泥りん除去との組み合わせが試みられており、基準を満たす結果が得られている。
また、流域統合管理の考え方が広まってきている。最近では、都市部の流域において、既存の処理場の能力を最大限活用できるように最適化して CSO を可能な限り処理場で処理することにより、下水道システム全体での排出負荷量の削減に向けた試みを指向している。そのための一例として、降雨・流出予測モデル、活性汚泥モデルによる処理場運転手法が検討されている。
下水処理に関する技術動向としては、膜処理技術の導入が挙げられ、最近は大規模な処理場への導入も進んでいる。また、返流水負荷の削減のためのアンモニア除去法（deammonification）やりん回収のための MAP 生成除去等の研究が進んでいる。汚泥からのエネルギー回収や肥料減量化についてはさらに検討が必要である。
【討議概要】
日本側より、ドイツで研究されているアンモニア除去法と anammox 法との違い、また実際の適用にあたっての馴致方法について質問があった。研究されているアンモニア除去法は生物膜法であり、汚泥日令で制御する anammox 法とは異なること、そして、馴致については重要な研究課題であるとの回答があった。また、ドイツ側より、汚泥の緑農地利用に関し、栄養塩類、化学物質による地下水汚染を考慮すべきとの指摘がなされた。
（2）下水道ビジョン 2100
21 世紀になり、さまざまな変化が押し寄せて来ている。気候変動や原油価格の高騰、頻発する洪水と渇水、ヒートアイランド、出生率の低下など自然の変化と社会的な変化が同時に起こり、下水道を取り巻く背景が変化するともに、下水道そのものが役割を変化させなければならなくなった。このため、政府は今後 100 年間を見つめて、下水道を静脈系の施設から、動脈系の役割を含む施設へとその役割を転換させ、従来の下水道ではなく「循環のみち」として新たに再定義を行った。循環のみちを実現するために、①「水のみち」の創出、②「資源のみち」の創出、③「施設再生」の実現を図ることとした。水のみちを実現するため、①雨水・再生水・湧水の 100%活用、②活用の視点からの施設配置、③活用に繋がる施設構造を実現し、資源のみちを実現するための施策展開上の考え方として①処理場のエネルギ
ー100%自立、②新エネルギー等活用のトップランナーとなる、③地域へのエネルギー・資源の積極供給- 7 -を行うなどの政策を実施することになる。また施設再生では、①「発生対応型」から「予防保全型」へ転換を図り、②社会ニーズに対応した機能の高度化をはかり、③計画の一体化による事業マネージメン
トをおこなうことになる。
【討議概要】
サテライト処理場からの処理水の再利用水の供給は具体的にはどのようなところを考えているのかという質問があり、トイレの洗浄水、都市内のせせらぎの回復などであるとの回答がなされた。さらに、ごみや木屑などと汚泥を混合してエネルギーを得る方法は、どのような手法によるのか、焼却による発電か、それとも消化によりバイオマスガスを得る方法かという質問に対しては、両方あるが、土木研究所では、爆砕処理を行い、セルロースを砕き、消化しやすくする方法を研究しており、後ほど日本側の委員である尾崎委員より、この詳しい説明を行う予定であるとの回答がなされた。
（3）ヴッパー水組合における下水処理場の運転管理システムとエネルギー管理システムの開発
ヴッパー水組合は、ヴッパー川流域の河川、上水及び下水道施設の管理組合である。ヴッパー水組合
は、集中情報処理システムの更新のためのプロジェクトに 2004 年から着手しており、2007 年の完成を目指している。新システムは、下水処理場、管渠、雨水調整池、水質及び管理運営に関するデータを総合的に同時処理する管理システムの構築を目指しており、多くの職員が容易に接続、利用できるシステ
ムである。また、運用に当たっては、管理に必要なデータ分析ができ、管理レポート作成機能も併せ持たせている。プロジェクトは 3 段階に分けて進められており、2006 年 9 月現在、現状分析、システム仕様の決定、予算提案書の入手、入札、契約までの第 2 段階まで進んでいる。報告書については、月報、季報、年報作成機能を持たせ、水、汚泥処理の管理データ、労働時間管理、営業的データなどの情報も取り込むことにしている。ヴッパー水組合は、ドイツ全国のベンチマーキングプロジェクトにも参画し、他の管理会社と共に下水処理場のベンチマーク管理手法の開発を行っている。理想的管理指標に対して、実際との乖離部分をデータファイリング、評価システムと縮小化するための Plan、Do、See サイクルによって最適化管理を目指す。
一方、ヴッパー水組合は、エネルギー管理システムの開発も行っている。処理場等で使用する電力は、水力発電等の自家発電電力以外の電力を電力会社に頼っている。昨今の燃料市況が悪化する中で、電力自由化によるシステムを利用して、安価な電力の調達はもちろん、電力会社の送電網を借り受け、水力及び焼却による自家発電電力を自社の他の施設へ送電し、自家消費する道も検討している。同時に、現在の電力料金削減のため、電力のピークカットを行うことで「電力消費時間（Duration of use）」を引き上げる手法などを取り入れている。また、二酸化炭素削減を目指して、太陽光発電、風力発電などの再生可能エネルギーの導入も計画している。
【討議概要】
電力のピークカットの方法はどんな方法をとっているかとの質問がなされ、「リスキー」な手法であるが、可能な限りポンプ運転などを一時的に停止するなどの方法をとっているとの回答がなされた。
（4）流域における効率的な汚濁負荷削減のための経済的実施策～排水賦課金と水質取引の比較～
2005 年、日本では下水道法が改正され、閉鎖性水域の富栄養化による水質汚濁を防止する目的で、下水処理場排出水中の窒素、りん含有量について、移転可能な削減目標量という概念が導入された。このような制度の導入によって、米国の幾つかの流域で成功を収めつつある水質取引制度と同様の効果が期待されている。一方、ドイツをはじめとする欧州諸国では、排水課徴金とこれを原資とする補助金という経済的手法（排水課徴金／補助金制度）が広く導入・定着している。
簡単な数学的モデルによって、効率性、衡平性、地域条件の反映という観点から、両者の制度の持つ特徴について理論的な比較論考が行われた。予め汚濁負荷量の削減目標が与えられた場合、水質取引制- 8 -度と排水課徴金／補助金制度は、与えられた目標を達成するにあたって、流域全体としての効率性を最大化する、即ち流域全体のコストの総和を最小化するという点において、等価であることが示される。
汚濁負荷削減の目標量が所与の場合には、水質取引では、その目標量にあわせて排出負荷の許容量を設定すればよいので、容易に制度設計を行うことが可能であるのに対して、排水課徴金／補助金制度では、目標量から課徴金の税率と補助率を決めることが容易でないという問題がある。他方において、それぞれの下水処理場の負担について衡平が保ち易い点や、地域ごとの細かな条件が反映されやすいという点
では、排水課徴金／補助金制度の方が水質取引制度より優れていると考えられる。
【討議概要】
ドイツ側から、排水課徴金制度では、当初予定されていたより負荷量が少ない場合には、課徴金の払い戻しをすることができ、そのことが良好な処理水質を保とうとするインセンティブになっているという紹介があった。
さらに、ドイツ側から、ドイツで採用されている排水課徴金／補助金制度では、補助金の使途等について政府の役割が大きいのに対して、水質取引制度では政府の役割が小さいという指摘があった。これに対して、発表者からは、近年の日本においては、一般に政府が多くのことを引き受けるという考え方が国民に受け入れられにくい状況にある旨の説明があった。これに関連して、ドイツ側から、排水課徴金を原資とする補助金は、例えば活性炭処理や膜分離活性汚泥法の普及促進においては重要であるとの紹介があった。
水質取引制度では、流域全体として最も効率的な方法が見出されるのかとのドイツ側からの質問に対して、発表者からは、理論的にはそのとおりであるが、完全自由取引ではホットスポットと呼ぶ局地的な汚濁発生の恐れがあるため、法改正においては流総計画の枠組みのなかで運用する仕組みとされたものであるとの説明が行われた。
ドイツ側から、水質取引における、ノンポイント汚濁源や下水道を通じての間接的な汚濁排出者の扱いについて質問があった。発表者から、日本では下水処理場のみが取引に参加できるが、米国ではノンポイント汚濁発生者も取引に参加できるスキームを構築している例があること、また、下水道法の規定によれば、理論的には、下水道使用料制度を適切に設計することによって、間接的な汚濁排出者にも負荷削減の経済的インセンティブを与え得るとの回答が行われた。
（5）ヨーロッパにおける膜分離活性汚泥法（MBR）の設計と運転
MBR の特性を既往の活性汚泥法と比較しながら整理し、ドイツでの普及状況、その背景につき発表された。MBR は、処理水質は SS でゼロであり生物学的水質としても水浴可能なものとなっている等のメリットを有するが、エネルギー消費量が大きいというデメリットもある。現在のところドイツ国内の公共下水道に関しては 12 処理場で MBR が運転されており、4 処理場にて建設又は設計中である。
一方、産業排水の処理施設については、繊維工業等でより多くの適用があり、水の再利用と関連して導入されるのが典型的である。
また、ヨーロッパの処理場における MBR の設計及び運転等についてアンケート調査が実施され情報がとりまとめられた。17 処理場のデータが得られ、処理水量規模、前処理の有無や滞留時間等の運転条件が整理され現況が明らかとなった。
最後に、生物学的プロセス、膜、処理効率及び全体プロセス毎に調査トピックが整理され、技術開発の進展によるコスト低減の傾向及び展望が示された。
（6）日本における下水処理への MBR 導入
日本においても最近、膜分離活性汚泥法の都市下水処理への適用が開始され、現時点で 4 箇所の膜分
離活性汚泥法施設が稼動中であり、さらに建設中及び計画中の施設は 10 か所程度にのぼっている。日- 9 -本における膜分離活性汚泥法の設計にあたっては、現在のところ、小規模施設への適用が中心と考え、流量調整槽を設けている。本論文においては、日本の膜分離活性汚泥法の設計の考え方を紹介した。
また、膜分離活性汚泥法に関する日本下水道事業団の最近の研究成果を紹介した。まず、臭気発生は、
標準活性汚泥法よりもかなり少ないことが明らかになった。また、ウィルス除去性能に関しては、膜分
離活性汚泥法は非常に良好な除去性能を示し、好気時間が長いほど活性汚泥中のノロウィルスは減少傾向がみられた。汚泥発生量は、SRT と良好な相関が見られ、SRT が長いほど、汚泥発生量は減少した。
膜分離活性汚泥法の大規模施設への適用方法として開発した膜分離ステップ流入多段硝化脱窒法について、その窒素・りん除去特性及び省面積効果について説明した。
【討議概要】「（5）ヨーロッパにおける膜分離活性汚泥法（MBR）の設計と操作」とあわせて質疑応答が行われた。
洗浄用空気量については、膜モジュールによってどのような特徴があるかという質問に対して、平膜の方が空気量は大きい傾向があるようだという回答がなされた。「コストは他の処理法に比較して大きいのではないか。特に膜交換費が大きいと思うがどうか。
」との質問に対しては、「技術開発によりコストは大きく削減されてきている。膜の寿命は 5～7 年としているのが一般的であるが、膜メーカーが 10
年保証をしている場合もある。」との回答がなされた。また、紹介されたセラミックスモジュールで、活性汚泥のろ過は可能なのかとの質問に対し、「小型プラントによる実験では、良好な成果が得られた。
これから、パイロットプラントによる実証実験を開始する予定である。
」との回答がなされた。さらに、「膜洗浄頻度と薬品量は。洗浄により活性汚泥に影響はないのか。」との質問には、「福崎では、薬品洗浄は年 1 回だけであった。活性汚泥への影響は特に見られていない。ドイツの施設におけるメインナン
スクリーニングの頻度については、発表のペーパー中の表にまとめてあるので参照されたい。」と回答された。
（7）ベルリンにおける下水の集中管理システム○ ベルリン市及びベルリン水道事業体の概要
ベルリン市の面積：889km2、人口：339 万人
ベルリン市外周辺地域にサービスを提供している人口：水道 94,000 人、下水道 51 万人
ベルリン水道事業体の職員：5,210 人、運転管理部門は 1,900 人
下水道関連

管渠延長：9,330km、うち 80％が分流式、20％が合流式
圧送管が 1,109km
雨水貯留池：22、ポンプ場：147、処理場：6、処理能力：平均 65.3 万ｍ3/日、最大 121.3 万ｍ3/日

ベルリン水道事業体は市（50.1％）と民間（49.9％、Veolia と RWE）の共同企業体。基本となる 3 つの方針は、経済性、環境への配慮、社会の安全確保である。会社のトップは市から派遣され、今のトッ
プは市の議員で経済が専門の人なので経済性を重視している。
○ 下水道施設の特徴
下水道施設の特徴として、5 か所の処理場はベルリン市域外の周辺部に立地していて、遮集下水の大部分はポンプ圧送によりそれらの処理場に送水されている。また、主要ポンプ場のうち、地理的に可能なポンプ場は、2 か所の処理場に送水できるようになっていて、局所集中的な雨天時の増水時に余裕のある処理場にも送水することで未処理下水の放流を減らしたり、工事・維持管理に伴う一時的な送水ルートの変更や処理場間の水量配分の変更に対応したりするなど、状況に応じて下水の送水を柔軟に運用できるようにしている。
○ これまでのポンプ場の運転自動化の取り組み
西部ベルリンでは、1960 年代にポンプ場更新計画が立てられた。その内容は、当時手動で運転されて- 10 -

いた 55 の施設を自動化し、主要ポンプ場で集中制御するものである。1999 年の Wilmersdorf ポンプ場の更新完成により、この計画は完了し、有人の 7 か所の主要ポンプ場で集中制御が始まった。
一方、東部ベルリンのポンプ場は構造面でも技術面でもかなりひどい状態であり、運転は主に手動で行われていた。西部ベルリンと異なり更新を終えた施設はわずかであった。
ポンプ場で働く職員の経費を削減するために、いくつかのポンプ場では既存の施設や設備のままでの遠隔制御等の自動化が進められたが、トラブルが増加するリスクを覚悟した上での実施であった。東部
ベルリンの主要ポンプ場の自動化は 2000 年の Mitte ポンプ場の更新で完了したが、7 か所は現在でも手動運転で、更新時に変更予定である。職員の年齢構成から今後退職者をいかに補充していくかという問題もあった。
○ 中央集中制御システムの構築
従来、146 のポンプ場は、13 の有人の主要ポンプ場で集中制御されていたが、主要ポンプ場の間でポンプ運転の情報を共有する仕組みはなく、有機的に連携した運転はされていなかった。
2001 年 10 月にポンプ場と処理場の運転管理の監視制御システムの構築を行う計画が決定された。目
的は、エネルギーの節約、人件費の節減、雨天時放流量の削減などである。ただし当面はポンプ場のみを集中制御化して、各処理場の処理能力に応じてポンプ場を遠隔制御するという基本方針で取り組んでいる。計画では、146 のポンプ場のうち、晴天時送水量が 6,000m3/日又は最大送水量 0.1ｍ3/秒以上の 44のポンプ場の能力増強と高度自動化（水位制御→水位･流量制御＋運転支援システム（シミュレーショ
ンシステム･予測システム）＋ポンプ運転情報システム）、13 の有人主要ポンプ場の完全自動化（無人化）
及び 1 か所の中央制御センターからの遠隔制御の実施などが盛り込まれている。2006 年 5 月からは 13の主要ポンプ場のうち 8 か所が中央制御センターとつながるようになった。将来的には中央制御センタ
ーにすべてのポンプ運転情報を集めて集中的に制御を行う予定である。
○ 雨水対策料金
舗装された土地の所有者から雨水対策の料金を 2000 年から徴収している。料金は舗装された土地 1m2
あたり年間 1.4EUR（210 円）である。芝生などの浸透地は対象外で、屋根の雨を貯留して利用している場合は半額免除となる。道路管理者も当然同じ率で負担している。雨水対策（浸水対策、CSO 対策、雨
天時増水分の処理など）について、初期投資は市が行ったが、維持管理と更新・追加の投資は会社の負担となるため、その費用に充当するためである。
因みに、ドイツの他の都市でも雨水関連の料金を徴収しているところが多いそうである。
【討議概要】「ベルリンには多くの湖があり、水浴その他のレクリエーションに利用されているが、湖への CSOの流入対策として、どのような対策を検討しているのか」という質問がなされ、吐き口を変更する計画
や CSO を土壌で処理する計画があるという回答がなされた。
（8）既存処理場を活用したステップ流入 2 段硝化脱窒法による高度処理施設への改築更新
京都市鳥羽水環境保全センターの既存二次処理施設反応槽の更新にあわせて、ステップ流入 2 段硝化
脱窒法による高度処理化を図った。その結果、処理能力あたりの建設費は標準法に比較して 64％程度高
くなり、また単位下水量あたりの消費電力量は 60％程度高いが、概ね理論値とおりの 70％の窒素除去率を得ることができた。維持管理コストを低減するため、例えば反応槽内に設置した撹拌機の間欠運転
や、インレットヴェーン付きのブロワを導入するなどの対策を取っている。京都市では今後とも計画的に高度処理の導入を進めるとともに、高度処理施設の経済的な運転管理のために調査・研究を重ねてゆく予定である。
【討議概要】
A2O 処理も行っているようであるが、なぜそのデータとの比較をしなかったのかという質問がなされ、- 11 -

鳥羽水環境保全センターには流入渠が 2 つあり、A2O を導入した系列とステップ法を導入した系列では水質の異なる別の流入渠の下水を処理しているため比較しなかったという回答がなされた。反応槽のMLSS が低いようであるがなぜかという質問に対しては、「低くしているわけではなく、流入下水の汚濁負荷が低いため、高くならないのである。以前に MLSS を高くしようとしたことがあるが，SRT が長くなりすぎて透視度が悪くなったことがある。」との回答がなされた。また、流入下水の水質濃度が低いのはなぜかとの質問があり、完全に分かっているわけではないが、不明水の浸入が原因と考えられると回答された。
2.3 セッション２「汚泥処理と再利用」（9）下水処理場における腐敗槽汚泥の処理○ プロジェクトの目的
Prack コンサルタントは環境分野のコンサルタントで、ドイツ国内のほか、ナミビア、ポーランド、
タイなどでも業務を行っている。
発表するプロジェクトは 1998～2001 年に行われたもので、腐敗槽などからの屎尿系汚泥を下水処理
場で下水と混合処理することによりコスト縮減を図るものである。背景は、下水道区域外で使用されている腐敗槽から出る汚泥の効率的な処理と、東ドイツで最近建設されたが需要が伸びず能力に余裕のある下水処理場の活用であり、腐敗槽汚泥を余裕のある下水処理場で処理する方式を確立することでコスト縮減を図ることが目的である。
○ ドイツにおける下水道の現状（1998 年時点のデータ）
旧の西ドイツ人口 6600 万人

下水道への接続率 93.5％

東ドイツ

1600 万人

70.0％

旧東ドイツでは 500 万人が下水道に接続できない状況であり、その 500 万人のうち 85％は腐敗槽を利用している。下水道への接続は少しずつながら増えているが、当分の間、腐敗槽の汚泥の処理は重要な課題である。
○ 腐敗槽及びその汚泥
対象汚泥は 3 種類、Septic tank からの汚泥、Cesspool からの汚泥、汚泥処理を持たない小規模下水処
理場の汚泥である。（注：タイトルの Septic tank と 3 つに分けたときに用いられている Septic tank とが同じものを指すのか、前者が広義で後者が狭義なのかは不明）
Cesspool（貯留型）は、貯留＋沈殿＋放流を行う。槽からは浸透できない構造。
Septic tank（浸透型）は、槽の下部から浸透できる構造。
対象汚水は屎尿と雑排水。腐敗槽の 85％は貯留型、その容量は 1 か月分の汚水量、80L/日･人、4 人/戸で、概ね 10ｍ3。
1998 年時点での腐敗槽汚泥の処理は、75％が下水処理場搬入、農業利用 11％、コンポスト 4％、埋立2％であった。
○ 下水処理場での腐敗槽汚泥の受け入れ基準
ドイツ下水道協会基準では、下水処理場での屎尿系汚泥混合処理の受け入れ基準は、設計処理能力が1 万人当量以上の処理場で、十分余裕があり、屎尿系汚泥投入量が当該処理場の処理能力 1 万人当量あたり 20ｍ3 以下かつ当該処理場の流入下水量の 5％以下であることとなっている。
屎尿系汚泥の性状

BOD 2,500mg/L（500～5,000）、COD 6,000mg/L（1,000～15,000）（ドイツ下水道協会参考値）

NH4-N 300mg/L（100～500）、T-P 150mg/L（50～400）

下水処理場への屎尿系汚泥の投入限界を調べるため、コンテナ型実験装置を用いて下水と汚泥を生物反応槽に投入する実験を 1999～2001 年に行った結果、下水量の 50％の屎尿系汚泥を投入しても処理水- 12 -

水質基準を満足できることがわかった。
人口密度の低い地域での排水処理について、腐敗槽＋汚泥の下水処理場での処理、小規模（地域）下水道への接続、大規模下水道への接続という 3 つの組み合わせを比較したところ、腐敗槽＋汚泥の下水処理場での処理という組み合わせが最も経済的であることが判明した。
【討議概要】「日本では下水処理場での屎尿受け入れは 5％が限度との実験結果がある。また処理水の色度の問題があった。そのような色度の問題は起こらなかったか。」との質問がなされ、「屎尿系汚泥の量が多いときは再処理が必要な場合もあったが、色度の問題はなかった。屎尿系汚泥の性状は非常にばらつくが、それらの性状を詳しく調査するようなことはあまりないので、性状を十分調査すれば屎尿系汚泥の投入量が増加できることが判明するであろう。」との回答がなされた。屎尿系汚泥を下水処理場の消化槽で受け入れることは検討していないのかという質問に対しては、消化槽への投入はやっておらず今後の研究テーマと思うとの回答があった。また、腐敗槽の建設に市から補助はでないのかという質問には、生活排水の適正な処理は市の責務となっているが、財政面の事情もあり市の補助を得るのは難しいようだと回答された。
（10）北九州市における汚泥の有効利用
本市は、浄化センターから発生する下水汚泥の最終処分をごみとの混焼とセメントの原料化による二つの方法によって有効利用を図っている。北九州市には、ごみ焼却工場が 3 か所存在するが、日明浄化センターに隣接する日明工場から発生する蒸気を利用して、北九州市の下水汚泥の半分を乾燥汚泥（含水率 40％）としている（乾燥施設稼動は、平成 11 年）。その乾燥汚泥は、日明工場と皇后崎工場でごみと混焼し、蒸気及び電力に生まれ変わる。蒸気は乾燥汚泥の熱源に、電力は、浄化センターの稼動電力となっている。こうすることでバイオマスのエネルギー循環を達成している。また、平成 9 年から、全国に先駆けてセメント原料化しており、いずれの方法も国内最大規模を誇っている。一方、本市は、平成 16 年に「世界の環境首都」実現のためのグランドデザインを発表し、その中で地域の環境負荷低減を掲げている。このため、地球温暖化対策としての二酸化炭素削減に向けて、汚泥の燃料化の実証試験等を実施するなど、新たな汚泥有効活用の検討を始めている。
【討議概要】
次世代の汚泥処理方式を検討しているとのことだが、その主目的は何かという質問がなされ、主目的は汚泥処理経費の削減であるという回答がなされた。また、「太陽光発電設備を導入して、汚泥処理の電力として使用するようなことは考えてないか。また、その投資効果の試算はしてないか。」という質問に対しては、浄化センターにおいて太陽光発電設備の導入は考えてないが、風力発電設備導入に向けて風況観測を行っているという回答がなされた。
（11）下水汚泥の油温減圧式乾燥技術に関する性能評価研究
福岡県では、下水道事業の進展に伴う下水汚泥発生量の増加に対し、それらの安定的な処理処分および地球環境の保全を目的とした下水汚泥の有効利用技術について検討し、「油温減圧式乾燥技術」に注目した。そこで、下水道新技術推進機構と共に本技術について共同研究を実施した。
共同研究の内容は、平成 8 年度に実用化研究をおこない、実設備の設計諸元を設定した。また、平成
14 年度に実設備を建設し、平成 15 年度に実設備を用いた性能評価研究として実証運転調査を実施した。
今回のワークショップでは、1）本技術の概要、2）本研究の最終ステップである性能評価研究の結果、
3）本技術の社会的な意義（可能性）について発表した。
本技術は、脱水汚泥を廃食用油と混合し、減圧加熱することで汚泥を短時間で乾燥・減容化することを目的として開発された技術であり、下水汚泥を負圧環境下で加熱し，含水率約 3.0％の乾燥汚泥を製- 13 -

造する。また、乾燥汚泥は廃食用油を含むことから発熱量が高く、セメント製造における助燃材や石炭などの代替燃料として有効利用が期待できることを報告した。性能評価の結果については、各乾燥性能値を満足し、経済性（イニシャル＋ランニングコスト）は埋め立て処分と同等以下、温室効果ガスの削減効果に有効であることを発表した。最後に、本技術で製造した乾燥汚泥の石炭火力発電所におけるサーマルリサイクルの実施例を紹介し、本技術の社会的な意義や今後の可能性について発表した。
【討議概要】
ドイツ側から、下水汚泥を減容化するだけではなく、減容化後の汚泥の利活用を配慮し、廃棄物である廃食用油を用いて下水汚泥の価値を高めていることについて賞賛のコメントがあった。また、廃食用
油の価格、必要品質について質問があった。
日本側から、価格については、実績値を示したうえで、維持管理費に影響のない範囲であるとの回答が行われた。また、品質については、外食産業から収集される廃食用油であれば受け入れ時には問題のないことが報告され、循環利用される油については酸化値を管理しているとの説明が行われた。
（12）下水処理場を核とした地域バイオマスの利用
下水道の資産である処理場を活用した地域バイオマス利用について検討を行った。地域バイオマスとして、公共事業由来の有機質廃材に着目し、モデル地区において正確なバイオマス発生量、種類などの調査に取り組んでいる。
次に、草木系の有機質廃材と下水汚泥の利活用を推進するため、両者の特性を活かした効果的な資源化技術の開発を行った。その結果、草木に蒸気加圧爆砕法を施したもの（以下、「爆砕木質」という。）と下水汚泥との混合嫌気性消化は実用可能と判断され、バイオガス生産に大きく寄与できることが示された。また、発酵残渣に関しては、緑農地利用に資するための液体コンポスト化法を開発した。
最後に、バイオガス供給可能量の推定を行い、天然ガス自動車の燃料として利用する技術を紹介した。
処理の効率化、全汚泥で消化を実施した場合、余剰消化ガス発生量はそれぞれ約 2.5 億 m3、約 3 億 m3と推定された。現在は、バイオガスを精製したものが「天然ガス」と同等であることを個別に検査する必要があるが、精製システムを基準化することで、バイオガス自動車の導入が容易になるものと考えられる。
【討議概要】「爆砕時の温度と圧力を教えてほしい。また、爆砕により、非分解性の成分を含む液体が生じると思うが、問題は発生しなかったか。」という質問がなされ、「実験的な取組みのため、正確な温度は把握していない。液体については（メタン化で消費されると思うが）水処理で対応が可能と考える。」という回答がなされた。
「液体コンポストは加温プロセスか。また、酸素はどのように添加したのか。」との質問に対しては、「2L の加圧容器を使用した実験。また、35℃で良好な反応であり、加温としては高いものではないと考えている。」と回答がなされた。爆砕木質を用いる場合、皮を混合するかどうかで大きな違いがあると思うがどうかとの質問がなされ、爆砕の原料としてチップ材を使用しており、検討を行っていないとの回答がなされた。また、爆砕木質を用いて得られるバイオガスにより、全体のエネルギ
ーバランスは取れるのかと質問され、計算例は示していないが、このシステムでエネルギー回収ができるものと考えていると回答された。最後に、爆砕は実スケールであれば、高価になるのではないかとのコメントに対しては、これから実スケールの建設を目指しているが、高価なものになるとは考えていな
いと回答され、オリジナルには木質をセルロースまで分解するものであり、そこがポイントであるとのコメントがなされた。
2.4 セッション 3「水処理と分散処理システム」（13）下水処理水の再利用- 14 -

発展途上国で衛生施設の普及させる一方で、環境に優しい方法で食料の増産を目指すために、今後下水の農業利用をますます推進させる必要がある。イスラエルやアルジェリアにおける下水処理水の灌漑利用などの実例のほか、今後期待される小規模集落排水処理及び有効利用方法のひとつとして、grey
water、brown water、yellow water の分離処理が紹介された。この分離処理システムにおいては、各排水はそれぞれに適した方法で処理される。grey water については、MBR（膜分離活性汚泥法）により処理
され、処理水は灌漑目的等に再利用される。brown water については、嫌気性処理プロセスにより、メタ
ンガスと肥料が回収される。yellow water については、沈殿－ストリッピング－吸着法により、含有される窒素とりんが肥料として回収される。
【討議概要】
ドイツにおける下水の再利用の状況はどのようなものかという質問がなされ、「現在は少ないが北部地域で灌漑に用いられている。その他、ゴルフコースへの散水や個別に再利用している箇所があるが、再利用水量やその割合については、把握されていない。」という回答がなされた。yellow water は直接に利用できるのに、なぜ処理するのかという質問に対しては、中に化学物質などが含まれているためであるという回答がなされた。また、分離処理を推奨しているが、収集するのは容易なのかとの質問がなされ、「大規模な集合処理ではなく、管渠が短いので容易である。また、真空で収集するため問題ない。」との回答があった。最後に、「yellow water と grey water を分離する建物がドイツにできるらしいが。」との質問には、フランクフルト政府機関の建物に導入を計画していると回答された。最後に、「分離処理システムの運営は誰が行なうのか。また、コストについては。」との質問があり、「運営は自治体が行なう。コストは水道料金の 1/2 程度と考える。エネルギーの 1/2 は嫌気性消化で賄える。」との回答があった。
（14）日本における再生水利用の現状と下水処理水の再利用水質基準等マニュアルの策定
下水処理水は、都市内における貴重な水資源として、今後もますますその再利用が重要になっていく
ことが予想され、それに伴い下水処理水の適切な再利用がより一層重要なものとなっている。このため、国土交通省は、下水処理水再利用に関わる水質基準等に関する委員会を設置した。委員会では、水洗用
水、散水用水、修景用水（人間が触れることを前提としていない環境用水）、親水用水（人間が触れることを前提としている環境用水）の 4 用途を対象に、①利用者の衛生学的安全性の確保、②再生水利用施設における美観・快適性確保、③下水処理水再利用システムの施設機能障害防止、の 3 つの観点を踏まえた再利用に関する新たな技術上の基準の策定を行うとともに、再利用にあたり必要となる考慮事項
をとりまとめた。国土交通省では、委員会においてとりまとめられた成果を「下水処理水の再利用水質基準等マニュアル」として公表した。本マニュアルでは、従来の再生水の指針・マニュアルで定められている大腸菌群に代え、大腸菌（100mL あたり不検出）が新たな基準として設定（修景用水を除く）されるとともに、施設基準が新たに規定され、施設が適切に機能していることを担保する指標として濁度が規定された。また、下水処理水再利用実施にあたっての考慮事項として、残留塩素管理対策、誤接合防止対策、誤飲防止対策等が定められる等、衛生学的安全性の強化が図られた。
【討議概要】
ドイツ側より、衛生学的安全性の検討状況について質問があり、ウイルス等検討途上にあるとの回答がなされた。
（15）急速に成長する都市域での半集中型の水システム
世界中の大都市の急激な発展はインフラ（社会基盤）整備につながる。それらのインフラにおいて、給水に関する問題と公衆衛生を維持するシステムの重要性に関して従来の集中型の水システムでは大都市の急速な成長と給水及び公衆衛生の維持に関する需給バランスがとれていない（発展にシステムが- 15 -

追いついていない）と、いくつかの途上国の例を挙げて説明があった。そのような課題を解決するシス
テムとして、大都市をある程度の区域に分割する半集中型の水システムの開発について発表があった。
半集中型の水システムの利点として、1）管渠及び下水道システムがコンパクト、2）再利用のために
水及び栄養塩類の循環が容易、3）産業排水と生活廃水の分離が容易、4）システムの拡大、最適化が容易、等が挙げられる。具体的な期待としては、給水の面では、灌漑用水や道路清掃やトイレ用水には雨水等を用いるなど、用途にあった質の水をフレキシブルに給水することにより、地盤沈下及び塩水遡上の原因と言われる地下水の使用を低く抑えることができるとのことであった。排水処理の点では、比較的処理の容易な grey water と不純物を含む black water のラインを分けて、grey water は簡易処理して再循環させる等、処理の効率化が図れる。廃棄物処理の点では、嫌気性消化残渣に対し、嫌気性消化＋乳酸
発酵の最適化を有効と考え、実証中とのことであった。
本システム開発の現状は、処理人口 5 万～10 万人規模が妥当と考えて研究を進めている。何よりも、都市の急速な発展にリンクしたインフラ整備の実現を目指して研究を進めていきたいとのことであった。
【討議概要】
3 月にメキシコシティで行われた第 4 回世界水フォーラムの分科会で、ドイツ側から屎尿分離システ
ムのビルの話を聞いたという日本側からの話題提供に対して、それはフランクフルトの政府庁舎で計画されているプロジェクトであると回答された。スイスでも同様のビルが建設され、医薬品等の微量化学
物質の挙動が調査された。化学物質は尿側に分離されるはずであったが、実際には屎側にも相当量存在することが確認された。
発展途上国における急速な都市人口の増加に伴って発生するスラム地域の衛生問題に対して、半集中型の水システムは対応できるかとの日本側からの質問に対して、このシステムは、先進開発国を念頭においたもので発展途上国には高価すぎるとの答えであった。ただし、低開発国における低所得の人口密集地域では、地区毎に「水の家」を設置し、シャワーやトイレや洗濯に供するという考え方がある。高所得地域でも、海水淡水化によって水供給が行われているような乾燥地帯では、grey water の再利用が有効な方法である。
（16）バイオガス、アンモニア、りんのリサイクルを伴う半分散処理による都市排水管理
ドイツにおける従来の下水道システムは合流であり、雨水と生活排水が埋設された下水管を用いて終末下水処理場に集約され、生物処理等が行われている。ただし、放流水にはマイクロ汚染物質の流出が検出される例もある。また、年間の総降水量に変化はないが、地球温暖化に伴う気候変化による局所的な集中豪雨が観測されており、雨水氾濫の危険性を含んでいるとの報告があり、それらの課題を解決することを目的としたプロジェクト「DEUS21」について発表があった。本プロジェクトは、都市開発地域における準分散型の水と排水のマネージメントを主眼におき、下水管を用いた自然流下による下水の収集に代わり、真空管を用いた収集システムを用いている。また、比較的水質のよい雨水を生活排水と分けて貯留し、灌漑用水等に再利用することによって負荷変動の平滑化をはかり、雨水氾濫の未然防止と収集システムの最適化を目指している。
本システムは、処理人口 100～10,000 人程度の規模をターゲットとしている。
ドイツ連邦教育研究省の支援を受けてフォルツハイム近郊の Knittlingen という小さな町で稼動している真空下水処理システムの施設及び運転状況について発表された。
【討議概要】
下水処理水の再利用状況についての日本側からの質問に対して、ドイツでは以前から処理水の灌漑利用が行われてきたことが紹介された。かつては機械的な処理のみが行われた下水が使われていたが、現在では活性汚泥処理された下水が利用されている。冬場は硝化・脱窒処理が行われるが、夏場は行われ- 16 -

ない。ゴルフ場で利用されている例もある。
小規模なリサイクルシステムの維持管理責任者に関する質問に対して、地方自治体の水道、地下水、流出雨水の水質担当責任者が兼ねている旨の回答があった。
日本側からリサイクルシステムの経済性について質問したところ、経済性についての評価はまだ十分に行われていないとの回答であった。ただし、アンモニアの抽出はハーバー・ボッシュ法よりエネルギーコストが小さく、嫌気性処理プロセスからエネルギー回収が期待できる。
準集合処理では、施設の維持管理人員が増えるのではないかという日本側からの疑問に対しては、技術的支援の人員は必要であるが、維持管理人員は必要ないこと、発展途上国においても大学の協力や ITを活用することによって、維持管理人員の増加は避けられるとの回答があった。日本側からは、コミュ
ニティの協力が重要であるとのコメントが行われた。
発展途上国に対する援助の国別優先付けについての日本側からの質問に対して、ドイツ側から、これは教育研究省とは別の官庁（経済協力省）の所管であり、経済協力省は、新技術については理解がない
が、技術協力で大きな役割を果たしている民間企業のなかには新しい方式に関心を持つものもあるとの回答があった。ブルガリアやルーマニアなどヨーロッパのなかにもインフラが十分に整備されていな国
では、新しい技術に対する需要があると考えられる。
ドイツ側から、発展途上国については、窒素やりんの再利用のほかにエネルギーと維持管理の経済性が重要な課題であるとの指摘があった。
2.5 セッション 4「水管理（雨水、浸透、管渠システム）」（17）雨水貯留施設と管渠の清掃装置（ハイドロセルフ）
ドイツ国内を始めとして、ヨーロッパ、世界で 1,000 施設以上の HydroSelf が設置されている。その
成功は、ダム開放に似たフラッシュ波を起こすフラッシュゲートに拠る。フラッシュゲートを素早く流出した波は、貯留池や下水管を 1 回のフラッシュで洗浄する。
特徴として、次の事項があげられる。洗浄力は 100m 以上、洗浄水は貯水槽に自動的に蓄えられ、管理が簡単。また、計画段階からの支援で安全に建設できる。タンクは矩形でも円形でも、大きくても小
さくてもよい。
既に設計計画ができていても、多くの場合に設置が可能である。最も大切なことは、洗浄水が蓄えられることである。そのタンクの大きさと、最終的にフラッシュゲートの幅を決定する。大きな施設では、排水先の洗浄が一旦終わってから、次の洗浄が開始される。
【討議概要】
乾燥時の臭気が問題になると思うが、洗浄水の水質は雨水と同じ程度かという質問がなされ、「下水管内は通常下水が流れているので、問題にならない。また、排水区域から流出がなくなった時点で洗浄は終わる。最大でも 2 日だが、その時点では貯水槽の臭気も問題にならない。」という回答がなされた。
既存の貯留池に設置はできるかとの質問に対しては、80cm から 1m のスペースがあれば設置が可能との回答がなされた。また、貯留池の場合のガイドウォールの高さ、下水管の最小管径につき質問があり、「ガイドウォールの高さは 40～60cm 程度であり、堆積物の高さを考慮する。このフラッシュゲートは貯留池用だが、下水管用は現地調査のときに紹介する」と回答がなされた。オープニングゲートのメカ
ニズムの詳細につき質問がなされ、「フロートの上昇がハイドロリックシリンダに伝達されフックが外れる。一つの列の洗浄が終わると、次の列のゲートが開き、順番に洗浄を行う。」と回答がなされた。
最後に、洗浄水として下水も利用できるかとの質問がなされ、「小規模なものとして 400mm までの下水管に適用した事例がある。洗浄距離は 600～700m だが、1km まで伸ばすことを検討している。
」との回答がなされた。
- 17 -

（18）下水道未普及地域の解消に向けたプロジェクト○ 背景
日本には下水道で整備が計画されていながら整備の遅れで下水道を使えない人が 2400 万人存在する。
国及び地方自治体の厳しい財政事情と、既に整備済みの施設の老朽化に伴う更新需要の増加などを踏まえて、下水道未普及の解消に向けて、従来の手法に頼るのではなく、計画から施工までのあらゆる面でコストの縮減及び工期の短縮をもたらす斬新なアイデアを実践するというプロジェクトを国が中心となって本年 9 月より実施している。
○ 未普及人口の分布
2004 年度末時点で下水道が整備されている人口は全体の 68%、浄化槽が整備ずみもしくは整備予定という人口が 13%であり、残りの 19%が下水道で整備が計画されている下水道未普及人口である。都市の
人口規模別に未普及人口を求めると 1 万人から 100 万人まで広く分布していることが分かる。
○ これまでのコスト縮減の取り組み
1997 年から国をあげてコスト縮減の取り組みを進めており、下水道の分野でも管渠の道路埋設基準の見直しなどの成果が得られている。
具体的に K 市の管渠埋設工事（開削工法）でここ 10 年間のコストの変化を試算したところ、2006 年度の単価・基準等に基づく工事では 1996 年度と比べて 40%コストが下がっていた。主な理由は管周りの埋戻しに用いる材料を砂から改良土に変更したことと道路路盤の復旧幅を狭くして掘削幅と同じにしたことなどである。さらに埋設深さを浅くすること及び小型マンホールを用いることなどの提案を実施できればコストはさらに 20%引き下げることができる。
○ 下水道全体の整備コスト
一定期間の投資額と新規普及人口から求めた 1 人あたりの整備コストは 1998 年度から 2002 年度の平均として 1 人あたり 98 万円という値が得られている。1990 年以降に着手して整備をほぼ完了している
自治体の実績を基に整備コストを求めると、1 人あたりの整備コスト（Y：万円/人）は 1 人あたりの管渠延長（X：m/人）と明確な相関があり、Y=10X+50 という関係が得られる。
1m3 あたり 200 円という使用料により資本費が半分回収できるという条件で整備コストを試算したところ、投資額に占める起債の割合が 60％で、その利率が 3％の場合、1 人あたり 64 万円という値が得られた。
○ コスト縮減に向けたアイデア候補
国では本プロジェクトに関連して全国の公共団体及び関連団体に対してコスト縮減につながるアイ
デアの募集を行っている。これまでのアンケートで土木研究所でコスト縮減のための技術の候補として取り上げているものの中から、ベント管による伏せ越し、曲管、急勾配管渠について我が国での採用事例について紹介した。
（19）SPREE2011～科学、芸術、経済と都市計画の成功に向けた連携～
Spree 川流域には泥炭採掘跡が多く残り、溜まった水の流出が汚染源の一つになっている。ベルリン
市内では多くの水辺があるが、高架水路を作り泳いで通勤できたり、川に飛び込みができたりすれば素晴らしいだろう。
また、合流管からの流出も汚染源となる。貯留池を建設して、内側を彩色すればきれいだが、コンクリートが高価になる。そのまま下水を放流すると問題なので、川にバケツを作ればよい。具体的には、
雨水吐きの先にタンクを作ればよい。
タンクをたくさんつなげると、上部利用ができる。映画上映をしたり、飛び込み台にしたり、日焼け
サロンにしたり、テント村にしたり、様々に利用できる。その収益で、随分と経済的に建設できる。川- 18 -

沿いにたくさん建設すれば、いろいろな利用が可能となる。
【討議概要】
タンクの貯留量はどのくらいになるのかという質問に対しては、延長 2km の区間から 8,000m3 程度の雨水が流出するという試算があるという回答がなされた。具体的な検討状況につき質問がなされ、「パイロットプラントについて 5 人のエンジニアリング会社とフーバー社が経済面や技術面の検討を実施している。また、ハンブルグにおいて、合流区域の貯留池検討にも加わっているが、そこでは臭気は問題になっていない。」との回答がなされた。また、「タンクの材料は何か。コンクリートは高価だと思うが。」というコメントに対し、鉄骨とプラスチックを使ったコンテナを考えていると回答された。タンクは浮かんでいるのか、沈んでいるのかとの質問に対し、両方の可能性を検討しているとの回答があった。最後に、CSO が Spree 川の汚染源になっていると考えられるが、上流からの負荷も含めた流域管理は検討されているのかとの質問に対して、「汚染制御では E.coli の流出が課題になると思う。ビジョンを示すべきだと考えており、技術面での検討を進めたい。」との回答があった。
（20）都市域からの雨天時流出汚濁負荷量の実態及び推定方法
我が国における市街地ノンポイント対策の制度及び現状につき概観され、対策推進のための計画の枠組み、技術資料及び財政プログラムは存在するが、対策は積極的には実施されていないことが指摘された。よりよい計画や関連調査のために、さらなる知見及び技術的進展が求められるべきである。
生物化学的酸素要求量等の伝統的な水質項目、重金属及び環境ホルモンを対象として、市街地からの流出汚濁負荷量につき現地調査が行われ、流出水の濃度は流出水量に対応して時系列的に大きな違いを示し、排水区毎にもその特性が表れることが分かった。また、一降雨あたり平均水質（EMC: Event Mean
Concentration）は、どの水質項目についても環境基準又は予測無影響濃度（PNEC: Predicted No EffectConcentration）を上回り、受水域に無視できない影響がありうることが分かった。
市街地からの流出汚濁負荷量の予測手法について現地調査データを用いて調査がなされ、降雨毎の降雨関連情報を組み込んだ重回帰分析の手法が、多くはないデータ数で信頼性の高い推定結果を産み出す可能性があることが分かり、現在さらなる調査が継続中である。
【討議概要】
汚濁負荷量を推定するときに道路等の工種毎に分けないのかという質問がなされ、これに対して、確
かに工種毎に汚濁負荷ポテンシャルは異なりそれを踏まえた推定手法もあるが、本推定手法は排水区の土地利用を包括的に捉え比較的少ないデータで推定できるというメリットがあるという回答がなされた。
2.6 セッション 5「水環境と汚濁制御」（21）大阪市における総合的合流式下水道改善システム技術とその実施
大阪市では、市域の 97％が合流式下水道で整備されているため、合流式下水道改善手法、特に雨天時下水処理技術について、独自の調査や実験を行ってきた。そのなかで、雨天時活性汚泥法と凝集剤添加
傾斜板沈殿法は、既存の処理施設を活用し、雨天時下水連続処理能力を効果的に増加させることのできる、低コストで、かつ、早期に導入可能な技術として、実用レベルの開発に成功した。
雨天時活性汚泥法は、雨天時に設計最大時間汚水量の 2 倍量を反応槽の後段区画に流入させることにより、従来の 3 倍の雨天時下水を活性汚泥処理するもので、実験結果から長時間の降雨時や高い流入負荷の条件でも安定して運転できることが確認されている。
凝集剤添加傾斜板沈殿法は、傾斜板ピッチ 100mm、傾斜板流速 0.5ｍ/分以下、表面負荷率を 25m3/m2･日として、既存最初沈殿池を傾斜板沈殿池に改造することにより、従来の設計最大日流量の約 5 倍の雨- 19 -

天時下水の処理とするものである。
そして、大阪市では、合流式下水道からの放流負荷量を分流式下水道と同等以下に削減することを目標として、合流式下水道改善計画の改訂を行ったが、これらの技術を適用することにより従来の計画と比較して大幅なコスト縮減が見込まれるとの結果が得られた。
【討議概要】「ドイツでは雨天時下水の遮集量は晴天時下水の 2 倍で設計されているが、現在遮集量を増やすことが検討されており、この発表は参考になったが、雨天時活性汚泥法を導入するうえで何か問題は発生していないのか。」という質問がなされ、「現在、大阪市では各処理場に雨天時活性汚泥法を導入しているが、反応槽流出水を最終沈殿池に均等に分配するうえで工夫を要することがある。」という回答がなされた。日本では雨天時と晴天時で放流水質基準は異なるのかとの質問に対しては、「日本では雨天時は晴天時の放流水質基準は要求されない。しかし、雨天時活性汚泥法の処理水質は晴天時の通常の活性汚泥法での処理水質と比べてもほとんど遜色はない。」との回答があった。また、薬品を使うことで処理費用がかかるのではないかと質問がなされ、「傾斜板沈殿法では PAC を添加するが、傾斜板沈殿法を用いるのは流入下水量が晴天時下水の 3 倍以上の場合であり、年間の運転時間はそれほど長くない。また、傾斜板装置自体にはほとんど運転や保全の費用がかからない。」と回答された。
（22）下水処理工程におけるエストロゲンの挙動と下水処理水の生物影響
流入水、処理水及び河川水のエストロゲン様活性の濃度レベル、下水処理場におけるエストロゲンの挙動、エアレーションタンク DO 濃度とエストロゲン除去の関係、下水処理水の魚類に及ぼす影響について発表があった。
下水処理場ではその処理工程でエストロゲン様活性が約 80％減少しているが，下水処理水として
16ng/L-E2 活性等量（中央値）の濃度で環境水中に放出されていること、また、この濃度は河川濃度（中央値）より 2 桁高い値であり、今後、河川に占める下水処理水の割合が高くなる場合には、エストロゲ
ン様活性が上昇する可能性があるとの報告があった。
処理人口 30,500 人、処理能力 20,400m3/日の標準活性汚泥法を採用している下水処理場においてエス
トロゲンの挙動調査を冬期と夏期に行ったところ、E2 は両調査において高い除去率が確認された（冬期：70％、夏期：87％）のに対し、E1 については処理工程が進むにつれ濃度が増加（冬期：740％増加、
夏期：50％増加）し、その傾向は特に冬期に顕著であった。夏期は、硝化が進行する SRT、DO 濃度で運転が行われていたが、冬期には、硝化抑制のため、曝気量を制限する運転が行われており、このような運転条件がエストロゲンの処理に影響したのではないかとの説明があった。
MLDO を制御した回分試験を行い、MLDO が低い段階では E1 の変化が見られないが MLDO が 3mg/L程度に達した時点で急激に減少することを確認し、E1 の減少速度は溶存酸素濃度に大きく依存するとの報告があった。
エストロゲンが雄メダカのビテロジェニン生成に与える影響を調査し、暴露期間 14 日間での E2 の最大無作用濃度（＜5.0ng/L）、最小作用濃度（5.0ng/L）、E1 の最大無作用濃度（31.6ng/L）、最小作用濃度（79.5ng/L）を求めた。また、下水処理水に雄メダカを曝露したところ、エストロゲン様活性が 20ng/mL-E2を超えた二次処理水試験区のメダカでビテロジェニンの生成が確認された。これら下水処理水にメダカを曝露した試験から、試料水のエストロゲン様活性とビテロジェニン濃度との関係を求め、エスロトゲ
ン様活性が高いほどビテロジェニン濃度が上昇する傾向を確認したとの報告があった。
（23）水環境における医薬品類の分解特性
環境中における医薬品の検出、下水処理場における医薬品の除去について発表があった。
環境中における医薬品の検出については、病院排水、下水処理水、河川水、地下水、飲料水などから- 20 -

ng/L～μg/L 濃度での検出例があることが示された。
下水処理場における医薬品の除去については、抗生物質、鎮痛剤、殺菌剤、ホルモンなど薬効成分の違いにより下水処理場での除去率が大きく異なることが示された後、医薬品の除去について詳しい説明があった。
医薬品は、それぞれの効能別に対生物作用、安定性、分子構造等が異なった形でデザインされていることについて説明された後、pH の違いによって構造が変化してしまう例として Ciprofloxacin と
Ceftazidime Species の pH の違いによる形態変化について示された。また、構造式が異なる Clarithromycinと Roxithromycin の下水処理場での除去率について触れ、同じ抗生物質であっても構造式の違いにより安定性（除去率）が異なる（Clarithromycin：50％、Roxithromycin：25％）との報告があった。
下水処理場における医薬品の除去は、分解によるものだけではなく形態変化しているケースもあることについて幾つかの例を挙げて説明された。抗生物質の Piperacilin の例では溶解性有機化合物（DOC）の減少に加え、DOC が減少していくとともに構造が異なる有機化合物の存在を HPLC により確認したとの報告があった。
【討議概要】「（22）下水処理工程におけるエストロゲンの挙動と下水処理水の生物影響」とあわせて質疑応答が行われた。
微量化学物質除去についても良好な結果を示すことが多い MBR 処理水で医薬品濃度増加するケースがみられた理由について質問があった。これらの詳細理由については今後の研究に委ねる必要があるが、汚泥への吸着・脱着が関与している可能性があるとの説明があった。また、医薬品の除去性については生分解性が関係すること、MBR では SRT が長いことから良い除去率を示した報告があるとのコメントがあった。
現在生活で使用されている医薬品は数多くあるなかで、優先して調査すべき医薬品の選定方法について質問があった。調査対象医薬品は、研究目的によってそれぞれ異なることから、研究目的を明確に設定することが重要であるとの説明があった。
硝化が進行している低い pH 領域においてある種の医薬品除去率が高かったとの報告があるが、流入
水の pH と下水処理での医薬品除去率との関係について質問があった。医薬品のなかには pH により形態が変化するものもあることから、除去率は医薬品のタイプによりそれぞれ異なるものと考えるとの説明があった。
2.7 閉会
出席者全員の参加のもと、フアマンプロジェクト次長の司会により閉会式が行われ、次回の開催予定
や今後の共同研究に関するコミュニケの確認が行われ、今後も本ワークショップは継続することが確認され、次回は 2009 年に日本で開催されることになった。
また、水循環中の微量汚染物質、エネルギー及び物質の回収を含む経済的・環境的に最適な下水道シ
ステム、膜分離活性汚泥法を含む水の再利用、流域管理に関する共同研究プロジェクトの実施について検討することとした。

- 21 -

３．現地調査の概要(1) 下水の分離型処理技術
Berlin-Stahnsdorf 処理場にて、欧州連合実証研究「雑排水、屎、尿の分離型処理のための衛生概念」の現地視察を行った。研究では、真空式又は重力式のトイレで屎と尿とが分離して収集され、それぞれ
ら嫌気性消化処理等により肥料、コンポストが製造される。また、雑排水はウェットランドで処理され、膜による処理も実験中である。
(2) 管渠等清掃技術
管渠等を対象としたフラッシング技術につき、詳細な情報提供を受けた後、同技術が導入されている
雨水滞水池を有する処理場（Prichsenstadt 処理場）を視察した。同処理場は合流式の処理場であり、処理しきれない雨水の貯留という役割を雨水滞水池は担い、年に 10 回程度利用されている。視察では、ゲートにより貯められた水が一気に開放され、大きな掃流力を有することが確認できた。
(3) 膜分離等技術
フーバー社（ベルヒング）において、雨水処理、フラッシングシステム、下水の分離型処理、下水の再利用、膜処理技術につき情報提供を受けた後、同社内にある再利用公園及び膜処理実験装置を視察した。また、フーバー社が実験プラントを設置している Berching 処理場の視察も行った。

- 23 -

別添資料別添 1 ワークショップ記者発表資料
資料配付の場所
国土交通省記者会
筑波研究学園都市記者会
平成 18 年 10 月 6 日 同時配布

平 成 18 年 10 月 6 日
記
国

者
土

発
交

通

表
省

都市・地域整備局下水道部
国土技術政策総合研究所

日本とドイツとの下水道技術に関する国際会議が開催される―「第１０回日独排水及びスラッジ処理についてのワークショップ」の開催―
国土交通省では、海外との下水道技術の交流を深めるため、各種の国際会議、技術者相互派遣、共同研究、海外調査、技術援助等について積極的に取り組んでいる。特に、国際会議としては、今回１０月９日から、ドイツのベルリンにおいて、「第１０回日独排水及びスラッジ処理についてのワークショッ
プ」（以下、日独ワークショップという。）を開催し、情報交換及び活発な議論を行う予定である。
１．経緯
昭和４９年１０月に締結された「日独科学技術協力協定」に基づき、昭和５１年６月に「日独環境保
護技術パネル」が設置された。このパネルの第４回会合の席上でドイツ側より、下水道技術について専門家による情報交換を深めるためのワークショップの開催が提案された。
この提案を受けて準備が進められ、昭和５７年１０月に建設省土木研究所（当時）で日独ワークショ
ップの第１回会議が開催された。以降、概ね２年毎にドイツと日本で交互に開催されている。第１０回
会議はドイツのベルリンでの開催となった。
２．第１０回日独ワークショップの概要
第１０回日独ワークショップは、会議がベルリンで１０月９日（月）と１０月１０日（火）の両日にわたって開催される。会議は、５セッションについて、日本側は１２論文、ドイツ側は１２論文を英語で発表、討議を行う。会議の後、１０月１１日（水）から１０月１３日（金）にかけて、下水の分離型処理技術、管渠清掃技術、膜分離技術の現地調査を行う予定である。
（１）委員構成
日本側委員団は、国土交通省都市・地域整備局下水道部の那須下水道技術開発官を団長として、国土技術政策総合研究所、土木研究所、日本下水道事業団、下水道新技術推進機構、京都市上下水道局、大阪市都市環境局、北九州市建設局からの委員で構成される。
ドイツ側委員団は、カールスルーエ研究所のフアマン プロジェクト次長を団長として、アーヘン工科大学、ダームシュタット工科大学、ハノーバー大学、フライブルグ大学、ドレスデン工科大学、ベルリン水道事業体、ヴッパー水組合等からの委員で構成されている。（参考１参照）（２）会議プログラム
本会議では、「下水処理技術」、「水環境と汚濁制御」、「汚泥処理新技術」、「流域管理」、「分散処理と水利用」の５セッションにおいて、対策が必要となっている課題や最新技術についての発表を行い、日独双方にとって有益な情報交換および技術交流の場とすることを目的としている。（参考２参照）
問合わせ先： 国土交通省 都市・地域整備局下水道部下水道企画課
下水道技術開発官 那須 基
03-5253-8111（内線34162）、03-5253-8427（夜間直通）
国土技術政策総合研究所下水道研究部
下水処理研究室長 南山 瑞彦
029-864-2329- 25 -

参考１「第１０回日独排水及びスラッジ処理についてのワークショップ」委員構成（日本側委員）
那須 基
田中 修司
南山 瑞彦
吉田 敏章
酒井 憲司
尾崎 正明
小森 行也
村上 孝雄
藤木 修
怒木 茂
林 潔彦
藤田 眞
近藤 保光

団長、国土交通省都市･地域整備局下水道部下水道企画課、下水道技術開発官
国土技術政策総合研究所、下水道研究部長
国土技術政策総合研究所下水道研究部下水処理研究室、室長
国土技術政策総合研究所下水道研究部下水道研究室、主任研究官
土木研究所材料地盤研究技術推進本部、総括研究監
土木研究所材料地盤研究グループリサイクルチーム、上席研究員
土木研究所水循環研究グループ水質チーム、総括主任研究員
日本下水道事業団技術開発部、先端研究役・総括主任研究員
下水道新技術推進機構、研究審議役・研究第一部長
下水道新技術推進機構研究第一部、研究員
京都市上下水道局下水道部、鳥羽水環境保全センター所長
大阪市都市環境局総務部、事業評価担当課長
北九州市建設局施設部施設課、計画係長（ドイツ側委員）
R.ロスキルD.フアマン
R.フラー
J.ピネカンプ
M.ワーグナーK.ローゼンヴィンケル
K.キューメラー
P.W.グレーバー
A.ペーターフローリッヒ
G.ペーターB.ビーブッシュ
W.トロッシュ
S.パリス
J.スタインハート
H.シュミットホリックス
C.ハーレーR.スティーグ

ドイツ連邦教育研究省、研究部長(環境分野)
団長、カールスルーエ研究所、プロジェクト次長
カールスルーエ研究所、プロジェクトマネージャー
アーヘン工科大学、教授
ダームシュタット工科大学、教授
ハノーバー大学、教授
フライブルグ大学、教授
ドレスデン工科大学、教授
ベルリン水道事業体
ベルリン水道事業体
ヴッパー水組合
フラウンホーファー研究所、教授
プラントメーカー
プラントメーカー
プラントメーカー
技術コンサルタント
技術コンサルタント- 26 -

参考２
第 10 回日独排水及びスラッジ処理についてのワークショップ

プログラム(案)第 1 日目
日付
10/9(月)

セッション / トピック

時間
9:00 – 開会
10:00

発表者

所属

フアマン プロジェクト FZK
次長
那須 下水道技術開発官 本省
フラー プロジェクトマ FZK
ネージャー

10:00 – セッション 1: 下水道システムと下水処理
12:00-ドイツにおける最新の下水処理-下水道ビジョン2100-下水処理場における技術制御とエネルギー管理の現状-流域における効率的な汚濁負荷削減のための経済

ローゼンヴィンケル教授 TUH
田中 下水道研究部長
国総研
WVB
ビーブッシュ 氏
藤木

研究審議役

機構

ピネンカンプ 教授
村上 先端研究役
ペーター 氏林 鳥羽水環境センター
所長

TUA

ハーレー 氏近藤 計画係長
怒木 研究員PC尾崎

土研的実施策～排水賦課金と水質取引の比較～
12:00 – 昼食
13:00
13:00 – -ヨーロッパにおけるMBRの設計と操作
15:00-日本における下水処理へのMBR導入-ベルリンにおける下水の集中管理-既存処理場を活用したステップ流入2段硝化脱窒法による高度処理施設への改築更新

事業団
BWW
京都市

15:00 – 休憩
15:30
15:30 – セッション 2: 汚泥処理と再利用
17:30-下水処理場における腐敗槽汚泥の処理-北九州市における汚泥の有効利用-下水汚泥の油温減圧式乾燥技術に関する性能評価
研究-下水処理場を核とした地域バイオマスの利用

上席研究員

北九州市
機構

第2日目
日付

時間

セッション / トピック

10/10

9:00 –
11:00

セッション 3: 水利用と分散処理システム-下水処理水の再利用-日本における再生水利用の現状と下水処理水の再

(火)

発表者

HAG
パリス 氏
南山 下水処理研究室長 国総研

利用水質基準等マニュアルの策定-急速に成長する都市域での半集中処理システム
ワーグナー-バイオガス、アンモニア、リンのリサイクルを伴う トロッシュ
半分散処理による都市排水管理
11:00 – 休憩
11:30

- 27 -

所属

教授
教授

TUDA
FI

11:30 – セッション 4: 流域管理
13:00
-下水管集水域のための管渠清掃システム
スタインハート 氏-下水道未普及地域の解消に向けたプロジェクト
酒井 総括研究監-SPREE2011～科学、芸術、経済と都市計画の共同に スティーグ 氏

SG
土研
LURI

よる成功事例～
13:00 – 昼食
14:00
14:00 – -都市域からの雨天時流出汚濁負荷量の実態及び推
15:30
定方法

吉田

主任研究官

国総研
TUDR

-下水処理水の漏水

グレーバー

セッション 5: 水環境と汚濁制御-大阪市における総合的合流式下水道改善システム

藤田

担当課長

大阪市

小森

総括主任研究員

土研

教授

技術とその実施
15:30 – 休憩
16:00
16:00 – -下水処理工程におけるエストロゲンの挙動と下水
17:00
処理水の生物影響-水環境における医薬品類の分解特性
17:00 – 閉会
17:30
本省:
国土交通省
国総研:
国土交通省国土技術政策総合研究所
土研:
土木研究所
事業団:
日本下水道事業団
機構:
下水道新技術推進機構
京都市:
京都市下水道局
大阪市:
大阪市都市環境局
北九州市: 北九州市建設局
BMBF:
FZK:
TUA:
TUDA:
TUDR:
TUF:
TUH:
BWW:
WVB:
FI:
HAG:
SG:
PC:
LURI:

Federal Ministry of Education and Research
Research Center Karlsruhe
Aachen University of Technology
Darmstadt University of Technology
Dresden University of Technology
Freiburg University of Technology
Hannover University of Technology
Berlin Waterworks
Wupperverband
Fraunhofer Institute
Huber AG
Steinhardt GmbH
Prack Consult Ltd.
LURI Waterssystems Ltd.

- 28 -

キューメラー

教授

TUF

別添 2 ワークショップ日程（英文）Program of the 10th Japanese-German Workshop on Waste Water and Sludge Treatment
9 Oct, 2006
Time

Session / Topic

Presenter

Affiliation

Opening session
9:00 -Head of the German delegation
9:20 -Head of the Japanese delegation
9:40 -Introduction to the workshop

D. Fuhrmann
M. Nasu
R. Furrer

FZK
MLIT
FZK

Session 1: Sewerage systems and waste water treatment
10:00 - Municipal wastewater treatment in Germany - state of the art
10:30 - A century-long strategy for wastewater -system management in Japan;
concept shifts from the wastewater systems to the roads toward recycling
society
11:00 - Development of a technical controlling and energy management system
within the Wupperverband - an interim report
11:30 - Economic instruments for basin-wide efficient pollution load reduction-comparison between effluent charge and water quality trading-

K. Rosenwinkel TUH
S. Tanaka
NILIM

B. Wiebusch

WVB

O. Fujiki

JIWET

12:00- Lunch
13:00
13:00
13:30
14:00
14:30

- Design and operation of membrane bio-reactors in Europe
J. Pinnekamp- Japanese experience of MBR application to municipal wastewater treatment T. Murakami- Central management of Berlin waste waters
C. Sieker- Renovation of secondary treatment facility into the step-feed biological
K. Hayashi
nitrogen removal process by the effective by the effective use of the existing
structure

TUA
JS
BWW
Kyoto

15:00- Coffee break
15:30
Session 2: Sewage sludge treatment and reuse
15:30 - Treatment of sludge from septic tanks in municipal waste water treatment
C. Harley
plants
16:00 - Utilization of sewage sludge in Kitakyushu City of JapanY. Kondo
16:30 - Performance evaluation research on type of the sewer sludge drying using a S. Ikarugi
oil bath under diminished pressure
17:00 - Utilization of regional biomass centered on wastewater treatment plants
M. OzakiPC
Kitakyushu
JIWET
PWRI

10 Oct, 2006
Time

Session / Topic

Presenter

Affiliation

Session 3: Water reuse-decentralized systems
9:00
9:30
10:00
10:30

- Reuse of treated waste water- Establishment guidelines for the reuse of treated wastewater- Semi-decentralized water systems for rapidly growing urban areas- Semi-decentralized infrastructure in the development area of Knittlingen,Germany- 29 -

S. Paris
M. Minamiyama
M. Wagner
W. Trösch

HAG
NILIM
TUDA
FI

11:00- Coffee break
11:30
Session 4: Water management (storm water, infiltration, sewer
11:30 - Hydroself flushing systems for storage basins and sewers
12:00 - Report on the "extension of sewerage systems to everyone who needs it"
project
12:30 - SPREE 2011 -Successful cooperation of engineering sciences, arts,
economics, and city planning

J. Steinhardt
K. SakaiSG
PWRI

R. Steeg

LURI

14:00 - Present status and estimation method of pollutant load in wet weather flowfrom urban areas
14:30 - Seepage modelling of cleared waste water
Session 5: Aquatic environment and pollution control

T. Yoshida

NILIM

P.W. Gräber

TUDR

15:00 - Development of wet weather sewage treatment technologies and theirapplication to a combined sewer system improvement plan in Osaka city

M. Fujita

Osaka

K.Komori

PWRI

K. Kümmerer

TUF

13:00- Lunch
14:00

15:30- Coffee break
16:00
16:00 - Fate of estrogens in sewage treatment process and effect of treated sewage
on fish16:30 - Degradability of pharmaceuticals in the aquatic environment
17:00- Closing session
17:30
MLIT:
NILIM:PWRI:JS:JIWET:
Kyoto:
Osaka:
Kitakyushu:

Ministry of Land, Infrastructure and Transport, Government of Japan
National Institute for Land and Infrastructure Management, MLIT
Public Works Research InstituteJapan Sewage Works Agency
Japan Institute of Wastewater Engineering Technology
Water and Sewerage Works Bureau, Kyoto City Government
Environment and Sewerage Bureau, Osaka City Government
Bureau of Construction, Kitakyushu City Government

FZK:
TUA:
TUDA:
TUDR:
TUF:
TUH:
BWW:
WVB:
FI:
HAG:
SG:
PC:
LURI:

Research Center Karlsruhe
Aachen University of Technology
Darmstadt University of Technology
Dresden University of Technology
Freiburg University of Technology
Hannover University of Technology
Berlin Waterworks
Wupperverband
Fraunhofer Institute
Huber AG
Steinhardt GmbH
Prack Consult Ltd.
LURI Waterssystems Ltd.
- 30 -

別添 3 ワークショップ参加者名簿（英文）German DelegatesDipl.-Ing. Clarisse Harley
Senior Engineer of Prack Consult
Prack Consult Limited
Phone: +49-0481-7557
Email: Prackconsult@t-online.de

Dipl.-Ing. Ralf Steeg
Head of LURI Watersystems
LURI Waterssystems Limited
Phone: +49-030-536-87-60
Email: steeg@spree2011.de

Dr Stefania Paris
Department of Research and Developent
Huber AG
Phone: +49-08462-201-744
Email: ps@huber.de

Prof. Dr Martin Wagner
Deputy Head of the Institute for Waste Water
Technology
TU Darmstadt
Phone: +49-06151-16-2148
Email: m.wagner@iwar.tu-darmstadt.deProf. Dr Johannes Pinnekamp
Head of the Institute for Sanitary Engineering
RWTH Aachen
Phone: +49-0241-80-2-52-07
Email: Sekretariat@isa.rwth-aachen.deProf. Dr Karl-Heinz Rosenwinkel
Head of the Institute for Sanitary Engineering andWaste Technology
UNI HannoverPhone: +49-0511-762-2276
Email: rosenwinkel@isah.uni-hannover.de

Prof. Dr Walter Trösch
Deputy Leader of Fraunhofer-Institute
For Interfacial Engineering andBiotechnology IGB
Fraunhofer Institute
Phone: +49-0711-970-4220
Email: troe@igb.fhg.de

Prof. Dr Klaus Kümmerer
Institute for Environmental Medicine
And Hospital Epidemiology
UNI Freiburg
Phone: +49-0761-270-5464
Email: Klaus.Kuemmerer@uniklinik-freiburg.de

Dipl.-Ing. Jörg Steinhardt
Managing Director of Steinhardt Water Technology
Systems
Steinhardt Water Technology Systems
Phone: +49-06128-9165-15
Email: info@steinhardt.deProf. Dr Peter Wolfgang Gräber
Institute for Wate Management and Contaminated Sites
TU Dresden
Phone: +49-03501-530-029
Email: graeber@rcs.urz.tu-dresden.de- 31 -

Dr Bernd Wiebusch
Customer Relation and Marketing Manager
Wupperverband
Phone: +49-0202-583-141
Email: wb@wupperverband.de

Dipl.-lng. Helmer Prack
Managing Director of Prack Consult
Prack Consult Limited
Phone: +49-0481-7557
Email: Prackconsult@t-online.de

Dr Carin Sieker
Head of Governmental and Environmental Issues
Berlin Water
Phone: +49-030-8644-6129
Email: carin.sieker@bwb.de

Dr Rüdiger Furrer
Project Manager of the Project Management Agency
Forschungszentrum Karlsruhe
FZK - PTKA
Phone: +49-07247-82-3235
Email: Ruediger.Furrer@ptka.fzk.de

Prof. Dieter Fuhrmann
Head of the water technology division of the ProjectManagement Agency Forschungszentrum Karlsruhe
FZK - PTKA
Phone: +49-07247-82-3003
Email: dieter.fuhrmann@ptka.fzk.de

Dr Hans Schmidt-Horix
Managing Director of ETIETI Environment & Trade International GmbH
Phone: +49-05401-3470-11
Email: hans.schmidt-horix@eti-germany.de- 32 -

Japanese Delegates
Mr Motoi NASU
Director for Sewerage Engineering and Development
Sewerage Planning Division, Sewerage and Wastewater
Management Department, City and Regional
Development Bureau, Ministry of Land, Infrastructure
and Transport (MLIT), Government of Japan
Kasumigaseki 2-1-3, Chiyoda-ku, Tokyo 100-8918,
Japan
Phone: +81-3-5253-8426
Fax: +81-3-5253-1596
Email: nasu-m2ij@mlit.go.jp

Mr Makoto Fujita
Manager for Project Assessment and Evaluation
Administrative Division, Environment and Sewerage
Bureau, Osaka City Government
Nanko-kita 1-14-16, Suminoe-ku, Osaka 559-0034,
Japan
Phone: +81-6-6615-7666
Fax: +81-6-6615-7690
Email: mak-fujita@city.osaka.lg.jp

Mr Shuji Tanaka
Director
Water Quality Control Department, National Institute forLand and Infrastructure Management, MLIT
Asahi 1, Tsukuba, Ibaraki 305-0804, Japan
Phone: +81-29-864-2831
Fax: +81-29-864-2817
Email: tanaka-s92ta@nilim.go.jp

Mr Yasumitsu Kondo
Assistant Mamager of Planning
Bureau of Construction, Kitakyushu City Government
Osayuki-nishi 5-14-18, Kokuraminami-ku, Kitakyushu
803-8501, Japan
Phone: +81-93-582-2485
Fax: +81-93-582-3114
Email: yasumitsu_kondou01@mail2.city.kitakyushu.jp

Mr Toshiaki Yoshida
Senior Researcher
Wastewater System Division, Water Quality Control
Department, National Institute for Land andInfrastructure Management, MLIT
Asahi 1, Tsukuba, Ibaraki 305-0804, Japan
Phone: +81-29-864-3343
Fax: +81-29-864-2817
Email: yosida-t92e5@nilim.go.jp

Dr Takao Murakami
Exectie Senior Researcher
Research and Technology Development Department,
Japan Sewage Works Agency
Shimosasame 5141, Toda, Saitama 335-0037, Japan
Phone: +81-48-421-2693
Fax: +81-48-421-7542
Email: murakamit@jswa.go.jp

Mr Mizuhiko Minamiyama
Head
Wastewater and Sludge Management Division, Water
Quality Control Department, National Institute for Landand Infrastructure Management, MLIT
Asahi 1, Tsukuba, Ibaraki 305-0804, Japan
Phone: +81-29-864-3933
Fax: +81-29-864-2817
Email: minamiyama-m92ta@nilim.go.jp

Mr Osamu Fujiki
Research Fellow & Director
1st Research Department, Japan Institute of Wastewater
Engineering Technology
Nishiikebukuro 1-22-8, Toshima-ku, Tokyo 171-0021,
Japan
Phone: +81-3-5951-1331
Fax: +81-3-5951-1333
Email: o-fujiki@jiwet.or.jp

Mr Kiyohiko Hayashi
Director
Toba Wastewater Treatment Plant, Sewerage Department,
Water and Sewerage Works Bureau, Kyoto City
Government
Kamitoba, Tonomori, Umenoki 1, Minami-ku, Kyoto
601-8161, Japan
Phone: +81-75-671-4161
Fax: +81-75-682-2731
Email: k.hayashi@suido.city.kyoto.jp

Mr Shigeru Ikarugi
Researcher
1st Research Department, Japan Institute of Wastewater
Engineering Technology
Nishiikebukuro 1-22-8, Toshima-ku, Tokyo 171-0021,
Japan
Phone: +81-3-5951-1331
Fax: +81-3-5951-1333
Email: s-ikarugi@jiwet.or.jp- 33 -

Mr Kenji Sakai
Deputy Director
Construction Technology Research Department, Public
Works Research InstituteMinamihara 1-6, Tsukuba, Ibaraki 305-8516, Japan
Phone: +81-29-879-0853
Fax: +81-29-879-6748
Email: ksakai@pwri.go.jp

Mr Koya Komori
Senior Researcher
Water Quality Team, Water Environment Research Group
Public Works Research InstituteMinamihara 1-6, Tsukuba, Ibaraki 305-8516, Japan
Phone: +81-29-879-6777
Fax: +81-29-879-6748
Email: komori@pwri.go.jp

Mr Masaaki Ozaki
Team Leader
Recycling Team, Material and Geotechnical Engineering
Research Group, Public Works Research InstituteMinamihara 1-6, Tsukuba, Ibaraki 305-8516, Japan
Phone: +81-29-879-6764
Fax: +81-29-879-6797
Email: ozaki@pwri.go.jp- 34 -

別添 4 会議及び現地調査の写真

写真１ 会議における集合写真

写真４ 雨水滞水池におけるフラッシング

写真２ 会議の一場面

写真５ フーバー社敷地にある処理水再利用公園

写真３ 屎尿分離型便器- 35 -

発表資料INSTITUT FÜR SIEDLUNGSWASSERWIRTSCHAFT UND ABFALLTECHNIKLEIBNIZ UNIVERSITÄT HANNOVER
Prof. Dr.-Ing. K.-H. Rosenwinkel

Municipal wastewater treatment in Germany – state of the art
K.-H. Rosenwinkel, Institute for Water Quality and Waste Management,
Leibniz University of Hanover (ISAH), Welfengarten 1, 30167 Hanover, Germany

Introduction
In the EU the Wastewater Directive is an emission–based regulation which defines required
effluent quality in terms of COD, BOD and nutrient concentration. As various bodies of water (e.g.
the Baltic Sea) are becoming eutrophic, the imission and watershed integrated management
approach is being adopted in EU as well. The new EU water-framework-guideline requires animission-based river-basin-management and a good quality for all river-basins in the EU. The
following will present the technology that is currently used in WWTP in Germany and thedeveloping trends.

Wastewater Treatment in Germany
Table 1 presents the current minimum requirements for effluents from municipal WWTPs whichhave to be met as the yearly mean values. Germany adopted the EU Directive, however theeffluent levels must be met in the qualified peak sample (ABWV, 2004) – a considerable stronger
requirement.
Table 1:Minimum effluent requirements from municipal WWTP in Germany and the EU.
(*) denotes “sensitive areas”,(**) “normal areas”
Minimum requirements FRG in (mg/L)
COD
BOD
NH4-N

TN

TP

<1
1-5

150
110

40
25

-

-

-

5 - 10
10 - 100
> 100

90
90
75

20
20
15

10
10
10

18
13

2
1

Size [1000 PE]

Size [1000 PE]

EU requirements in (mg/L) or as minimum (%) Removal
COD (**)BOD (**)NH4-N
TN (*)TP (*)

10 - 100

125 or 75 %25 or 70 -90 %-15 or 70 - 80 %2 or 80 %> 100

125 or 75 %25 or 70 - 90 %-10 or 70 - 80 %1 or 80 %- 37 -

Seite 2

Typical process configuration
The most commonly used BNR processes in Germany are pre-denitrification and simultaneous
nitrification-denitrification (SND). Plants practicing enhanced biological phosphorous removal(EBPR) typically employ Johannesburg, ISAH or Phoredox type configuration. Other plants use
the cascade-denitrification and the alternating denitrification process.
An example of technology development is provided by Hildesheim WWTP which employs SND
and EBPR. Designed in 1982/1983 the plant was commissioned in 1987. In contrast to the warmand concentrated (BOD of 300-400 mg/L) South African wastewater, where BNR processes
originated, the Hildesheim WWTP at times may have BOD5 as low as 100 mg/L due to infiltrationand combined sewers. The plant is operated using the ISAH process, where the return sludge(RAS) is denitrified in a separate pre-anoxic zone to offset any impact on phosphorus release in
the subsequent anaerobic zone. If necessary, additional substrate can be fed from the anaerobic
primary sludge fermentation tank to the pre-anoxic zone. Initially operated as two parallel lines,
the plant had all four passes commissioned in 1997 (Figure 1).

effluent

return sludge

Figure 1: Flow sheet of the Hildesheim WWTP (with digester and EBPR in a fullstream)

The average effluent concentrations in 2001 were 0.12 mg TP/L and 4.0 mg TNmin/L (80%cumulative frequency concentrations: 0.26 mg TP/L and 6 mg TNmin/L), well below the permit
requirements of TN<10 mg/L and TP<1 mg/L (Figure 2). Although chemical precipitation wasavailable the low effluent TP values were almost entirely the result of the biological phosphorus
removal. Plants in Germany benefit from significant financial savings in mandatory wastewater
charges when treatment effects exceed the permit requirements.

- 38 -

Seite 3
P O 4 -P [ m g /l ]0

0 ,1 20 ,20 ,2 6

0 ,4

0 ,6

0 ,8

1

1 ,2

1 ,4

100%

100%

90%

90%

80%

80%

P O 4 -P

70%

70%

60%

60%

N min

50%

50%

40%

40%

30%

30%

20%

20%

10%

10%

0%

3 ,9 80

2

0%

5 ,9 8

4

6

8

10

12

14

16

18

20

N m in [ m g /l]

Figure 2:

Cumulative frequency for the parameters Nmineral (NH4-N + NO3-N) and Ptot in theeffluent of the secondary clarifiers at the Hildesheim WWTP as daily average 2001

The WWTP Husum is an example of a process with SND and biological phosphorous-removal ina sidestream. The side-stream process called the CISAH-Process, consists of anaerobic tanks,
stripper and an optional lime precipitation. The flowsheet of the WWTP Husum is represented in
Figure 3.

Figure 3:

Flow diagram of Husum WWTP without digester and employing SND and side stream
biological-chemical phosphorus removal

The effluent concentrations in 2004 were TP (80%)= 0.17 mg/L without precipitation, and TNmin(80%) = 2 mg/L, averaging (50% data) 0.12 mg TP/L and 1.7 mg TNmin/L. The extremely low
nitrogen concentrations were due to the high COD/N ratio (Table 2). At Husum the SRT is 15.1

- 39 -

Seite 4days in 2004 and the ratio COD/N is 16.2, at the WWTP Hildesheim the SRT is 16 d and the
COD/N ratio is 15. The influent-concentrations of the WWTP Husum are much higher than that of
the WWTP Hildesheim due to industrial influences. In comparison, for another WWTP HannoverGümmervald (approx. 750,000 PE) with a COD/N ratio of only 11.5, the effluent-data of
2001/2002 for the 50% cumulative frequency are 6.6 mg TNmin/L and 0.5 mg TP/L (MAKINIA ET AL
2005). These figures show the important influence of the COD/N ratio to the nitrogen-effluent
quality, in special for nitrate. Table 2 shows the N-effluent concentrations for the three WWTPs
named before, in relation to the COD/N-ratio and the sludge age.
Table 2:

Impact of COD/N in three German plants on effluent total nitrogen concentrations

Capacity

SRT

COD/N

TNmin effluent concentrations

WWTP[1000 PE]

[d]

[-]

50% [mg/L]

80% [mg/L]

Hildesheim

approx. 240

16.0

15.0

4.0

6.0

Husum

approx. 110

15.1

16.2

1.7

2.0

Hannover-Gümmerwald

approx. 750

16.0

11.5

6.2

8.2

Trends in Germany and EU
Integrated River Basin Management
The emphasis in EU begun to shift from the emission to the imission-based approach to water
quality management. This calls for a more integrated, system-wide approach that includes all
sources of pollution within a watershed and within an urban jurisdiction, including sewerage,
treatment plants and the receiver. Germany was one of the first to establish the river watershedwater quality management system such as for the river Ruhr (Ruhrverband). Recently, urban
watersheds became targets with attempts to direct as much as possible of the combined sewer
overflows into the wastewater treatment plants.
As an example, a case study is presented in which the research in a calibrated model focusses
on the influences of different ratios between rain- to dry weather flow on the total emission fromthe effluent of the treatment-plant and the combined sewage overflow (CSO). In case of a heavy
rainfall event high loads are discharged via combined sewer overflows into the receiving waters.
Currently, the usual remedy is the construction of stormwater tanks with overflow; however, thismethod requires large tank volumes and high construction costs. A partial relief from this negative
impact could be offered by utilizing the existing capacity of the WWTP to process the CSO andthus reduce total emission from the sewer system and the WWTP. This could be achieved by
optimization of the available plant capacity with model-based control strategies. Figure 4
describes the area of interest, with the WWTP, the stormwater overflows and the receiving waters
as the focus of attention.

- 40 -

Seite 5

combined / separate system

combined system

Receiving waters

SeweragesystemStorage +Treatment•Simulation

Undocking / Percolation
Use of storage
capacity• Immission

Area of examination

Sewer cleaning• CODsewer ≠ CODeffluent

max. Q?
• Simple balance(NH4 + COD-Load)

Local/Central
control• Reduction emission

WWTP
Optimised operation WWTP in caseof rainfall (MSR, Online-Simulation)

Figure 4:

Area of examination in the urban drainage area and the boundaries for total emission
from WWTP and CSO

The results of the research show that the increase of use from WWTP capacities will lead to
reduction of the total load (e.g. of NH4-N) to the river (SEGGELKE, 2002). The high and highlyvariable WWTP influent loads in case of stormwater necessitate optimisation of control andoperation. Apart from conventional control strategies which are adapted to the situation
stormwater, observation mechanisms with continuous monitoring of the status of the biologicalprocess become necessary. Predictive adaptive control systems, consisting of an on-line coupledmodel and an implemented prognosis calculation tool could determine the maximum possible
loads to the inlet of the WWTP and the optimal utilisation of the capacities while meeting theeffluent values.
Following, the results from the theoretical calculations of the total emission of sewer system andWWTP are shown in Table 3 (focus is on COD and KN). Based on scaled-up results (actual
effluent concentration, fictitious water quantity) of a pilot plant study for a WWTP (73,500 PE), theemissions are calculated under specification of different inflows to the WWTP with thehydrological sewer model KOSIM (SEGGELKE, 2002). The table presents the load reduction
compared to the calculation with the storage volume 8.940 m³ (German ATV A128 design
guideline) in case of storm flows as high as twice of the dry weather flow and keeping the limiting
values of the EU-guideline in case of higher inflows. For reasons of simplicity the concentration of
CSO were assumed to KN = 20 mg/L and COD = 140 mg/L (SEGGELKE AND ROSENWINKEL, 2002).
Table 3:Comparison of the loads from CSO + WWTP and the load reduction for different
combined flows to the treatment plant

Influent(%) DWF

load from total area [kg/a]

load reduction

KN

COD

KN

COD

200

12,95090,600

-

-

300

9,250

64,70013.8 %

8.4 %

400

6,970

48,80022.2 %

13.5 %- 41 -

Seite 6
In the comparison, the reduction of harmful CSO peaks in the receiving waters is neglected. The
example shows a reduction of the KN load of 22% to the river in case when the WWTP inflow isfour times the dry weather flow i.e. instead of the German standard (2 Qdryw). The most important
influence is given for the Ammonia-reduction, this can be reduced effectively only by a biologicalsystem.
Plant Wide Modeling
As an important tool for the development, the evaluation of novel control and operation concepts,
simulation is widely used. One main focus of the works is the modelling on a plant-wide level
including processes for sludge treatment energy consumption/production besides the classicalactivated sludge process. One main aspect in sustainable operation is the consideration andexamination of each relevant emission path. In reference to waste water treatment plants action
with the goal of an optimisation of effluent loads also must be analysed on the implicated effects
on the sludge digestion and the coupled energy production.
For the expansion of the common models of activated sludge systems for the use in plant widemodelling different additional models are necessary including the mechanical pre-treatment (grids,
primary clarification, pre-precipitation etc.), the biological/chemical step with a broad diversity oftechnologies (activated sludge and biofilm systems, sequencing batch reactors, chemical
precipitation, etc.); the sludge treatment (mechanical thickening, anaerobic digestion, drying,incineration) and the energy production and consumption (gas engines, block heating works,
aeration devices, etc.) (ROSENWINKEL, SPERING, 2006).
In addition to the integrated consideration of the treatment-plant and the combined sewage
overflow (CSO), the several currents have to be eliminated. The co-treatment of waste by kitchendisrupters together with sewage can be one example (WENDLER, 2005).
New treatment technologies
Overall removal efficiency shows significant decline in effluent concentrations in Germany (Figure5), mainly due to improved plant design, novel processes and better operation. Significant inroadsin activated sludge treatment are being made in EU by the biofilm technologies. Some 40 plants
with biological filtration operate in Germany today, treating effluent from 1.5 million PE. The plants
use biofiltration for nitrification and also for denitrification. The reactors include aerated
submerged-bed upflow filters, downflow filters, and continuously or discontinuously backwashedfiltration. The effluent suspended solids concentration of filtration units, following conventional
final clarifiers are below 5 mg/L, the nitrogen concentrations in the effluent are covering a wider
scale, depending on variations of inlet flow and composition, mode of operation, e.g. dosage ofexternal carbon.

- 42 -

Seite 75045Concentration

40
35
COD g/m³
BOD g/m³
NH4-N g/m³
Ntot g/m³
Ptot g/m³

30
25
20
15
10
5
0
1994

1996

1998

2000

2002

2003

Year

Figure 5:

Mean yearly effluent concentrations of German plants (DWA 2003)

Increasingly stringent nitrogen standards call for separate treatment of sludge processing liquors
using physical, chemical and biological methods. In a few cases, the nitrogen load is decreased
by incineration of raw sludge, e.g. at Vienna or Berlin.
The membrane bioreactor (MBR) technology begins to be implemented more often and for larger
facilities. In the MBR the secondary clarifier is replaced by a membrane module yielding highclarity final effluent. Smaller reactor volumes are typically the result of higher contents of MLSS
(up to 15 g/L and above) in comparison to standard activated sludge systems. Today 40 MBR
plants operate all over Europe, with 16 of them in Germany. The capacities vary from 150 to
200,000 PE. The technology promises to reduce the suspended solids to zero and to minimise a
lot of harmful substances in the effluent (e.g. endocrine disrupters and pharmaceuticals).
Of special importance for the evaluation is the fact, that the membrane is only a physicalselection-tool and the reaction is to be done by the biological system. The advantage of theeffluent-quality with meeting the high standard of the EU-bathwater-guideline stands in contrast to
the higher energy demand and the sensitivity against peak-concentrations like ammonia.
Membrane technology has been used in municipal wastewater treatment involving the applicationof polymer membranes for more than 10 years now. Polymer membranes have proved
themselves, despite exhibiting material dependent disadvantages such as limited chemical
stability during cleansing or anti-fouling measures. Ceramic membranes appear to hold significant
potential in this area. An extensive implementation of ceramic tubular membranes (cross-flow) for
wastewater treatment results in high module and operating costs for the operator. Ceramic flat
membranes, which can be implemented in the form of submerged low pressure membranes (TMP
<1 bar) are to be tested as alternatives. Their suitability for the treatment of large-volume
wastewater streams or types of wastewater that are unsuitable for polymers due to their chemical
properties, in combination with a high lifespan of the material involved, facilitates economical
deployment (BRINKMEYER ET AL., 2006).

- 43 -

Seite 8
Deammonification process for the treatment of sludge water
By a separate treatment of the sludge water, the biological stage of a municipal wastewater
treatment plant may be discharged significantly. For sludge water treatment chemical andphysical methods as ammonia-stripping are used as well as biological methods like e.g.
nitrification/denitrification. Typically the sludge water is characterized by high ammonia content
and low COD/N ratio which makes it unfavourable for conventional biological treatment. Fullnitrogen removal by nitrification/denitrification may only succeed by addition of an external carbon
source like acetic acid which leads to high operating costs. With the process of Deammonification
nitrogen can be biologically removed from wastewater with low COD/N ratio without any additional
carbon source.
The Deammonification Process can be described as a process divided into two different steps,
which are performed by two groups of organisms. The first step, the aerobic conversion ofammonia to nitrite is done by bacteria of the nitrosomonas group, for the following, anoxic
conversion of nitrite and ammonia to elementary nitrogen, organisms which are members of thegroup of planctomycetales are hold responsible. Figure 6 shows the application of both steps in a
biofilm.

NH +4
NH +4 + 2 HCO3− + 1,5 O 2 → NO2− + 2 CO 2 + 3 H 2 O

O2 = 0

Biofilm

O2 > 00,5 O 2 + NO −2 → NO3−

NH +4 + NO −2 → 2 H 2 O + N 2*

Carrier*Broda, 1977

Figure 6:

Deammonification in a Biofilm

The members of the planctomycetales group seem not to be able to build up an own biofilm
structure but need an existing biofilm to enrich in. Thus, the first step of starting up
Deammonification is an aerobic operation with high substrate load and adequate aeration which
will result in a mixed biocoenosis containing aerobic and anoxic ammonia oxidisers. In a Moving
Bed-system the thickness of the biofilm is limited by the shear forces caused by intense mixing,
which means build up of anoxic zones for the second step of Deammonification is only possible
by ensuring a low oxygen concentration in the reactor. Another possibility is to divide the twoprocess steps ‘time-based’ by an alternating aeration or ‘physically’ by using different reactors.
To ensure Deammonification it is necessary to perform only the first step of nitrification and notoxidise the ammonia to nitrate but nitrite. Therefore the nitrite oxidising nitrobacter bacteria haveto be inhibited selectively. One possibility to establish nitritation is to completely wash out thenitrobacter out of a system of suspended solids by simply adjusting the sludge age appropriately.
This can be done, because at higher temperatures the growth rate of nitrosomonas is becoming
higher than that of nitrobacter. The point of washing out nitrobacter at e.g. 25°C is at a sludge ageof about 1.3 days. The patented SHARON-system is based on this principle and can be used to- 44 -

Seite 9
easily apply a nitritation system (MULDER AND VAN KEMPEN, 1997). SHARON-reactors already arein operation at several WWTPs. Because the washing out of certain bacteria by regulation of thesludge age is not suitable for a biofilm process, different methods for inhibition of nitrite oxidisers
must be developed, which do not have a negative influence on aerobic ammonia oxidisers. For
example the sensitivity of nitrosomonas bacteria on free ammonia (NH3) is lower than that of
nitrobacter. Thus, nitritation can be established by adjusting the pH value because the balance
between ammonia as NH4 and free ammonia as NH3 is based on the ammonia concentration,
temperature and the pH value. By rising the pH by addition of a base like NaOH free ammonia will
also rise and nitrobacter will be inhibited. The ammonia concentration and the pH will have to beobserved accurately because, if free ammonia rises too much, nitrosomonas also will be inhibited.
Another possibility of selective inhibition of aerobic nitrite oxidisers is based on the different
conversion rates in relation to the oxygen concentration. At low DO, nitrosomonas is growing
faster than nitrobacter so nitrite will be enriched (HIPPEN, 2001). Also an intermittent aeration of anitrification reactor will lead to nitrite enrichment if the aeration time is adjusted appropriately,
because after switching on aeration again, nitrobacter seem to have a „lag-phase“ that is longer
than the one of nitrosomonas (KATSOGIANNIS ET. AL., 2002). This method of discontinuous
aeration is successfully used to ensure nitritation in the full scale plant at Hattingen which is
describe in the following chapter.
In the year 2000 a full scale sludge-water treatment plant was built at the WWTP of Hattingen by
the Ruhrverband, Germany. Within the scope of a research project, the process of
Deammonification should be implemented, using the Kaldnes®-Movig-Bed System. Project
partners were the Ruhrverband, the PURAC GmbH, Merseburg, and the Institute for Water
Quality and Waste Management Hanover. Figure 7 shows the flowsheet of the full-scale plant in
Hattingen.
Q = 200 m3 d-1

pH

pH

pH

BypassRecycle (optional)
V = 684 m3
CNH4-N = 530 mg L-1

Figure 7:

Nitritation / Anoxic Ammonia-Oxidation

Degasification

V = 104 m3
Aeff = 20.400 m2
DO = 0-4 mg L-1

V = 24m3

V = 67m3
Aeff = 13.400 m2
DO = 0-4 mg L-1

V = 67m3
Aeff = 13.400 m2
DO = 4 mg L-1

Flowsheet of the full scale Deammonification at Hattingen (ROSENWINKEL ET AL., 2005)

Some results of the Deammonification Phase are shown in Figure 8. In this Figure the nitrogen
feed for the plant is shown together with the temperature of the wastewater and the load
converted to elementary nitrogen. Maximum performance is at approx. 70-80% converted at a

- 45 -

Seite 10
load between 100-160 kg N d-1 during normal operation. In the beginning of 2004 a reduced
nitrogen elimination of down to 25 kg N d-1 was detected, caused by very low wastewatertemperature and, following, by biofilm loss. Meanwhile by rising the nitrogen load and oxygen
supply, the biofilm thickness has developed again and nitrogen elimination performance hasreached a satisfactory level. In winter 2004/2005 plant performance could be ensured, because
the water temperature did not drop below 20°C due to the installation of a cover to the sludge
water storage tank. Nevertheless the measurement of the biomass cultivated on the Kaldnes®carriers has become one of the most important factors for running the Deammonification plant.

70

5
.0

.0
4

5
.0
.0
2

01

01

.0
.1
2

4

4
.0
01

4
.0

.1
0
01

4

.0
8
01

4

.0

.0
01

4
01

.0
4

.0
.0
2

.0
6

3
.0

.1
2
01

01

.0

3

3
.0

.1
0
01

01

01

.0
6

.0

.0

.0
4
01

.0
2

01

01

01

3

0
.0

0
.0
8

10

3

20

3

20

2

40

2

30

.0

60

.0

40

.1
2

80

2

50

.0

100

.1
0

60

.0
8

120

01

N, Elimination [kg d-1]

140

Figure 8:80

N InletElimination
Temperature

Temperature [°C]160

Overall performance of the full scale Deammonification (ROSENWINKEL ET AL., 2005)

Optimisation of Phosphorus Recovery by MAP Precipitation (Magnesium-AmmoniumPhosphate)
Another trend is the development of techniques for phosphorus recovery, which can be done byrecovery from the liquid phase, from the sludge or from the ash. The stream used for P recovery
is selected based on the recovery potential to be utilised, the acceptable effort for phosphorus
redissolution and the desired quality of the precipitation.
Figure 9 shows the phosphorus balance of a WWTP with enhanced biological P-removal (EBPR).
Approx. 10 % of the phosphorus remain in the effluent and approx. 11% are incorporated in the
primary sludge (Jardin, 2003). The potential of p-recovery from the liquid phase accounts forapproximately 37 %, from digested sludge or ash nearly 90 %.

- 46 -

Seite 11
Influent : 1,9 g/p*d = 100 %Effluent
0,2 g/p*d
approx. 10 %Excess sludge+ simultanuos
precipitationPS

0,2 g/p*d
approx. 11 %0,8 g/p*d
approx. 42 %approx. 53 % in the sludge

Figure 9:

Potential of
p-recovery fromthe liquid phase

0,7 g/p*d
approx. 37 %optimisation

Potential for phosphorus recovery from the liquid phase (ROSENWINKEL ET AL., 2005a)

The recovery from the liquid phase shows in comparison with recovery from digested sludge or
ash the slightest potential. However it is relatively easy to apply and to integrate near-term inexisting plants. Furthermore, processing of the received phosphorus-products of P-recovery by
crystallisation or MAP-precipitation is much easier and without or with only low application ofchemicals. It is thus cheaper than a P-recovery from digested sludge or ash.
In case of plants with enhanced biological P-removal, the goal is to re-extract the phosphorus
stored in the phosphorus accumulating organisms (PAOs). For this, a reactor is placed in the
return activated sludge line. In this reactor an anaerobic phosphorus release is initiated by dosing
readily biodegradable carbon. Through subsequent precipitation and separation, the stored
phosphorus can be recovered and re-used as e.g. fertiliser.
Among optimisation of precipitation the optimisation of phosphorus-redissolution plays a crucialrole regarding to utilise as much as possible potential of phosphor-recovery.
Known measures for optimisation of phosphorus-redissolution are increasing the supply of readily
biodegradable substrate, adjusting the optimum of pH-value and temperature as well as anadequate anaerobic contact time. Considering excess sludge, thickened sludge offers an otherchance of optimisation. Due to a lower flow, less tank volume is needed. Furthermore bydisintegration of the excess sludge by extensive cell disruption more redissolution can beachieved.
The precipitation of phosphate and magnesium respectively as NH4MgPO4 × 6H2O is known in
the analytic chemistry since 1825. In the chemical nomenclature, the hardly soluble salt is named
ammonium-magnesium-phosphat-hexahydrat. In wastewater engineering it is applied for
precipitation of ammonium or phosphorus and it is called magnesium-ammonium-phosphat (MAP)or struvite.
The technical reaction equation of MAP-precipitation results with regard of the chemicallycombined water:
Mg2+ + NH4+ + PO43- + H2O ↔ MgNH4PO4 ⋅ 6 H2O- 47 -

Seite 12
MAP-precipitation is influenced by temperature, supersaturation degree achieved in the reactor
related to pH, Mg2+, NH4+ and PO43- concentrations, and the presence of other ions such as Ca2+.
Uncontrolled precipitation of MAP can produce pipe blockages and problems in the succeeding
aggregates of the dewatering process. However, MAP can be crystallised under controlled conditions. Figure 10 shows an example for a MAP-precipitation unit on a WWTP with EBPR.
P-redissolution

MAP-precipitation
N

C

Mg

effluent

Pdissolved

Sludgeof EBPRsludgeMAP

Figure 10: Flowsheet of a potential implementation of a MAP-precipitation unit on a WWTP with
EBPR

Readily biodegradable substrate, required for P-redissolution, can be obtained from thesupernatant of the acidification of primary sludge. Sludge liquor from plants with sludge digestion
can be used as nitrogen source.
WWTP with anaerobic sludge stabilisation have a higher sludge age and different sludge balance
than plants without sludge stabilisation. It would be interesting to analyse the influence of thisdifferences on the phosphorus recovery.
Anyway, the controlled MAP-precipitation enables EBPR plants to achieve very low levels of
effluent phosphorus concentrations and to recover phosphorus as a product that can be used asa fertiliser.

Conclusions
EU has introduced minimum effluent (emission) standards in 1991 which led to implementation of
biological nutrient removal. The trends in EU and Germany also point towards lowering theeffluent nutrient levels to below those required by EU Directive, leading to lower discharge feesand protection of eutrophic receivers.
In spite of local preferences for a particular BNR configuration, similar tendencies were observedin Germany with the most common process employing anaerobic/anoxic/aerobic configuration
with pre-denitrification, with many plants capitalizing on the simultaneous nitrification and- 48 -

Seite 13
denitrification (SND) and with practicing enhanced biological phosphorus removal (EBPR) in
fullstream or sidestream.
The main new trends in EU and Germany include the integrated river basin management, thedeammonification process for the treatment of sludge water, the optimisation of phosphorus
recovery by MAP and the membrane technology (MBR and ceramic membranes) especially forthe elimination of endocrine disrupters and pharmaceuticals.

References
AbwV (2004): Verordnung über das Einleiten von Abwasser in Gewässer, Bekanntmachung der
Neufassung der Abwasserverordnung vom 17.Juni 2004. BGBI. I S. 1108
Brinkmeyer, J.; Rosenwinkel, K-H.; Binkle, O.; Braun, G.; Gabriel, K.; Nonninger, R. (2006):
Development of a submerged ceramic plate module within the scope of a DBU project, Vortrag
auf der Industrial Water 2006, Dechema, 06.02.2006 in Frankfurt
Broda, E. (1977): Two kinds of lithotrophs missing in nature, Zeitung Allg. Mikrobiol. Vol. 17, No. 6,
pp. 491-493
EU (1991) Rat der Europäischen Gemeinschaften: Richtlinie des Rates vom 21.05.1991 über die
Behandlung von kommunalem Abwasser (91/271/EWG); Amtsblatt der Europäischen
Gemeinschaften Nr. L 135, 1991
Hippen, A. (2001): Einsatz der Deammonifikation zur Behandlung hoch stickstoffhaltiger
Abwässer, Publications of the Institute of Water Quality and Waste Management, University ofHanover Vol. 116
Jardin, N. (2003): Phosphorbilanz bei der Abwasser- und Klärschlammbehandlung In:
Rückgewinnung von Phosphor in der Landwirtschaft und aus Abwasser und Abfall, Tagungsband
zum Symposium am 6./7. Februar 2003 in Berlin
Katsogiannis, A. N.; Kornaros, M.; Lyberatos, G. (2002): Enhanced Nitrogen Removal in SBRs
Bypassing Nitrate Generation Accomplished by Multiple Aerobic/Anoxic Phase Pairs, e21344a,
IWA 3rd World Water Congress, Melbourne, Australia, 7.-12. April 2002
Makinia, J., Rosenwinkel, K. H., Spering, V. (2005) Long Term Simulation of the Activated Sludge
Process at the Hannover Gümmerwald Pilot WWTP. Water Research 39, 1489-1502
Mulder, J.W.; van Kempen, R. (1997): N-removal by SHARON, Water Quality international, IAWQ
(Edit.), March/April 1997, pp. 30-31
Obenaus, F., Rosenwinkel, K.-H., Alex, J., Tschepetzki, R. und Jumar, U. (1999): Components ofa model-based operation system for wastewater treatment plants. Water Science and Technology,
39 (4), 103-111
Rosenwinkel, K.-H., Cornelius, A., Thöle, D. (2005): Full Scale Application of the
Deammonification Process for the treatment of Sludge Water. IWA Specialized Conference,
Krakow, Poland, 19.-21. September 2005

- 49 -

Seite 14
Rosenwinkel, K.-H., Beier, M., Pabst, M. (2005a): Optimierung der Phosphorrückgewinnung aus
der wässrigen Phase mittels MAP, Tagungsband zum 75. Darmstädter Seminar Rückgewinnung
von Phosphor aus Abwasser und Klärschlamm, Schriftenreihe WAR, Band 167
Rosenwinkel, K.-H., Spering, V. (2006): Plant Wide Modeling als Instrument
medienübergreifender Emissionsbetrachtung; 13. Simba Anwendertreffen; 18. bis 19. Mai 2006,
Wernigerode
Seggelke, K. (2002): Integrierte Bewirtschaftung von Kanalnetz und Kläranlage zur Reduzierung
der Gesamtemissionen. Dissertation am Institut für Siedlungswasserwirtschaft und Abfalltechnik
der Universität Hannover, Veröffentlichungen des Institutes für Siedlungswasserwirtschaft und
Abfalltechnik der Universität Hannover, Heft 124
Seggelke, K., Rosenwinkel, K.-H. (2002): Online-Simulation of the WWTP to minimise the total
emission of WWTP and sewer system Water Science and Technology, 45 (3), 101-108
Spering, V. (2006): Plant Wide Modeling von Abwasserbehandlungsanlagen als Teil einer
Gesamtbetrachtung von Stoffeinträgen, Vortrag 18. Norddeutsche Tagung für Abwasserwirtschaft
und Gewässerentwicklung; 2006
Wendler, D. (2005): Erfassung und Behandlung ausgewählter Stoffströme in der
Siedlungswasserwirtschaft, Veröffentlichungen des Institutes für Siedlungswasserwirtschaft und
Abfalltechnik der Universität Hannover, Heft 131, 2005

- 50 -

- 51 -

[mg/l] (**)

[mg/l] (**)--

[mg/l]

Ptot.

90

90

75

5.000 – 10.000

10.000 - 100.000> 100.000

BOD

15

20

20

[mg/l]

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

TNmin = TN mineral (without organic)

COD[mg/l]

Size

TNmin

13

18

-

[mg/l]

1

2-[mg/l]

Ptot.

10 or 70 - 80 % 1 or 80 %Leibniz
Universität Hannover(*) for „sensitive areas“, (**) „normal areas“

10

10

10

[mg/l]

NH4-N

Minimum requirement FRG[mg/l] (*)

15 or 70 - 80 % 2 or 80 %[mg/l] (*)

N tot.

FRG Effluent requirements

125 or 75 % 25 or 70 - 90 %[inhab. equiv.]> 100.000

10.000 - 100.000 125 or 75 % 25 or 70 -90 %[inhab. equiv.]

Size

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Leibniz
Universität Hannover• Moving bed systems• A-B Technology / 2 stage

Total number of municipal WWTP‘s in FRG: 6110

• Biofilter (Nitrification andNitrification / Denitrification)

Biofilm Systems• Phoredox System/Phostrip• ISAH System• Johannesburg System• EBPR (combines with any activatedsludge system)• Membrane bioreactors• SBR-Technology• Sludge stabilisation• Alternating denitrification• Intermittent denitrification• Preliminary denitrification• Cascade denitrification• simultaneous denitrification

P removal

Activated Sludge Systems
N – Elimination

EU Effluent requirements

Requirements EU-Standards
COD
BOD
NH4-N

Typical process configurations

Leibniz
Universität Hannover

Effluent requirements

Institut für Siedlungswasserwirtschaft
und Abfalltechnik- P-Recovery / Energyrecovery

Sidestream Elimination and Recovery:- Deammonification- Biofilm Technology- Membrane Technology

Technology:- Integrated River Basin Management

Management:• Trends in Technology and Management:• Typical process configurations• Effluent requirements

Content42

- 52 -

0

5

10

15

20

25

30

35

40

45

50

1996

2000

Year

1998

2002

combined system

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Leibniz
Universität HannoverPredictive, adaptive control system with an online coupled model
prediction and regulation

Ö continuous observation of the state + prognosis

Ö optimisation of the control strategies

Research approach

Optimised operation WWTP in caseof rainfall (MSR, Online-Simulation)• Reduction emission• Simple balance(NH4 + COD-Load)

Surplus Sludge

4

10

11

5

13

12

1

TS, O 2 , pH

Institut für Siedlungswasserwirtschaft
und AbfalltechnikÖPlausibility Control of the Modell-inputÖDefault Value strategyÖSetpoint tracing=> Continous simulation WWTP

WWTP-Online
Simulation(SIMBA-Process)

6

IDM

Inlet

Simulation
sewer
Generate
Inflowscenarios

Rain:meassure +forecast

Leibniz
Universität HannoverPredictiveSimulation

Rain? =>Start

Leibniz
Universität Hannover

DN

RS-

P

Bio -

P

Bio -

NH 4 -N, NO 3 -N, PO 4 -P

2 x NO 3 -N, O 2

7

8

15

14

9

16

17

Simulation WWTP
Calculation of
influent max. Q

current state of
the Modell

measured data from WWTP

Predictive Control Strategy using simulation

ls

can’t be excluded in case of rainfall

max. Q?

• CODsewer z CODeffluent

3

2

O2

Returnsludge

OutletInstitut für Siedlungswasserwirtschaft
und Abfalltechnik

IDM

IDM, TS

6

8

Simultaneous N – Elimination and EBPR in a fullstream

WWTP Hildesheim

o

WWTP

Local/Central
controlÖ significant reduction of the emission

Area of examination• Immission•Simulation

Receiving waters

7

OutletSecondary settlerCÖ but: exceeding of the limiting values

Sewer cleaningÖ inflow WWTP > 2 Qdryweather

Use of storage
capacity

Storage +Treatment

combined / separate system

Undocking / Percolation

Seweragesystem

COD g/m³
BOD g/m³
NH4-N g/m³
Ntot g/m³
Ptot g/m³

Leibniz
Universität Hannover

2003

Integrated River Basin Management

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

1994(Source: DWA 2003)

Mean yearly effluent concentrations of german WWTP‘s

European Water Framework Directive:
Ö imission based approachÖ river water quality management
Ö integrated systemwide approach
Case Study

Aim

Concentration

Full Scale Experiences

.
äd
Pr
ro
nt
gy
te
a
tr

Width: 110 mm

800/300/200/80/
50 nm¾ 3 aerator tubes forcross flow

¾ 3 x 25 cm plates

surface¾ 0.172 m² active filtering

Laboratory module

Institut für Siedlungswasserwirtschaft
und Abfalltechnik¾ Pressure resistance > 10 bar¾ Membrane material D-Al2O3¾ Pore size

¾ Internal channel 21 units,  3 mm

Thickness:
6.5 mmStandard
length 250
mm

Nanopore£ -ModelF 21/30/1100

Laboratory Tests

Institut für Siedlungswasserwirtschaft
und AbfalltechnikÖCasestudies-simulation with calibrated modelsÖControl by measurements sewer, WWTP, river

Laboratory system

Leibniz
Universität Hannover

Leibniz
Universität Hannover¾Capacity of 0.11 to 1 m² offiltering surface¾Fully automatic process
management & data
recording¾45 l activated sludge tank2) Integrated view: influence on river (Optimisationpotential)

1) Online-simulation WWTP + prognose-simulation plant + sewer

Phase 2: fullscale plant (KA Hildesheim)(ASM 2d)

Ö Very good results for longtime simulation

developedÖ MSR-concepts for rainwether conditions

Ö Capacity up to 4 Qt (critical: Nitri + final clarifier)results:

69.6

55.1

39.1

0

100

100.1

123.6

160.7

150

69.1

NH4-N-Fracht
KA WWTPund Kanal [kg]Ammonia-load
CSOaus
plus

50

125.0

From laboratory to pilot system at the municipal wastewater treatment plant

04Institut für Siedlungswasserwirtschaft
und Abfalltechnik

0

25

50

75

100

125

150

175

200

8

12

12

10

16

20

24

28

32

40

44

48

Betriebszeit [d]

36

56

60

64

68

72

76

80

Leibniz
Universität Hannover

52

84

Good comparability of laboratory values¾ Permeability after 80 days: 30 l/m²hbar¾ TMP= 300 mbar

¾ TS= 2-5 g/l¾ 4 m² filtering surface

250

+14 %

0%

+5%

+18 %

Leibniz
Universität Hannover200

194 kg

170 kg

179 kg200 kgSumme: zu IST:

Municipal wastewater pilot system

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

2*Qs+Qf

3,2 x Drywetherflow

3.2*Qs+Qf IST

4*Qs+Qf

6.2*Qs+Qf

2) Test of Online-simulation

NH4-Fracht KA

Heavy Rainfall
Starkregenereignis
30.6.2001

NH4-N-load from Sewer and WWTP (Simulation results)

Trends: Integrated River Basin Management

NH4-Fracht MS

1191) Influence of increasing Q, optimal MSR-strategy etc.

Phase 1: „pilot-scale plant“ ( Hannover-Gümmerwald)

Research project ISAH (founded BMBF)

Permeabilität, normiert 20,0°C [l/m²h bar]

- 53 -

- 54 -

O2

Q

O2

O2

O2

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Fluidised Bed

O2

Q

Rotating Disc React.

Q

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Moving Bed

Trickling Filter

Q

Biofilm Technologies

Q

Leibniz
Universität Hannover

Leibniz
Universität Hannover

Biofilter

O2

Q

15

Q

Submerged Fixed Bed

O2

13

Leibniz
Universität Hannover

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Leibniz
Universität HannoverFull scale plant at Hattingen

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

14

16

NH4  NO 2 o N2  2H2O

NO 2  org. C o N 2

Deammonification
NH4  O 2 o NO 2

Denitritation

NH4  O 2 o NO 2

NO 3  org. C o N 2

NH4  O 2 o NO 2

Nitritation

Denitrification

Nitratation
NO 2  O 2 o NO 3

Nitritation

Biological Nitrogen Removal via Nitrite

Deammonification

40

15
10
5
0

40

20

0

20

25

30

35

45

COD removed

Nitrogen In

50

Nitrogen removed

Temperature

60

80

100

120

140

160

180

Leibniz
Universität Hannover

Renewable Energy
Sources Act

not reported

heating energy (incl. wood)electricity

heat energy and electric energy

0[BMU, Mai 2006]

2000

4000

6000

8000

10000

12000

Leibniz
Universität Hannover

90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05
19 19 19 19 19 19 19 19 19 19 20 20 20 20 20 20

0

10000

20000

30000

40000

50000

60000

70000

80000

Real production of biomass energy inGermany

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

heating energy [GWh/a]Anaerobic Digestion of Wastes and Energy crops

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

02 .02 .02 .03 .03 .03 .03 .03 .04 .04 .04 .04 .04 .05 .05 .05
8.
0
2
2
5
7
9
2
2
4
7
9
1
1
4
6
.0 0.1 9.1 7.0 8.0 7.0 5.0 4.1 2.0 2.0 1.0 9.0 8.1 7.0 7.0 6.0
1
0
1
1
2
0
1
2
0
1
2
0
0
1
2
0
1

Nitrogen-Load,
Elimination [kg/d]

Nitrogen-, COD-Elimination over the full scale Plant

electricity [GWh/a]- 55 -

Temperature [°C]1917

Leibniz
Universität Hannover

0,8 g/p*d
approx. 42 %optimisation

0,7 g/p*d
approx. 37 %Potential of
p-recovery fromthe liquid phase

Institut für Siedlungswasserwirtschaft
und Abfalltechnik• KREPRO bzw. Kemicond process• Aqua Reci process• PHOSTRIP process• SEABORN process• Recovery from anaerobic digested sludge

Leibniz
Universität Hannover• Recovery from Surplus-sludge PRISA Process (MAP precipitation)

approx. 53 % in the sludge

0,2 g/p*d
approx. 11 %PS

Excess sludge+ simultanuos
precipitation

0,2 g/p*d
approx. 10 %Potential of phosphorus recovery in plants with EBPR
Influent : 1,9 g/p*d = 100 %Effluent

Phosphorus Recovery

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Design of the Mixing Facilities R1 & R3

20

18

- 56 -

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Leibniz
Universität Hannover

23

21

Leibniz
Universität Hannoverwww.seaborne-erl.de, 2006

RGU – Regenerative Gas Upgrading

NRS - Nitrogen Recycling System

Pilotplant Owschlag SLH
Fullscale plant Gifhorn NDS

RoHM - Removal of Heavy Metal

SEABORN process

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

MAP precipitation in digested sludge pipes

Mg

MAP

Leibniz
Universität HannoverConclusions and final remarks

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

sludgePdissolved

N

MAP-precipitation

Institut für Siedlungswasserwirtschaft
und Abfalltechnik

Leibniz
Universität Hannover

22

24

effluent• Minimum Requirements for C/N/P are fullfilled in germany• Applications of different Technologies for N and P-removal are in
operation, most activated sludge, but also biofilmtechnologies• Integrated Management of sewer and WWTP is nessecary for
optimisation costs and efficiency• Membranetechnology gives chances to improve the hygienic aspects in
the riverquality• Sidestreamtechnology for deammonification is a efficient application of
biofilmtechnology• Energyrecovery from waste and sludge is efficient, energyproduction
from crops must be validated, the competition to the food production inagricultural area must be very carefully observed• Future technology must consider harmful substances, endocrine
disrupters and personal careproducts

Sludgeof EBPRC

P-redissolution

Optimising MAP precipitation

- 57 -

Institut für Siedlungswasserwirtschaft
und Abfalltechnik
Leibniz
Universität Hannover

THANK YOU FOR YOURATTENTION

Final

25

A century-long strategy for wastewater-system management in Japan;
concept shifts from Wastewater System to The Road Toward Recycling
Society
TANAKA Shuji*, NASU Motoi***Water Quality Control Department, National Institute for Land and Infrastructure Management,
Ministry of Land Infrastructure and Transport, *Asahi1, Tsukuba city, Ibaraki, 305-0804, Japan.
tanaka-s92ta@nilim.go.jp**Sewerage and Wastewater Management Department, City and Regional Development Bureau,
Ministry of Land Infrastructure and Transport, Kasumigaseki 2-1-3, Chiyoda-ku, Tokyo, 100-8918,
Japan. nasu-m2ij@mlit.go.jp
Abstract: When we entered into the 21st century, we noticed many changes in various fields, such as
meteorological change on a global scale, the soaring price of crude oil, frequent droughts and floods, overt
heat-island phenomena in big city areas, a falling birthrate and a rapidly aging population. These changes are
not temporary mutations, but are transformations based on long-term trends that we cannot ignore to plan andre-imagine the future state of wastewater systems. Starting from such understanding of present circumstances,
we have formed a new concept of the role of wastewater systems: to make them the key infrastructure of arecycling society as a national strategy. This is ³The Road toward Recycling Society.´ This paper describes the
new concept of The Road toward Recycling Societyalong with its implementation policy.
Keywords: Recycle, the 21st century, wastewater system policy, improvement of systems
Introduction
Looking ahead to the 21st century, we can predict great changes that will emerge in many fields in Japan. We
must change our living systems to prepare for the future. Our systems consist of many sub-systems. A
wastewater system is these, but one that plays an important role in keeping our society healthy andcomfortable. This means that we need to have a new concept adapting our society to future situations. To set a
new concept and policy for both wastewater systems and wastewater works, a special committee wasconvened and it carried out intense discussions for about one year, announcing its conclusion in a report titled,
Wastewater System Vision 2100. The subtitle of this report is From Wastewater System to The Road toward
Recycling Society as a100-years strategy. This paper describes this new strategy and new concept of The
Road toward Recycling Society.
A new concept of wastewater systems adapted to the 21st century
Among these future changes, serious ones that we will face in the latter part of the 21st century may include
climate change caused by the greenhouse effect and shortages of natural resources such as the fossil fuels, oiland natural gas. These changes will be caused by our lifestyle in the late 20th century, a period of mass
production and consequent mass waste-production. In recent years we already suffered from abnormal
climate that has caused terrific flooding, unusually hot summers and abnormally heavy snowfalls. Another1- 59 -

precursor of future problems is the present historically high oil prices. When these difficulties become
extreme, our lives will be threatened by these problems. In view of this, we must change our society to asustainable one that can achieve future prosperity.
Other problems in Japan that we will face in the relatively near future are social problems caused by ourdecreasing population. Although the decline of our population was predicted and in fully recognized arelatively long time ago, it was a great shock for Japan when the regular census showed an actual reduction of
the population last year. This reduction is due to the recent low birth rate that is actually below the death rate.
On the other hand, life expectancy in Japan is high. One consequence of these conditions is an aging society
and structural changes in both industry and economy. In the aging society, government will have smaller
resources to provide new infrastructure than it does now, so we need to prepare for the future at an earlystages.
Along with these future changes in the natural environment and society, we also wonder about the direction of
future society. In this respect, wastewater systems also must change so we can create a bright future. We needto have a clear image of wastewater systems that provide new functions and play new roles in the 21stCentury as key infrastructure for a better world, by freeing ourselves from conventional images of thesesystems. From these perspectives, our vision of wastewater systems for the 21st century should focus on threegoals: a beautiful environment, safe community and vigorous society. The crucial question we must answer torealize these three goals is how our wastewater systems will contribute to new era. By contemplating these
conditions, we have created a new concept of the 21st century wastewater systems as ³The Road toward
Recycling Society´ to provide a new strategy for the central government.
Besides the above-mentioned future problems, we are already struggling to resolve problems in our fields.
Some of these are categorized as water problems and others as facility management problems. One example
of a water problem is the quick run-off of storm water and another is the drying up of waterways in the dry
season. These cause frequent flooding and environments with reduced amenities. These phenomena arecaused by the reduction of the permeable area in our communities. Another water problem is instability ofwater resources: the inability of big cities to secure their water resources within their water basins for example.
These are not sustainable situations in terms of water resources. A typical example of a facility-managing
problem is the aging of facilities. This not only raises the demand for rehabilitation works and thereby
increases budget needs, but also increases road deterioration such as sudden cave-in caused by corroded
sewers. The new policy also accounts for these present problems.

2- 60 -

Figure 1. Schematic image of the role of wastewater system in 21st century society. Awastewater system is
infrastructure with a key role in sustaining a limited resource society.
What is The Road toward Recycling Society?
The term, The Road toward Recycling Society, implies not only the venous system but also the arterial system
including the heart that function as key organs in the circulation of necessary materials and the transportationof waste in humans. In another words, The Road toward Recycling Society suggests that wastewater systems
become key facilities in hydrologic circulation and resource cycles. This concept aims to replace the20th-century-type wastewater systems with a new kind of system, and also seeks new functions and imagesof systems for the 21st century. And specifically from the viewpoint of the healthy circulation of resources, thecommittee¶s discussions of wastewater systems extend to basic questions: what is wastewater system, whatkind of substances should we collect and not collect with such a system, how can we recover and reuse thecollected substances, and how we create healthy recycling systems in our society? Based on ourreconsideration of these matters, the following three key sub-concepts were presented to achieve the main
image or metaphor of The Road toward Recycling Society:-

Creation of NewWater Passages,
Creation of NewResource Passages andRevitalization of the Systems.

The first sub-concept, Creation of New Water Passages, means the creation of new water-networks andpassages to exploit the manifold functions of water in the field of wastewater works. The second sub-concept,
Creation of New Resource Passages, refers to active efforts to recover resources, such as bio-solids or3- 61 -

nutrients, followed by supplying recovered resources. This sub-concept also includes exploiting land sites ofwastewater works to create new energy ---solar power, wind turbine, and micro-hydro-power generation--- toend our dependence on oil. The third sub-concept, Revitalization of the Systems, differs from the previous twoconcepts in that it supports them, but includes more active meanings of upgrading existing facilities to meetthe social requirements of wastewater works.

Figure 2. The relationships between the main concept and three sub-concepts
The Creation of New Water Passages and development of this policy
The Creation of New Water passages implies recovering healthy water cycles in basin areas by improving
wastewater systems. This will be attained by evolving the following three core-ideas:-Thoroughly recycle and reuse stored rainwater, purified wastewater and incoming ground water in thesystems,-Optimize facility locations to aim for water reuse and-Redesign facility structures so they are suitable for reusing water.
Healthy water cycles will be realized by encouraging infiltration of storm water into the ground accompanied
by reusing stored storm-water and treated-wastewater. Storm-water infiltration can be realized by designing
storm -water systems based on infiltration first instead of draining first. Along with the infiltration first policy,
the introduction of storm-water storage facilities to systems will stimulate the increased reuse of water. Direct
reuse of treated wastewater should also be promoted by introducing advanced treatment.
Storm-water utilization and treated-wastewater recycling may require facility configurations and locations that4
- 62 -

differ from those now in uses. Although the conventional way of deciding the location and capacity of atreatment plant is to consider how effectively we can collect wastewater at the plant, its location and capacity
should be decided according to the demand for water. Determined in this new way, its location and capacity
may be greatly different those of existing plants. The same idea should also be applied to storm water systems.
Considering how effectively we can create a recycling system facilitates the reorganization and rehabilitationof water networks.
The structure of storm water systems may also be transformed when we introduce the new concept to thedesign of structural details. For example, changing storm water drains to open channels from pipe systems
and applying percolating structures and ecologically friendly configurations, in another words, near natural
systems and nature friendly systems.
The Passage for Resources and development of this policy
The Passage for Resources aims to recover resources through wastewater works and thus supply recoveredresources to communities. Introducing this scheme is intended to release less global worming gas fromwastewater systems by promoting energy saving in the systems and by boosting the use ofgreenhouse-gas-free energy such as biomass energy by local communities.
This will be realized by following three ideas:-Realize self-supporting in energy use by treatment systems,-Become a top runner in the application of new-energy by wastewater works and-Supply energy & resources actively to local communities from wastewater works.
These three ideas need to be explained more specifically. The first idea, realizing self-supporting energy use
by treatment systems, aims to promote energy saving, produce new energy in the systems, and then attempt tooperate the facilities independent from external energy supplies. The second idea, becoming a top runner in
new energy, proposes that wastewater works be a top runner in new-energy use and production. The third idea,
supplying energy & resources that are recovered from wastewater woks to local communities, is intended totransform wastewater works into energy and resource centers.
The Revitalization of the Systems and development of this policy
The Revitalization of the Systems proposes effective maintenance of existing facilities and improvement of thesystems to support the two other sub-concepts, Creation of New Water Passages and Creation of New
Resource Passages. Basic policies for realizing this concept include the following three ideas:-Transform maintenance policy from reactive to preventive type,-Improve facilities to meet social demands including multi purpose usages and-Integrate new facility constructions and maintenance works into asset management.
For these purposes, the actual applications of the following three work categories are considered: works toensure safety, works to exploit facilities and works to improve functions. ³Works to ensure safety´ suggests
proactive measures to prevent accidents caused by poor maintenance works such as road cave-in caused by5- 63 -

corroded pipes, to install earthquake resistance configurations into the systems, and to provide evacuationsites for the local communities. ³Works to exploit facilities´ means promoting the multipurpose usage ofexisting facilities. ³Works to improve functions´ implies not only simply improving facilities but also active
management in accordance with the overall review of system plans including reviews intended to realize the
new concept, Road toward Recycling Society.
Conclusion
The 21st century will be an era when we will face many difficulties related to the shortage of resources andclimate changes. To cope with theses situations we need a new concept and policy for our wastewater systems
to mitigate their impacts. As the new concept for 21st century wastewater systems, The Road toward
Recycling Society has been proposed based on one-year committee discussions. The new concept is divided
into three sub-concepts that are Creation of New Water Passages, Creation of New Resources Passages, andRevitalization of the Systems. Each sub-concept includes specific policies to promote actual works. We havejust begun to evolve wastewater works based on this new concept. Therefore, the actual promotion is limited
at this moment but we hold great expectations that in a future, it will be a key infrastructure of the recycling
society.
References
Ministry of Land Infrastructure and Transport: Report on Wastewater System Vision 2100; The Road toward
Recycling Society (in Japanese). September 2005.

6- 64 -

- 65 -

• Frequent flooding due to quick runoff of storm
water• Dried up of waterways in dry weather period• Changing global climate• Reducing amenity on water environment• High energy cost due to diminishing fossil fuel• Increasing aging facilities• Requirement of high reliability on systems• Decreasing populations and aging society• Great deficit on central and local government

Problems about wastewater
system management

3

1

Water Quality Control Department, National
Institute for Land and Infrastructure Management,
Ministry of Land Land Infrastructure and Transport

TANAKA Shuji

A Century–long Strategy
for Wastewater-System Managementin Japan;
Concept Shifts
from Wastewater Systems
to Circulation Passages

June 29, 1999 : FukuokaFukuoka-city, 77mm/hr

42

- 66 -– Reduction of peak flow
– Restoration of dry weather flow instreams• Storage and infiltration first policy– Climate change– Increasing runoff due to increasing
impermeable area and dried up in dry
weather• Managing difficulty on drainage firstpolicyChanging storm water
management policy

7

5July 19, 2003: FukuokaFukuoka-city, 99mm/hr, Total 361mm

urban areas

Total length: about 14,800km

1,827km, 12.4%

open channel,

landscaped

Non-

87.4%

conduit/pipes,
12,904km,

coverd38km, 0.2%

Landscaped
open channel,

Storm water drains & channels in(more than 50mm/hour)Frequency of high intensity of rainfall

86

- 67 -

rni
retu

ng

9

– Open channel, ecology concern, near nature
structure• Redesigning of facility structure for easy
reusing– ReusingReusing-oriented location planning• 100% recycling– Stored rain water, treated wastewater• Optimization of facility location for reusing

11

Creation of Water Passages

An existing treatment plant

ge
Slud

P

A new satellite plant

Satellite plants near demandingsite of reusing water

19,035 kwh/day

90 %

16,616 kwh/day

4,620kwh/day

Garbage &woody refuse

12

Total power generation

5,396kwh/day

6,600kwh/day

Consumption of power

Wind & Solar

Digested Gas

A trial calculation for self supplying of
power in a 50,000 m3/day plant

10

An example of recovered waterways by treatedwastewater in suburban area of Tokyo- 68 -

1310kwh/d for revenue
13

15– Supplying biomass energy for local communities– Wind turbine and solar energy generation• Supplying energy and resources tocommunities– Biomass center collecting kitchen garbage andwood refuse• A toptop-runner of new energy user

– 100% selfself-supplying energy for treatment• SelfSelf-supporting in energy use

Creation of
resource passages

3160kwh/d

1850kwh/d for internal use

Power generation by wind turbine 660kw X0.2X24h=3160kw/dConsumption of electricity 1850m3/d X 1kwh/m3=1850 kwh/d
kwh/dWindWind-turbine capacity 660kw

ODOD-plant capacity 1850 m3/day

in a small scale plant

all necessary electricity

A wind turbine can supply

Bio-solid
fuel

14

Power
plant

by sewer collapse

16

The numbers of cave-ins on roads

Bio-solid

Bio-solid-fuelfactory

Bio-solid-fuel product works

- 69 -

Years old17

<5 <10 <15 <20 <25 <30 <35 <40 <45 <50 50<

19– Rehabilitation and new concept adaptation• Integration of facility construction andmaintenance by asset management
policy– Artificial ground over plants, fiber opticalcables in sewers, etc• Multi-purpose use of facilities– Quake, collapse, blackout, etc• From reactive to preventive maintenance

Revitalization of the systems

0.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

Aged pipes tends to make problems

Collapes/1,000km

Circulation Passages

Creation of New
Resource Passages

Creation of New
Water Passages
Revitalizationof the Systems--Supporting infrastructure for sustainable society--

20

18

Reactive maintenance vs. Preventive maintenance- 70 23

• Circulation Passages=‘Junkan-dou’= ‘Junkan no michi’in Japanese• Wastewater systems =‘Gesui-dou’ in Japanese

From wastewater systems
to circulation passages

21

22• 24 million of unun-serviced population• Requirement for high reliability on
systems• Reducing amenity on water
environment• Weakening financial backgrounds• Increasing stocks of facilities• Changing global environment,
reducing resources, and energy
problems

24

Problems in wastewater work field– Water recycling– Resource recovering– System restoring upon new
concept• New policy for century longtargeting to be circulationpassages

Conclusions

- 71 -

– Climate change by greenhouse gas– Shortage of fossil fuels– Huge waste production– Decreasing of population– Aging society• Emerging problems in the new century

25– Quick runrun-off of storm water– Drying up of waterways– Instability of water resources– Aging of facilities– Huge deficit on central and local governments• Existing problems

The 21st Century

29.09.2006
Dr. B. Wiebusch

10th Japanese-German Workshop on Water Technology
Berlin, October 9 - 10, 2006

Development of a Technical Controlling and Energy Management
System within the Wupperverband – an Interim Report
Dr.-Ing. Bernd Wiebusch

1 Introduction
In view of the globalization of industry on the one hand and the growing debts of public bodies
on the other hand, public bodies operating water and wastewater systems are increasingly
adopting entrepreneurial management approaches and ways of thinking.
One of the objectives of modern management systems is to provide management with steeringand decision-making tools. By developing a technical and economic controlling system including
appropriate reports, it is possible to counteract the growing pressure on costs.
A further step is to consider significant operating cost items such as energy, consumables(precipitants and flocculants), repair and maintenance separately and to develop dedicatedmanagement systems for these items with a view to reducing expenditure. As regards energy,
the objective of cost reduction is combined with the ecological objective of cutting emissions of
the greenhouse gas carbon dioxide.
All system operators participate in this general development process in accordance with theirsize and their specific tasks. On the basis of general strategic goals, the main challenge isalways to develop specific operational tasks and projects adapted to the size of the organization
concerned and the resources available.
This presentation gives an interim report on the development of a technical controlling andenergy management system at the Wupperverband.

2 The Wupperverband as an operator of water and wastewater facilities in thecatchment area of the Wupper
The Wupperverband is one of the water associations of North Rhine-Westphalia, operating as apublic body under a special statute. The association is responsible for the river basin of the
Wupper, with a total area of 814 km². The River Wupper is about 114 km long, drains thenorthern part of the Bergisches Land region and flows into the Rhine near Cologne. Annual
precipitation in the catchment area varies from 700 to 1400 mm and about 900,000 people livein the area.
Within the catchment area, the Wupperverband is primarily responsible for river maintenance,
low water replenishment and flood management. In this connection, it operates nine reservoirs(one drinking water and eight industrial water reservoirs) and is responsible for waste waterdisposal and treatment in part of the catchment area.
The Wupperverband operates 70 stormwater tanks – the last tanks upstream from the waste
water treatment plants, 60 km of sewers, 11 waste water treatment plants and a sewage sludge
incineration plant. The population equivalent connected to these systems is about 1.1 million.
The association has a workforce of 380 and receives contribution revenue totalling some 100
million euros.
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Dr. B. Wiebusch

3 Elements of technical controlling
A technical controlling system determines at regular intervals key figures which are madeavailable to company management for steering purposes.
The prerequisites for the development of a technical controlling system are as follows:xxxx

Initially, a central process data system of adequate performance is needed.
Then, the technical data must be linked with commercial data from the accounting
system.
A reporting system must be established to present key technical and commercial data;andA system for the determination of key operating data must be introduced.

3.1 Modernization of central process data system
In 2004, the Wupperverband launched a project for the renewal of its central process datasystem. The old system is based on MS Access and was developed within the association stepby-step over a period of 16 years. On the one hand, this system features data selection
mechanisms developed in accordance with operating experience. On the other hand, thesystem is entirely overloaded.
The new system is to represent an improvement and to meet the following criteria:
x Complete central process data system for the wastewater sector, allowing thesimultaneous processing of continuous and laboratory data and integrating all data fromprocessing plants, stormwater tanks, sewers, the central laboratory and external sources
x Easy-to-use evaluation tool with graphics modules designed to reach a large number of
employeesx Capabilities for the rapid analysis of operating conditions for operational optimizationx Standard solution available on the marketplace with standard interfaces to external
programs
x Rapid development and production of standard reports to support the reporting systemand technical controlling.
The project, which was divided into three phases, is currently in progress and implementation is
expected to take about one year for each phase (see Table 1). Phase I includes the selection ofa consultant, the description of the actual situation, the definition of requirements in a working
group throughout the association and obtaining budget proposals to give an indication of thetotal cost. Phase II includes the preparation of a tender specification and the official tendering
procedure (in accordance with VOL, the standard conditions of contract for services to beprovided for public bodies in Germany). As of 15 September 2006, this phase had been
completed and the contract had been awarded. Phase III will now include the installation andcommissioning of the system.
One interesting result of the tendering process was that the system required by the
Wupperverband was not available on the market as a complete unit. The systems available
could only meet about 80% of the specified requirements. Potential contractors considered theapproach for laboratory data selection and evaluation adopted in the old system to be highly
innovative. As a result, suppliers were prepared to invest in this aspect or to waive royalties witha view to making their own products more attractive.
The positive result of these developments for the Wupperverband was that the final price wasabout 70% below the price indicated in budget proposals. This clearly indicates that it can pay
to work intensively on the design and tendering of a system of this type. The total cost breaks
down into about 45% for system design and 55% for the system itself.

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Dr. B. Wiebusch

Table 1:

Project milestones for the replacement of the central process data system

Phase Project milestones

Time frame

Project definition and selection of consultat

I3-4/2004

Description of the status quo of the various existing data system,
preparation of the catalogue of requirements / Development of
the product specification with consultant and internal working
group

7/2004 - 6/2005

Presentation of potential bidders and budget proposals

II

5/2005Preparation of detailed tender specifications describing therequirement catalogue

7/2005-4/2006

Call for tenders

5-9/2006

Installation of the adapted standard system

10/2006 - 3/2007

III
Scheduled commissioning

5/2007

Table 1 shows the time schedule for the various phases of the project.
Standard reports

Generalrequirements

Simulators

Configurable
reports

reports

Excel

Web presentation
External- tools

TimeView
Graph presentation
Plant diagrams

Graphic
evaluation

Calculation formulaeDataevaluation

User/rights
administration

Statisticalevaluation

Data manipulation

File export

Compression stages

InterfacesDataadministration

Data backup
strategy

Operating dataacquisition system

Data to external storage

Updating/
configuration

Key wastewater data
Value status

Data
exportAvailability

Plausibility checks

Data
interchange

Depth of archiving
Manual/automatic
Downloading/
uploadingLaboratory data
Properties

Transfer(Precipitation) event

Continuous
data

Messages

Data sources

Resolution
Minimum/maximum/average values

Alarm signals

Fig. 1: Functional requirements for the design of the new central process data system(LeiKon, 2005)

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Dr. B. Wiebusch

Fig. 1 gives an overview of the general functional requirements to be met by the new central
process data system.
3.2 Development of a reporting system
The reporting system for wastewater operations developed since 2003 has a three-stage
structure. Monthly reports in accordance with DWA code of practice M 260 are generated by theprocess control systems of the waste water treatment plants and are used as a management
tool by plant management.
On the basis of these monthly reports, two-page quarterly reports are produced for eachtreatment plant, using Excel. These reports cover the following items:x

Master data of treatment plantxDigestion performancex

Human resources data (working times,
absences, overtime worked)x

Key sludge treatment datax

Calculated population equivalentsx

Key energy datax

Water flow rates, concentrations,pollution loadsx

Precipitants and flocculantsx

Nutrient conditionsx

Wastewater accepted for treatmentx

Key data of activated sludge processx

Disposal of residual materials and wastexEffluent plots

These quarterly reports contain key technical data but no information on cost. The
Wupperverband is currently working on the expansion of these reports to include cost
information.
Once each year, a more comprehensive status report with about 100 pages is produced. This
covers current and historic development of key technical and financial data. The association
uses this report as a basis for its main wastewater business processes over the following year.
The Wupperverband sees potential for automating the reporting system within the new processdata system, in the definition and annual updating of key technical and economic indicators for
management and budgeting and in linking the technical process data system with thecommercial data system. The Wupperverband already uses a presentation software package
developed by MIK AG on the basis of SAP. In future, technical data from the operating datasystem are to be supplied to this package.
3.3 Participation in national benchmarking projects
As regards the conceptual design of an indicator system for wastewater treatment, theWupperverband has accessed work carried out by 10 major German waste water treatment
plant operators via service contracts. These utilities have established a service company,
aquabench GmbH, which uses and develops a benchmarking process for waste water
treatment plants together with its customers.
The main objective of these projects is to make business processes comparable for allconcerned and to determine and compare key cost figures for each indicator of a sub-process.
The benchmark is always the best value of a subprocess and not necessarily the lowest value(Fig. 2). Within the project, the resulting deviations must be analysed and any measuresrequired must be defined.
The objective of this approach is to supplement the expertise developed within the associationby the know-how available in the sector and to use it for cost optimization.

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Dr. B. Wiebusch

For the second time now, the association is using the existing treatment plant operation moduleand has already carried out benchmarking exercises on five waste water treatment plants. The
measures resulting from the first project, which covered Burg and Hückeswagen waste water
treatment plants, are currently being implemented and no final results of the project areavailable as yet. Other operators report average savings of up to 5% as a result ofbenchmarking.
For corporate benchmarking, the association also uses a method already developed forcomparing key balance sheet indicators of similar companies.
For the projects “analysis and monitoring of indirect discharges" and “reservoirs”, theassociation is participating in the development of methods and will then carry out a comparisonof key figures. In this way, the Wupperverband is actively involved in further development within
the sector.
Fig. 2 shows the system and procedure for benchmarking projects. With annual datacompilation, benchmarking can be used as a controlling tool. For this purpose, it is important tocompile and evaluate the data automatically using an online portal.

Comparison of
key figures(sh ort,(k urz-/mm ed iuitte
m l-un/land glon
frisgtig-te) rm )Deviation

A n a lys iso f ca u s es

N o n -quan tifiab le m ea su res

P o te n tial

(s till to b e inves tig ated o r
still req uiring e xp la natio n)

C a n no t b e chan ge d

Determination of
deviations
from benchmark

Determination of
key figures

Q ua ntifiable/specific m easures

Start offollow-up survey

Controllingbybenchmarking

Implementationof measures

Analysis ofcausesPlan of action

B e s t va lu e A c tu a l va lu eDivision into quantifiable andnon-quantifiable measures

Fig. 2: System and procedure for benchmarking projects

4 Elements of energy management
One of the key challenges faced by manufacturing industry today is to secure energy supplies
at economically acceptable conditions. Attempts by government in 1999 to liberalize the former
quasi-monopoly situation in the energy industry only led to a reduction in energy costs for alimited period of time. Energy prices have now reached a very high level. The reasons are thegeneral global increase in energy consumption on the one hand and the shortage of energy
resources (for example, on the oil market) on the other hand. In Germany, taxes (levies under
the Renewable Energy and CHP Acts, eco-tax and value added tax also account for a relatively
large proportion of the price of energy.
The Wupperverband therefore decided to introduce energy management as a matrix process
covering all the functional units of the association.
The objectives of the energy management process are to reduce energy costs on the one hand
and to minimize carbon dioxide emissions (greenhouse effect) on the other hand.
The operational tasks resulting from the process are as follows:

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29.09.2006
Dr. B. Wiebusch

x
x
x
x
x
x

Transparent tracking and presentation of energy consumption and energy costs within
the Wupperverband,
Brief presentation of energy policy and legal developments,
Further development of energy purchasing methods and contract systems,
Proposal of measures to reduce energy consumption and costs at individual plants,
Proposals concerning the expansion and optimization of power generation fromrenewable energy sources (CHP and hydropower plants),
Development of innovative projects to reduce energy consumption.

4.1 Energy consumption and power generation
The Wupperverband uses 56.8 million kWh of energy per year. Of this figure, 40.4 million kWh
are purchased from external sources. This energy includes electric power, fuel oil, natural gas
and district heat. Table 2 below shows the percentage breakdown of energy consumption by thevarious sources of energy.
Table 2:

Energy used by the Wupperverband

EnergyConsumption WV per year

kWh / aPower (external)

approx. 25.6 Mio. kWh/a

25,600,188

45%Power (internal)

approx. 16.3 Mio. kWh/a

16,348,818

29%

Fuel oilapprox. 1.22 Mio. l/a

12,792,497

23%

Natural gas andpropaneapprox. 132,000 m3/a

1,200,000

2%

District heatapprox. 820,000 kWh/a

820,000

1%

56,761,503

100%

Share

Energy expenses account for approx. 10% of the cost of materials used and approx. 50% of thecost of raw materials and consumables.
Since 2000, energy expenses have risen by an average of about 5 % per year. Among otherthings, this is a result of the expansion of waste water treatment plants to provide more effective
treatment. In addition, the cost of electric power in 2007 will increase by about 25 % comparedwith 2005 if consumption remains constant.
The Wupperverband uses approx. 16.3 million kWh of power generated by the association itself
using packaged CHP plants, hydropower plants and one steam turbine. In addition, theassociation’s hydropower plants generate about 8.7 million kWh of power which is fed directly tothe public grid. The association therefore generates power corresponding to about 60 % of its
own requirements from renewable sources! In addition, the above table shows that electric
power accounts for two-thirds of the energy used by the association.
4.2 Development of an energy data management (EDM) system
The purpose of an energy data management system is to record the energy consumption dataof individual plants and power generated by the association itself almost on a real-time basis.
Initially, the project launched in July 2005 records power purchased from external sources for
17 power use points with special contracts in a central database as a load plot on the basis of
15-minute values. The data is presented using visualization software.

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29.09.2006
Dr. B. Wiebusch

In the next stage of the project, there are plans to record the power generated by CHP andhydropower plants as well as power purchased under general tariffs. It is also planned to export
the data to the future operating data system.
Using the EDM system, it is possible to create updated reports on energy consumption, loadand power generated by the association’s own plants. Where necessary, periods with highenergy consumption (e.g. load peaks) will require more intensive analysis.
Fig. 3 shows the structure of the energy data management (EDM) system.

Variouspower users

Ethernet

WAN

TCP/IP

TCP/IPODBC interface

Various
workplaces

FTP server
Buchenhofen STP
Headquarters

Field office

Sewage treatment
plant
Klärwerk
Calibrated power
meter with effective
power, reactive
power and 15-min.
pulse signals

Export
of
.csv
files

Web application via
intranet

TCP/IP

Data logger withinstallation housing

Ethernet and 230 V
cable: withconnection to
distribution
assembly

Operating datasystem server
Headquarters

Fig. 3: Structure of an energy data management system for the Wupperverband

Reactive power
0.1%

Demand charge
13.7%
Eco-tax
20.8%

Renewable
Energy Act levy
5.1%

Commodity
charge45.1%

CHP levy
0.7%
Meter rental
0.6%
Value added tax
13.8%

Fig. 4: Breakdown of electric power costs into energy components, taxes and levies

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29.09.2006
Dr. B. Wiebusch

4.3 Purchasing of electric power
In 2004 and 2006, the Wupperverband issued calls for tenders for the supply of electric powerin accordance with VOL. The contract was concluded on the basis of supply to the point of use.
In other words, the power supplier concludes a contract with the network operator concerned
and invoices the demand and commodity charges as well as network utilization fees. The term
selected for the contract in both cases was two years.
The tendering process has brought definite benefits. Firstly, all 17 points of use with special
contract now have a simple, standardized power supply contract. Secondly, the increase inelectric power expenses was not as severe as expected, as a result of competition between
suppliers. The association had to accept a 15% increase in electric power cost as of 1 January2005 and a 25% increase as of 1 January 2007.
The price structure of these contracts indicates that the demand and commodity charges
account for 59% and taxes and levies (Renewable Energy Act and CHP levies, electric power
and value added taxes) for 41% of the price of electric power (see Fig. 4).
The association is now in the process of launching investigations concerning the applicability of
new purchasing methods (“timetable purchasing”) in cooperation with a power supplier. This
involves the use of a forecast load curve to be covered by the power purchased. Any excess
quantities purchased or deficits are balanced by the power supplier within a separate balancing
account.
The unbundling of power suppliers has led to the establishment of separate companies for
power sales and network operation. If this structure were reflected by power supply contracts, itwould be necessary to conclude separate network connection and network utilization contracts.
Contracts with network operators would cover the monopoly market of network utilization, while
only the supply of electric power would be included in calls for tenders. This approach could
have an advantage, in that more tenders would be received, especially from energy traders. As
a disadvantage, there would be a slight increase in administration expenses.
The configuration of power supply contracts can have a significant effect on external power
costs.
Average price in ct/kWh (Medium Voltage 10 kV)
Price level: July 2004

Regression analysis of 427 power use points

Duration of use [ h ]xWupper Water Association

Fig. 5: Average price as a function of duration of use of supply points, for delivery and meteringin the medium-voltage range (Specht, 2004)

Fig. 5 shows the relationship between the price of electric power and duration of use [h]. For
this purpose “duration of use” is defined as the power consumption in [kWh] divided by theannual peak load [kW]. If electric power is taken at absolutely the same load figure over theentire year, the “duration of use” is 8,760 hours, corresponding to the number of hours in theyear.
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29.09.2006
Dr. B. Wiebusch

Waste water treatment plants with relatively even power consumption normally have a highduration of use in excess of 5,000 hours, while the duration of use of pumping stations is often
below 1,000 hours. As the hours of use increase, the average price of electric power falls.
Power suppliers reward relatively constant consumption as the peak load capacity to be madeavailable is reduced and the load on power supply systems is more evenly distributed.
Load peaks have a greater detrimental impact on energy expenses with an annual demandcharge than if a monthly demand charge has been agreed,
Another point to be considered is the feeding of power generated by the association fromrenewable sources to the public grid under EEG – the Renewable Energy Act. Consideration of
the energy situation at Buchenhofen waste water treatment plant indicates a revenue potentialof about € 100,000 per year. Since the end of May 2006, the compact CHP plants at
Buchenhofen have been feeding power “virtually” to the public grid. However, it will benecessary to carry out a new viability analysis as a result of the severe increase in power prices
from 1 January 2007.
Under the Oil Tax Act (MinöStG), Section 25 (exemption, reimbursement or tax credits in the tax
area), there is a possibility of tax reimbursements if plants for the combined generation of heatand power have an annual degree of utilization of at least 70%.
This possibility of reimbursement has been used at the sewage sludge incineration plant forsome time.
4.4 Optimization of energy consumption
Standardized energy analyses in accordance with the energy manual for North RhineWestphalia published by the State Ministry of Environmental Protection, Nature Conservation,
Agriculture and Consumer Protection are a key tool for optimizing energy consumption. The
state subsidized these analyses for many years and the Wupperverband has already analysed
six waste water treatment plants. Although the subsidy program has been suspended, thecontinuation of these analyses is regarded as beneficial.
As a result of these analyses, measures are proposed and a general viability assessment ismade. For a more detailed assessment and implementation if appropriate, the proposals areforwarded to the operating departments concerned.
Table 3:

Savings potential as a result of energy analyses and realization

Total(without wwtp Odenthal)
Population equivalent: 191,376
Savings potential determined

Energy(power and heat)

Share inenergy[kWh/a][%]Costdifferential (AB
- AC)
[€/a]

Share incost[%]

2,492,692

100%

96,352100%

1,368,767

55%

85,313

89%

Realization with expansion /modifcation

983,727

39%

-499

-1%

Realization not feasible

31,565

1%

1,217

1%

Other items (clarification required)

108,633

4%

10,323

11%

Of which:
Already realized

Abbreviations: AB = Annual Benefit, AC = Annual Cost, wwtp = waste water treatment plant

Table 3 shows that 55% of the savings potential indicated by energy analyses conducted since1999 in terms of energy savings and 89% in terms of cost savings have already been realized.
D:\Kontakte\Japan\Vorträge\D-Wiebusch.doc- 81 -

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29.09.2006
Dr. B. Wiebusch

39% of the energy savings potential indicated will be realized in the long term in connection withmodifications and expansions.
The connection between power supply contract, peak loads, duration of use and power cost or
average power cost was already mentioned above.
The targeted shut-down or turning-down of individual units as part of a load management
strategy may help in reducing peak loads and the resulting demand charges (see Figure 6).
Where this is economically viable, an automated load management system is normally used.
450
400
350

P [kW]

300
250
200
150
100
50
0
1.1.

31.1.

1.3.

31.3.

Fig. 4: Sample load curve for a waste water treatment plant (for a population equivalent of
50,000) showing load peaks
The Wupperverband is currently conducting studies to determine whether it will be economically
viable to introduce automated load management systems at individual plants. Initial results
show that such systems would have a cost:benefit ratio approaching 1 as a result of the monthly
demand charge provisions. If load management at the plants is not automated, it will benecessary to manage loads manually using the energy data management system. This will only
be possible in connection with a retrospective analysis of the data collected. The experienceobtained could then be considered when selecting future modes of operation.
Table 4:

Overview of studies concerning the feasibility of automated load management
systems for the Wupperverband
wwtp

Annual hours ofuseFeasibility
Study

Base year

2003

Buchenhofen

5,702

5,131

Amortisationin 7.5 years

Hückeswagen

3,699

3,660

C/B = 0.8

Radevormwald

4,083

2,665

C/B = 0.9

Schwelm

2,699

2,415

C/B = 1.1

Burg

4,319

3,340

In progress

2005

Installation

2003
Feeding into network inaccordance withRenewable Energy Act
Together with themodifiation of the wwtp
After expansion of
wwtp
No installation

Abbreviations: C = Cost, B = Benefit, wwtp = waste water treatment plant

In addition, benchmarking projects include a technical and economic assessment of the energy
situation. However, the technical assessment is very rough and is no substitute for an energy
D:\Kontakte\Japan\Vorträge\D-Wiebusch.doc- 82 -

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29.09.2006
Dr. B. Wiebusch

analysis. An important addition by the benchmarking method is the economic assessment
based on the determination of specific consumption costs and, in the case of packaged CHP
plant operation, specific production costs.
4.5 Increasing the share of renewable energy
In order to ensure greater independence from the rising cost of energy purchased from externalsources, it is necessary to increase the share of energy generated by the Wupperverband itself
from renewable sources. In this connection, the Wupperverband can tap potential in thefollowing areas:x Construction and operation of further hydroelectric power plants on the reservoirs
operated by the Wupperverband
x Increase in digestion gas production for power generation by the cofermentation oforganic materials, using vacant capacities in digesters
x Installation of solar power facilities on the association’s buildings
In future, depending on network transmission charges and electric power prices, it may become
viable for the Wupperverband to transmit hydropower to its own waste water treatment plants
for use at those plants instead of feeding it to the public power grid.

5 Conclusion and outlook
The basic structures of a technical controlling and energy management system have beendeveloped within the Wupperverband since 2003. The current technical controlling tasks at
Wupperverband are operating data processing, reporting of key technical and economic dataand participation in external benchmarking projects.
Technical controlling activities in future will include the definition of key technical and economic
indicators and integration in reporting for the management of operating processes and forbudget planning.
Energy management, which will be a matrix process at Wupperverband in future, will have theenvironmental objective of reducing carbon dioxide emissions and the economic objective of
cutting costs. The methods used for achieving these objectives will be the development of apurchasing and contract system adapted to energy markets, the central recording of all energy
data on a real-time basis as part of the reporting system, the use of load management system
to ensure even load factors and energy analyses to optimize energy consumption.
Although the Wupperverband already covers 60% of its energy requirements from renewablesources, there is still potential for increasing this share. In general terms, the power generated
by hydropower facilities could be increased and greater use could be made of organic materials
for cofermentation in the association’s fermentation basins. A review of this potential is currently
in progress.

6 Acknowledgements
The author wishes to thank his colleagues at the Emschergenossenschaft/Lippeverband andRuhrverband for the constructive exchange of ideas and the impetus which they have given to
his work.

7 Sources
Specht, 2004:
Support for the purchasing of electric power (call for tenders in accordance with VOL) by
Ingenieurbüro für Energiewirtschaft und –technik Dr. Specht, Müden

D:\Kontakte\Japan\Vorträge\D-Wiebusch.doc- 83 -

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29.09.2006
Dr. B. Wiebusch

LeiKon, 2005:
Specification for the project “Betriebliche Informationsverarbeitung T1/T2“ (operating dataprocessing, parts 1/2) of Wupperverband, July 2005, Ingenieurbüro LeiKon, Herzogenrath
WIW, 2004
Report on load management for the wwtp Hückeswagen of the Wupperverband,
Wupperverbandsgesellschaft für Integrale Wasserwirtschaft (WIW), Wuppertal

D:\Kontakte\Japan\Vorträge\D-Wiebusch.doc- 84 -

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- 85 -

www.WUPPERVERBAND.de

Catchment Area 814 km²
Wupper Length 114 km,
all rivers in total ca. 2300 km
Precipitation up to 1400 mm yearly,
Population: ca. 1 Mio. people

The Wupper Water Association

www.WUPPERVERBAND.de

Dr. Bernd Wiebusch

Development of aTechnical Controlling and Energy Management
System within the Wupperverband- an Interim Report -10th Japanese-German Workshop on Water Technology
Berlin, October 9- 10, 2006

CologneWupper Catchment Area

The Wupperverband /Wupper Water Association

www.WUPPERVERBAND.de

11 waste water treatment plants
in total 1,1 Mio. population equivalents

The Wupper Water Association

www.WUPPERVERBAND.deRhein – Catchment Area

- 86 -

www.WUPPERVERBAND.decatchment area data Collection and evaluation of river andwww.WUPPERVERBAND.de• Energy consumption and power production• Energy Data Management• Centralised purchase of energy (power)• Optimisation of the energy consumption• Management of power load peaks

 River maintenance Regulation of the river flow

Energy Management (since 2005)• Central Process Data System• Reporting System• Benchmarking

Technical Controlling (since 2003)

Issueswww.WUPPERVERBAND.de

11 waste water treatment plants,
in total 1,1 Mio. population equivalents,
70 storm water tanks,
60 km large sewer pipes for waste
water transportation

The Wupper Water Association

 Waste water collection and treatment

water supply

 Collection and storage of water for the drinking

Responsibilities

www.WUPPERVERBAND.de

11 waste water treatment plants,
in total 1,1 Mio. population equivalents,
70 storm water tanks

The Wupper Water Association

- 87 -

Costs approx. 275 T€

Run-time of the project: 3 years

Scheduled commissioning

Installation of the adapted standard system

Call for tenders

Preparation of detailed tender specifications describing therequirement catalogue

Presentation of potential bidders and budget proposals

www.WUPPERVERBAND.de

III

II

I

Description of the status quo of the various existing data system,
preparation of the catalogue of requirements / Development of
the product specification with consultant and internal working
group

Project definition and selection of consultat

Phase Project milestones

5/2007

10/2006 - 3/2007

5-9/2006

7/2005-4/2006

5/20057/2004 - 6/2005

3-4/2004

Time frame

Central Process Data System [CPDS] - (2)www.WUPPERVERBAND.de

Technical Controlling within the
Wupperverband

Graphic
evaluation

reports

Alarm signals(Precipitation) event

Downloading/
uploading

Availability

Continuous
data

Laboratory data

Dez 05
1.152
38
0,0
3,3

Okt 0534.05927.57443.532

Okt 05
123
24,3
0,036
0,21
0,58

Okt 053,51,8

Nov 05
123
20,6
0,025
0,42
0,80

Nov 052,82,2

Nov 05554.273
265
97
4,0
26,0
3.958
1.518
64
400

Nov 0532.98425.29336.407Dez 05
133
18,4
0,04
0,04
0,55

Dez 054,2
1,6

Dez 05875.407
166
35
2,5
16,0
5.434
1.350
83
554

Dez 0545.28022.50050.392

4
3,5
3
2,5
2
1,5
1
0,5
0

01.10.05

70
60
50
40
30
20
10
0

21.10.05

21.10.05

30.11.05
CSB Bescheid

10.11.05

10.11.05

30.11.05

Hückeswagen 4.Quartal Pges

mg/l CSB hom_

Hückeswagen 4.Quartal CSB

20.12.05

CSB erklärt

20.12.05

Ablauf Klärwerk (Ablaufganglinien der Überwachungswerte CSB, Pges, NH4-N, Nanorg)

ISV
tTS
BTS
ß- Wert Biologie
ß- Wert Flockungsfiltration

3.4 Kennwerte Belebung[ml/g][d][kgBSB5/(kgTS*d)][mol Me/ mol P][mol Me/ mol P]

3.3 Nährstoffverhältnis Zulauf Belebung
CSB / BSB5
BSB5 / Nges

Nov 05
1.382
32
3,8
2,2

[d]

Okt 05

www.WUPPERVERBAND.de

mg/l Pges_

24h- MP; 2h- MP; qualif. Stichprobe

01.10.05

Pges Bescheid

ISV

Nov 05ISV

Nov 05

Nov 05[EW][E]

21.10.05

mg/l NH4-N[mg/l][mg/l][mg/l][mg/l][mg/l][mg/l][µg/l][µg/l][µg/l][µg/l][µg/l][µg/l][µg/l]

30.11.05

Dez 05

Nanorg erklärt

20.12.05

1
5
50
50
50
100
100
** einzuhalten 1.5. - 31.10.

0

2

4

6

8

mg/l NH4-N
10§ 6 AbwAG § 4(5)
AbwAG
60
60
15
18
18
7
0,5
0,5

Bescheid

NH4-N Bescheid

Nanorg Bescheid

10.11.05

Dez 05Dez 05BTS[kg BSB5/ (kg TS*d)]
0,048
0,044
0,040
0,036
0,032
0,028
0,024
0,020
0,016
0,012
0,008
0,004
0,000

48.00033.864

ß-Wert Filter

Hückeswagen 4.Quartal Nanorg und NH4-N

Okt 05

NanorgtTS

Ausbaugrösse
Einwohner

ß-Wert Biologie

Okt 05CSB
BSB5Nanorg **NH4-N *Pges
oPO4-P
Hg
Cd
Cr
Ni
Pb
Cu
AOX
* einzuhalten bei > 7°C

01.10.05

0

5

10

15

mg/l Nanorg
20

200
150
100
50
0

[ml/g]

0,0

0,2

0,4

0,6

0,8

1,0

[mol Me/ mol P]

50,0
45,0
40,0
35,0
30,0
25,0
20,0
15,0
10,0
5,0
0,0

Tel.: 02192 / 1630
Fax: 02192 / 931347
Mail: gro @wupperverband.de* bezogen auf Summe aus geleistete Std + Krankheits-Std

3.2 Wassermengen / Zulaufkonzentrationen / Zulauffrachten
Okt 05
Wassermenge[m³/Monat]
501.623
CSB (24h- MP)[mg/ l]240
BSB5 (24h- MP)[mg/ l]99
Pges (24h- MP)[mg/ l]4,0Nges (24h- MP)[mg/ l]26,0CSB [Fracht][kg/ d]4.087
BSB5 [Fracht][kg/ d]1.654
Pges [Fracht][kg/ d]67
Nges [Fracht][kg/ d]479

3.1 Anschlusswerte berechnet
ccc
EW (CSB) Monatsmittel[EW]
EW (BSB5) Monatsmittel[EW]
EW (N) Monatsmittel[EW]
EW (CSB) 85 Quantil[EW]
EW (BSB5) 85 Quantil[EW]
EW (N) 85 Quantil[EW]

3 Verfahren

Gesamtstunden[Std/ Monat]Überstunden[Std/ Monat]
spezifische Krankenstunden [%]spezifische Überstunden*[%]

Okt 05
1.068
45
12,2
3,7

1 Name und Anschrift des Klärwerkes
Gruppenklärwerk Hückeswagen
Corneliusweg 442499 Hückeswagen

Stunden, Ausfälle, Überzeiten

2 Personal(approx. 100 pages / MS Word)
Current and historic development of key technical and financial data

• Yearly Status Report

Minimum/maximum/average values

Resolution

Properties

Automation in the CPDS

Data sources

Datainterchange

Updating/
configuration(2 pages / MS Excel)- Master data of wwtp,- HR data (working times, absences, overtime)- Calculated population equivalents- Water flow rates, concentrations, pollution loads- Nutrient relations,- Key data of activated sludge process- Effluent plots- Treatment efficiency- Key sludge treatment data
- Key energy data
- Precipitants and flocculants- Wastewater accepted for treatment- Disposal of residual materials and waste• Monthly Reports• Quarterly Reports

Reporting System

Messages

Transfer

Plausibility checks
Manual/automatic

www.WUPPERVERBAND.de

Depth of archiving

Value status

Key wastewater data

Data to external storage

Data
exportInterfaces

Data backup
strategy

Operating dataacquisition system

Excel
TimeView

File export

Statisticalevaluation

Calculation formulae

External- tools

Simulators

Compression stages

Dataevaluation

Web presentation

Data manipulationDataadministration

Plant diagrams

Graph presentation

Configurable
reports

Standard reports

User/rights
administration

Generalrequirements

Modernisation of the central process data collection and evaluation in
the waste water treatment department

Central Process Data System [CPDS] - (1)- 88 -

Gesamtaufwand je angeschlossenen EW CSB120 (85%-Wert)[€/EW CSB120 (85%-Wert)]

A n alysis
o f c au ses

KA 30310.000

KA 306EW CSB 120 (85%-Wert)

KA 304100.000

KA 305

KA 310

KA 307
KA 302

KA 308KA 301

Costs / PECSB120,85% <> Size of the Plant

www.WUPPERVERBAND.de

0,00
1.000

2,00

4,00

6,00

8,00

10,00

12,00

14,00

16,00

18,00

20,00

C a n n o t b e cha n ge d(s till to be inves tigated o r
still req uiring e xpla natio n)

N o n -q ua n tifiab le m ea s u re s

KA 311

Gesamtaufwand TP mechanische Reinigung je angeschlossenen EW CSB120 (85%-Wert)
Erhebungsjahr: 2003

Benchmarking: KPI´s

www.WUPPERVERBAND.de

B e s t va lu e A c tu a l va lu e

Deviation(sh ort,(k urz-/mm edium
ittel-und/langlongfris tig)-te rm )Q ua ntifiable/specific m easures

Comparison of Key Performance Indicators (KPI)

Benchmarking

1.000.000

KA 309P o ten tial

Process part
Sub Prozess

Gas flare

M ittle re Ab w eic h u n g

K o ste n In sta nd h.
(= 551 /5 52 +5 47 1+ 54 72+ 5 43 b
+ 54 9)/ a ng e. E inw . (C S B 85P erc.-W ert)

L öhn e un d G e hä lter (55 ) ink l.
externe D L Instand h. (547 1)/
an ge . E in w . (C S B 8 5-P e rc.W e rt)

K o sten E n erg ie (54 0)/ a ng e.
E inw . (C S B 8 5-P erc.-W e rt)

B e trieb sau fw and / a ng e. E inw .
(C S B 8 5-P e rc.-W e rt)

K en n zah l

www.WUPPERVERBAND.de

4

3

2

1

lfd .
N r.

€ pro E W

€ pro E W

€ pro E W

€ pro E W

E in h eit
K en n zah l< 10 0.0 00 E W C S B 1 20 (8 5% -W e rt)

0 ,87

1 ,02

3 ,13

5 ,23

Ist- W ert

0 ,46

0 ,73

1 ,98

4 ,01

Z ielw ert

U rs a c h e n a n a lys e B io lo g is c h e R e in ig u n g
Group
301
A n la g e :D aten stan d: 1 4 .1 0 .2 0 0 4

Flood water
pumps

Laboratory

Workshops

1,06

1,26

2,16

4,40

Ø -W ert

0,41

0,29

1,15

1,22

Ab w . zu m
Z ielw ert
ab s.

54,3%

8 9,1 %

3 9,7 %

5 8,1 %

3 0,4 %

g g f. Ab w .
zu m
Z ielw ert in%

letzte T e xtä nd erun g: 1 4 .1 0 .2 0 0 4

All

Benchmarking: Cause Analysis

www.WUPPERVERBAND.de

AssociatedZugehörige
buildings
GebäudeWith P-removal

AssociatedZugehörige
building
GebäudeCover
Abdeckung
Odour Treatment*

Waste water
pumps

Digestion gas
storage

Surplus sludge
pumps

Precipitation

Storage
Lager
Water Supply

Sludgestabilisation

Return Sludge
pumps
pumpwerk

Disposal of sandand screenings
AssociatedZugehörige
Buildings
GebäudeAssociatedZugehörige
Buildings
GebäudeOther buildings

Odour
Treatment

Reuse / Disposal/ Dumping

TrocknungDryingMembrane
Reactor-

Odour
AbluftTreatment
behandlung

behälterSludge storage

After thickening

AssociatedZugehörige
Buildings
GebäudeFinal clarifyer

Prim. sludge pumps
pumpwerk

Installations
pipes

Infrastructure

OthersIntermediate
Clarifyer

Entwässerung
Dewatering

Transport
Transport zur
Entsorgung

SludgedisposalPrimary
Tank
Vorklärung

Faulbehälter
Digester

PreVoreindicker
thickening

Sludgestabilisation

Puffer lake

Filtration

Advanced
Treatment

6,7%-17,9%-19,0%

44,9%

18,9%

g g f. Ab w .
zu m
M ittelw ert
in %Others

Grit Sandfang
chamber

Biological
Biologischer
Reactor*Reaktor*1

BiologicalTreatment

Sludge Path

Aeration
SystemScreens

MechanicalTreatment

Water Path

Process Modell

- 89 -

Schlammstabilisi Nutzung des zweiten Faulbehälters
erung(Testprojekt! Siehe Energieanalyse)

17

X

X

X

X
X

www.WUPPERVERBAND.de

Implementationof measures

Start offollow-up survey

Controllingbybenchmarking

Plan of action

Analysis ofcausesDetermination of
deviations
from benchmark

Zuständiger Betriebsingenieur muß ein
Zeitkontingent für dieses Projekt
Reduzierung der Stromkosten
haben.
Zuständiger Betriebsingenieur muß ein
Zeitkontingent für dieses Projekt
Reduzierung der Stromkosten
haben.
Gasmessung muß überprüft und ggf.
in Ordnung gebracht sein. Zuständiger
Reduzierung der Energiekosten /Betriebsingenieur muß ein
Gewinnung von Wärme
Zeitkontingent für dieses Projekt
haben.

Division into quantifiable andnon-quantifiable measures

Determination of
key figures

Comparison of
key figures

Nutzung der Rührwerke als
Ersatzaggregate, d.h. Reduzierung
von Instandhaltungsaufwand

W a s s o ll m it d ie s e r M a ß n a h m e
b e w irkt w e rd e n ?

Z ie ls e tzu n g

Probeweise Installation eines FU´s zur
stufenweisen Herunterregelung bei
gleichzeitiger Erfassung desReduzierung der Stromkosten
Mischergebnisses Keine Nachrüstung
von FU´s. Sondern Betrieb von nur 1
Rührwerk und zwar wechselnd.

keine

erw arte teerw artete
W e lch e B e d in g u n g e n m ü sse n e rfü llt se in ,E insparun g läss t E insp aru ng läs stu m d ie s e M a ß n a h m e n u m s e tze n zu
sic h konk re t insich nicht
können?
E U R benen nenb eziffern

V o ra u s s e tzu n g e n

Target: The Benchmarking - Loop

www.WUPPERVERBAND.de

540

Absenkung des Schlammalters in der biol. Stufe(s. Energieanalyse)

biol. Reinigung

16

540

540

Optimierung des Rückführverhältnisses (s.
Energieanalyse)

biol. Reinigung

15

0

540

Überprüfung des Rührwerkbetriebes in den
Denitrifikationszonen

biol. Reinigung

14

18

5472

Stillegung / Ausbau von 10 (?) Rührwerken(siehe Energieanalyse)(N r. aus
(B en ennung d er M aß nahm e die a ngedac ht ist.
E rhe bungsD iese S p alte w ird autom atisc h aus de n F o lges eiten ge fü llt) bo gen kfm .
K e nngröß en)q u a n tifizie rb a r
k fm . K e n n (B itte zu tre ffe n d e sg rö ß e n
a n k re u ze n )jan e inbiol. Reinigung(M ec h., B io. etc.)

R e in ig u n g s M aßnahm es tu fe13

N r.

Benchmarking: Plan of Actions
WWTP VII -> 2 wwtp with 170 TPE(Project type: moderated)aquabench GmbH

Yearly data collection in the framework of theOnline-Benchmarking System

www.WUPPERVERBAND.de

The Energy Management System
within the Wupperverband

www.WUPPERVERBAND.de• Target:indicators)• 2005/06: Company benchmarking (balance sheet

Pilot project: Central and de-central waste
water laboratory• 2005/06: Water reservoirs -> Pilot project: 2 WR
• 2005/06: Analysis and Monitoring of Indirect Discharger(Project type: Moderated with OnlineDatabase)• 2005/06: WWTP VIII -> 3 wwtp with 87 TPE• Partner:• 2004:

Benchmarking: Time Schedule- 90 -

approx. 16.3 Mio. kWh/aapprox. 1.22 Mio. l/aPower (external)

Power (internal)

Fuel oilapprox. 820,000 kWh/aDistrict heat

Biogas Power75%

Steam Power11%

kWh / a1%
100%

820,000

www.WUPPERVERBAND.de

Operating datasystem server
Headquarters

www.WUPPERVERBAND.de

Ethernet and 230 V
cable: withconnection to
distribution
assembly

Ethernet and 230 V
cable: withconnection to
distribution
assembly

Calibrated power
meter with effective
power, reactive
power and 15-min.
pulse signals

Sewage treatment
plant
Klärwerk

TCP/IP

Operating datasystem server
Headquarters

Export
of
.csv
files

FTP server
Buchenhofen STP

TCP/IP

Data logger withinstallation housing

TCP/IP

Field office

Web application via
intranet

Headquarters

Variouspower users

Ethernet

Various

Field office

Web application via
intranet

Headquarters

workplaces
TCP/IPODBC interface

WAN

Steam power (internal generation)

www.WUPPERVERBAND.de

Hydro power (internal generation)

Biogas power (internal generation)

25.600.188 kWh;62%

Electric power (external sources)

2.258.310 kWh;5%

12.254.832 kWh;29%

1.835.676 kWh;4%

Total Power Consumption 2005: 41.949.006 kWh- Purchasing of electric power and power generated by the Wupperverband -Data logger withinstallation housing

Export
of
.csv
files

FTP server
Buchenhofen STP

workplaces
TCP/IPODBC interface

TCP/IP

Various

WAN

Ethernet

Calibrated power
meter with effective
power, reactive
power and 15-min.
pulse signals

Sewage treatment
plant
Klärwerk

Variouspower users

2%

23%

29%

45%

Share

56,761,503

1,200,000

12,792,497

16,348,818

25,600,188

Structure of an energy data management (EDM) system

www.WUPPERVERBAND.de

Hydro Power
14%

Electricity produktion of the Wupperverband

approx. 132,000 m /aNatural gas and propane

3

Consumption WV per year

approx. 25.6 Mio. kWh/a

EnergyEnergy consumption, power production

- 91 -

supplier

13,147 €

36,672 €Services

In total

www.WUPPERVERBAND.de•

Wupper Water Association

Duration of use [ h ]Regression analysis of 427 power use points

Price level: July 2004

Average price in ct/kWh (Medium Voltage 10 kV)

Annual duration of use and average power costwww.WUPPERVERBAND.de

2.821 € / power consumer
18 data logger: approx. 2.241 € / power consumer

8,796 €

14,729 €Total cost(gros)

SoftwareHardware and other materials

Cost type• Optimisation and flexibility of the energy purchasing

billing and the reporting• Automatically evaluation of the power consumption, thewww.WUPPERVERBAND.de

Commodity
charge45.1%

Reactive power
0.1%

Value added tax
13.8%

Demand charge
13.7%

Meter rental
0.6%

CHP levy
0.7%

Renewable
Energy Act levy
5.1%

Eco-tax
20.8%

Elements of the power costs in Germany (2005)

www.WUPPERVERBAND.depurchase in relation to the power load curve.

• Investigation of new procurement methods, like scheduledutilisation• Separated contracts for network access and network

Delivery period: 2007/08 +1 +1
Delivery quantity: 21.5 Mio. kWh
Delivery „All inclusive“
5 charges, 19 offers = 3 – 5 offers per charge• Second call for tenders with 13 power consumers in 2006

Delivery period: 2005/06 +1 + 1
Delivery quantity : 27.7 Mio. kWh
18 power consumers
Delivery „All inclusive“
10 charges, 24 offers = 2 - 3 offers per charge• First Call for tenders for Power purchase in 2004:

Targets of the EDM:

• Quick availability of data in a consistent format,• Transparency of data, independence from the power

Power Procurement

Targets and cost of the Energy Data Management

- 92 -

3,699

4,083

2,699

4,319

Hückeswagen

Radevormwald

Schwelm

Burg

3,340

2,415

2,665

3,660

5,131

In progress

C/B = 1.1

C/B = 0.9

C/B = 0.8

Amortisationin 7.5 years

2003

Installation

11%

1%

-1%

89%

100%

No installation

After expansion of wwtp

Feeding into network inaccordance withRenewable Energy Act
Together with themodifiation of the wwtp

10,323

1,217

-499

85,31396,352[%]

Share incost

www.WUPPERVERBAND.dechallenge• Investigation of more wwtp´s• Implementation and Adaptation is a big operational

Abbreviations: C = Cost, B = Benefit, wwtp = waste water treatment plant

5,702

4%

108,633[€/a]

Cost differential(AB - AC)

Feasibility Study

1%

39%

55%

100%

[%]

Share inenergy31,565

983,727

1,368,767

2,492,692[kWh/a]Annual hours of
use
2003
2005

Buchenhofen

Base year

WWTP

Load Management

www.WUPPERVERBAND.deAbbreviations: AB = Annual Benefit, AC = Annual Cost

Other items (clarification required)

Realization not feasible

Detailed analysis

Detailed analysis

Detailed analysis

Rough Estimation Analysis

Detailed analysis

Detailed analysis

Rough Estimation Analysis

Analysis

Energy(power and heat)

90,01639,00732,500Realization with expansion / modifcation

Already realized

Of which:

Savings potential determined

Population equivalent: 191,376

Total(without wwtp Odenthal)

Burg

Mrz 06

2,143

Dhünn

Odenthal

Nov 01

Hückeswagen

Schwelm

Mrz 01

Feb 02

13,500Marienheide

Nov 04

12,700Wermelskirchen

Apr 99Feb 01

15,010PE

WWTP

Completion

Energy Analysis acc. to the “Manual NRW“

1.3.

31.3.

www.WUPPERVERBAND.de

new task in the business. It is using the online data transfer fromlocal plants and is focusing on the collection and presentation of
the power load curve. It will support the purchasing andconsumption of electric power actively.

• The development of an Energy Data Management System is avarious business processes intensely. The aim of the process
benchmarking of wwtp´s is to generate the key performanceindicators on an online platform once a year
(www.aquabench.de).

• The Wupperverband is using the Benchmarking – Method in

the Wupperverband is developed and is available for the
management. It needs – however – optimisation, especially forthe use of technical and economical Key Performance
Indicators.

• The Reporting System for the waste water treatment plants of

the Wupperverband gets a modern, flexible and user-friendly tool
for process optimisation and technical controlling.

31.1.

Conclusion and outlook (1)• With the installation of the new Central Process Data System

www.WUPPERVERBAND.de

0
1.1.

50

100

150

200

250

300

350

400

450

Load Managment

P [kW]

- 93 -

www.WUPPERVERBAND.de

reduce energy costs. It is difficult to find a balance between
power load reduction and an efficient waste water treatment
process. The Wupperverband is not using automatic load
management systems yet but will – however – install them undinvestigate further waste water treatment systems.

• Automatic Load Management Systems are an effective tool toAnalysis of the Manual NRW is successful and will be
continued.

• The reduction of power consumption by carrying out Energy

in terms of the market conditions - influenced by the European
Energy Exchange (EEX) - difficult and seems not to beeconomical.
It is important to look at new methods which are on the one side
faster and more flexible but have on the other side a limited risk
and fulfil the regulations for purchasing by public companies.

• The Purchase of Electric Power with fixed tender processes is

Conclusion and outlook (2)www.WUPPERVERBAND.de

your attention !

“Domo Arigato” forEconomic Instruments for Basin-wide
Efficient Pollution Load Reduction- Comparison between Effluent Charges
And Water Quality Trading Osamu Fujiki** Research Fellow & Director of 1st Research Department, Japan Institute of Wastewater
Engineering Technology, IKEBUKURO CHITOSE Bld. 7F, 1-22-8,Nishi-Ikebukuro,
Toshima-ku, Tokyo, 171-0021 Japan, Phone: +81-3-5951-1331, E-mail: o-fujiki@jiwet.or.jp
Abstract: Sewerage Law was amended in 2005 and a modified approach was established byintroducing the concept of transferable LRA (Load Reduction Assignment) for nitrogen andphosphorus in the basins of enclosed water bodies. The modified approach is supposed to play arole equivalent to water quality trading which has been adopted successfully in the U.S..
Meanwhile the effluent charge system combined with subsidy is widely employed with great
success in European countries such as Germany. Through simplified mathematical models, thecomparative features on equity and reflection of local conditions as well as equivalency between
the two economic instruments are theoretically discussed. The mathematics for both the effluent
charges and water quality trading suggests an equivalent cost-effectiveness in meeting apredetermined target. Water quality trading could be easily designed on the basis of the total sumof permits that is the predetermined target of the policy, while effluent charge system cannot bedesigned directly from the target. In contrast, effluent charge system is assumed to be superior towater quality trading in terms of equity and the reflection of local conditions.
Keywords: effluent charge, water quality trading, transferable permit, load reduction assignment,
amendment of Sewerage Law

1. Introduction
Economic, engineering and political studies as well as administrative experiences have revealed thattraditional “command-and-control” measures are not enough to address the externality-related issues such as environmental management strategies.
Economic instruments are considered to becost-effective alternatives, which should be applied solely or together with command-and-control
method1),2). As for the economic instruments for water pollution control, typical examples are effluent charge system and water quality trading. The former is very popular in European countries,
among which Germany has made the greatest success of pollution prevention3). The latter has
been applied to quite a few watersheds in the United States, where Environmental Protection
Agency (EPA) issued Water Quality Trading Policy in 2003 to facilitate the attainment of Total
Maximum Daily Load through water quality trading4). Comparative studies were conducted focusing on these two methods from the viewpoint of applicability to sewerage works in Japan. Furthermore there were energetic arguments for and against employing new economic incentives andscientific discussions about the design of the legislation.

2. Difficulties Relating to Advanced Treatment
The water quality has been improved gradually so far in rivers. But most of the enclosed water
bodies such as bays and lakes are not getting cleaner in spite of the progress in the population
served with sewage treatment (See Figure 1). It is no wonder that those enclosed stagnant water
bodies, which are severely polluted by eutrophication, require the reduction in nitrogen or phosphorus inflow through the promotion of advanced treatment of sewerage systems in those basins. In- 95 -

particular, advanced treatments in Tokyo Bay and Osaka Bay basins are considered to be most effective because almost 90% of population is covered by sewerage and more than half of nitrogenand phosphorus inflows into those water areas through effluent from public WWTP(wastewater
treatment plant)s. Therefore, it is no exaggeration to say that the averaged water qualities in Tokyo Bay and Osaka Bay are fundamentally controlled by the water quality of the effluent from public WWTPs. However the rate of population covered with advanced treatment is very low, 3.6% forTokyo Bay and 14.1% for Osaka Bay as of the endof fiscal 2003.

- 96 -

ٌٌ RiverType B (BOD less than 3)

Main sewer

Type A(BOD less than 2)

The requirements of advanced treatment i.e. effluent water quality that each WWTP is to meet areusually determined by CBPSS (Comprehensive Basin-wide Plan of Sewerage Systems). CBPSS was
legislated in the Sewerage Law as early as 1970.
Every prefecture is by law to formulate CBPSSs forordinance-required water bodies to drive local entities concerned to advance their sewerage construction/improvement projects toward the attainment of
EWQS (Environmental Water Quality Standard) inthe targeted water bodies (See Figure 2). Although
Figure 1: Achievement of Environmental
Sewerage construction/improvement programs shallWater Quality Standard
be made and implemented “in accordance with” the Notes :1.BOD used for rivers, and COD used for lakes/reservoirs, andrelevant CBPSS, CBPSS could not function as strictsea/coastal areas.
command-and-control measures and it is often very 2.Achievement level (%)=(no. of water bodies achieving /number of designated water bodies) u 100
difficult to guide local entities toward advanced treat- Source : Ministry of Environment
ment just as is required by CBPSS for the following
reasons;
E Town(1) Sewerage Law postulates that CBPSS should be㨀formulated taking cost-effectiveness into account. Basin- 㧰 village
wide cost-effectiveness is theoretically guaranteed on the㨀condition of the equalization of marginal reduction costs
across all the WWTPs in the basin. However prefectures
Treatment Area
formulating CBPSS cannot determine the marginal
reduction costs beforehand in reality.
C City(2) The expression “in accordance with” does not necessar- B town
ily imply “coinciding with” juridically. Therefore it is
not perceived as illegal for local entities to postpone, for 㧭 city
C City㨀
some reasons, the initiation of advanced treatment which
CBPSS requires. In other words, command-and-control
method cannot be easily applied on the basis of CBPSS.
㨀
wastewater(3) Generally speaking, local entities tend to be unwilling to Treatment Plant 
forward the program of advanced treatment in pursuit of ‫)غغ‬WNH
Type B㧦Environmental water
downstream benefit alone. Meanwhile, there is often no COD d 3mg㧔㧯㧻㧰/ l N dNGUUVJCP㧕
0.3mg / l 㧕
quality standards
sufficientreasonable
persuasivenessotherthan P d 0.01mg / ldownstream
benefit to make local entities carry out Figure 2 : Schematic Diagram
programmed advanced treatment.
of CBPSS
Taking heavily polluted lakes and bays into consideration,some kind of modified approach was obviously needed topromote the advanced treatment in Japan.

3. Modified Approach
Sewerage Law was amended in 2005 and a modified approach was established by introducing theconcept of LRA (Load Reduction Assignment) for nitrogen and phosphorus in the basin of enclosed
water bodies. Transferable LRA is somewhat similar to transferable permit in the water quality
trading employed in the U.S.. While water quality trading is founded upon NPDES (National Pollution Discharge Elimination System), LRA is a concept in CBPSS and therefore only applied tothe advanced treatment of WWTPs.
The outline of the amendment of Sewerage Law is as follows;
A. Determination of the Baseline LRA
Prefecture shall determine the baseline LRA for nitrogen or phosphorus contained in the effluentof relevant WWTPs in the CBPSS which targets on enclosed water bodies where EWQS of nitrogen or phosphorus is set.
B. Cooperation for Advanced Treatment between Local Entities
B-1 Proposal of Substitution
Local entity can submit to the prefecture a proposal that it will substitutively fulfill the LRA assigned to the other entity’s WWTP, after reaching the agreement with the local entity to be substituted for on this issue.
B-2 Registration in CBPSSThe prefecture that has received the proposal of substitution can register the information of thesubstitution including the estimated cost and its sharing in the CBPSS.
B-3 Payment for Substitution
The local entity that substitutively fulfills the LRA assigned for the other entity’s WWTP can, as
the legal effect of the registration in CBPSS, make the entity to be substituted for pay the cost forthe substitution including the cost of construction, improvement, rehabilitation, repair, maintenance and control.
B-4 Subsidy Rate
As to the construction or improvement of the facility which is carried out for the purpose of thesubstitution, the subsidy rate for the WWTP whose LRA is substitutively fulfilled is applied. In
the calculation of subsidy, the cost specified for the other WWTP is basically derived from the ratio of LRA for the other WWTP to all the LRA to be fulfilled by the facility.
Legally there is no concept of the permit for discharging pollutant, much less the concept of transferable permit in Japan. After juristic studies, the concepts of LRA and substitution for another
WWTP’s duty on LRA were introduced to substantially establish the transferable permit for discharging pollutant, i.e. transferable LRA on the basis of CBPSS. In other words, transferable LRA
is supposed to play a role equivalent to transferable permit in water quality trading. Modified approach with transferable LRA is expected to substantially abate aforementioned difficulties to guidelocal entities toward advanced treatment, because local entities, which can take the choice of substituting for the other local entities or being substituted for by the other local entities on LRA, will beable to conform to the CBPSS more easily as a whole.
In course of the studies on economic instruments for advanced treatment, it was pointed out that
effluent charge system has quite a bit advantage over water quality trading. However, the modified approach seems to have been favoured by policy makers mainly because of its plain structurethat could be designed easily on the basis of predetermined target as well as of the general public
resistance to charging/taxation.

- 97 -

4. Theoretical Comparison
This chapter deals with some theoretical considerations in order to make a comparison between effluent charges and water quality trading. Herein, let effluent charge system be combined with subsidy where the collected charges are distributed to WWTPs for their advanced treatment and “effluent charge system” or “effluent charges” is referred to as “effluent charge system combined withsubsidy” in this paper. In water quality trading, transferable permit of each WWTP can be sold toor be bought by the other WWTPs as marketable goods. The modified approach shown in the preceding chapter is similar to water quality trading system, which is referred to also as “transferable
permit system”. Figure 3 is the schematic diagram of theses two types of economic instruments.
Take notice of the relation that the permit seller is correspondent to WWTP which substitutes forthe other WWTP in terms of LRA and that the permit buyer is correspondent to WWTP that aresubstituted for by the other WWTP. Baseline load is the initial permit allocated between WWTPs.
In water quality trading system, only the portion above baseline load is transferable.
Let the targeted water be completely mixed and receive m constituents of pollutant discharged fromn WWTPs, each of which has its own cost and marginal cost functions related to any value of discharged pollution load of m constituents. Both effluent charge system and water quality trading
are supposed to be separately applied to the WWTPs in the watershed with the policy to reduce thetotal sum of pollution loads to predetermined target values. Definitions of the variable symbols
are listed in Appendix Σ.
PermitAuthority

Payment

Effluent Charge

Subsidy

Baseline (Initial Permit)
Reduction
by Advanced
Treatment

Reduction
by Advanced
Treatment

Pollution Load

Pollution Load

Pollution Load

Local Entity

Local Entity A
Permit Seller

Local Entity B
Permit Buyer

Water Quality Trading(Transferable Permit)

Effluent Charge
Combined with Subsidy

Figure 3 : Schematic Diagram of The Two Types of Economic Instruments
4-1 Equivalency between The Two Types of Economic Instruments
In water quality trading, net cost for each WWTP is expressed as follows:myici  ¦ D k ( xi ,k  Li ,k )

(1)

k 1

where (net cost) { (cost for advanced treatment)  (expenditure for acquiring permit)  (revenue
by selling permit).
As each WWTP tries to minimize the net cost for given D k ,
wyi
wci
(2)
 Dk 0wxi ,k wxi ,kThis is the condition of market equilibrium. On this condition, we have:- 98 -

wc j

wci
wxi ,kD k

wx j ,k

for

iz j

  

(3)

That is, marginal cost for advanced treatment of the constituent k is equalized to D k for every
WWTP. Eq. (2) and eq. (3) are necessary conditions and so, if the net cost is minimized for any
WWTP i, then xi ,k and D k should satisfy eq. (2) and eq. (3). In pursuit of simplification, let us
skip the perplexing discussions about the existence of appropriate solutions hereafter.
The total sum of the net cost Y is expressed as:
n

n

m

i 1

i 1 k 1¦ ci  ¦¦ D k ( xi,k  Li ,k )Y   (4)

Taking eq. (3) into account,wciwY    (5) D k D k  D k 0
wxi , k wxi ,kwhich means that Y is minimized.
If the total amount of sold permit is equal to the total amount of bought permit for every pollutant,thenn¦ (x  L ) 0
i ,k

i ,k

 

for any k

(6)

i 1

Consequently,
Y

n

n

m

i 1

i 1 k 1¦ ci  ¦¦ D k ( xi ,k  Li,k )

n

¦c

(7)

i

i 1

This means that total cost of advanced treatment is minimized as well as total sum of net cost.
nSince the condition (6) is not always satisfied and ¦ ( xi ,k  Li ,k ) % 0 for any WWTP in general,i 1n

Y % ¦ ci(8)i 1This means that some permits are usually left unsold and that some kind of system of buying thesurplus permits might be necessary to bridge the gap between demand and supply of permits.
In effluent charge system, net cost for each WWTP is expressed as follows:m(1  g )ci  ¦ E k xi ,k

yi

(9)

k 1

where (net cost) { (cost for advanced treatment)  (subsidy for advanced treatment)  (effluent
charge).
As each WWTP tries to minimize the net cost for given g and E k ,
wyi
wc
(10)
(1  g ) i  E k 0
wxi , kwxi ,k?

wci
wxi ,kwc j
wx j ,k



Ek
1 g

for

iz j

(11)

This means that marginal cost for advanced treatment of the pollutant k is equalized to

Ek
1 g

for

every WWTP.
If D k is uniquely determined through marketable permit transfers for given cost function of advanced
treatment, then correspondent relation between eq. (3) and eq. (11) gives the conclusion that xi ,k- 99 -

in effluent charge system and xi ,k in water quality trading system could be equalized to each otherby adjusting parameters D k , E k and g as follows:

Ek

Dk

1 g
The total sum of the net cost Y is expressed as follows;
n

n

m

i 1

i 1 k 1

(1  g )¦ ci  ¦¦ E k xi ,k

Y

(12)

(13)

Taking eq. (11) into account,
wc
wY
(14)
(1  g ) i  E k  E k  E k 0
wxi ,kwxi ,kwhich means that Y is minimized.
Since the source of subsidies is the collected effluent charges, total sum of subsidies could be equal
to total collected charges as:nng ¦ cim¦¦ E x(15)

k i ,ki 1

i 1 k 1

n

n

m

i 1

i 1 k 1n

(1  g )¦ ci  ¦¦ E k xi ,k

? Y

¦c

i

(16)

i 1

This means that total cost of advanced treatment is minimized as well as total sum of net cost.
From eq. (12) and eq. (15), we have:nD k ¦ ci

Ek

DkC

i 1
n m

n

¦ c  ¦¦ D xi

k i ,ki 1

i 1 k 1nm

k i ,kgnmi

k i ,ki 1 k 1

k 1

¦D X
k

k

k 1

¦ c  ¦¦ D x
i 1

C  ¦Dk X km¦¦ D xi 1 k 1
n

(17)

m

(18)

m

C  ¦Dk X k
k 1

When the market equilibrium conditions xi ,k , ci and D k are known for any i and k in the water
quality trading, then the effluent charge system which has the same results of xi ,k and ci as thewater quality trading could be obtained by eq. (17) and eq. (18).
Although the mathematics for both the effluent charge system and water quality trading suggests anequivalent cost-effectiveness in meeting a predetermined target, their practical difference is how theuniform charge rate or transferable permit price is determined. As is clear from the discussions
above, water quality trading system could be easily designed on the basis of the total sum of permits
which is the predetermined target of the policy, while effluent charge system cannot be designed
directly from the target.
4-2 Equality of Unit Net Cost
Discussions of economic instruments for water pollution control sometimes focus on equity as wellas on cost-effectiveness. Equality of unit net cost is assumed to be an indicator of the equity between WWTPs and the equality can be quantitatively evaluated by the standard deviation of unit net
costs for advanced treatment. Smaller value of the standard deviation might well be perceived asstronger equity.
Putting eq. (17) and eq. (18) into eq. (9), we have:- 100 -

CyimC  ¦Dk X k

m

m

k 1

k 1

(ci  ¦ D k xi ,k ) (1  g )(ci  ¦ D k xi ,k )

(19)

k 1

Therefore, unit net cost yi qi in effluent charge system is expressed as follows;mEffluent charge system : yi qi
Next, let baseline load Li ,kLi ,k(1  g )ci  ¦ D k xi ,kk 1

qi
be expressed as follows:

(20)

(21)

qi rk

which means that rk the baseline concentration of the constituent k is constant among WWTPs.
This condition seems reasonable from the viewpoint of equity.
Then, from eq. (1) in water quality trading,mci  ¦ D k xi ,kWater quality trading : yi qi

k 1m ¦ D k rk

(22)
qi
k 1
Comparing eq. (20) with eq. (22), we have:
V C (1  g )V T % V T(23)This means that effluent charge system is reasonably estimated to be superior to water quality trading in terms of equity.
㪌㪇㪙㪸㫊㪼㫃㫀㫅㪼㩷㪧㪼㫉㫄㫀㫋㪮㪸㫋㪼㫉㩷㪨㫌㪸㫃㫀㫋㫐㩷㪫㫉㪸㪻㫀㫅㪾㪜㪽㪽㫃㫌㪼㫅㫋㩷㪚㪿㪸㫉㪾㪼㪬㫅㫀㫋㩷㪥㪼㫋㩷㪚㫆㫊㫋㩷㩿㫐㪼㫅㪆㫄㪊㪀

㪋㪇
㪊㪇
㪉㪇
㪈㪇
㪇
㪄㪈㪇
㪇

 

㪉㪇㪇㪃㪇㪇㪇

㪋㪇㪇㪃㪇㪇㪇
㪍㪇㪇㪃㪇㪇㪇
㪜㪽㪽㫃㫌㪼㫅㫋㩷㪝㫃㫆㫎㩷㪩㪸㫋㪼䇭㩿㫄㪊㪆㪻㪸㫐㪀㪏㪇㪇㪃㪇㪇㪇

㪈㪃㪇㪇㪇㪃㪇㪇㪇

Figure 4 : Relation between Unit Net Cost And Effluent Flow Rate
to Evaluate The Equality of Unit Net Cost

Figure 4 shows the Difference in equality between Baseline Permit, Water Quality Trading and Effluent Charge System, which is estimated by a case study of the simulation for Tokyo Bay basin- 101 -

(See Appendix Τ ).

Here, we have V C

2.3
㧔yen/m3 ) , V T =4.7(yen/m3 ) , g=0.57 , and soeq.(23) is approximately valid as V C =2.3 | (1-0.57) u 4.7=2.021 .

4-3 Reflection of Local Conditions
Discussions have been held so far on the assumption that every WWTP has no motive of advanced
treatment other than water pollution control for targeted water area. But in reality some local entities might have stronger motive because they wish more for clean water in targeted or other water
areas for the benefit of their citizens. Other local entities might be willing to forward the advanced
treatment for beneficial use of the effluent. Since the behaviours of WWTPs are influenced bytheir local conditions as well as the predetermined target common to all the WWTPs, reflection of
local conditions is an important point of view from which the comparison could be made between
effluent charge system and water quality trading.
Let us add a term of local conditions si as a function of xi to eq. (1) ,myici  ¦ D k ( xi ,k  Li ,k )  si

(24)

k 1

From the equilibrium condition :wyi
wxi ,kwci
ws
 Dk  iwxi ,kwxi ,k

0

(25)

wci
ws
(26)
D k  iwxi ,kwxi ,kAs for the effluent charge system equivalent to the above water quality trading, we have

Water quality trading :myi(1  g )ci  ¦ E k xi ,k  si .
k 1

Therefore, eq. (11) is modified as:
wci
E
1 wsi
Effluent charge system : k 
wxi ,k1  g 1  g wxi , k
1 wsi
(27)
D k 
1  g wxi ,ktaking eq. (12) into account.
Since wsi wxi ,k is assumed to be positive and marginal cost related to load reductions is expressedas wci wxi ,k , comparing eq. (26) with eq. (27) gives the relation as follows:(marginal cost for water quality trading)% (marginal cost for effluent charge system)(28)
This means that local conditions are more likely to be reflected in the advanced treatment in effluent charge system than in water quality trading. In other words, effluent charge system is morefavourable for local entities that want to forward advanced treatment for their own benefit than water quality trading.

5. Conclusion
Sewerage Law was amended in 2005 and a modified approach was established by introducing theconcept of LRA for nitrogen and phosphorus in the basin of enclosed water bodies. Transferable
LRA is supposed to play a role equivalent to transferable permit in the water quality trading employed in the U.S.. Modified approach with transferable LRA is expected to substantially abate
externality-related difficulties to guide local entities toward advanced treatment, because local enti-- 102 -

ties, which can take the choice of substituting for the other local entities or being substituted for by
the other local entities on LRA, will be able to conform to the CBPSS more easily as a whole.
By means of theoretical comparison between effluent charge system (combined with subsidy) andwater quality trading, the following conclusions are obtained:(1) The mathematics for both the effluent charge system and water quality trading suggests anequivalent cost-effectiveness in meeting a predetermined target. Effluent charge system equivalent to a water quality trading could be theoretically obtained from the result of water quality trading.
(2) Water quality trading could be easily designed on the basis of the total sum of permits which isthe predetermined target of the policy, while effluent charge system cannot be designed directlyfrom the target.
(3) According to the comparison of the standard deviations of unit net cost, effluent charge systemis estimated to be superior to water quality trading in terms of equity.
(4) Local conditions are more likely to be reflected in the advanced treatment in effluent charge system than in water quality trading. In other words, effluent charge system is more favourable for
local entities which want to forward advanced treatment for their own benefit than water quality
trading.

6. Acknowledgement
The author would like to express the deepest appreciation for the useful advises toward the Study
Committee on Water Quality Trading for Pollution Control in Enclosed Waters (Chairman : Prof.
Kazuhiro Ueta, University of Kyoto).

References
1) T. H .Tietenberg : Emission Trading, an exercise in reforming pollution policy, Resources for the
Future, Inc., 1985
2) William J. Baumol and Wallace E. Oates : The theory of environmental policy, second edition,
Cambridge University Press, 1988
3) Federal Ministry for the Environment, Nature Conservation and Nuclear Safety : Environmental
Policy of Water Resources Management in Germany Part I – Fundamentals –, Federal Governmentof Germany, 2001
4) Mark S. Kieser and “Andrew” Feng Fang : Economic and Environmental Benefits of Water
Quality Trading – An Overview of U.S. Trading Program -, Workshop on Urban Renaissance andWatershed Management, organized by the Ministry of Land, Infrastructure and Transport and Shiga
Prefecture, 3, February 2004, in Otsu.

Appendix Σ
Notationci : Cost of advanced treatment for WWTP i,n

C : Total cost of advanced treatment (¦c ) ,
ii 1- 103 -

g : Subsidy rate (0 % g % 1)
Li ,k : Baseline Load of constituent k for WWTP i,qi : Effluent flow rate for WWTP i,
rk : Baseline concentration of constituent k,
si : Cost related to local conditions for WWTP i,
xi ,k : Load of constituent k discharged from WWTP i,n

X k : Total load of constituent k from WWTPs (

¦x )
i ,k

i 1

yi : Net cost for WWTP i,n

Y : Total sum of net cost (

¦y )
i

i 1

D k : Price of transferable permit for constituent k,
E k : Rate of effluent charge for constituent k,
V C : Standard deviation of unit net cost in effluent charge system,
V T : Standard deviation of unit net cost in water quality trading

Appendix ΤCase Study for Tokyo Bay
Case study of water quality trading was conducted focusing on Tokyo Bay. Constituents of pollutant were COD, total nitrogen and total phosphorus. By means of computer simulation, transferable permit of each constituent was separately traded among 75 WWTPs in the basin. Ten kindsof advanced treatment options were assumed including conventional method without advanced
treatment. Before trading, advanced treatment costs, which consisted of depreciation and maintenance costs, are calculated for every treatment option of each WWTP, taking into account the flow
rate, present treatment method and the difficulties in acquiring new site for treatment facilities.
Baseline concentration as well as flow rate of each WWTP was set referring to the study report of
CBPSS for Tokyo Bay. In the computer simulation, prices are tentatively set at first and then optimum option of advanced treatment, i.e. buying/selling permit or their combination is selected forevery WWTP so that the net cost may be minimized. At the end of the algorithmic procedure,
permit demand and permit supply are checked with each other. This procedure is continued until thecost for buying supply surplus that should be non-negative for every constituent is minimized.
Baseline Condition
After Trading
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䇭Ꮉ
✍
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䇭䇭Ꮉ

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&CKN[/CZ(NQY O㧛& 



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⠧
Ꮉ
䇭䇭ዊ
䇭♻
Ꮉ

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More Advanced
Same as Baseline
Less Advanced
No Advanced- Level104 - through Water Quality Trading
Figure 5 : Shift in Advanced Treatment

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⠧
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䇭䇭ዊ
䇭♻
Ꮉ

䇭䇭ዊ
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Figure 5 shows the result of the computer simulation. Each circle whose scale indicates effluent
flow rate corresponds to WWTP. The circle signs in the left figure show how the WWTPs change
their attitudes toward advanced treatment from the baseline as a consequence of trading. The costabatement rate of water quality trading throughout the basin is estimated to be 31% as shown in Table 1.
Table 1 : Total Cost of Advanced Treatment (million yen/year)
Baseline Permit

After Trading

Cost Abatement Rate

65,91645,79231%(Simulated for WWTPs in Tokyo Bay basin)
The effluent charge system that is designed equivalently to above water quality trading based on eq.
(17) and eq. (18) is also simulated by computer. Figure 4 is obtained by the results of the simulations.

- 105 -

- 106 -1

Source : Ministry of Environment

3

Notes :´
Figure 1 : Achievement of Environmental Standard
Notes :
1.BOD used for rivers, and COD used for lakes/reservoirs, and sea/coastal areas.
1.BOD2.Achievement
used forandCOD
for lakes/reservoirs,
and sea/coastal areas.
levelrivers,(%)=(no. of water
bodiesachieving used
/ no.of designatedwater bodies)100
Source : Ministry of Environment
2.Achievement level (%)=(no. of water bodies achieving / no. of designated water bodies)×100

Achievement of Environmental Water Quality Standard

Courtesy of Prof. Masahiko Isobe of Tokyo Univ.

Osamu FUJIKI
Research Fellow & Director of 1st Research Division
Japan Institution of Wastewater Engineering Technology

Red Tide in Tokyo Bay

Economic Instruments for Basin-wide
Efficient Pollution Load Reduction- Comparison between Effluent Charges
And Water Quality Trading -

93.0
95.4

Ise Bay
Osaka Bay

85.7

57.0

87.6

As of 2003

94.7

92.7

92.8

Target

14.1

17.3

3.6

As of 2003

Rate of Advanced Treatment(Removal of N and/or P)

産業系合計
21%

COD
（247ｔ/日）

その他系合計
11%

ＣＯＤ

生活系合計
68%

産業系合計
16%

Industrial
Wastewater

生活系合計
65%

Municipal Wastewater
Ｔ－Ｎ（254ｔ/日）

その他系合計19%

Others

Ｔ－Ｎ
Ｔ－Ｎ

産業系合計
16%

Ｔ－P
（21ｔ/日）その他系合計
20%

Ｔ－Ｐ

生活系合計
64%

4

Pollution Source Structure of Tokyo Bay (As of Fiscal 1999)

95.7

Tokyo Bay

TargetRate of the Population
Served with Sewerage

2

Source : Dr. Ando, Tokyo Metropolis

Symptom of Dying Tokyo Bay

Red Tideand Blue Tide

Pollution Sources of Three Big Bays andPresent State of Sewage Works

Red Tide- 107 -5

やる必要があるんだ。

Ｃ町下水道管理者- Town C Why
Should We, Thoughとなりの市が高度処理を
the Neighboring
Big City
やっていないのに
Does 何でうちの町が
not ?

Ｃ町

Ｄ町 下水道管理者- TownDWe Do Advanced
湖をきれいにTreatment
for the Clean
するために
Water
in Our Lake.
高度処理が必要だ。

This Wateris
住民
Tasteless.
水がまずい。

○○川

湖

Water Quality Trading

Small
Catch of Fishery
海が汚れていてBecauseof the Dirty
魚があまり取れないな。
Waters

漁師

大都市Ａ市

D町

7

Market-based approach to improve and preserve water quality

Troubled○○湾
Gulf

We Cannot
Play on the
せっかく
Beach
Because of Dirty
海浜公園があるのに汚くて遊べない。
Waters.

We Want Upstream Areas○○湾の浄化のために、
to Forward
Advanced
高度処理が必要だ。
Treatment.

Ａ市
下水道管理者- CityA-

B市- City
BB市
下水道管理者
Water Quality in Tokyo
地先の河川はきれいなのに
Bay IsNo Concern of
何で○○湾のために
Ours,
Because It Is Far
高度処理をやる必要が
From Here.
あるんだ。

Why Advanced Treatment Not in Progress ?

Source : Yambe (NGK)68• Sewerage construction/improvement programs
shall be made and implemented “in accordance
with” the relevant CBPSS•
But• CBPSS could not function as strict commandand-control measures.
•
Because• Sewerage Law postulates that CBPSS should beformulated taking cost-effectiveness into
account and it is very difficult to satisfy thiscondition.

Revenue and Expenditureof Effluent Charge inSchleswig-Holstein StateThe fund collected througheffluent charge is allocatedfor water resources andenvironment.

Effluent Charge
System in Germany- 108 11• B-3 Payment for Substitution• The local entity that substitutively fulfills the LRA
assigned for the other entity’s WWTP can, as the legal
effect of the registration in CBPSS, make the entity to be
substituted for pay the cost for the substitution including
the cost of construction, improvement, rehabilitation,
repair, maintenance and control.

• B-2 Registration in CBPSS• The prefecture that has received the proposal of
substitution can register the information of thesubstitution including the estimated cost and its sharing
in the CBPSS.

9

Moretheoreticallytheoretically•More• Basin-wide cost-effectiveness is guaranteed on thecondition of the equalization of marginal
reduction costs across all the WWTPs in the basin.
However prefectures formulating CBPSS cannot
determine the marginal reduction costs beforehandin reality.
•
Therefore• Command-and-control method cannot be easily
applied on the basis of CBPSS.

Modified
Approach
Modified
Approach

Water Quality Trading(U.S.A.)
Transferable Permit for
Discharging Pollutant
Selling Transferable Permit

Buying Transferable Permit

Modified Approach in
CBPSS (Japan)
Transferable LRA (LoadReduction Assignment)
Substituting for theother WWTP on LRA
Being substituted for by
the other WWTP on
LRA

Equivalency between Modified Approachand Water Quality Trading

12• A. Determination of the Baseline LRA• Prefecture shall determine the baseline LRA (Load Reduction
Assignment) for nitrogen or phosphorus contained in theeffluent of relevant WWTPs in the CBPSS which targets on
enclosed water bodies where EWQS (Environmental Water
Quality Standard) of nitrogen or phosphorus is set.
• B. Cooperation for Advanced Treatment between Local
Entities• B-1 Proposal of Substitution• Local entity can submit to the prefecture a proposal that it will
substitutively fulfill the LRA assigned to the other entity’s
WWTP, after reaching the agreement with the local entity to10
be substituted for on this issue.

•• Sewerage Law was amended in 2005 and a modified approach
was established••- 109 -- 50,000

鶴見川

新河岸川

10万以上50万未満
100,000-500,000
50万以上 500,000

5万以上10万未満
50,000- 100,000

5万未満

3 /日)
Daily日最大処理水量(mMax Flow (m3/D)

多摩川

入間川

荒川

隅田川

綾
瀬
川

中
川

江
戸
川

小
糸
川

Baseline Condition

小
櫃
川

養
老
川

13

鶴見川

高度処理しない
No
Advanced

現行計画よりも低いレベルの高Less
Advanced
度処理

現行計画通りの高度処理
Same
as Baseline

More
Advanced
現行計画以上の高度処理

多摩川

入間川
新河岸川

荒川

隅田川

綾
瀬
川

中
川

江
戸
川

小
糸
川

小
櫃
川

Under Economic Instrument

Shift in Advanced Treatment Level- Result of Computer Simulation for Tokyo Bay -Schematic Diagram of the Two Types of
Economic Instruments

養
老
川

15

Target of
the Policy

Baseline Load

14

Effluent Charge System

16

Effluent Charge Rate cannot determined easily

Allowable Load
(Total Sum of Permits)

Water Quality Trading

Water quality trading could be easily designed on
the basis of the total sum of permits which is thepredetermined target of the policy, while effluent
charge system cannot be designed directly fromthe target.

2. System Designing

Marginal cost for advanced treatment is equalized to for every
WWTP in both approaches.

∂c j
∂ci
=
= −α k : constant for every WWTP
∂xi ,k ∂x j ,k

• The mathematics for both effluent charge
system and water quality trading suggests anequivalent cost-effectiveness in meeting apredetermined target.

1. Equivalency in cost-effectiveness- 110 -50

3. Equity0

100,000

300,000

500,000

600,000

処理水量 m3/日

400,000

700,000

Effluent Flow Rate (m3/D)

200,000

800,000

900,000 1,000,000

Relation between Unit Net Cost
And Effluent Flow Rate

19

17

Baseline
現行方式
Permit
Water
取引方式
Quality
Trading
Effluent
負担･分配方式
ChargeThe Biggest problem related to effluent charge system is generalpublic resistance to charging/taxation.

5. Public Acceptance / Resistance

-10

0

10

20

30

Effluent charge system is estimated to be superior
40
to waterquality trading in terms of equity.

Unit 処理水量あたり自己費用
Net Cost (yen/m3)円/m3 )VielenDank

Effluent charge system
is more favourable for local entities whichwant to forward advanced treatment for theirown benefit than water quality trading.

Local conditions are more likely to bereflected in the advanced treatment in effluent
charge system than in water quality trading.

4. Equity

20

18

Design and Operation of Membrane Bioreactors in
EuropeJohannes Pinnekamp, Hiroki Itokawa, Christoph Thiemig, Aachen

1Introduction

For decades membrane processes have been used successfully in industry, forleachate treatment or for drinking water purification. The combination of biologicalwaste water treatment by activated biomass and subsequent phase separation by
membranes was described in 1969 for the first time /Stephenson, 2000/. With further
development of the low-pressure technology using immersed membranes, thetechnology of the so-called membrane bioreactor (MBR) has now arrived in municipal
waste water treatment, too. With this process, the conventional final clarification forthe separation of treated waste water and activated sludge is replaced by amembrane separation stage. The nearly germ-free effluent quality and the smaller
footprint are regarded as the most important advantages, compared to conventional
technology. As first German installation of this type for the treatment of municipal
waste water, the Titz-Rödingen waste water treatment plant was commissioned in
1999. High demands on the treated waste water were the background for theapplication of this technology. These demands could be met with the filtrate of the
MBR which did not contain solids and was nearly free of germs. The positive
experience acquired during operation but also extensive promotion of this technology
by environmental politics led to the construction of more installations, such as the
Nordkanal waste water treatment plant, at present the largest municipal MBR in
Europe with a daily waste water throughput of 16,000 m³, which was commissioned
in July 2004 /Engelhardt, 2005/. Since then the installation is a reference object for
MBR technology in municipal waste water treatment and serves national andinternational experts as model. The development of the number of installations, theircapacities and the installed membrane surface areas in Germany since 1999 ispresented in the following diagram.

Number of plants

140.000

12

120.000
100.000

910
880.0006
42

180.000
160.000

13

14

200.000

1

2

2

60.0004

340.00020.000
-

0
1999

2000

2001

2002

2003

2004

2005

2006

Year
Number of plants

Capacity- 111 -

Membrane surface

Membrane surface [m2]16

16Capacity [m3/d]

18

- /2Figure 1:

Development of the number of installations, their capacities and installed
membrane surface areas in Germany since 1999 (exept pilot plants)

Besides complete substitution of the final clarification by a membrane stage, today
the use of a MBR in a hybrid solution in parallel to a conventional waste water
treatment plant is discussed, the largest part of the annual waste water quantity
being treated in the MBR. This process presents the advantage that the costintensive membrane stage is economically exploited. However, in the case of stormwater flow, a partial waste water flow still gets into the receiving water via theconventional plant. The suitability of this process variant in practice is being tested in
The Netherlands /Mulder, 2005/.
This report summarizes the results of a Europe-wide survey of the operators ofmunicipal MBR. For this purpose an extensive questionnaire was sent to a large
number of installations in different European countries. The data collected wererecorded in a database and evaluated with view to technical equipment, operational
conditions, purification goals and success as well as operational problems
recognized up to now and approaches for their solution.
At the press date of the proceedings of this conference, not all of the questionnaires
sent were available for evaluation. Therefore mainly the results collected up to thattime are presented in the following. At present, the DWA committee of experts KA-7
is also collecting detailed data on the utilization of membrane technology for waste
water treatment in Germany. The publication of this data is to be expected in the near
future /DWA, 2006/.

2

Development of membrane technology in municipal waste water treatment

In 2000, more than 500 commercial aerobic MBR were in operation worldwide/Stephenson, 2000/. More than 3/4 of the installations serve for industrial applications,
are in-building installations or small plants for the treatment of waste water fromsingle households. Additional 9 % of the plants are used for the treatment of landfill
leachate. Only 12 % of them treat municipal waste water.
In non-European countries, membrane technology is planned and demanded in themeantime also for large waste water treatment plants as best available technology to
improve the water quality and to protect the drinking water resources. This is thecase e.g. on the Arabian Peninsula and in the U.S.A., where some MBR are plannedor already under construction which will exceed the design capacity of the Nordkanal
waste water treatment plant /Engelhardt, 2005/. But in our direct neighbourhood, The
Netherlands, too, a MBR for the treatment of the waste water from 91,000 inhabitants(1,400 m³/h) is under construction. The following diagram presents the numerical
distribution of municipal MBR and the waste water volume treated daily in Europe.

- 112 -

- /3-FRA
5

Others
9

ESP
7

FRA
3%

Others
17%

ESP
5%

Total
ITA
10

Figure 2:

GER
13

83 plants

Total

302 x10
ITA
19%

UK
39

GER
27%
3

m 3 /dUK
29%

Numbers of MBR for the treatment of municipal waste water (left and waste
water volumes treated daily (right) in Europe

Germany and Great Britain take the leading role in Europe concerning the utilizationof MBR for the treatment of municipal waste water. Meanwhile 13 municipal MBR(except pilot plants) with a total capacity of approx. 80,000 m³/d are working inGermany. These figures are exceeded only by Great Britain where MBR have been
applied since the middle of the nineties for the treatment of municipal waste water.
In 2003, already 22 installations with a total waste water throughput of approx.
88,000 m³/d were under construction or in operation in this country /Cranfield Univ.,
2006/.

3

Europe-wide survey with operators of municipal MBR

3.1

Description and way of proceeding

The project started with an investigation in the different European countries in order
to collect the contact data of the relevant installations. For the collected data, noclaim for completeness is made. In parallel with the investigation, a questionnaire in
English language was developed. It contained 51 questions to collect information ontechnical equipment, operation and operating problems recognized up to now. Since
it was asked partly for sensitive data, the operators were assured of anonymoustreatment of the data collected. For this reason no names of installations are
mentioned in the following text. The subject areas recorded by the questionnaire arecompiled in Table 1.
Since the aim was an inventory of large-scale application of MBR in municipal waste
water treatment, only installations with a daily waste water volume of at least 1,000
m³ and a minimum period of operation of one year were considered. On this basis,
25 MBR operators from seven countries in total were contacted. Some German and a
Dutch plant could be visited directly which made it easier to collect data. 14 operatorscompleted the questionnaire and sent it back. Unfortunately it was not possible tomove the operators of the remaining plants to co-operate. Therefore data from the- 113 -

- /4operation of three additional plants, although with less details, were taken fromliterature as an alternative. Thus data from 17 large-scale MBR for the treatment ofmunicipal waste water were available on the whole.
Table 1:

Contents of the questionnaire

Subject areas

Basic data

Design data

Address/contact data
Drainage system
Connected inhabitants
Date of commissioning

Reason for the choice of the MBR process
Number of lines, design flows, part ofindustrial waste water
Pretreatment, configuration of the biologicalstage, type and total surface area of themembranes, design flows, sludge treatment

General information

Subject areas

Operational data
Water quantities treated, influent and effluent
concentrations, operating conditions of thebiological stage and the membrane stage,
membrane cleaning, measuring technology,
operational problems and solutions (sieving,silting, sticking of fibrous material, floating
sludge, etc)

3.2

Results of the survey

Investment and operating costs
Energy consumption
Potential for optimization
General satisfaction with the process
Perspectives according to the operators

Within the scope of the survey concerning installations with a capacity of at least
1,000 m³/d, the ratios of the numbers of installations and capacities are similar to thetotal numbers in Europe (see Figure 2). Figure 3 shows on the left side the number ofplants divided up into size classes. On the right side, the cumulated frequency ispresented using the connection size. Again it becomes clear that Great Britain andGermany play the leading roles in Europe. The majority of the installations are in therange between 1,000 PE and 50,000 PE. The three largest installations of Europe
are in Germany, Italy and Great Britain.

- 114 -

- /5-

8

100
Germany
UK
OthersNo. plants

6

Germany
Cumulative frequency [%]

7

5
4
3
2
1

UK

80

Others60
40
20

0-1,0001,00010,000

10,00050,000

50,000-

0
100

1.000

Capacity [PE]Figure 3:

10.000100.000

Capacity [PE]

Plant capacities in different size classes according to population equivalents(PE) (left) and cumulated frequencies depending on the connection size (right)

For most operators, the reason for the choice of the MBR process was the smaller
footprint, followed by the improved effluent quality. In some cases the plants served
as demonstration object in the respective country in order to acquire first experience
with the technology or to make the introduction of MBR technology to the market
easier.
3.2.1 Inflow conditions
The ratio of the maximum dry weather flow per hour or the maximum storm-waterflow related to the mean dry weather flow respectively is an important factor for thedesign of a MBR because the necessary membrane surface area has to be
calculated according to the maximum inflow water quantity. The higher this ratio, themore unfavourable is the capacity utilization of the membranes which are aconsiderable part of the investment costs. These rations are represented in Figure 4.
For four installations, the ration is nearly 1, thus optimal for MBR operation. In themost unfavourable case, the inflow during storm-water flow is higher by the factor 7
than the mean dry weather inflow.

Cumulative frequency [%]

100
80
60
40
Dry weather

20

Wet weather
0
0

1

2

3

4
Peak factor [-]- 115 -

5

6

7

8

- /6Figure 4:

Ratio of dry weather peak or storm-water peak respectively and mean dry
weather flow

3.2.2 Pretreatment
Pretreatment measures are essential for MBR operation, since the membrane
modules, depending on the type, are susceptible to silting or sticking of fibrous waste
water
contents.
Thefollowing
diagramsinFigure5
showthe„conventional“ pretreatment measures such as coarse screen, grit chamber/grease
trap and primary clarification (left) as well as the slot widths of fine sieves for waste
depending on the membrane type used (right).
100

Flat sheet

80

Hollow fiber

100
80

[%]

60

none

60

2.5~

[%]

40
20

1.0~2.540~1.0

Figure 5:

OthersPrimary
sedimentation

Coarsescreen

Oil
trap

Grit
chamber0200Flat sheet

Hollow fiber

Conventional pretreatment measures (left) and fine sieving of the waste water
depending on the membrane type used (right)

It can be seen clearly that smaller slot widths are normally used in plants equippedwith hollow-fibre modules because these modules are more susceptible to sticking
and clogging of fibrous material.
Besides the pretreatment steps presented, some operators of hollow-fibre modules
additionally use a so-called bypass sieving of the activated sludge. This means that a
partial flow of the recycled sludge is submitted to sieving with slot widths of > 0.5 mm
in order to remove more inhibiting substances from the bioreactor.
3.2.3 Operation of the activated sludge stage
The process of upstream denitrification predominates when choosing the operating
mode of the plants with view to carbon and nitrogen removal. In Great Britain, mostplants are continuously aerated, since in this country no demands are usually madeon the effluent values for nitrogen and phosphorus (Figure 6, left). Only one of theplants was designed for increased biological phosphorus removal. In the plants
where the phosphorus effluent values are controlled by precipitation, no special
precipitant is used (Figure 6, right).

- 116 -

- /79Figure 6:

7

Fullaerobic
7

Total
17 plants

With
P-precipitation

6
5
4
3
2
1

Bio-P

Intermittent
aeration

Predenitrification0
Full
aerobic

Predenitrification
8

Without
P-precipitation

8

No. plants

Intermittent
aeration
1

Bio-P
1

Operating mode of the plants: total numbers (left) and with/without P
precipitation (right)

The solid matter concentrations in the activated sludge tank of the plants on theEuropean continent are predominantly between 10 and 12 g/l. In Great Britain, thesevalues are between 7 and 15 g/l. Concerning the hydraulic retention time which isfrequently used in the design of a MBR /MUNLV, 2003/, the data vary significantly.
Related to dry weather flow, they are between 2.8 and 16 hours (Figure 7, left). But
these retention times not always coincide inevitably with the critical design case.
100
Cumulative frequency [%]Cumulative frequency [%]

100
80
60
40
For capacity

20

80
60
40

With
separate filtration

20

Without
separate filtration

For daily average
0

0
0

10

20

30

Biological stage HRT [h]Figure 7:

0

5

10

15

20

Total HRT for capacity [h]Hydraulic retention times: activated sludge tank only (left) and including
filtration stage (right)

In Figure 7 (right), the retention times including the volumes of separate filtration
tanks are presented. It is striking that the plants equipped with a separate tank for themembrane modules (55 % of all plants) not inevitably require a larger total tankvolume (resulting in a longer retention time).

- 117 -

- /83.2.4 Operation of the membrane stage

100

100

80

80

Cumulative frequency [%]Cumulative frequency [%]The flow rates which can be attained on average are another important factor for theassessment of the cost-effectiveness of a MBR. In Figure 8 (left), the average flow
rates determined by calculation and the maximum flow rates attained briefly under
wet weather conditions are presented. The broad range of these values shows here,
too, significant site-specific differences (cf. chapter 3.2.1 Inflow conditions). On theright side, the specific air requirement for the control of the covering layer isrepresented. The higher air requirement of the plate modules becomes clear.
However, the manufacturers currently develop modules to reduce these values
because this co-called cross-flow aeration has a decisive share in the overall energy
costs.

60

40

Maximum flux

20

60

40

20

Flat sheet

Daily average flux

Hollow fiber

0

0
0

20

40

60

2

0,2

0,4

0,6

0,8
3

1,0

2

Specific air requirement [Nm /m /h]

Flux [L/m /h]

Figure 8:0,0Flow rates (left) and air requirement for covering layer control (right) dependingon the membrane system used

Concerning membrane cleaning, one distinguishes two strategies. The so-called
maintenance cleaning is carried out in intervals of one or two weeks in order tomaintain the permeability, i.e. the filtration capacity of the membrane. An oxidative
cleaning solution (mostly NaOCl) is introduced into the membrane from the permeate
side. Most of the operators carry out an acid cleaning as second step.
In most of the plants, a so-called recovery cleaning is carried out once up to fourtimes a year to counteract the inevitably progressing reduction of the permeability.
This is done in nearly the same way as the maintenance cleaning described above,
but with cleaning agents in higher concentrations.
Irrespective of the strategy, cleaning can be carried out in different ways. With in-situ
cleaning, the membranes remain immersed in the activated sludge. Better cleaning
results are attained with the so-called on-air cleaning. For this purpose, the modules
remain in the tank and the sludge level is lowered to the bottom edge of the module.
This procedure requires separation of the tank zones (activation zone – filtrationzone). The best cleaning results are attained with the so-called soaking. This meansthat the modules are immersed completely for several hours into a cleaning solution.

- 118 -

- /9However, either the activated sludge has to be removed and the cleaning solution
has to be filled into the membrane chamber, which requires a corresponding
arrangement of the tanks like in on-air cleaning. Or the modules are lifted from theactivated sludge tank into a separate washing cell where the cleaning takes place.
Since this is the most expensive cleaning method, it is only used for recovery
cleaning.
Two of the 17 plant operators questioned told us that they carry out the cleanings
described with H2O2 instead of NaOCl. This proceeding has the advantage that theeffluent is not charged with organic halogenated compounds. However, the otheroperators still prefer NaOCl as cleaning agent because of better cleaning results intheir plants.
Concerning membrane cleaning, there are clear differences depending on themembrane system used. Hollow-fibre membranes are usually cleaned by a
combination of maintenance and recovery cleaning, while it is done withoutmaintenance cleaning for plate membranes. Table 2 presents the cleaning methods,
chemicals and their concentrations depending on the membrane system as well as
data on the operating cycles of the membranes of eleven different plants.
Table 2:

Maintenance cleaning

Betriebszyklen

Kläranlage
Membrantyp

Cleaning strategies depending on the membrane system
1
PlatteRecovery cleaning

3
Hohlfaser4
Hohlfaser5
Hohlfaser

6
Hohlfaser

7
Hohlfaser8
Hohlfaser9
Hohlfaser10
Hohlfaser

11
Hohlfaser

Filtrationszeit [s]

540

400

200

500

k.A.

k.A.

300

k.A.

k.A.

360

300

Pause [s]60 (+30s)

0

0

1

k.A.

k.A.

0

k.A.

k.A.

0

5

Rückspülung [s]

-

15

50

k.A.

k.A.

30

k.A.

k.A.

20

25

Methodenie

50
On air +In-situ

On airOn airIn-situIn-situIn-situIn-situIn-situ

On airOn airFrequenz-

1/Woche0.51/Woche

ErstesReinigungsmittel-

Zitronensäure(+HCl)

NaOCl

Konzentration [ppm] -pH=2

Zweites
Reinigungsmittel

NaOCl

-

Konzentration [ppm] -Grundfür RC2
Hohlfaser

500

250-500
Zitronensäure
jeweils
berechnet

Soaking(sep.Tank) 1/Jahrnie
Zitronensäure(+HCl)

0.5/Woche 1/Woche k.A.
NaOCl
(1+2.
Woche)
Zitronensäure(3. Woche) H2O2
H2 O 2k.A.

1/Woche

NaOCl

NaOH

NaOCl

NaOCl

NaOCl

700
(NaOCl)
30000(Zitronensäure)

k.A.

200

k.A.

500

800

250

k.A.

Zitronensäure

Zitronensäure

k.A.

k.A.

Zitronensäure

HCl

300

k.A.

k.A.

k.A.

k.A.

k.A.

3200

675

Soaking(in situ)
2/JahrSoaking(sep.Tank) 1/Jahrnie

Soaking(in situ)
1/JahrSoaking(sep.Tank) k.A.
k.A.
2/Jahrnie

Soaking(in situ)
1-2/Jahr

NaOCl

-

NaOCl

k.A.

NaOCl

-

NaOCl

Zitronensäure-

Zitronensäure

k.A.

k.A.

-

Zitronensäure

0
1
0

k.A.
k.A.
k.A.

0
0
1

1
0
0

k.A.
k.A.
k.A.

0
0
1

1
0
0

300
Zitronensäure(+HNO3)

MethodeFrequenz

Soaking(in situ)
4-5/Jahr

ErstesReinigungsmittel

NaOCl

Zweites
Reinigungsmittel

Oxalsäure
(C2O4H2) NaOCl-

H2 O 2Zitronensäure(+HNO3)TMP
fester Zeitpunkt
Andere

1
0
1

0
0
0

0
1
0

0
0
1

1/Woche

1/Woche(Winter)
0.5/Woche(Sommer) 1/Woche- 119 -

- / 10 3.2.5 Purification capacity
Figure 9 (left) presents the ratio of the maximum inflow concentration and the meanvalues. The inflow concentrations in part vary significantly. The average COD inflow
concentrations are in a range between 232 mg/l and 700 mg/l. The COD peak load
also shows a broad range (from 508 mg/l to 2140 mg/l). This also applies for thenitrogen and phosphorus concentrations. Nevertheless, all MBR are able to efficiently
remove organic substances and nutrients. Nearly all plants attain average COD
removal rates of > 90%. Figure 9 (right) presents the removal rates for COD, total
nitrogen and total phosphorus as cumulated frequencies.
100
Cumulative frequency [%]Cumulative frequency [%]

100
80
60
40
COD
T-N

20

T-P
0

T-N
T-P

60
40
20
0

0

2

4

6

Influent peak/average ratio [-]Figure 9:

COD
80

0

20

40

60

80

100

Average removal efficiency [%]Ratio of inflow concentrations (left) and removal capacity (right)

3.2.6 Operating problems, approaches for solutions and need for optimization
When introducing a new technology, most different operating problems usually occur
during the first years which cannot be foreseen or only to a limited extent when
designing the plants. In the case of MBR, the following “classical” operating problems
with possible approaches for solutions can be identified:x

Problems with fine sieving of the waste water Î to be optimized by the screen
manufacturers (in cooperation with the operators)x

Problems with the membranes due to insufficient fine sieving of the waste
water (sticking of fibrous material) Î change of the type of sieve, reduction of
the slot widths, sieving of partial sludge flowsx

Problems with the membranes by insufficient aeration (silting) Î optimizationof module aeration or to be optimized by the module manufacturerx

Damages at the membrane modules Î to be optimized by the module
manufacturer, more careful handling of the modules during operation andcleaning- 120 -

- / 11 x

Strong development of floating sludge Î skimming, spraying, utilization ofpolymers, “ignoring“xAir in the permeate pipe Î constructing the permeate pipes ascending to thepump, vacuum pumpx

Problems with the control software Î to be optimized by the software
producer in cooperation with the operators

Besides these general operating problems, some special proposals and remarks ofthe operators should be considered when planning MBRs:x

The membrane modules should be arranged in separate tanks. The
advantages of cleaning compensate the disadvantages from operationx

The permeate pipes should be designed as short as possible in order toreduce the periods of backwashing.

x

The number of racks per unit should be small, and the permeate pipes to theunits should have uniform lengths. This ensures homogeneous feeding of themembranes with the cleaning solution.

x

The permeate pipes should be made of plastic. This helps to avoid corrosion
due to cleaning agents.

From the operators’ point of view, there is still general need for optimization of theplant operation. The above problems and remarks were the most frequently
mentioned ones and, with this, at the same time an appeal to the researchers:

4x

To lower the energy demandx

To optimize the pretreatment in order to ensure stable MBR operationx

To make chlorine-free cleaning possible

Summary and outlook

Within a few years, the MBR technology has become a promising alternative forconventional technology. At present, more than 80 large-scale MBRs are in operationin Europe. Some more large-scale plants are in planning stage or already underconstruction.
The survey carried out had for result that most of the operators are quite satisfied
with the efficiency of their plants. The operating problems mentioned areunderstandable, since the technology is still new, but they seem solvable. For thispurpose, however, plant operators, membrane manufacturers, consulting engineers
and research institutions have to cooperate closely. In Germany, approaches in thisfield already exist. Within the framework of conferences and workshops, organized by- 121 -

- / 12 university institutes, water boards or DWA, engineers and scientists get theopportunity to exchange and discuss their experience. First publications give
instructions for design and operation of MBRs. The book “Membrane Technology for
Waste Water Treatment”, edited by MUNLV NRW /MUNLV, 2006/ and the work
reports of the committee of experts KA 7 of DWA /DWA, 2005/ are to be mentioned
here. The development of an internet-based data base for the collection of all
relevant data in this field would be a possibility to improve cooperation in Europe.
These data might serve as ideal basis for coordination and planning of additional
research activities.
With the construction of the Nordkanal WWTP, it was demonstrated that the MBR
technology can be mastered on a large scale and can be used efficiently. The
question is now: Which perspectives has this process concept in Europe? The
political and legal boundary conditions concerning the demands on the effluent
quality will surely influence the membrane market in a positive way. Within thesebounds, the IVU and the Water Framework Directive have to be mentioned. Thus it
can be expected that the number of membrane installations in Europe will increasesignificantly from 2010 on within the scope of the implementation of water protection
measures. The reasons are not only the high capacity for nutrient removal and thenearly germ-free effluent quality of MBRs. Since it is aimed at reducing priority
substances in surface waters, the solid-free effluent, ensured by the membranes,
offers ideal prerequisites for the use of downstream treatment steps such as
ozonation or active carbon filtration.
The market research institute „Frost & Sullivan“ has found out that the biggest
challenge for the membrane manufacturers is to persuade the decision-maker in themarket of the possibilities of the MBR process and to show them which benefit thecustomer may derive from them /Frost & Sullivan, 2005/.
Integration of the MBR into the conventional technology, as it is the case with thehybrid solution, or complete replacement of the final clarification by the MBR – from
European legislation concerning purification requirements, but also from the purely
technical advantages of the process it can be expected that the market for MBR in
municipal waste water treatment in future will increase.
Acknowledgements:
We express our thanks the participants of the survey who have compiled allnecessary data for the extensive questionnaire and who have given information in apatient way during long conversations, and the Federal Ministry of Education andResearch for the promotion of the project.

- 122 -

References:/Cranfield Univ., 2006/ Cranfield University, UK:
http://www.cranfield.ac.uk/sims/water/memnet/uk_membrane_municipal_plant.html, Last access:January 2006
/DWA, 2005/

Deutsche Vereinigung für Wasser, Abwasser und Abfall e.V.,
DWA: 2. Arbeitsbericht des Fachausschusses KA-7
“Membranbelebungsanlagen, KA – Abwasser, Abfall 2005(52) Nr. 3; ISSN 1616-430X, (2005)/DWA, 2006/

Deutsche Vereinigung für Wasser, Abwasser und Abfall e.V.,
DWA: Auskunft des Fachausschusses KA-7, (2006).

/Dohmann, 2005/

Dohmann, M: Perspektiven für den Einsatz der Membrantechnik in der Abwasserbehandlung, Beitrag zur 6. Aachener
Tagung Siedlungswasserwirtschaft und Membrantechnik(2005)/Engelhardt, 2005/

Engelhardt, N: Das Gruppenklärwerk Nordkanal nach einem
Jahr Betrieb – eine Perspektive für große Membranbelebungsanlagen, Beitrag zur 6. Aachener Tagung Siedlungswasserwirtschaft und Membrantechnik (2005)/Frost&Sullivan, 2005/ Frost & Sullivan Research Report: Strategic Analysis of theEuropean Membrane Bioreactor Markets (2005),
http://www.frost.com/Mulder, 2005/

Mulder, J. W., v. d. Berkmortel, H., Kramer, F.: Hybrid-MBR –Ein neues konzept für die Abwasserbehandlung, Beitrag zur
6. Aachener Tagung Siedlungswasserwirtschaft undMembrantechnik (2005)/MUNLV NRW, 2006/

Ministerium für Umwelt und Naturschutz, Landwirtschaft undVerbraucherschutz des Landes Nordrhein-Westfalen:
Membrantechnik für die Abwasserreinigung, Erschienen im
FiW-Verlag, ISBN 3-939377-00-7 (2006)/Stephenson, 2000/

Stephenson, T., Judd, S. J., Jefferson, B., Brindle, K.:
Membrane Bioreactors for Wastewater Treatment. IWA
Publishing, London (2000)/Stephenson, 2003/

Stephenson, T.: Membrane Technology for Wastewater
Treatment and Reuse - State of the Art and future
Prospectives, Beitrag zur 5. Aachener Tagung Siedlungswasserwirtschaft und Membrantechnik (2003)- 123 -

- 124 -Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

Design and Operation of Membrane Bioreactors in Europe¨ Far more applications in a range of industries(e.g. textile, brewery, food...)¨ Typically applied in conjunction with water reuseIndustrial WWT¨ First application in 1999 (Rödingen WWTP, 3,000 PE)¨ Presently, 12 plants are operated, 4 plants are underconstruction/design¨ Principal reasons for application are to meet the effluent
quality regulation and to reduce tank volume

Municipal WWT

MBR application in Germany

Design and Operation of Membrane Bioreactors in Europe

Institute of Environmental Engineering
RWTH Aachen University

Univ.-Prof. Dr.-Ing. Johannes Pinnekamp
Dr.-Eng. Hiroki Itokawa
Dipl.-Ing. Christoph Thiemig

Design and Operation of
Membrane Bioreactors in Europe

3

1

Environmental Engineering RWTH Aachen University
Environmental Engineering RWTH Aachen University

kWh/m³Specific energy
consumption

2004
2004

Seelscheid

10,5002,600

80,000

700

9,700

2,310

730

9,200

136

1,640

68

1,800

190

480

Kubota

ZENON

ZENON

PURON

ZENON

Martin Systems

ZENON

KubotaZENON

ReactorMembranevolume [m3]supplier

Design and Operation of Membrane Bioreactors in Europe

2003

Nordkanal
Schramberg

2003

Monheim

2003

2001
Simmerath

8,000

2000

Markranstädt
Knautnaundorf

900

1,000

1999

Büchel3,000

Capacity[PE]
1999

Start-up
Rödingen

Name

Existing municipal MBR plants in Germany

Design and Operation of Membrane Bioreactors in Europe

0.7 – 1.5

< 20

<5

g/L

MLSS

0.2 – 0.4

bathing water quality

mg/L

Ptot (with simultaneous
precipitation)
No bathing water
quality

< 13

< 13

mg/L

Ntot

Microbiological quality< 30

40 – 50

mg/L

COD

< 0.3

0

10 – 15

mg/L

Suspended Solids

0.8 – 1.0

Membrane Bioreactor

Conventional activatedsludge plantParameter

Performance data of membrane bioreactor plants
compared to conventional activated sludge plants

42

- 125 -Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

5

Source: Erftverband 20027

Conventional plant

Design and Operation of Membrane Bioreactors in Europe

Membrane bio-reactor plant

Example of municipal MBR application(Nordkanal)
Nordkanal)

Design and Operation of Membrane Bioreactors in Europe¨ Increased requirements for the effluent quality- EU Water Framework Directive- EU Directive on Bathing Water- Sensitive receiving water bodies- WWTP effluent in drinking water protection zones¨ Local situation (space requirement)¨ Introduction of new technology¨ Financial support by local governments¨ Technical improvement of immersed membrane
modules¨ Increased knowledge & experience from existingplans

Driving forces for MBR application inGermany
Environmental Engineering RWTH Aachen University
Environmental Engineering RWTH Aachen University

Step screen
5 mm
Emergency
bypassscreen1 mm

Rotaryscreen0,5 mmRecirculation

Nitrification,
membrane stage

Blowerinstallation

Flow

mg/l
mg/l
mg/l

NH4-N
Ntot
Ptot

< 0,5

?

<2

<5

< 25

Discharge consent(at T<10°C)

6Design and Operation of Membrane Bioreactors in Europe

Source: Erftverband 20028¨ An energy demand approx. 60 % (0.8 kWh/m³) higher than forconventional plants (0.51 kWh/m³) can be expected¨ The investment was 21.5 million €.
¨ Approx. 6.6 million € of this amount had been taken over by thefederal state North-Rhine Westphalia.

2

18

10

90
20

mg/l
mg/l

Minimum
requirements
BOD5

Unit
COD

Parameter

Minimum requirements and discharge consent of the Nordkanal WWTP

Example of municipal MBR application(Nordkanal)

Design and Operation of Membrane Bioreactors in Europe¨ Largest in Europe(80,000 PE = approx.10,000 m3/d, 84.000 m² membrane surface)¨ Operated since December 2003

Feed

Grit
chamber

Denitri- Variablefication zone

Example of municipal MBR application(Nordkanal)

- 126 -

1

2

2

3

4

9

Number of Plants

1999

2000

2001

2002

2003

2004

2005

2006

(Without pilote plants)
Design and Operation of Membrane Bioreactors in Europe02020.00040.00060.0006

480.000100.000

120.000

8

10

12140.000

14
13

160.000

16

18

16

180.000

Membranfläche
Membrane
Surface200.000

Kapazität
Capacity

20

Anlagenzahl
Number of Plants

Development of Plant Number in Germany

Design and Operation of Membrane Bioreactors in Europe

Capacity [m3/d] Membrane area [m2]11

9Environmental Engineering RWTH Aachen University
Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

WWTP Kaarst/Nordkanal

Numberof Plants
Anlagenzahl

2

2

3

5

9

13

Capacity
Kapazität

20

41

61

82

Membrane Surface
Membranfläche

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

1

Design and Operation of Membrane Bioreactors in Europe(Ohne Pilotanlagen)Without
Pilote Plants

0

10

20

30

40

50

60

70

80

90

Numberof Plants
Anlagenzahl

040.00080.000120.000

160.000

200.000

240.000

280.000

320.000

360.000

Development of Plant Number in Europe

Design and Operation of Membrane Bioreactors in Europe

Membrane installation at the WWTP
Nordkanal

10

Source: Erftverband 2002

12

Kapazität[m³/d]
Membranfläche] [m²]
Capacity[m³/d]
Membrane
Surface [m²Area- 127 -Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

GER
13

UK
38

3
5

And.
17

ITA
19

%

GER
27

Anlagenzahl
Numberof Plants-1,00010,000-50,000

Capacity [PE]Kapazität[EW]

1,000-10,000

Deutschland
Germany
UK
UK
AndereOthers

50,000-Design and Operation of Membrane Bioreactors in Europe

0

1

2

3

4

5

6

7

8

Size Distribution

UK
29

Capacity
Total: 302,000 m³/d

Design and Operation of Membrane Bioreactors in Europe(Without pilote plants)

And.
9
FRA
5
ESP
7
ITA
10

Number of Plants
Total: 82

15

13

Environmental Engineering RWTH Aachen University
Environmental Engineering RWTH Aachen University

Plant Number and Capacity

10.000Kapazität [PE]Capacity
[PE]

1.000

Germany
Deutschland
UK
UK
OthersAndereDesign and Operation of Membrane Bioreactors in Europe

100

0

20

40

60

80

100

Participants in the Survey

100.000

 Costs
 Optimization Potentials
 Contentedness Perspectives¨ General Information

Design and Operation of Membrane Bioreactors in Europe

 Reason for MBR
 Design Flow Industrial WW Flow
 Number of Lines Pretreatment
 Configuration of Biol. Reactor
 Type and Design ofMembranes Sludge Treatment¨ Design Data

16

14

 Flow
 In- and Outflow Concentrations
 Operational Conditions
y Biological Reactor
y Membranes
 Membrane Cleaning Measuring Operational Problems
 Lessons Learned¨ Operation Data

Content of Questionnaire Address/Contact Data
 Sewerage System
 Capacity
 Start of Operation¨ Basic Data

Kumulierte
Häufigkeit
Frequency[%][%]

- 128 -Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

0

20

40

60

80

0

2

4

Peak Factor [-]Peak factor [-]6

Wet weather

Dry weather

Plattenmodul
Flat
Sheet Mod.

1.0~2.5

keine

Hohlfasermodul
Hollow
Fiber Module

2.5~

Design and Operation of Membrane Bioreactors in Europe

0

20

40

60

80

100

~1.0

Fine Screen as Pre-Treatment

Design and Operation of Membrane Bioreactors in Europe

Cumulative Frequency
frequency [%] [%]Cumulative

Anteil [%]

8

19

17

Grob
CoarserechenScreen

Fett
Oil
fang
Trap

Sand
Grit
fang
Chamber

Anteil [%]Hohlfasermodul
Hollow Fiber M.

Plattenmodule
Flat Sheet Mod.

Total:
17 Plants

1

Bio-P

7

Contin.
aeratedDesign and Operation of Membrane Bioreactors in Europe

PreDenitrif.
8Interm.
Denitrif.
1

Operation of Biological Stage

Design and Operation of Membrane Bioreactors in Europe

0

20

40

60

80

100

Pre-Treatment Technologies

Primary
Vorklärung
Sediment.

100

Environmental Engineering RWTH Aachen University
Environmental Engineering RWTH Aachen University

Influent Variation

AndereOthers20

18

Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

0

12

18

24

Aufenthaltszeit
in derStage
biologischen
Stufe [h]Biological
HRT [h]6Fordaily Mittel
im täglichen
AverageFor
bezogenauf dieGesamtkapazität
Capacity

0

10

20

30
2

Design and Operation of Membrane Bioreactors in Europe

Flux [L/m /h]

40

50

Daily
Flux Average
im täglichen
Flux
Mittel200Maximaler
Flux
Maximum
Flux

40

60

80

100

Maximum and Average Flux Rates

Design and Operation of Membrane Bioreactors in Europe

0

20

40

60

80

100

Biological Stage HRT [h]

21

23

60

30

Environmental Engineering RWTH Aachen University
Environmental Engineering RWTH Aachen University

KumulierteFrequency
Häufigkeit [%]Cumulative[%]

Kumulierte Frequency
Häufigkeit [%]Cumulative
[%]

0

2

4

6

8

10

Total HRT [h]Gesamtaufenthaltszeit [h]

12

14

0,2

0,6

0,8

Specific
Air Requirements[Nm²/m³/h]
Spezifischer
Luftbedarf [Nm³/m²/h]

0,4

Hohlfasermodul
Hollow Fiber M.

Flat Sheet Mod.
Plattenmodul

Design and Operation of Membrane Bioreactors in Europe

0

20

40

60

80

100

1,0

Air Requirements for Covering Layer Control

16

Module im
Without
separate
Belebungsbecken
Filtration

20
0

With
separate
mit separater
Filtration
Filterstufe

40

60

80

100

Total HRT [h]Design and Operation of Membrane Bioreactors in Europe

KumulierteFrequency
Häufigkeit [%]Cumulative[%]

Kumulierte Häufigkeit]
Cumulative
Frequency[%[%]- 129 24

22

18

- 130 -Environmental Engineering RWTH Aachen University

Environmental Engineering RWTH Aachen University

0

1

2

3

4

Kumulierte Häufigkeit [%]Effluent

Design and Operation of Membrane Bioreactors in Europe

Pretreatment
Optimal MLSS-conc.
Excess sludge production
Sludge properties
Aeration efficiency (α-value)
Hydraulic behaviour(Min. hydr. retention time)
Floc structure, Foaming
Pretreatment
etc….

1. Biological Process

Inflow

Research Topics

Design and Operation of Membrane Bioreactors in Europe

Zulaufkonzentrationen:
Verhältnis Ratio
Spitze/Mittelwert[-]
Influent Peak/Average[-]

5

Total-P

20

0Total-N

CSB

40

60

80

100

6

27

25

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Environmental Engineering RWTH Aachen University

Variation of Inflow Concentrations

0

20

40

60

80

100

20

30
40
50
60
70
80
90
Durchschnittliche[%]
TreatmentEliminationsleistung
Efficiency [%]Total-P

CSB
Total-N

Treatment Efficiency [%]Material
Pore size
Flow, permeability
Fouling, scaling
Cleaning
Costs
Life spanetc….

2. Membrane

Effluent

Design and Operation of Membrane Bioreactors in Europe

Inflow

Research Topics

Design and Operation of Membrane Bioreactors in Europe

Cumulative[%]
Kumulierte Frequency
Häufigkeit [%]

100

28

26

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Post-treatment
etc….

Degradation
Transformation
Adsorption
Filtration

MembraneMembrane
Replacement
Costs [€/m²]
replacement costs €/m2

1995
Year

Year

WWTP Markranstädt
8.000 E
joint WWTP
Nordkanal
80.000 E

WWTP
Knautnaundorf
900 E

2000

WWTP Rödingen
3.000 E

according to Churchhouse(2000)

Design and Operation of Membrane Bioreactors in Europe

0
1990

50

100

150

200

250

300

350

400

450

Cost Development

2005

Conventional parameters
Hygienic quality
Organic trace pollutants
Mechanisms

3. Treatment Efficiency

Effluent

Design and Operation of Membrane Bioreactors in Europe

Inflow

Research Topics

31

29

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Energy Demand
Costs
Life Cycle Analysis
Automation and Control……….

4. Whole Process

Effluent

Design and Operation of Membrane Bioreactors in Europe

Design and Operation of Membrane Bioreactors in Europe

Inflow

Research Topics

32

30

Japanese㩷Experience㩷of㩷MBR㩷Application㩷to㩷Municipal㩷Wastewater㩷

Takao Murakami*, Shuji Oota*, Yasuyuki Nakasuji*
㧖R&D Dept., Japan Sewage Works Agency, 5141 Shimo-sasame, Toda, 335-0037 Japane-mail: murakamit@jswa.go.jp

Abstract
The introduction of MBRs has lagged behind compared with other fields of wastewater management inJapan, but four MBR plants started operation successively in 2005. MBR is expected to be increasingly
used for municipal wastewater treatment. Although MBR has been used mainly for small scale plants so far,it will likely be applied to larger plants in the future. The MBR is not merely one of many wastewater
treatment technologies, but is regarded as a core technology that offers various possibilities. In this context,
the research results of virus removal, excess sludge reduction, odor emission and application to BNR
process of MBR were introduced.

Keywords: MBR, municipal wastewater, virus, odor, excess sludge, BNR
Introduction
The membrane bioreactor (MBR) is a wastewater treatment technology that offers many
advantages. In Japan, although MBRs have long been used for industrial wastewater treatment
or for reuse of wastewater in large buildings and so on, the introduction of MBRs in seweragesystems has lagged behind compared with other water related fields. However, the first MBR
for municipal wastewater treatment in Japan started operation in March 2005, and this will
accelerate the introduction of MBRs in Japanese sewerage systems. This paper reviews thepresent state and perspectives of MBRs for municipal wastewater treatment in Japan andintroduces some of JSWA¶s researches on MBR.
Characteristics of MBRs in Japan
Characteristisof J apanese municipal sewer system
The characteristics of Japanese municipal sewer system, to which MBR are applied, are as
follows;
1) Most of sewer system are separate system with the exception of large scale cities.
2) The strength of raw wastewater is rather weak; BOD 200mg/L, SS 170mg/L, T-N 35mg/L,
T-P 5mg/L on average.
3) In the middle and small-scale sewer systems, household wastewater occupies the mostpart.
4) Even in separate sewer systems, considerable amount of infiltration into sewer is- 133 -

sometimes observed in rainy weather.
5) In small-scale sewer systems, the flow fluctuation is usually high, so that the peak flow
amounts to three times of the average flow.
F low of process
Considering some of the above mentioned characteristics of Japanese municipal sewer system,
the basic flow of the MBR for municipal wastewater is as shown in Figure 1.[1]㪠㫅㪽㫃㫆㫎

㪈㫄㫄㩷㫊㪺㫉㪼㪼㫅㪚㪿㪼㫄㫀㪺㪸㫃㩷㪽㫆㫉㪙㪸㪺㫂㫎㪸㫊㪿

㪚㫆㪸㪾㫌㫃㪸㫅㫋㪜㫈㫌㪸㫃㫀㫑㪸㫋㫀㫆㫅㪫㪸㫅㫂㪘㫅㫆㫏㫀㪺
㪫㪸㫅㫂㪜㪽㪽㫃㫌㪼㫅㫋
㪤㪼㫄㪹㫉㪸㫅㪼
㪛㫀㪽㪽㫌㫊㪼㫉

㪤㫀㫏㪼㫉㪚㪿㪼㫄㫀㪺㪸㫃㩷㫎㪸㫊㪿㫋㪸㫅㫂㪙㫃㫆㫎㪼㫉

㪜㫏㪺㪼㫊㫊㩷㫊㫃㫌㪻㪾㪼

Figur e 1 㧦The basic flow of MBR for municipal wastewater
Pretreatment
Inflow wastewater passes through a fine screen to remove coarse materials. Although a 1-mm
screen is standard, a finer screen is required for some types of hollow fiber membrane
modules. On the other hand, a coarser 2-3mm screen will suffice for some flat sheet
membrane modules. In one pilot-plant study that treated actual wastewater of a separate sewer
system, it was shown that fibers, vegetable residues and hairs were the main components ofscreen debris, with the amount of debris collected on a 1-mm screen being about 27g/m3 as
wet weight and 3g/m3 as dry weight.
F low equalization
The MBR is expected to be used mainly for small facilities for the present in Japan. Since theinflow volume fluctuates greatly in a small sewer, it is necessary to stabilize the permeate fluxof the membrane module by using a flow equalization tank. The tank requires an HRT ofabout 4.5 hours based on the average flow.

- 134 -

Bioreactor
The bioreactor consists of an anoxic tank and an oxic tank. The membrane module isimmersed in the oxic tank. The HRT of the anoxic tank and the oxic tank are each 3 hours,
giving a total of 6 hours for the bioreactor. The mixed liquor is circulated from the oxic tankto the anoxic tank. Since nitrification advances in the oxic tank and pH falls by alkalinity
consumption, the circulation helps to restore alkalinity through denitrification in the anoxic
tank. Biological nitrogen removal can be achieved by circulation. The nitrogen removal ratio
is determined theoretically by the circulation ratio.
Membrane module
For MBR, an MF membrane module with a pore size of 0.1±0.4 ȝm is usually used. In thedesign of MBR, the reactor tank is designed first and then the tenderer decides the type ofmembrane module.
Membrane modules are divided broadly into two categories: flat sheet (FS) and hollow fiber(HF). At present in Japan, flat sheet modules are used more commonly than hollow fiber
modules. In the hollow fiber membrane module, new membrane modules are actively being
developed and high permeate flux, long-length vertical membrane modules made of PVDF or
PTFE are now becoming the mainstream of hollow fiber modules.
As one of the newest membrane modules, the monolith type ceramic MF membrane module
has appeared recently. The monolith type module, which has a complicated pore structure, hasalready been introduced in the treatment of drinking water. Although the cost is still high andthe module is considerably heavy, the ceramic module offers high flux and high durability, orlong lifetime, and is expected as an effective tool in reducing membrane replacement costs.
Membrane life is an important factor that greatly influences the running cost of MBR.
Judging from the various experiences of domestic and overseas MBRs treating sanitary
wastewater, the membrane made of organic materials typically lasts at least seven years. In
Japan, since the cost of replacing the membrane module after ten years of use is subsidized,
ten years is regarded as the target membrane life.
Other equipments
Since no Escherichia coli is detected in the effluent, no disinfection equipment is installed. In
the figure, flocculant dosing equipment is installed when phosphorus removal is necessary.
Biological phosphorus removal is also possible by preparing an anaerobic zone in thebioreactor. Since the MBR is operated at a high MLSS concentration, the negative influencesof DO on the anaerobic zone caused by mixed liquor circulation can be rapidly reduced andthus stable biological removal of phosphorus is possible.

- 135 -

Purpose of MBR application
MBR is thought to be suited for the following conditions;1) Small footprint
2) Advanced treatment
3) Retrofitting of existing wastewater treatment plants
4) Reuse of treated wastewater
5) Chlorination not used for disinfection
Present state of MBRs for municipal wastewater in Japan
Although the introduction of MBRs has lagged behind compared with other fields ofwastewater management, three MBR plants started operation successively in 2005. The first
MBR, Fukusaki Plant, has been operating for one and a half year without any serious troubles.
The in-line chemical membrane washing was not necessary for the first year.
The operating MBR plants for municipal wastewater treatment as well as MBR plants underconstruction are shown in Table 1. In addition, there are several MBR plants for municipal
wastewater currently in the design or planning stage. The number of MBRs for municipal
wastewater is expected to increase in the years ahead.
㪫㫆㫋㪸㫃㩷㪻㪼㫊㫀㪾㫅㪚㪸㫇㪸㪺㫀㫋㫐㩷㪽㫆㫉㪤㪼㫄㪹㫉㪸㫅㪼㩷㪫㫐㫇㪼 㪪㫋㪸㫉㫋㩷㫆㪽㩷㫆㫇㪼㫉㪸㫋㫀㫆㫅㪊㪺㪸㫇㪸㪺㫀㫋㫐㩷㩿㫄 㪆㪻㪀 㫀㫅㫊㫋㪸㫃㫃㪸㫋㫀㫆㫅㩷㩷㩿㫄㪊㪆㪻㪀㪝㫌㫂㫌㫊㪸㫂㫀
㪈㪉㪃㪌㪇㪇
㪉㪃㪈㪇㪇㪝㫃㪸㫋㩷㫊㪿㪼㪼㫋㪠㫅㩷㫆㫇㪼㫉㪸㫋㫀㫆㫅㪢㫆㪹㫌㪿㪸㫉㪸
㪉㪋㪇㪉㪋㪇㪝㫃㪸㫋㩷㫊㪿㪼㪼㫋㪠㫅㩷㫆㫇㪼㫉㪸㫋㫀㫆㫅㪰㫌㫊㫌㪿㪸㫉㪸
㪎㪉㪇㪊㪍㪇㪝㫃㪸㫋㩷㫊㪿㪼㪼㫋㪠㫅㩷㫆㫇㪼㫉㪸㫋㫀㫆㫅㪦㫂㫌㫋㫊㫌
㪌㪏㪇㪌㪏㪇 㪟㫆㫃㫃㫆㫎㩷㪽㫀㪹㪼㫉㪠㫅㩷㫆㫇㪼㫉㪸㫋㫀㫆㫅
㪛㪸㫀㫋㫆
㪉㪃㪇㪇㪇
㪈㪃㪇㪇㪇
㪝㫃㪸㫋㩷㫊㪿㪼㪼㫋㪪㪼㫇㫋㪼㫄㪹㪼㫉㩷㪉㪇㪇㪍㪢㪸㫀㪼㫋㫊㫌
㪉㪊㪇㪉㪊㪇 㪟㫆㫃㫃㫆㫎㩷㪽㫀㪹㪼㫉㪘㫇㫉㫀㫃㩷㪉㪇㪇㪎㪱㫐㫆㫊㪸㫀㪈㪃㪊㪎㪌㪈㪅㪊㪎㪌㪬㫅㪻㪼㪺㫀㪻㪼㪻㪤㪸㫉㪺㪿㩷㪉㪇㪇㪏
㪟㪼㫋㪸
㪊㪃㪉㪇㪇
㪉㪃㪈㪋㪇
㪬㫅㪻㪼㪺㫀㪻㪼㪻㪤㪸㫉㪺㪿㩷㪉㪇㪇㪏
㪦㫆㪻㪸
㪏㪃㪍㪇㪇
㪈㪃㪇㪎㪌
㪬㫅㪻㪼㪺㫀㪻㪼㪻㪤㪸㫉㪺㪿㩷㪉㪇㪇㪐㪥㫆㫋㫀㪺㪼㪑㩷㪈㪃㪇㪇㪇㫄㪊㪆㪻㩷㫉㫆㫌㪾㪿㫃㫐㩷㪺㫆㫉㫉㪼㫊㫇㫆㫅㪻㫊㩷㫋㫆㩷㪊㪃㪇㪇㪇㪧㪜㪥㪸㫄㪼㩷㫆㪽㩷㫋㪿㪼㩷㫇㫃㪸㫅㫋

Table 1㧦MBRs in operation and under constr uction or in the planning stage
The possibilities of MBR and the related researches of JSWA
Risk reduction of the water environment
It is known that a high degree of virus removal could be achieved by MBR. [2]Accordingto previous research by the authors, it was found that Colipharges and Norovirus ofapproximately one-tenth membrane pore size were almost completely removed by a MF
membrane. It was also found that most of the virus existed in the activated sludge, indicatingthat they attached themselves to the activated sludge. [3] It is suggested that the virus
captured in the gel layer that forms on the surface of the membrane also contributes to virus- 136 -

removal. [4] Therefore it is considered that virus removal is influenced by the chemical
washing of the membrane.
The behavior of Norovirus captured in the MBR activated sludge and the influence of thechemical cleaning of the membrane was investigated using a pilot scale MBR which treats 48
m3/d of actual municipal wastewater.

A hollow fiber MF membrane unit with 0.4µm poresize was immersed in the oxic tank and operated at a permeate flux of 0.8 m3/m2/d.
The pilot plant was operated with a HRT of 6 hrs in Run-1, in which the oxic tank HRT was 3
hrs. During the experiment however, in order to evaluate the effect of the HRT on virus
removal, the total HRT was then extended to 18 hrs in which the oxic tank HRT was 6 hrs in
Run-2 and 18 hrs in Run-3 respectively.
The number of Norovirus in the activated sludge decreased with prolonged oxic tank HRT,
and the number of GΣtype in Run ±2 was about 1/1000 that of Run-1 as shown in Table 2.

㪦㫏㫀㪺㩷㫋㪸㫅㫂㩷㫋㪸㫅㫂㩷㪟㪩㪫㩿㪿㫉㫊㪀㪞㪼㫅㫆㫄㪼㩷㫋㫐㫇㪼㪠㫅㪽㫃㫌㪼㫅㫋
㪘㪼㫉㫆㪹㫀㪺㩷㫋㪸㫅㫂㩷㫊㫃㫌㪻㪾㪼㪜㪽㪽㫃㫌㪼㫅㫋

㪩㫌㫅㪄㪈
㪊

㪩㫌㫅㪄㪉
㪍

㪩㫌㫅㪄㪊
㪈㪏

㪞㸇
㪞㸈
㪞㸇
㪞㸈
㪞㸇
㪞㸈
㪋㪅㪉㪇㪜㪂㪇㪎 㪊㪅㪌㪇㪜㪂㪇㪏 㪉㪅㪌㪇㪜㪂㪇㪎 㪈㪅㪐㪇㪜㪂㪇㪏 㪉㪅㪌㪇㪜㪂㪇㪎 㪈㪅㪐㪇㪜㪂㪇㪏㪈㪅㪈㪇㪜㪂㪇㪏 㪍㪅㪉㪇㪜㪂㪇㪎 㪈㪅㪌㪇㪜㪂㪇㪍㪥㪅㪛㪅㪉㪅㪎㪇㪜㪂㪇㪌
㪥㪅㪛㪅
㪥㪅㪛㪅
㪥㪅㪛㪅
㪥㪅㪛㪅
㪥㪅㪛㪅
㪥㪅㪛㪅
㪥㪅㪛㪅
㩿㪚㫆㫇㫀㪼㫊㪆㪣㪀

Table 2: Norovirus measurement r esults for different aerobic tank HRT
This indicates that the aerobic decomposition of the virus, which was adsorbed in theactivated sludge and retained in the oxic tank, will progress with the elapse of time.
The number of Norovirus was measured at 30, 60, and 120 minutes after the in-line chemical
membrane washing using a 0.3% NaOCl solution. No Norovirus were detected in the MBR
effluent after the completion of chemical washing procedure. This may suggest that the roleof gel layer of the membrane surface on virus removal is less important than the adsorption
effect of the activated sludge.
Reduction of excess sludge production
It is reported that excess sludge production can be reduced in MBR compared to otheractivated sludge processes. [5] An experiment using two 200L bench scale MBR plant was
conducted to investigate the aerobic digestion function of MBR. The HRT of both bench scale
plants were 18 hrs. One plant (Plant A) was operated with anoxic tank HRT of 9hrs, while theother plant (Plant B) was operated only under oxic conditions.
Both plants were fed with actual municipal wastewater and were operated continuously for
four months without excess sludge withdrawal. Since the experiment was conducted during
the winter season, the bench scale plants were heated to maintain the water temperature at30͠ for the latter part of the experiment. Before the installation of the heater, the watertemperature of the bench scale plants was around 15͠.

- 137 -

Plant A showed constantly higher TMP (Trans Membrane Pressure) than Plant B andchemical membrane cleaning was necessary in the last part of the experiment term. On theother hand, TMP of Plant B remained stably low. Excess sludge production rate wascalculated based on the phosphorus balance of the process. The sludge production rates basedon SS were 0.6-0.7 gSS/gSSin before the installation of the heater. After the installation of theheater, the sludge production rate decreased to 0.3-0.35 gSS/gSSin for both plants. In order toobtain consistency in the excess sludge reduction effect by MBR, measures to prevent heatloss of the MBR reactor during the winter season are required.
Odor emission of MBR
It is expected that MBR emits less odors compared with other activated sludge processes,
since MBR has no primary settling tank and sludge is well stabilized under long SRT
operations. The results of measurements of main odor components of MBR are shown in
Table-3. In the table, the data of other activated sludge processes and primary settling tanks
are also shown. Most of the odor component concentrations in the oxic tank exhaust gas of
the MBR were lower than those of the CAS (Conventional Activated Sludge) process and theOD (Oxidation Ditch) process except dimethylsulfide. However, the odor component
concentration of the air of anoxic tank headspace was higher than those of CAS and OD
aeration tanks. It indicates that odor components will be generated under anoxic conditions.
From the viewpoint of odor emission prevention, it is recommended to cover the anoxic tanks
and ideally keep the headspace in a negatively pressurized condition.
The fine screen is also where odor may be being emitted. It is recommended that theequipment be contained in a building or covering.
㪧㫉㫆㪺㪼㫊㫊
㪘㫄㫄㫅㫆㫅㫀㪸 㪟㫐㪻㫉㫆㪾㪼㫅㫊㫌㫃㪽㫀㪻㪼 㪛㫀㫄㪼㫋㪿㫐㫃㫊㫌㫃㪽㫀㪻㪼 㪤㪼㫋㪿㫐㫃㫄㪼㫉㪺㪸㫇㫋㪸㫅 㪛㫀㫄㪼㫋㪿㫐㫃㪻㫀㫊㫌㫃㪽㫀㪻㪼㪤㪙㪩㩷㪸㫅㫆㫏㫀㪺㩷㫋㪸㫅㫂
㪇㪅㪇㪏
㪇㪅㪇㪎㪋
㪇㪅㪇㪈㪏
㪇㪅㪇㪐㪊
㪇㪅㪇㪇㪉
㪤㪙㪩㩷㫆㫏㫀㪺㩷㫋㪸㫅㫂㪇㪅㪇㪐㪇㪅㪇㪇㪇㪐
㪇㪅㪇㪇㪈㪌
㪥㪅㪛㪅
㪥㪅㪛㪅
㪚㪘㪪
㪇㪅㪇㪐
㪇㪅㪇㪇㪊㪎
㪇㪅㪇㪇㪊㪌
㪇㪅㪇㪇㪉㪐
㪇㪅㪇㪇㪈㪌
㪦㪛㵪㪇㪅㪇㪇㪉㪉
㪇㪅㪇㪇㪇㪉
㪇㪅㪇㪇㪇㪊
㪇㪅㪇㪇㪇㪈
㪧㫉㫀㫄㪸㫉㫐㩷㫊㪼㫋㫋㫃㫀㫅㪾㩷㫋㪸㫅㫂
㪇㪅㪊㪌
㪇㪅㪌㪐
㪇㪅㪇㪊㪎
㪇㪅㪇㪍㪌
㪇㪅㪇㪇㪌
㩿㫇㫇㫄㪀

Table 3: Results of odor measurement of MBR and other process
Application to BNR process
Figure 2 shows a new biological nutrient removal (BNR) process for large facilities. withmembrane separation.[6] This process combines the step feed multi-stage
nitrification-denitrification process, which is a popular BNR process in Japan, and membrane
separation. In a single-stage MBR as shown in Figure 1, in order to obtain nitrogen removal
efficiency of more than 80%, circulation ratio of some 400% (R=4) is necessary.

- 138 -

㪤㪼㫋㪿㪸㫅㫆㫃㪜㪽㪽㫃㫌㪼㫅㫋

㪜㫈㫌㪸㫃㫀㫑㫀㫅㪾㩷㪫㪸㫅㫂㪘 㪦 㪘 㪦 㪘

㪦

㪤

㪧㪛㪥

㪘㪑㩷㪸㫅㫆㫏㫀㪺㩷㫋㪸㫅㫂㪦㪑㩷㫆㫏㫀㪺㩷㫋㪸㫅㫂㪧㪛㪥㪑㩷㫇㫆㫊㫋㪄㪻㪼㫅㫀㫋㫉㫀㪽㫀㪺㪸㫋㫀㫆㫅㩷㫋㪸㫅㫂㪤㪑㩷㫄㪼㫄㪹㫉㪸㫅㪼

Figur e 2 㧦Flow of the BNR process with membrane
However, in the membrane BNR process shown in Figure 2, a T-N removal efficiency of
about 80% is acquired at a circulation ratio of 200%. The experiment results showed thatstable nitrification and denitrification could be achieved even in low water temperature period.
Good and stable biological phosphorus removal can be achieved if the first anoxic tank acts as
an anaerobic tank. This is enabled by adding methanol to the post-denitrification tank andeliminating NOx-N in the returned mixed liquor.
Perspective of the future development of MBR
The MBR will not remain just one of many wastewater treatment technologies, but is
expected to become a core technology that will be used for various types of wastewater
management. Figure 3 shows the possible deployment of MBR.
In Japan, MBR is expected to be increasingly used for municipal wastewater treatment.
Although the MBR has been used mainly for small scale plants so far, it will likely be applied
to larger plants in the future.
㪪㫄㪸㫃㫃㪄㫊㪺㪸㫃㪼㩷㫇㫃㪸㫅㫋㫊㪘㪻㫍㪸㫅㪺㪼㪻㩷㫋㫉㪼㪸㫋㫄㪼㫅㫋㪩㫀㫊㫂㩷㫉㪼㪻㫌㪺㫋㫀㫆㫅㪪㫆㫃㫀㪻㫊㩷㫉㪼㪻㫌㪺㫋㫀㫆㫅㪤㪙㪩㪩㪼㫌㫊㪼㩷㫆㪽㩷㪼㪽㪽㫃㫌㪼㫅㫋㪞㫉㪸㪻㪼㩷㫌㫇

㪩㪼㫋㫉㫆㪽㫀㫋㫋㫀㫅㪾㪣㪸㫉㪾㪼㪄㫊㪺㪸㫃㪼㩷㫇㫃㪸㫅㫋㫊

Figur e 3 㧦The possible deployment of MBR- 139 -

To enable the wider use of MBR for various purposes, the following issues are considered tobe essential.
1) Optimization of the design method.
2) Optimization of the maintenance method, especially fouling control and chemicalcleaning of membrane.
3) Reduction of membrane cost and prolongation of membrane life.
4) Reduction of energy consumption, especially air supply for membrane cleaning.
JSWA will continue technology development of MBR in cooperation with universities andprivate enterprises and will conduct the second technical evaluation of MBR based on the dataobtained from the four operating actual MBR plants in the near future.
Summary
MBR is gaining a firm position in the wastewater treatment technologies and it offers various
possibilities for wastewater management. However, there are still problems to be solved forthe wider spread of MBR. The technical cooperation and information exchange with German
engineers will greatly contribute to the technology development of MBR.
References[1] Technical Evaluation Committee of Japan Sewage Works Agency, ³Report of Technical
Evaluation of MBRs´(In Japanese), November 2003
[2] Ottoson,J., Hansen,A., Bjorlenius,B., et al, ³Removal of Viruses, Parasitic Protozoa andMicrobial Indicators in Conventional and Membrane Processes in a Wastewter Pilot Plant´
Water Research 40 (2006) 1449-1457[3] Oota,S., Murakami, T.,Takemura, K. and Noto, K. ³Evaluation of MBR Effluent
Characteristics for Reuse Purposes´ Water Science & Technology Vol. 51 No6-7 pp441-446,
2005[4] Ueda,T.,Horan,N.j.,´Fate of Indigenous Bacteriophage in a Membrane Bioreactor´
Water Research 34 (2000) 2151-2159[5] Oota,S., Murakami, T., ³Reduction of Excess Sludge Production by Intermittent Feed
MBR´, Proceeding of IWA Asia-Pacific Regional Conference ³Asian Waterqual 2003´(CD-ROM), October 2003
[6] Oota,S., Murakami, T., and Uriu, M. ³Advanced BNR Process Combined with Membrane
Separation´, Proceeding of IWA Asia-Pacific Regional Conference ³Aspire 2005´ (CD-ROM),
July 2005- 140 -

- 141 -• “Technical evaluation of MBR “(2003)
Process configuration
Operation & maintenance
Performance
Conditions of MBR application
Costs
etc.
• “The temporary design guideline “(2003)• Five MBRs are in operation (2006)

Outputs of JSWA Researches
on MBR

3

1

R&D Dept., Japan Sewage Works Agency

Takao Murakami

Japanese Experience of MBR
Application to Municipal Wastewater
Treatment

2

4• Most of sewer systems are separate system.
• The strength of raw wastewater is weak.
• Household wastewater occupies the mostpart in the middle and small-scale sewer.
• Considerable amount of infiltration in rainy
weather.
• High flow fluctuation in small-scale sewer.

Characteristics of Japanese Municipal
Sewer System

R&D

Technical assistanceTraining of local municipality staff

Planning/Design/Construction of WTPs

• Public organization established by theGovernment and local municipalities• Purpose: Support local municipalities insewage works• Activities

Introduction of JSWA- 142 -Equalization
Tank

1mm screen

BlowerExcess sludge

Diffuser

Membrane

Flow equalization

Mixer

AnoxicTank

Coagulant

Chemical for
Backwash75Effluent

Chemical washtank

• 4.5hrs of HRT for small-scale plants• Functions as a settling tank bypassing
bioreactor in emergency

Inflow

Basic Flow of MBR• HRT 3hrs for anoxic tank, 3hrs for oxictank
• Possibility of the tank volume reduction

Bioreactor• 2-3 mm bar screen for FS• 1mm or 0.5 mm drum screen for HF• Equipped with automatic dewatering
devicePretreatment

86

- 143 -HF Membrane module

Membrane modules (FS)11

9

Activated sludge

Feed Channel∅ 2.5 mm

Filtrate

Filtrate collecting
channel12

Filtrate slits

Ceramic monolith membrane module

10

FS Membrane module for large-scale
application

- 144 -Magnify

13

Name of the plant

15

Total design
Capacity for
Membrane Type Start of operation
capacity (m3/d) installation (m3/d)
Fukusaki
12,5002,100
Flat sheet
In operation
Kobuhara
240
240
Flat sheet
In operation
Yusuhara
720
360
Flat sheet
In operation
Okutsu580
580 Hollow fiber
In operation
Daito
2,000
1,000
Flat sheet
In operation
Kaietsu230
230 Hollow fiber
April 2007
Zyosai
1,375
1.375
Undecided
March 2008
Heta
3,200
2,140
Undecided
March 2008
Ooda
8,600
1,075
Undecided
March 20093
Notice: 1,000m /d roughly corresponds to 3,000PE

MBRs in operation or under construction

Magnify• Small footprint• Advanced treatment (C,N,P)• Reuse of effluent• Retrofitting• Grade up of treatment• Avoid chrolination in disinfection

Purposes of MBR application

16

14

Present state of MBRs application
for municipal wastewater

- 145 -Furumine Shrine

33240m /d（９０m /d）

Kobuhara Plant

Started operation from the end of March, 2005
Capacity 2,100m3/d (Planned Capacity 12,500m3/d)

19

17

The first MBR for municipal wastewater in Japan

Fukusaki Plant

3

360m /d20

18

Fine bubble diffuser

Yusuhara Plant

Membrane unit

- 146 -

3580m /dIntroduction of JSWA
researches on MBR

Okutsu Plant

21

Reuse of effluent

Risk reduction

Advenced treatment

Large-scale plants

MBR

Small-scale plants

22

Retofitting

24

Grade up

Solids reduction

MBR as a core technology

3230m /dKaietsu Plant

- 147 -Capacity (m3/d)
MLSS (g/L)
Membrane module
Material
Pore size (μm)
Flux (L/m2/hr)
TMP (kPa)

48
8-10
HF
PVDF
0.4
33
<30

Pilot plant

Risk reduction of the water
environment

27

Run-1
Run-2
Run-3

Total HRT (hrs) Oxic HRT (hrs)
6
3
18
6
18
18

Experimental condition

Φ２５～３５ｎｍ

Very small in the size
Tolerant toward chlorine disinfection

28

26

Main cause of food poisoning, especially oyster

Norovirus

- 148 -

Run-2
6

Run-3
18

29

(Copies/L)

GⅠ
GⅡ
GⅠ
GⅡ
GⅠ
GⅡ
4.20E+07 3.50E+08 2.50E+07 1.90E+08 2.50E+07 1.90E+08
1.10E+08 6.20E+07 1.50E+06
N.D.
2.70E+05
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.

Run-1
3

Elapsed time ａｆｔｅｒ
chemical cleaning
30min
60min
120min
GⅠ
N.D.
N.D.
N.D.

GⅡ
N.D.
N.D.
N.D.
(Copies/L)

Norovirus type

31

Influence of in-line chemical cleaning

Oxic tank tank HRT(hrs)
Genome type
Influent
Aerobic tank sludge
Effluent

Results of Norovirus mesurement• High removal efficiency by MF MBR• Adsorption of virus to sludge flocks is
the reason of removal• Gel layer on the membrane surface is
not important for virus removal

Summery of Norovirus removal

Φ２５～３５ｎｍ

Attached to flocks → Rejection by membrane

Attached to solids

Supernatant

Location of Norovirus

32

30

- 149 -

0.2
0.1
0

0.6
0.5
0.4
0.3

0.9
0.8
0.7

0

10

20

30
40
SRT (days)

800
50

1000
60

Sludge production and SRT

70

35

Sludge reduction by extended
HRT operation

Sludge production rate (gSS/gSS)

Odor emission of MBR• 200L Bench scale MBR with HRT 18hrs
A : anoxic 9hrs, oxic 9hrs
B : oxic 18hrs• No big differences between A and B in
sludge production• Small sludge reduction effect at low
temperature• Sludge production depends on process
SRT
34

- 150 -Equalizing Tank

HRT 10hrs, T-Neff≦5mg/l

A O A

O
A

PDN

Effluent

A: anoxic tank
O: oxic tank
PDN: post-denitrification tank
M: membrane

O M

Methanol

39

Application of Membrane to Large-scale BNR Process

37

Process
Ammnonia Hydrogensulfide Dimethylsulfide Methylmercaptan Dimethyldisulfide
MBR anoxic tank
0.08
0.074
0.018
0.093
0.002
MBR oxic tank
0.09
0.00090.0015
N.D.
N.D.
CAS
0.09
0.00370.00350.00290.0015OD―
0.00220.00020.00030.0001Primary settling tank
0.35
0.59
0.037
0.065
0.005
(ppm)

Results of odor measurement

Cumulative frequency (%)

20

40

60

80

100

0

ＫＪ－Ｎ

6

8

ＮＯ３－Ｎ

Effluent Ｔ－Ｎ，Ｋｊ-Ｎ，ＮＯ -Ｎ ｍｇ/Ｌ

2

Ｔ－Ｎ

Nitrogen removal

BNR process withmembrane separation

1040

- 151 -N,P(mg/l)

5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0

A1

O2

A2

O2

A3

O3(M)

Profiles in each tank

PDN

NH4-N
NO3-N
PO4-P

43

41

• Opimization of the design method• Optimization of the maintenancemethods, especially fouling control andchemical cleaning of membrane• Reduction of membrane cost andprolongation of membrane life
• Reduction of energy consumption,
especially supply air for membranecleaning
are essential
MBR:0.8kWh/m3, OD:0.6-0.7kWH/m3

For the wider use of MBR;

44

42

- 152 -45

Flash toilet
Sprinkle water• Reuse in large-scalebuildings• Industrial wastewater

ＭＢＲ

47

History of MBR application in Japan

ISA, RWTH Aachen, on Hybrid MBR

Japanese private enterprises (3 + 1 group)

JSWA starts joint research for large-scale
application of MBR with;

From Hitachi-zosen HP• Night soil treatment• Small-scale on-site treatment

From Kubota HP

48

46

Vielen Dank für Ihre Aufmerksamkeit

Control- and Information System
for wastewater pumping and distribution
in Berlin(LISA = Leit- und Informationssystem Abwasser)

Berliner Wasserbetriebe (BWB)
Division sewage-works
Cicerostraße 24
10709 Berlin- 153 -

Table of contents

1.

History

3

2.

Sewage-system of the BWB before LISA

4

2.1

System and operations

4

2.2

Existing operations-optimum

5

Central control of the sewage-system

6

3.1

Operations-concept

6

3.2

Advantages

7

3.

2

- 154 -

1.

History

The service and supervision of the Berlin wastewater pumping system has experienced
diverse changes in the last 40 years.
Since the 1960´s, a pumping-station-renewal-program was implemented in the westernpart of the city, that intended to automate 55 pumping stations until then operated
mainly by hand and to concentrate the control and operations in main pumping stations.
With the start of operations of the renewed pumping stations Bln IX in 1998 andWilmersdorf in 1999 the completion of the program and with it the concentration onseven main pumping stations occupied by personnel (Zhl, Stg, Chb, Wil, Spa, Wit andKrb) was reached.
The high stand of the automation-technology (programmable logic controller) as well as
the control- and supervision-technology (LSX) allowed for a continuously personnelminimization in the operation of the pumping stations, which was realized in 1996 with
the introduction of the new operation- and personnel-structure in the western part of thecity.
Parallel to this the wastewater pumping system as it was applied in the western part ofthe city was introduced also in the eastern part of the city after the consolidation of the
VEB WAB Berlin with the BWB. The pumping stations of the eastern part were in extremely bad structural and technical conditions and were operated also mainly by hand.
Differently to the western part of the city only a few pumping stations were fully renewed
and the operation concept changed to inflow operation with deep set intakes and pumps
with little astringencies.
In order to reduce nevertheless the high costs for personnel a number of pumping stations (e.g. Ros, Buh, Fhg, Hdf, Kht I) have been automated and equipped with telecontrol using the existing buildings and pumps, knowing that this would mean a higher rateof faults and failures.
In the eastern part of the city six main pumping stations with their associated pumping
stations (Bri, Köp, Lbg, Mit, Mar and Pan) were formed. The mounting of the controland supervision-technology into the main pumping stations was finished with the realisation of the main pumping station Mitte (completion 2000). This included the supervision and telecontrolling of the affiliated automatically working pumping stations. Analogously to the western part of the city a new operations- and personnel-structure wasintroduced in the eastern part by 01.04.01, which led to a reduction of workplaces.
Seven pumping stations (Bln IV, XI, XII, Grü, Joh at, Hgt, Hsch) were left for operationby hand until the renewal, still equipped with old pumping systems.
The age-structure of the employees in connection with early retirement plans and partial
retirement led to the problem that necessary positions could not be reoccupied with regard to the remaining staff. Unforeseen departures still reinforced this problem.

3- 155 -

2.

Sewage-system of the BWB before LISAThe operation of the sewage-system was as follows:
Under Äsewage-system ³the entire system for the sewage disposal is understood. It includes the following components:

Sewage-system =2.1

Sewer-network incl. storm water tanks
Wastewater pumping stations
Pressure mains system
Wastewater treatment plants
Discharge system of wastewater treatment plants

System and operations

The present operations and the current plans can be described as follows: Sewer-network
A management of the sewer-network doesn't take place normally for lack of available
controls that can be operated. In addition to the existing weir Seestraße it is planned
however to build more control-appliances.
Because of the lacking sewer management, the sewer-maintenance can be enforced
largely independently of the operation of pumping stations, sewer mains network or
wastewater treatment plants.
Controls of storm water tanks, mainly for emptying and cleaning, are realized by thepumping station personnel.
 Wastewater pumping stations and pressure mains system
Basis of the sewage-distribution through the pumping stations are the controllable,maximum sewage-streams, which are following the demands of the wastewater treatment plants regarding the technical conditions and the treatment limits. For eachwastewater treatment plant exists a so called ³coordinating main pumping station´,
which ensures the wastewater streams for the treatment plant by close adjustment
with the other main pumping stations and the possibilities of the pressure mains system.
The fulfilling of the wastewater treatment plant demands is largely guaranteed by thefact, that many pumping stations are able to reach several destinations using different pressure mains.
The control of the pumps, that means turn on and turn off of the pumps as well as adjusting the flow of the bigger pumps where possible through speed-control, takes
place essentially only as Älong-distance-hand-control³ from the responsible main
pumping station, provided an intervention is necessary into the normally leveldependent automatic control.
For control and supervision are all pumping stations assigned to one of the 13 main
pumping stations run by personnel.
4- 156 -

In addition data are made available also for the coordinating main pumping stations,so that these can fulfil their tasks of wastewater delivery to the wastewater treatment
plants. A comprehensive central control does not take place here, with exception of
the assigned pumping stations.
Some pumping stations, seven before the beginning of LISA, could be operated only
by hand in the station and were therefore, as already mentioned, still occupied.
The redistribution of the wastewater-streams partially takes place through valvechanges initialized by the personnel of the main pumping station, partially howeveralso through personnel of the pressure mains system on the spot in the streets.
To the operation-tasks belong beside the control and supervision (operation) also following tasks:- Inspection of the installations- Recording of operation data, which are not yet transferred to the main pumping
station- Fault-elimination in the continuous shift work
- Cleaning of the suction-areas- Maintenance-tasks that are closely connected with pumping- Preparation of material- Inducement of maintenance of the equipment
For this, altogether 544 employees including running of the pressure mains systemand personnel of the headquarters were necessary after the alteration of the structure of the subdivision had taken place.
 Wastewater treatment plants
Concerning the treatment of wastewater, the wastewater treatment plants are operated independently of each other in accordance with the inflowing wastewater. The
operations are supported by automation-technology and control-systems, which are
differently in the plants.
- Discharge system of wastewater treatment plants
Control-systems in the discharge system are normally not in the responsibility of the
BWB, so that the operational activities include mainly the controls of the perfect condition of the discharge system.
2.2

Existing operations-optimum

With the existing applied information- and control-strategy in the sewage-system could
be reached the following:x

Sewage-distribution in accordance with the flow with restricted possibility of consideration of the current cleaning-capacity of the wastewater treatment plants.

x

Optimization of the operation efficiency of the single wastewater treatment plant andthe single main pumping station group.

5- 157 -

x

3.

Observance of the critical values, especially of the wastewater quality, and optimization of the technical operation of the single wastewater treatment plant.

Central control of the sewage-system

A system that further minimizes the expenditure for operation, control and supervision
through automation must be found, in view of the decreasing financial resources.
In the past mainly the different, historically grown automation-systems prevented awide-range automation of the sewage-system. With the nowadays available systems
including the possibility of creating networks it became significantly easier to realize
such a project.
3.1

Operations-concept

The central control of the sewage-system means that the operational processes of thesystem are observed, supervised and operated by personnel in a central control room.
With a complex system as given, this can only be achieved for sure by using a processcontrol system, which communicates with the decentralized automation units. Then,
presumably such a system is installed; the tasks of the central control room consist essentially of the input of setpoint values for the central or local automation system, theinput of control settings and the handling of failure or disruption information.
Because of the complexity of the pumping system as well as the necessity to control
hundreds of measuring points (e.g. levels, flows, pressure) simultaneously it is not possible to gain synergy effects only by centralisation of controlling and supervising. Furthermore the changing requirements for the system due to reconstruction or damages ofmains, maintenance of the sewers or only weather conditions are a challenge for thecentral system. Therefore new process control schemes and functionalities of the control system for the general survey must be developed using only a limited number ofmonitors.
An integral approach of the sewage-system and the following premises form the basicsof the drafted operational concept:
x The control of the sewage-system takes place comprehensively regarding thetreatment-capacities of the various wastewater treatment plants.
x The central control remains limited at first to the sewer and pumping system.
The supervision and control of the sewage drainage and pumping system takes place ina central control room. This way the operational dependences of the single operationareas can be taken into account. The technical and operational structure of this central
control room depends on the available technical possibilities at present.
For the environmentally sound and economical operation of the entire sewage-system
the information of the current treatment capacities has to be available also. Within thecomplete wastewater system the treatment plants are viewed as almost independent
plants however and, like now, will be controlled by means of a local automation system.

6- 158 -

Following principles exist regarding the control of the sewage-system:
x Superior control- and operation tasks for management of the sewage-system are
executed without exception only in the central control room. The reason for this isthat all important data for the management of the sewage-system are available for
evaluation and assessment.
x Local automation-tasks are executed decentralized. This is absolutely necessary fortime or security-relevant processes. To the conditions of the outstations adapted, decentralized automation systems must be therefore present.
x Remote plant control by the central control room of the local automation system of awastewater treatment plant is to be ruled out.
x The availability of the control- and automation-system must be defined; it is to beviewed in context with the personnel-allocation.
x For the handling of the control-tasks suitable displays must be created for the pumping procedures, which minimize the previous diverse actions, relieve and shorten thedecision making, so that personnel-reduction is possible.
x Changes of the pressure mains, which are necessary for a save sewage-disposal, pumping and ±distribution should become telecontrolled from the central control
room also.
Another important task of the central control system is the qualified treatment of malfunctions with a ranked alarm-concept respecting the single installations and the central
control room. The fault clearing groups and maintenance workers are working in the
single installation of any given pumping station directly. Accordingly, elaborate information of the current conditions of the single installation must be available or accessible on
the spot.
Advisably the personnel of the central control room prepare the information for reporting,documentation, archiving as well as administration and accounting of the sewagesystem altogether also. In addition the exchange of information with the supervising authority may be necessary. The availability of current weather-data (precipitation-heights,
weather-radar-pictures) on the other hand admits improved prognoses respecting theforthcoming sewage-flows and enables interventions in the sewer- and pressurenetwork in advance, especially with locally restricted precipitation-events.
Because of the complexity of the sewage-system, the staff should be supported in his
decisions for the sewage-distribution by a model-supported prognosis-system, on the
one hand in a technical sense, but on the other hand also concerning the economical
operation of the system. This model-supported prognosis-system should only be realized in the second step, however.
3.2

Advantages

After the implementation of this program, the following advantages are anticipated:x

The sewage discharge and wastewater pumping can be operated in an economical
optimum.
7- 159 -

x

Savings regarding energy-use are to be expected.

x

Decrease of mixed sewage outlets of the sewer system into surface-waters throughcomprehensive control of the sewage-system and optimal utilization of the existing
capacities as well as through extensive and readily available data like e.g. radarweather-pictures and levels in the sewer-network.

x

Diminution of the investment-expenses for spare capacities through flexible usage ofplants and refined control-systems.

x

Improvement of the information-preparation.

x

Essential reduction of the personnel costs.

8- 160 -

- 161 -Wastewater treatment plants(incl. 2 operated by contract)

Force mains network

Pumping stations

Sewer network
80% separated sewerage
20% combined sewerage

1 213 000 m³/d Maximum treatment

652 800 m³/d Average treatment

6

1 109 km147

9 330 km

Wastewater Works

Dr. Carin Sieker
Berliner Wasserbetriebe
09. October 2006

Central managementof Berlin waste waters

Seite 3

RuhlebenHavelkanal

Wansdorf

Stahnsdorf

510 000 inhabitants

Wastewater treatment for

Waßmannsdorf

Schönerlinde

94 000 inhabitants

386

5 210

3 390 000

889 km²

Land Brandenburg
Drinking water supply for

Trainees

Employees at BWB

Inhabitants

Area of the city

For Berlin and Brandenburg:
Berliner Wasserbetriebe

Seite 4

Münchehofe

Seite 2

- 162 Stormwater tanks

1109 km Pressure mains
22

147

Wastewater Pumping System

Pumping stations

bathing water

Seite 7

Seite 5bank filtration (water supply)

Berlins

Bathing Water and Bank Filtration Areas

Wansdorf

Stahnsdorf

Ruhleben< 10 m3/s

Inflow Brandenburg:

2,3

0,5

Münchehofe

Distribution ofWastewater

Waßmannsdorf

Schönerlinde

7,2 m3/s

2,6

1,2Treated Wastewater:

0,6

2-3

during dry weather in Summer

Inflow and Emissions [m3/s]

Seite 8

Seite 6

6-7

- 163 Seite 11¾ Reduction of personnel costs¾ Improvement of provision of information¾ Reduction of stormwater overflows¾ Economical use of energy

following components:

Targets

Implementation
Implementation 2002
2002 -- 2008
2008

¾ Total optimum for wastewater system- Control system- Optimisation system- Information system

Seite 10

Seite 12Control and Information System Wastewaterand treatment system in Berlin withfor the operation of the wastewater pumping

Implementation of a control and information system

Board decision 0kt. 2001

Seite 9Control- and Information System for
wastewater pumping and distribution
in Berlin

Leit- und Informationssystem Abwasser

LISA

- 164 -13 executive pumping stations
with on-site personal organised
in shifts

146 pumping stations

Starting point

control

order

Maintenanceone central control roomensuring remote action¾

Seite 15

Repair service

full automationof the 13 exec. stations

Pressure
pipes¾

Pumping
stationCentralcontrolroom

Water authority

upgrading and automationof 44 pumping stations
Criteria: daily dry weather
flow > 6000 m³/d ormax. flow > 100 l/s

SewersRain tanks

BWB-digital-network

realisation

WWTP

information

River,
effluent

Meteorological service

Future control of wastewater system¾

LISA programme

Ongoing Measures
Increasing the Operational Efficiency

the operating engineers. It includes model- New automatic system(water level-flow-control)

Seite 13

An expert system is implemented which supports- Super ordinate and centralised control unit

simulation and forecast-data, e.g. weather forecast.

Components of optimisation

Components of the control system

Seite 16

Seite 14

- 165 -

z

z

z

z

Operation and Control Centre

APw n

z

APw n

HPw 13APw 1z

BWB WANLSX

Archiving and logging(Protokollierung)

APw 1

HPw 1

LISA- workstations

Future process control system

Seite 19

Seite 17

HPW HPW HPW
Lbg
Stg
Zhl

HPW HPW HPW
Chb I Spa I Bln II

Seite 18

Pumping target
Main-WWTP Ruhleben(WWTP Wan)

Regional centre
HPw Chb I

Seite 20

Super ordinate and centralised control unit

HPW HPW HPW
Wil Mar I
Bri

Pumping target
Main-WWTP Waßmannsdorf(WWTP Stdf)

Pumping target
Main-WWTP Schönerlinde(WWTP Mhf)

HPW HPW HPW HPWBln V Köp I Kar
Wit

Regional centre
HPw Wil

Regional
Regional centre
centreHPw Bln V

central control room LISAStructure of the central control room- 166 -• The personal moved in January 2005.

¾ Upgrading / expansion of the measure and control
technics in the wastewater system

23• Operational problems existed with the new pumps withvariable speed drive units (partial load operation)• 12 pumping stations are still in the planning phase.

• Failure of temporary/provisional arranged devices, e.g.
pumps during the reconstruction phase have an immediateinfluence on the discharge situation• Difficulties occurred during the implementation of the newsoftware for the primary control system• New requirements and gained experience often changed the
project contents and working process• The documents and information used for planning differedfrom the on-site situation• Changes in organisation and infrastructure took place during
full operation• 21 pumping stations presently are under reconstruction,• 8 of the former 13 pumping station groups are connected toand controlled by the central control centre,

Since Mai 2006

Project status (2)¾ Hard- and software for the superior
process control system

Problems and challenges• The control centre and the head quarter for theoperation department of the pumping stations andpressure main network were implemented in thebuilding of the main pumping station Bln V,
Holzmarktstraße.

¾ Electrification of shut-off valves in roads(in wastewater force mains network)

Seite 21

• In the central control unit the operational test periodbegan in November 2004.

¾ Reconstruction of machines and electro-technics

in selected adapter and main pumping stations

Project status (1)Measures / Investments

24

22

- 167 -Thank you for your attention.

25

Renovation of secondary treatment facility into the Step-feed Biological Nitrogen
Removal Process by the effective use of the existing structure

Kiyohiko Hayashi
Director, Toba Wastewater Treatment Plant,
Sewerage Department, Water and Sewerage Works Bureau, Kyoto City

Summery:
In order to improve the water environment in Kyoto city and in the down stream ofdischarging rivers, suitable advanced treatment processes have been adopted into
existing facilities by way of renovation. In the case of the existing secondary treatment
facility at Toba treatment plant, the step-feed biological nitrogen removal process waschosen since it can be applied without any large-scale remodeling of the structure of the
facility, and can be maintained easily.

Key Wards:
Advanced treatment, Nitrogen removal, Renovation, Step-feed biological nitrogen removal

1. Sewerage works of Kyoto city
(1) Outline
Kyoto city, which has more than 1200 years of history, is located in the midstream of
the Yodo River from Lake Biwa to Osaka Bay. The population of the city is around 1.47
million. Almost all of the water required is obtained from Lake Biwa through water
channels and all treated effluent from wastewater treatment plants is discharged to
the Yodo river water system. As the Yodo River water is used for drinking water bymore than 11 million people in Osaka and other cities, the sewerage system has asignificant role and its construction has been pursued vigorously. The sewered
population ratio as of 2006 is 99.1%. And the sewerage system has contributed to
improve the water quality of the Yodo River water system including rivers in the city.
However, as further strict design standards concerning BOD, COD, nitrogen andphosphorus will be established for each wastewater treatment plant, additional
improvement of effluent quality will be required.
(2) Promotion of Advanced Treatment
Considering of the location of the city, not only nitrogen and phosphorus but color are
fixed for the objective constituents of the advanced treatment in order to improve theappearance of river water. Biological removal processes have been applied for nitrogenand phosphorus while ozonation has been applied for color removal.
- 169 -

Because immense construction costs are required for introducing advanced
treatment, simultaneous removal processes for nitrogen and phosphorus are applied incase of renovation of the whole structure, and removal processes for one of theconstituents is applied in case of renovation of equipment such as diffusers in reaction
tanks. As compared with conventional activated sludge systems, biological advanced
treatment processes require longer reaction time, so facility volumeter of the advanced
treatment generally has to increase. But in Kyoto city, influent volume has been
decreasing after a volumetric peak in the early 90s on account of elevation of watersaving consciousness, and moving colleges and factories out of the city as well as alingering recession. Therefore, advanced treatment has been adopted by according as
the decrease of influent volume without any expansion of the facility volumeter.
(3) Outline of Toba Wastewater Treatment Plant
The first treatment line of the Toba plant, which is the 9th oldest one in Japan, began
operating in 1939. The amount of influent wastewater into the plant is about 63% of
the wastewater generated in the city. The present treatment capacity is 975,000m3/day.
As shown in Table-1, there are eleven treatment lines from A to K in the plant. Those
treatment lines had been constructed year by year, and conversion works of those lines
from conventional activated sludge process into advanced treatment has beenpromoted stepwise. A-line was converted into the anaerobic-anoxic-oxic (A2O) process
for the nitrogen and phosphorus removal on the occasion of the renovation of whole
structure. E and F lines were converted into the anaerobic-oxic (AO) process for thephosphorus removal by way of renovation of diffusers in the reaction tank.
Table-1 Treatment capacity of each line in Toba Plant㪫㪩㪜㪘㪫㪤㪜㪥㪫㩷㪣㪠㪥㪜㩷

㪘㩷

㪙㩷

㪚㩷

㪛㩷

㪜㩷

㪝㩷

㪞㩷

㪟㩷

㪠㩷

㪡㩷

㪢㩷

㪫㪦㪫㪘㪣㩷

㪚㪦㪤㪤㪜㪥㪚㪜㪛㩷㪦㪧㪜㪩㪘㪫㪠㪦㪥㩷

㩾㪐㪎㩷

㩾㪍㪋㩷

㩾㪍㪍㩷

㩾㪍㪎㩷

㩾㪍㪐㩷

㩾㪎㪈㩷

㩾㪎㪊㩷

㩾㪎㪍㩷

㩾㪎㪐㩷

㩾㪏㪋㩷

㩾㪏㪐㩷

㪄㩷

㪦㪩㪠㪞㪠㪥㪘㪣㩷㪚㪘㪧㪘㪚㪠㪫㪰㩷

㪄㩷

㪎㪏㩷

㪈㪌㪐㩷 㪈㪌㪏㩷㪐㪏㪐㩷㪘㪛㪭㪘㪥㪚㪜㪛㩷㪫㪩㪜㪘㪫㪤㪜㪥㪫㩷㪧㪩㪜㪪㪜㪥㪫㩷㪚㪘㪧㪘㪚㪠㪫㪰㩷

㪘㪉㪦
㪂㪘㪦㩷

㪈㪈㪐㩷

㪄㩷
㪍㪈㩷

㪎㪉㩷
㪄㩷

㪐㪇㩷
㪄㩷

㪌㪎㩷

㪘㪦㩷

㪪㪫㪜㪧㩷

㪄㩷

㪄㩷

㪄㩷

㪄㩷

㪏㪊㩷

㪌㪋㩷

㪐㪇㩷

㪈㪌㪐㩷 㪈㪌㪏㩷㪐㪎㪌㩷㧔Capacity:㧖103m3/Day㧕

2. Adoption of Advanced Treatment(1) Renovation ProjectԘ Investigation of introducing process
Low construction and maintenance costs, as well as maintenance efficiency havebeen the first priority in choosing the advanced treatment process. In case of E and F
lines, which have the same structure as G and H lines, the AO process was adopted forthe phosphorus removal by installing mixers instead of diffuser plates in reaction
tanks.
In case of the renovation of G and H lines, introducing process was investigated by- 170 -

adding Step-Feed Biological Nitrogen Removal Process (STEP), which had beendeveloped by Japan Sewerage Works Agency (JSWA) and was just authorized, as one of
the alternative processes. After careful investigation, the STEP process was chosen for
the following reasons; 1) Step feed channels are already installed in those treatment
lines and large scale construction is not necessary. 2) Equipping mixers in reaction
tanks instead of diffuser plates is adequate for a conversion into an advanced
treatment process. 3) Nitrogen concentration might not meet the future effluent water
quality standard.
ԙ STEP Process
Fig-1 is the illustration of the two-stage STEP process. Half the amount ofwastewater flows into the first stage. In the first denitrification tank, nitrified nitrogenin return sludge is mainly denitrified. In the first nitrification tank, ammonium
nitrogen in the influent wastewater into the first stage is nitrified. The nitrified liquor
flows into the second denitrification tank together with the remaining influent
wastewater is denitrified by using organic carbon in the wastewater. In the second
nitrification tank, ammonium nitrogen in the remaining half of influent wastewater isnitrified. Theoretical nitrogen removal ratio in the case of a 50% return sludge rate is67%.

Fig-1 Illustration of the two-stage STEP processԚ Renovation design
Table-2 shows the design factors of the STEP process introduced into G and H lines.
Table-2 Design factors of the STEP process
Number of Stages

2

Volume Ratio of 1st and 2nd Stage1䋺1.5

Volume Ratio of Denitrification and Nitrification Tank

1䋺1

Influent Volume Ratio into 1st and 2nd Stage

1䋺1

Treatment Capacity

54,000 m3/Day

Return Sludge Ratio

50%- 171 -

As will be mentioned afterward, the influent loading is relatively low, so two-stage
system was adopted for maintaining anaerobic condition in the denitrification tanks.
Influent volume ratio into the first and second stages is fixed at 1:1. Tank volume ratioof the first and second stages is set at 1:1.5 in order to equalize solids quantity in bothstages. Tank volume ratio of both the denitrification and nitrification tanks is fixed fora general value of 1:1. The designed treatment capacity becomes 54,000 m3/D which is
60% of the original conventional treatment capacity of 90,000m3/D.
(2) Renovation works
Ԙ Renovation of facilities
Renovation works of G and H line for advanced treatment was carried out by way of
renewal of diffusers in reaction tanks. The works of G line were completed in March
2003 after approximately a year of construction, and those of H line were completed in
October 2004. Table-3 indicates the outline of the renovation works. Reaction tanks
had been divided into four equal parts by baffle plates before the renovation, and it was
re-divided into four parts so as to make the volume ratio of the first denitrification tank,first nitrification tank, second denitrification tank and second nitrification tank into
1:1:1.5:1.5. In the first denitrification tank, 4 propeller type mixers per sub line were
installed and in the second denitrification tank, 6 mixers per sub line were installed. As
each treatment line consists of 4 sub lines, a total of 40 mixers were installed in eachline. In both the first and second nitrification tanks, super fine bubble membranediffusers made by urethane plastic were installed. Half the amount of wastewater
which flows into the second denitrification tank is led through unused step channels byconstructing the mouth of the channel near the inlet of the second denitrification tank.
Table-3 Outline of the renovation works
㩷Partition

Diffusion and
MixtureStep Feed Channel

before renovation

after renovation䋱䋺䋱䋺䋱䋺䋱

1䋺1䋺1.5䋺1.5
1st Denitrification Tank

Propeller type Mixer, 4units/tank

Ceramic Diffuser

1st Nitrification Tank

Urethane Diffuser Plate, pore 150Ǎm

pore 400Ǎm

2nd Denitrification Tank

Propeller type Mixer, 6units/tank

2nd Nitrification Tank

Urethane Diffuser Plate, pore 150Ǎm

Unuseduse by constructing inflow gatesԙ Construction cost
Table-4 shows the equipment and construction costs of the renovation into the STEP
process, and those of the suppositive renovation into the conventional process of which
treatment capacity is 90,000m3/D. The construction costs per treatment capacity of the
STEP process is 65% higher than that of the conventional process. But the construction
cost itself is actually almost the same for both processes due to the high cost of diffusers
compared with mixers, and due to the unnecessary of construction of the new stepchannel.

- 172 -

(3) Efficiency of introducing STEP processԘ Influent water quality
Table-5 indicates the influent quality into the reaction tank of G and H line. Water
quality of all constituents, except suspended solids, is lower than those researched by
Japan Sewerage Works Agency (Technical evaluation report of STEP Process, 2002)
and Public Works Research Institute (Report of investigation project for facility designof advanced treatment, 2003). This is mainly caused by dilution of the influent
wastewater due to a high underground water level. Maintenance of the biologicalnitrogen removal processes under such low pollutant loading is supposed to be difficult
because the low loading makes anaerobic conditions hard to maintain in the
denitrification tank
Table-4 Equipment and construction costs of the renovation into STEP process
STEP Process㩷equipment
cost

Quantity

unit cost

diffuserhalf of tankmixer

Conventional Process
cost

quantity

unit cost

52,000208,000

whole tank

77,00040

2,000

80,000---

inlet weir

8

4,000

32,0004

4,000

16,000others--

12,000--12,000

total

332,000

336,000

construction and other cost

308,000

308,000

total cost

640,000

644,000

cost
308,000(:103 yen)treatment capacity

54,000 m3/D

㩷

90,000 m3/D

total cost/capacity

11,900 yen/m3

㩷

7,200 yen/m3

Table-5 Influent water quality into reaction tank
Toba Plant

Report by JSWA

Report by PWRI

Average in 2005

Range

Average

BOD

47

60䌾147

121

SS

37

37䌾185

61

T-N

14

19䌾29

25

NH4-N

8.8

14䌾19

16

T-P

1.4

2.9䌾4.3

3.45

PO4-P

0.6

1.6䌾1.9

1.67

㩷

(: mg/L)ԙ Operational condition
Table-6 shows the operational condition of the STEP process in G line as well as the
AO process and conventional process for comparison. Average return sludge ratio is
49% which is almost the same as the designed value of 50%. Average MLSS in reaction
tank is 1,210mg/L which is quite low due to the low influent pollutant loading and isalmost same as both the AO and conventional processes. Average ratio of supplied air- 173 -

volume per treated wastewater is 1.9. In winter season, as influent loading becomes
rather high, so the ratio rises to 2.2 in order to keep MLDO in required degree.
Table-6 Operational condition of each process
STEP㩷

Average

Influent Volume(m3/D)

AO

Conventional

Max

Min

49,23053,14040,01066,98062,330Return Sludge Ratio

(%)

49

51

43

24

35

HRT in Reaction Tank

(hr)

12.6

14.0

11.8

9.1

9.7

MLSS

(mg/L)

1,210

1,400

1,050

1,120

1,180

BOD-SS Loading(kg/kg D)

0.08

0.10

0.05

0.11

0.10

A-SRT

(Day)

7.2

11.0

5.9

9.7

11.6

Air Volume Ratio(m3/m3)

1.9

2.2

1.6

2.9

2.3

(: monthly average in fiscal year 2005)

Ԛ Treatment result
In Table-7, the mean value of influent and effluent water quality of each treatment
process, as well as the removal rate, is shown from the period of April 2005 to March
2006.
Table-7 Water quality and removal rate
㩷

Influent

STEP

AO

Conventional

C-BOD(mg/L䋩

47

1.0

1.6

1.9

SS

(mg/L䋩

37

1.1

1.3

2.3

T-N

(mg/L䋩

14

4.1

8.4

8.4

NH4-N

(mg/L䋩

8.8

0.0

0.3

0.2

N Removal Rate (%)

䋭

70.0

39.0

39.0

T-P

(mg/L䋩

1.4

0.58

0.22

0.67

PO4-P

(mg/L䋩

0.60

0.52

0.13

0.57

P Removal Rate (%)

䋭

57.6

83.6

50.6

a. Nitrogen removal
Effluent total nitrogen concentration of the
STEP process is 4.1mg/L which is less thanhalf value of the AO and conventional
processes. As for the removal rate, 70% on
average is achieved in the STEP process
which is almost identical to the theoreticalvalue, while only 40% is achieved in the AO
and conventional processes. Fig-2 shows abreakdown of the nitrogen removal rate.

㪩㪼㫄㫆㫍㪼㪻㩷㪥㪹㫐㩷㪜㫏㪺㪼㫊㫊㪪㫃㫌㪻㪾㪼
㪉㪉㩼㪛㪼㫅㫀㫋㫉㫀㪽㫀㪼㪻㪥㪋㪏㩼㪜㪽㪽㫃㫌㪼㫅㫋
㪦㫉㪾㪸㫅㫀㪺㩷㪥㪍㩼㪜㪽㪽㫃㫌㪼㫅㫋
㪥㪦㫏㪉㪋㩼

Fig-2 Breakdown of nitrogen removal rate

- 174 -

㪈㪇㪇
㪙㪦㪛㪆㪥

㪥㩷㪩㪼㫄㫆㫍㪸㫃㩷㪩㪸㫋㪼㩷㩿㩼㪀Of this 70% total, 48% of nitrogen is removed by denitrification and 22% of it isremoved by excess sludge.
As shown in Fig-3, the nitrogen removal rate decreases to 63% in summer season. In
order to progress denitrification smoothly, organic matter concentration is regarded as
an important factor and the BOD/N ratio required for denitrification is reported to beat least 2 to 3gBOD/gN. As shown in Fig-4, the minimum ratio is 3.7gBOD/gN in Toba
plant, and as for ratio the sufficient value is maintained.

㪏㪇
㪍㪇

㪏
㪍
㪋
㪉
㪇
㪘㫇㫉㪅

㪋㪇
㪘㫇㫉㪅

㪘㫌㪾㪅

㪡㫌㫃㪅

㪛㪼㪺㪅

㪦㪺㫋㪅

㪡㪸㫅㪅

㪤㫆㫅㫋㪿

㪤㫆㫅㫋㪿

Fig-4 Variation of BOD/N ratio㪥㩷㪩㪼㫄㫆㫍㪸㫃㩷㪩㪸㫋㪼㩿㩼㪀Fig-3 Variation of nitrogen removal rate
But the relationship between influent BOD
concentration and the nitrogen removal rate
shown in Fig-5 indicates that both have astrong relation and the nitrogen removal rate
decreases as influent BOD decreases.

㪏㪇
㪎㪇
㪍㪇
㪌㪇
㪈㪌

㪊㪌

㪌㪌

㪎㪌

㪠㫅㪽㫃㫌㪼㫅㫋㩷㪙㪦㪛㩿㫄㪾㪆㪣㪀Fig-5 Influent BOD and N removal rate
This means that even if the BOD/N ratio is sufficient, it is difficult to keep anaerobic
conditions in the denitrification tank when MLDO concentration in the nitrification
tank come to be excessive, especially in summer season on account of low BOD loading.
b. Operational and maintenance cost
In Table-8, power consumption for mixers in the denitrification tank, air supply inthe nitrification tank of the STEP process, and that for air supply in the conventional
process is shown.
Table-8 Comparison of power consumption in reaction tank
STEP㩷

㩷

Conventional

Power for Mixer(kWh/D)1,633 㩷

䋭Power for Blower(kWh/D)

1,755 㩷2,689 㩷Total Power(kWh/D)3,388 㩷2,689 㩷Influent Volume(m3/D)

49,230 㩷

62,330 㩷

Power for Blower/Influent Volume(kWh/m3)

0.036

0.043

Total Power/Influent Volume(kWh/m3)

0.069㩷

0.043- 175 -

㩷

Even though the power consumption for blower per influent volume of the STEP
process (0.036kWh/m3) is lower than that of the conventional process (0.043kWh/m3),
total power consumption by adding the consumption for mixers (0.069kWh/m3)
becomes higher. Therefore, intermittent operation of mixers has been investigated anda blower with inlet-vanes has been adopted in order to reduce power consumption.

3. Conclusion
As a result of introducing the STEP process into the existing conventional facility at
Toba plant by way of renovation of diffusers, it was found that even though theconstruction cost of the STEP process per treatment capacity is 65% higher than that of
the conventional process and the power consumption of the process per influent volume
is higher than that of the conventional process by 60%, a nitrogen removal rate of
approximately 70% which is almost identical to theoretical value, was achieved.
Kyoto city will be promoting the adoption of the advanced treatment steadily andwill also be investigating its efficient operation and maintenance.

- 176 -

- 177 -Location of Kyoto City

Kyoto City

Water and Sewerage Works Bureau

Kiyohiko Hayashi

Renovation of secondary treatment
facility into the Step-Feed BiologicalNitrogen Removal Process byeffective use of the existing structure

Sewered Area

• More than 1200 years of history,• Around 1.4 million of population,• Located in midstream of the Yodo River,• The Yodo River water is used for drinking
by more than 11 million people in thelower part of the river,

Kyoto City- 178 -Ozonation• ColorAnaerobic-anoxic-oxic process
Anaerobic-oxic activated sludge process• Phosphorus

Anaerobic-anoxic-oxic process
Step-feed biological nitrogen removal process• Nitrogen

Adoption of Advanced Treatment

Percentage of Sewered Population

Ozonation• ColorAnaerobic-anoxic-oxic process
Anaerobic-oxic activated sludge process• Phosphorus

Anaerobic-anoxic-oxic process
Step-feed biological nitrogen removal process• Nitrogen

Adoption of Advanced Treatment

Ozonation• ColorAnaerobic-anoxic-oxic process
Anaerobic-oxic activated sludge process• Phosphorus

Anaerobic-anoxic-oxic process
Step-feed biological nitrogen removal process• Nitrogen

Adoption of Advanced Treatment

- 179 -• Started operation→ 1939• Treatment area
→ 8,191 ha• Population in the area → 771,200• Treatment capacity→ 975,000 m3/D

Toba Wastewater Treatment Plant

Ozonation• ColorAnaerobic-anoxic-oxic process
Anaerobic-oxic activated sludge process• Phosphorus

Anaerobic-anoxic-oxic process
Step-feed biological nitrogen removal process• Nitrogen

Adoption of Advanced Treatment

1993

1996

1999
year

2002

Photo of Toba Wastewater
Treatment Plant

6000006500007000007500008000002005

Decrease of Influent Wastewater
Influent to Reaction Tank
(m3/D)

- 180 -

-

AO
A2O

119

ADVANCED
TREATMENTPRESENT CAPACITY(*103m3/D)

61

78

-

ORIGINAL CAPACITY(*103m3/D)

B

A

TREATMENT LINE

57

-

72

C

57

-

72

D

83

AO

90

E

83

AO

90

F

54

S

90

G

54

S

90

H

90

-

90

I

J

K

-

159 158-

159 158

Treatment Capacity of Toba
Treatment Plant

Area of the Plant

Treatment Processes

Treatment Lines

- 181 -Reasons of Choosing STEP Process
1) Step feed channels are already installedin those treatment lines.
2) Equipping mixers instead of diffuser
plates is adequate for a conversion into
an advanced treatment process.
3) Nitrogen concentration might not meetthe future effluent water quality standard.

1) Step feed channels are already installedin those treatment lines.
2) Equipping mixers instead of diffuser
plates is adequate for a conversion into
an advanced treatment process.
3) Nitrogen concentration might not meetthe future effluent water quality standard.

1) Step feed channels are already installedin those treatment lines.
2) Equipping mixers instead of diffuser
plates is adequate for a conversion into
an advanced treatment process.
3) Nitrogen concentration might not meetthe future effluent water quality standard.

Reasons of Choosing STEP Process

Reasons of Choosing STEP Process

Layout of the Plant

- 182 -

PO4-P

T-P

NH4-N

T-N

SS

BOD

Report by
JSWA
Range

60～14737～18519～29
14～19
2.9～4.3
1.6～1.9

Toba Plant

Average in
2005

47
37
14
8.8
1.4
0.6

121
61
25
16
3.45
1.67

Average

Report by
PWRI

Influent Wastewater Quality

Illustration of two-stage STEP process

1：1

Volume Ratio of Denitrification
and Nitrification Tank
Influent Volume Ratio into 1st and 2nd
Stage

50%

Return Sludge Rate

Step Feed
ChannelDiffusion
andMixturePartition

unusedCeramic
Diffuser
pore
400μm

１：１：１：１

beforerenovation

use by constructing inflow gates

Urethane Diffuser
Plate, pore 150μm

Propeller type Mixer,
6units/tank2nd Denitrification
Tank
2nd Nitrification Tank

Urethane Diffuser
Plate, pore 150μm

Propeller type Mixer,
4units/tank
1st Nitrification Tank

1st DenitrificationTank

1：1：1.5：1.5

after renovation

Outline of Renovation Works

54,000 m3/D

Treatment Capacity

1：1

1：1.5

2

Volume Ratio of 1st and 2nd Stage

Number of Stages

Design Factors of STEP Process

- 183 90,000 m3/D
7,200 yen/m3

11,900 yen/m3
total cost/capacity(103 yen)

644,000

308,000

336,000

28,000-308,000

whole tankcost

54,000 m /D

44,00080,000quantity

Conventional
Process

treatment capacity3

640,000

332,000

total cost-

cost
208,000

308,000

total

others40

half of tankconstruction costequipment costmixer

diffuserquantity

STEP Process

Cost for Renovation

(hr)HRT in Reaction
Tank

7.2

1.9

(m3/m3)

0.08

(Day)

(kg/kg D)

1,210

12.6

49

49,230

2.2

11.0

0.10

1,400

14.0

51

53,140

Max

1.6

5.9

0.05

1,050

11.8

43

40,010

Min

2.9

9.7

0.11

1,120

9.1

24

66,980

AO

2.3

11.6

0.10

1,180

9.7

35

62,330Conventional

Denitrified N
48%

Effluent
Organic N
6%

Effluent NOx
24%

Removed N by
Excess Sludge
22%

Breakdown of Nitrogen Removal Rate

Air Volume Ratio

A-SRT

BOD-SS Loading(mg/L)(%)

Return Sludge
Ratio

MLSS

(m3/D)

Influent Volume

Average

47

1.0

0.58
0.52

1.4
0.60
－

(mg/L）(mg/L）PO4－Ｐ
P Removal Rate (%)

83.6

50.6

0.57

0.67

39.0

0.2

8.4

2.3

1.9

Conventional

40

60

80

100

Apr.

Aug.

Month

Dec.

Variation of Nitrogen Removal Rate

57.6

0.13

0.22

39.0

70.0

Ｔ－Ｐ

0.3

8.4

1.3

1.6

AO

0.0

－

4.1

1.1

N Removal Rate (%)

14

37

8.8

(mg/L）(mg/L）(mg/L）STEP(mg/L）

ＮＨ４－Ｎ

Ｔ－Ｎ

ＳＳ

Ｃ－ＢＯＤ

Influent(from Apr. 2005 to Mar. 2006)

STEP

Water Quality and Removal Rate

Operational Condition(monthly average in fiscal year 2005)

N Removal Rate (%)- 184 -

- 185 -55
Influent BOD(mg/L)

75

0.036
0.069

(kWh/m3)(kWh/m3)

Power for Blower/Influent
VolumeTotal Power/Influent Volume

0.043

0.043

62,330

2,689

2,689

• Approximately 70% of nitrogen removal
rate is achieved.
• Construction cost and operational cost of
the STEP process per influent volume arehigher than those of conventional processby 65% and 60% respectively.
• In order to reduce the operational cost,some measures have been investigated.

35

49,230(m3/D)

Influent Volume-

Conventional• Approximately 70% of nitrogen removal
rate is achieved.
• Construction cost and operational cost of
the STEP process per influent volume arehigher than those of conventional processby 65% and 60% respectively.
• In order to reduce the operational cost,some measures have been investigated.

15

3,388

(kWh/D)

Total Power

1,755

1,633

(kWh/D)(kWh/D)Power for Blower

Power for Mixer

STEP

Power Consumption in Reaction Tank

Conclusion

50

60

70

80

Influent BOD and Nitrogen
Removal Rate

Conclusion

Nitrogen Removal Rate(%)

- 186 -Discharging Rivers• Approximately 70% of nitrogen removal
rate is achieved.
• Construction cost and operational cost of
the STEP process per influent volume arehigher than those of conventional processby 65% and 60% respectively.
• In order to reduce the operational cost,some measures have been investigated.

ConclusionEND

- 187 -BOD/N

ORP(mV)

Apr.

Jul.
Month

Oct.

Jan.

-250

-150

-50

50

0

1

3

MLDO(mg/L)

2

4

MLDO in the 1st nitrification tank and
ORP in the 2nd denitrification tank

0

2

4

6

8

Variation of BOD/N Ratio

5

P removal rate（％）

(mg/L）（％）(mg/L）

N removal rate

T-N
T-P

1

2
MLDO(mg/L)

3

4

1.8

16

61

51.7

0.87

9.2

2.0

outflow
to river42.5

inflow toreactor

E：conventional
F：conventional
G：conventional
H：conventional
I：conventional

1995～1997

1.6

15

51

61.9

0.61

9.0

1.8

outflow
to river40.0

inflow toreactor

E：AO
F：AO
G：conventional
H：conventional
I：conventional

2000～2002

5

1.4

14

46

72.9

0.38

7.4

1.6

Outflow
to river47.1

inflow toreactor

E：AO
F：AO
G：STEP
H：STEP
I：conventional

2005

Outflow Quality to the River

0(mg/L）

0

0.2

0.4

0.6

0.8

in the 1st Nitrification Tank

MLDO and Residual NH4-N

BOD

Residual NH4-N(mg/L)

- 188 -(mg/L)(mg/L)

T-N

T-P

1.1

7.8

5

0.6

5.7

3

Master Plan (*2)

2nd Recycle Flow

1st Recycle Flow

Recycle Flow from
Sludge Treatment

Incinerator

Dewatering

Digestion Tank

Sludge Thickener

Main Source

60,200m3/D

35,300m3/D

Volume39
11

T-N (mg/L)
T-P (mg/L)

602

450

BOD (mg/L)
S S (mg/L)

17(mg/L)

T-P

70

967

610

(mg/L)(mg/L)(mg/L)

T-N

S S

BOD

Water Quality

Recycle Flow Quality(*1) Osaka bay, the Yodo river comprehensive basin-wide planning ofsewerage systems(*2) Master Plan of Kyoto City up to 2025, treatment by nitrogen andphosphorus removal, sand filtration and ozonation(mg/L)

BOD

Basin-wideplanning(*1)

Target Effluent Water Quality

SludgeTreatment
SectionSubsection 2

Wastewater
Treatment
Section 2

Subsection 1

Wastewater
Treatment
Section 1• Target year : 2025
1 sewered population of 100%
2 storm water management
3 improvement of CSO
4 advanced treatment
5 sludge treatment
6 renovation and earthquake proof
7 multi-use of facilities and resources

The master plan of sewerage
works of Kyoto City

Administration
SectionDirector

Organization of Toba Plant

- 189 -

14

4.1

70%

Effluent-N

Removal Rate

(mg/L)(mg/L)

Influent-N

3.3

Nitrifiable-N
0.8

3.1

Excess sludge-N

Unnitrifiable-N

0.8

10.1

Unnitrifiable-N

Nitrifiable-N

67%

3.3

10.1

Breakdown of Nitrogen Removal

Installation of Mixers

Benefit(after installation)

2006(before installation)

2005

28%

12,300 kWh/Day

17,100 kWh/Day

Power Consumption by Blower(May to August)

Effect of Installing
Blower with Inlet-Vanes

Fäkalschlammmitbehandlung als Mittel
zur Kläranlagenbetriebskostensenkung

1

Projekt-Nr. 02-WA 9745/0

Treatment of Sludge from Septic Tanks in Municipal Wastewater Treatment Plants
Dipl.-Ing. Clarisse Harlay, Prack Consult GmbH,I.

GeneralPrack Consult GmbH is a consultant engineer acting world-wide a.o. in theenvironmental field. The R&D activity of Prack Consult is always close to the practiceand related to the projects Prack is working for. Prack Consult as a middle size
company often carries out its - always practice related - R&D projects with the supportof the BMBF. One of the latest project was realised in Thailand in the years 20002004: “Transfer and adaptation of sewage sludge treatment in reed beds to Thailand
standards”.
Today’s presentation deals with the R&D project “Co-treatment of faecal sludge as amean for operation cost-reduction on wastewater treatment plants”, realised between
1998 and 2001.

II.

Introduction
In 1996, the year the idea of the project was born, many millions inhabitants in theformer Eastern Germany were not connected to a central wastewater treatment plant(WWTP). Most of the wastewater was treated in septic tanks and disposed off asfaecal sludge. A connection of these inhabitants to central – state of the art wastewater treatment plants was not possible in the short to medium term. On theother side many newly built wastewater treatment plants in the new “Länder” were notworking on full loading capacity. The target of the R&D project was to close the gap
between the overproduction of poorly treated faecal sludge and not utilised treatment
capacities in central WWTPs on the other side.

III.

Treatment of sludge from septic tanks in municipal wastewater treatment plants
The R&D project was realised between 1998 and 2001 in co-operation with awastewater treatment plants building company and the Neustrelitz’s (MecklenburgVorpommern) department of works. It includes 3 main parts:-

a research on the actual status of sludge treatment in Germany,-a pilot-plant test in a container wastewater treatment plant over 2 years-

an economic research.

The main results of the project are presented in the following.

Prack Consult GmbH
Beratender Ingenieur

19.09.2006- 191(747_Neustrelitz/Sonstiges/060914PC747_F+E-Sludge-Neustrelitz.doc)-

Fäkalschlammmitbehandlung als Mittel
zur Kläranlagenbetriebskostensenkung

1.

2

Projekt-Nr. 02-WA 9745/0

Actual status of sludge treatment in Germany
The target of the research was to review the actual situation with regards tosludge out of septic tank in former Eastern Germany and to define the frame of
applicability for faecal sludge treatment in central municipal treatment plants,
i.e. to define the potential market for the research “results”.

In Germany the municipalities are responsible for the wastewater – thus forthe faecal sludge – disposal and treatment. This task is often transferred to awastewater operation company. The transport of faecal sludge is however for
80 % realised by third parties, the treatment of the sludge takes place in 51 %of the cases on a wastewater treatment plant of the company.

In 1998 about 5 million inhabitants or 30 % of the population of the former
Eastern Germany were not connected by pipe to central WWTPs. About 85 %of them were connected to septic tanks. Even if the connection rate to central
WWTPs still grows, in many rural area the rolling sewerage – i.e. the transportof faecal sludge in tank trucks – and co-treatment of faecal sludge in municipal
wastewater treatment plants will still be important in future.

2.

Pilot plant test
In Germany the co-treatment of faecal sludge in municipal wastewater
treatment plants is regulated in the ATV-A-123. According to this working
sheet

of

the

GermanWastewater

Association(Abwassertechnische

Vereinigung ATV) each WWTP with more than 10,000 p.e. (people equivalent)
design capacity and sufficient capacities can treat up to 20 m³/d faecal sludge
per 10,000 p.e., without any analysis of the faecal sludge. The inflow should
not exceed 5 % of the wastewater inflow. As per ATV-A-123 the following
polluting loads are admitted for faecal sludge:

Parameter

Unit

Min.-Value ATV

Mean Value ATV

BSB5

mg / l

500

2,500

5,000

CSB

mg / l

1,000

6,000

15,000NH4-N

mg / l

100

300

500

Ptot

mg / l

50

150

400

Table 1:

Max.-Value ATV

Polluting loads in faecal sludge as per ATV-A-123

The table shows that the concentrations have high range of value and that two
different faecal sludge batch can differ from 1 to 15. Compared to municipal
Prack Consult GmbH
Beratender Ingenieur

19.09.2006- 192(747_Neustrelitz/Sonstiges/060914PC747_F+E-Sludge-Neustrelitz.doc)-

Fäkalschlammmitbehandlung als Mittel
zur Kläranlagenbetriebskostensenkung

3

Projekt-Nr. 02-WA 9745/0

wastewater faecal sludge is highly concentrated and has a low BSB5/CSBratio.

The aim of the R&D project was to define the limits of the co-treatment of
faecal sludge in municipal wastewater treatment plants. It was chosen to workon the Neustrelitz WWTP (designed by PC), with a capacity of 100,000 p.e.,and 3 lines. The tests were realised in 2 container-WWTP since the faecal
sludge quantities were not available for a test in the WWTP. One container
was the reference, exclusively fed with municipal wastewater. The second
container had an initial load with 85 % (of the total design capacity, expressedin volume) municipal wastewater and was fed also with faecal sludge (up to80 %).

Figure 1: Container for the pilot plant test

The main results of the test are that – under the premises of an adapted inputof faecal sludge in the WWTP all over the day – the quality of the effluent is up
to the highest request in Germany with a faecal sludge addition up to 50 % involume. A treatment of the faecal sludge alone in the container WWTP lead toan effluent quality as requested for a WWTP of small size. In short faecal
sludge can be co-treated in municipal WWTP in much higher concentration as
usually done according to the ATV-A 123, if the quality of the sludge iscontrolled beforehand.

Prack Consult GmbH
Beratender Ingenieur

19.09.2006- 193(747_Neustrelitz/Sonstiges/060914PC747_F+E-Sludge-Neustrelitz.doc)-

Fäkalschlammmitbehandlung als Mittel
zur Kläranlagenbetriebskostensenkung

3.

4

Projekt-Nr. 02-WA 9745/0

Economic research
Three alternatives of the wastewater treatment in rural areas – taking
Neustrelitz as an example – were investigated:-first, the treatment in septic tanks with transport of the sludge to the central
wastewater treatment plant in Neustrelitz,-

in second, the connection of the population to a local sewerage and a local
WWTP with a design capacity of about 1,000 p.e.,-in third, the connection of the total population to the central WWTP
Neustrelitz over sewerage.

Taking into consideration the investment and operation costs over a period oftime of 25 years, the disposal of wastewater in septic tanks with co-treatmentof the sludge in central WWTP is the most economic variant.

For the WWTP, the co-treatment of faecal sludge – to fill not utilised existing
capacity – can lead to substantial cost reductions.

IV.

Conclusions
The co-treatment of faecal sludge can be realised in municipal WWTP at a muchhigher degree as commonly admitted in Germany, keeping the high quality of theeffluent, if the faecal sludge is added according to its quality and to the actual load of
the WWTP. This co-treatment can lead to substantial wastewater treatment costreduction (up to 0.25 €/m³).

Basing on the results of the R&D-project, Prack Consult GmbH developed a measure
and control unit for faecal sludge stations on WWTP (registered utility model). This
unit will allow a higher faecal sludge input, adapted to the existing wastewater flow
and the capacity of the wastewater treatment plant.

Prack Consult GmbH / Har

Heide, 19.09.2006

Development Consultants

Prack Consult GmbH
Beratender Ingenieur

19.09.2006- 194(747_Neustrelitz/Sonstiges/060914PC747_F+E-Sludge-Neustrelitz.doc)-

- 195 Sanitary engineering

Road construction

Rundu

Prack Consult GmbH – Development Consultants

PolandKrakow, Stettin

Namibia
BangkokThailand

Murdeira / Sal

Cape VerdeInfrastructure and land development

Structural engineering

Project offices abroad

Marine and coastal engineering

Co-ordination

Head Office
Heide, Germany

Prack Consult GmbH
Development Consultants

Organisation

2

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Solid waste management

R&D Project
Company
Presentation

Prack Consult GmbH – Development Consultants

Research on the actual status of sludge treatment inTreatment of Sludge
from Septic Tanks in Municipal
Wastewater Treatment Plants

Economic researchover 2 years

3

Pilot plant test in a container wastewater treatment plant

Germany

1Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Prack Consult GmbH – Development Consultants

III.

II.

I.

R&D Project

Prack Consult GmbH – Development Consultants

Mail: PrackConsult@t-online.dewww.prackconsult.de

Tel.: ++ 49 (481) 6 80 7-0
Fax: ++ 49 (481) 6 75 31

Lüttenheid 7925746 Heide / Germany

Prack Consult GmbH

Development Consultants, Heide

Presentation

Prack Consult GmbH

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Development Consultants, Germany

R&D Project
Company
Presentation

Prack Consult GmbH

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants„Treatment of sludge from septic tanks
in municipal wastewater treatment
plants“

R&D Project

- 196 -In central WWTPs (75 %)Agricultural utilisation (11%)
Composting (4 %)Dumping on landfill (2 %)Separate treatment plant (1 %)Prack Consult GmbH – Development Consultants-

Treatment of the Sludge:

6

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Actual Status of Sludge Treatment (1998)

R&D Project

Prack Consult GmbH – Development Consultants

Former Eastern Germany- 16 Mio. Inhabitants- 70.0 % connected to central WWTP

Former Western Germany:- 66 Mio. Inhabitants- 93.5 % connected to central WWTP

4

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Actual Status of Sludge Treatment (1998)

R&D Project

Prack Consult GmbH – Development Consultants

7

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Pilot Plant Test (1999-2001)

R&D Project

Prack Consult GmbH – Development Consultants- Cesspools- Septic tanks- Small WWTP without sludge treatment

Origin of the sludge:

5

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Actual Status of Sludge Treatment (1998)

R&D Project

> 10,000 p.e. design capacity
Sufficient capacity
20 m³ per 10,000 p.e.
< 5 % of wastewater inflow

Prack Consult GmbH – Development Consultants-

Boundary conditions for the co-treatment of
Sludge in WWTP:

10Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Pilot Plant Test (1999-2001)

R&D Project

Prack Consult GmbH – Development Consultants

8

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Pilot Plant Test (1999-2001)

R&D Project

FS-AS

VF 25

VB

VF
40

SF KA-NZ

VF
32

BB 2

C-KLA 2

NK 2

SS 2

mg / lmg / lmg / l

COD
NH4-N
Ptot

50

100

1,000

500

150

300

6,000

2,500

400

500

15,0005,000

Min.-Value
Mean
Max.ATV
Value ATV Value ATV

Prack Consult GmbH – Development Consultants

mg / lBOD5

Unit

Polluting loads in Faecal Sludge
as per ATV-A- 123:
Parameter

E2

KA-NZ

9

KA-NZ

11

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

C-KLA 1

NK 1

Pilot Plant Test (1999-2001)

R&D Project

Prack Consult GmbH – Development Consultants

AW

FS

BB 1

SS 1

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Pilot Plant Test (1999-2001)

R&D Project

E1- 197 -

- 198 -

0

50

100

150

200

250

300

BOD

COD

Norg

NH4

PO4

TS

pH

12

- Connection of the population to a local WWTP

- Not sufficiently treated sludge

Prack Consult GmbH – Development Consultants- Treatment in cesspools with transport of sludge
to a central WWTP

- Central wastewater treatment plants with freetreatment capacities

Prack Consult GmbH – Development Consultants- Connection to a central WWTP

Approach:

15

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Economic research

R&D Project

Prack Consult GmbH – Development Consultants- Sole treatment of faecal sludge leads to effluent
quality as requested for small WWTP (up to
1,000 p.e.)- Co-treatment of up to 50 % Sludge (in vol.) with
effluent quality up to highest German Standards

Results of the tests:

13

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Pilot Plant Test (1999-2001)

R&D Project

Why:

14

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Economic research

R&D Project

Ptot

Parameter

No3

Mean concentrations in Faecal Sludge (compared to municipal
wastewater = 100 %)Prack Consult GmbH – Development Consultantsvalue]

Faecal sludge and wastewater:

LF

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Pilot Plant Test (1999-2001)

R&D Project

Faecal Sludge concentration [%-- 199 -- Septic tanks, transport to and treatment of thesludge in a central WWTP is the most economic
solution- Transport costs

Prack Consult GmbH – Development Consultants- Reduction of the costs through acceptance andtreatment of much higher quantities of faecal
sludge – only possible with a proper faecal
sludge management

For central WWTP:

Results:

18

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Economic research

R&D Project

Prack Consult GmbH – Development Consultants

Thank you foryour attention

Development Consultants, Germany

Prack Consult GmbH

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Prack Consult GmbH – Development Consultants

R&D Project

Prack Consult GmbH – Development Consultants

For regions with a low density of population- Investment costs for the treatment capacity, thesewer and the transport mains- Operation costs

Results:

17

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Economic research

R&D Project

Approach as per LAWA:

16

Treatment of Sludge from Septic tanks in Municipal Wastewater Treatment Plants

Economic research

R&D Project8WLOL]DWLRQRIVHZDJHVOXGJHLQ.LWDN\XVKX&LW\RI-DSDQ

Yasumitsu Kondo
Bureau of construction, Kitakyushu city
14-18, Osayuki-nishi 5-choume, kokuraminami-ku, kitakyushu 803-8501 Japan
Yasumitsu_kondou01@mail2.city.kitakyushu.jp

Abstract: Now, Kitakyushu city has two recycling methods of sewage sludge. The first way is thatdried sludge is burned with refuse at incineration facility located by sewage treatment plant. The
heat energy generated by the burning is recycled as sources such as electric power source for theplant and the source for sludge drying. Secondly, we’ve been materializing sludge for cement since1997. Kitakyushu city is one of the first Japanese cities that introduced this new technology. Bothways are the largest scale ones in Japan. For the next utilization, we are now trying to use sludge as
an efficient fuel by further drying process.
Keywords: cement material, sludge incineration, dewatered sludge, fuelization, super
power generation
Introduction
In Japan sewage sludge tends to increase every year by the spread of sewers, advanced biologicaltreatment, and change of a lifestyle and so on. Along with it more and more difficulties are coming
up in finding appropriate sludge process measures and cost in the treatment. Among municipalities
having wastewater treatment plant (WWTP), there is a local body to have a cement company treat
dewatered sludge (DS) at its factory, far away 600 km from the city with cargo train transportation.
Kitakyushu city introduced Cement Materialization System (CMS) for DS in 1997 and Sludge
Incineration System with generally refuse (SIS) at incineration facilities in 1999 instead of sea
reclamation and sea dumping disposal. By this shift, we had achieved our objective to utilize thesludge for cement material and power generating to a certain extent. Circumstances surrounding
biosolids sludge, however, have been changing these days, as the central government proclaimed
biomass strategy for promotion of its utilization in various fields and “the renewable portfolio
standard” was enacted in 2003 in favour of sludge energy use in response to the Kyoto protocol
enforcement. In line with this movement we have started tackling for the further utilization of
sewage sludge as useful biomass resources with intention of reduction of environmental burden on
our city toward a recycling society. In this paper we introduce our present state of DS treatment andefforts for future biosolids utilization.

- 201 -

2

Utilization of sewage sludge in Kitakyushu City of Japan

Figure1 shows transition of sewage sludge treatment and volume in Kitakyushu city

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㪏㪎

㪏㪏

㪪㪼㪸㩷㫉㪼㪺㫃㪸㫄㪸㫋㫀㫆㫅䇭㽳

㪏㪐

㪐㪇

㪐㪈

㪐㪉

㪚㪼㫄㪼㫅㫋䇭㽴

㪐㪊

㪐㪋

㪐㪌

㪐㪍

㪩㪼㪽㫌㫊㪼㩷㪠㫅䋮䇭㽵㪐㪎㪐㪏㪐㪐 㪉㪇㪇㪇 㪇㪈

㪇㪉

㪇㪊

㪇㪋

㪪㪼㪸㩷㪻㫌㫄㫇㫀㫅㪾䇭㽶Transition of the amount of sewage sludge

The dewatered sludge treatment in Kitakyushu city
(1) Outline of present treatment
Kitakyushu city processes DS by two methods called CMS and SIS. The former is the recycling
method of the sewage sludge developed by joint team consisting of Kitakyushu city and a cementcompany and is utilized in other cities now. Incidentally Kitakyushu’s case serves as the greatest inquantity in Japan. As for the system of CMS, DS is received with a hopper for exclusive use, andthen thrown into a rotary kiln with cement materials, such as limestone, and calcinations process isperformed. Then, rapid cooling is carried out with the clinker cooler and it becomes powderedcement. On the other hand, the steam produced by the boilers of SIS is used as dry source for the
DS drier at WWTP. The SIS generates electricity, a fraction of which is supplied to the WWTP thatpumps up treated water for the incineration facility. In the process, incineration and wastewater
facilities synergistically work.
(2)Destination of DS for treatment
There are 5 WWTPs in this city, and they generate approximately 230 t/day of DS. About 60t out of
230t/day is generated from the Hiagari WWTP(HW) with digestion tanks, and the rest (170t/day) isfrom other WWTPs without digestion process. In addition, half of the daily sludge is turned into
cement materials, and the other half is disposed together with regular household refuse atincineration facilities. In order for the sludge to be transformed as cement material, the sludge istransferred to the Mitsubishi Material Corp.’s facilities both at Kurosaki and Kanda. On the other
hand, the remaining sludge is supplied to the sludge drier in HW. After drying, the sludge is carriedout to the Hiagari and Kougasaki incineration facilities. The destination of DS and its mount ofsludge processed are shown in Fig. 2.

- 202 -

Utilization of sewage sludge in Kitakyushu City of Japan‫‒⁫⁓⁖‡⁦…†․‫‬‥‥„․•†‪⁦‡⁖⁓⁫‒••⁦‡⁫⁗⁓⁤‒„

3․†‪⁦‡⁖⁓⁫‒••⁦‡⁫⁗⁓⁤‒․․„‫‒⁤⁓⁗⁫‡⁦••‫‬
Hiagari

Kitaminato
treatment

treatmentᵏᵎᵌᵗᵩᶋᴾ

Cement company
Kurosaki facility

Kougasakiᵗᵌᵓᵩᶋᴾ

SludgeShinmachi

Dryertreatment

treatment••⁦‡⁫⁗⁓⁤‒‣

treatment

facility․‧†‣⁦‡⁖⁓⁫‒‣‪„․••⁦‡⁫⁗⁓⁤
Kougasaki‣‧†

facility‧„‣••⁦‡‒⁫⁗⁓⁤†‪⁦‡⁖⁓⁫‒‧„‪••⁦‡⁫⁓⁗⁤‒

Sone

Hiagariᵐᵒᵌᵕᵩᶋᴾ

†…⁦‡⁖⁓⁫‒‫„‫‬

ᵏᵗᵌᵎᵩᶋᴾ

ᵎᵌᵏᵩᶋᴾᵏᵌᵐᴾᵩᶋᴾ

․†⁦‡⁖⁓⁫‒„․••⁦‡⁫⁗⁓⁤ᴾ⊗‡⁖⁓⁫‒ᵏᵎᵌᵕᵩᶋᴾ
Cement Material
‒

‒

‒

‒

‒

‒

‒

‒

Cement company

Dry Treatment

Kanda facility
Incinalation with refuse

Fig. 2 Destination of DS and its mount of sludge processed(3) Sludge incineration system with generally refuse (SIS) and power generation
The flow of SIS and diagram of usage of power generated are shown in Figs.3 and 4. As mentioned
above, using the steam generated at the Hiagari Incineration facility (HIF) adjacent to HW, DS isdried in a drier currently installed within㩷 HW and dried pellets are burned by boilers in HIF and
KIF(Kougasaki Incineration Facility). The steam turbines in these facilities generate power using
steam attained, and the power generated is supplied to own facility and HW. The surplus of thepower is provided to a power company in trade. Thus Energy recycle system has been achieved.
㪟㫀㪸㪾㪸㫉㫀㩷㪮㪮㪫㪧㪪 㫋㪼㪸㫄㩷㪻㫉 㫀㪼㫉㩿㪎 㪌㩼㩷㩷㩷㩷㩷㩷㪋㪇㩼㪀㪪㫃㫌㪻 㪾㪼

䇭㪛㪪㩷㪻㫉㫐㩷㪽㪸㪺㫀㫃㫀㫋㫐㪼㫃㪼㪺㫋 㫉㫀㪺㫀㫋㫐㪪㫋 㪼㪸㫄 㩷㫋㫌㫉 㪹㫀㫅㪼㪾㪼 㫅㪼㫉㪸㫋 㫆㫉㪝 㫆㫉㫄㫄 㪸㫂㫀㫅㪾㫄 㪸㪺㪿㫀㫅㪼㫊㫋㪼 㪸㫄㪪 㫋㪼㪸㫄 㩷㪻㫉 㪸㫄㫊㫋㪼 㪸㫄

㪩㪼㪽㫌㫊㪼㩷㫀㫅㪺㫀㫅㪸㫉㪸㫋㫀㫆㫅㩷㪽㪸㪺㫀㫃㫀㫋㫐
Fig. 3㪟 㫆 㫇㫇㪼㫉

Energy recycle system of SIS- 203 -

㪩㪼 㪽㫌 㫊㪼㫀㫅 㪺㫀㫅 㪸㫉㪸㫋㫀㫆㫅㪛㫉㫐㫊㫃㫌㪻㪾㪼㪩 㪼㪽㫌㫊㪼

4

Utilization of sewage sludge in Kitakyushu City of Japan㪮㪮 㪫㪧㪙 㫀㫆㫊㫆㫃㫀㪻 㫊㪛㫉㫐㩷㫊㫃㫌㪻 㪾㪼㪫 㫆㫋㪸㫃㩷㫀㫅 㪺㫀㫅 㪸㫉 㪸㫋㪼㪻 㩷㫍㫆 㫃㫌㫄 㪼㪈 㪎㪇㪃㪇㪇㪇㩷㫋㫆 㫅㩷㫇㪼㫉 㩷㫐㪼 㪸㫉㪈㪏 㪃㪇㪇 㪇㪤㪮㪿㩷㩷㩿㩷㪎 㪃㪇㪇 㪇㫋㪄㪚 㪦 㪉㪀㪩㪼 㪽㫌 㫊㪼 㩷㪾㪼 㫅 㪼㫉㪸 㫋㫀㫆㫅㩿㩷㪍㪃 㪇㪇 㪇 㫂㪮㩷㪀㪠㫅 㪺㫀㫅 㪸㫉㪸㫋㫀㫆㫅㩷㪽㪸㪺㪅㪍㪃㪌㪇 㪇㫋㩷㫀 㫅㪺㫃㫌㪻㪼㪻㪫㫆㫋 㪸㫃㩷㪼㫃㪼㪺㫋 㫉㫀㪺 㫀㫋 㫐㪋㪈㪃㪇㪇㪇㪤 㪮㪿㪉㪈 㪃㪇㪇 㪇㪤㪮㪿㪥 㫆㫅㪄㪹 㫀㫆 㫊㫆 㫃㫀㪻㫊㩿㫇㫃㪸㫊㫋㫀㪺㩷㪸㫅㪻㫆㫋㪿 㪼㫉㫊 㪀㩷㩷 㩷㩷㩷㩷㪪 㪸㫃㪼䇭 㪉㪃㪇 㪇㪇㪤㪮 㪿

Fig. 4 Hiagari incineration facility’s fuel for power and electricity distribution
The most significant point of SIS is that the sludge regarded as mere waste is actually power
generation resources. If we compare power generation efficiency of our facilities to 40% of athermal power plant, 26% at KIF or 10% at HIF is relatively low. However, we can produce thepower we need every day without having an electric generating system itself.
Dewatered sludge drier (DSD)
The drier(water evaporation 2㬍1,800 kg/hr) shown in Fig.5 consists of hopper, sludge feeder, mainpart of the drier, mixer, form making machine, etc.
㪪 㫃㫌 㪻 㪾 㪼 㩷 㪺 㪸 㫂 㪼㪪 㫃㫌 㪻 㪾 㪼 㩷 㪺 㪸 㫂 㪼㪚 㫆 㫅 㫊 㫋㪸 㫅 㫋㩷㪽㪼 㪼 㪻 㪼 㫉䇭 䋨 㫃㫆 㫎 㩷 㫄 㫆 㫀㫊 㫋 㫌 㫉 㪼 䋩㪚 㫆 㫅 㫊 㫋㪸 㫅 㫋㩷㪽㪼 㪼 㪻 㪼 㫉䋨 㪿 㫀㪾 㪿 㩷 㫄 㫆 㫀㫊 㫋 㫌 㫉 㪼 䋩

䌐

䌐

䌐

䌐

㪝 㫆 㫉㫄 㩷㫄 㪸 㫂 㪼 㪻 㩷㪺 㪸 㫂 㪼 㩷㪿 㫆 㫇 㫇 㪼 㫉㪪 㫃㫌 㪻 㪾 㪼 㩷 㫇 㫌 㫄 㫇 㩷 㫋 㫆 㩷 㫄 㫀㫏 㪼 㫉䌐㪚 㫆 㫅 㫊 㫋㪸 㫅 㫋㩷㫍 㫆 㫃㫌 㫄 㪼 㩷㪽㪼 㪼 㪻 㪼 㫉㪪 㫃㫌 㪻 㪾 㪼 㩷 㪻 㫉 㫐 㪼 㫉㪠㫅 㪺 㫀㫅 㪸 㫃㪸 㫋 㫀㫆 㫅 㩷㪽 㪸 㪺 㫀㫃㫀㫋 㫐㪤 㫀㫏 㫀㫅 㪾 㩷 㪻 㪼 㫍 㫀㪺 㪼㪛 㫉 㫀㪼 㪻 㩷 㫊 㫃㫌 㪻 㪾 㪼 㩷 㪽 㪼 㪼 㪻 㪼 㫉㪝 㫆 㫉 㫄 㩷 㫄 㪸 㫂 㫀㫅 㪾 㩷㫄 㪸 㪺 㪿 㫀㫅 㪼㪪 㫋㪼 㪸 㫄 㩷㪿 㪼 㪸 㪻 㪼 㫉㪛 㪼 㫆 㪻 㫆 㫉 㫀㫑 㪼 㪻 㩷㪸 㫀㫉 㩷 㫇 㫉 㪼 㪿 㪼 㪸 㫋 㪼 㫉㪛 㫉 㫐 㩷 㪸 㫀㫉 㩷㫇 㫉㪼 㪿 㪼 㪸 㫋㪼 㫅㪫 㪿 㪼 㫉 㫄 㪸 㫃㩷㫊 㫋㫆 㫉㪸 㪾 㪼 㩷㪻 㪼 㫆 㪻 㫆 㫉 㫀㪄㫑 㪸 㫋 㫀㫆 㫅 㩷㪽㫌 㫉㫅 㪸 㪺 㪼㪪㫋㪸㪺㫂㩷

㪛㪼㪿㫌㫄㫀㪻㫀㪽㫀㪼㫉㩷㪛 㫀㫉 㪼 㪺 㫋 㫃㫐 㩷 㪹 㫌 㫉 㫅 㫅 㫀㫅 㪾 㩷㪽㫌 㫉㫅 㪸 㪺 㪼㪜 㪸 㪺 㪿 㩷 㪻 㪼 㫍 㫀㪺 㪼㪪 㫃㫌 㪻 㪾 㪼 㩷 㪽 㫃㫆 㫎㪞 㪸 㫊 㩷 㪽 㫃㫆 㫎㪪 㫋 㪼 㪸 㫄 㩷 㪽 㫃㫆 㫎㪮 㪸 㫋 㪼 㫉 㩷 㪽 㫃㫆 㫎㪚 㫆 㫅 㪻 㪼 㫅 㫊 㪸 㫋㪼 㩷㫋㪸㫅 㫂㪠㫅 㪺 㫀㫅 㪸 㫃㪸 㫋 㫀㫆 㫅 㩷㪽 㪸 㪺 㫀㫃㫀㫋 㫐

Fig. 5 The flow of sludge dryness facility at HW.
The steam (6t/h) used for drying, which is the surplus steam generated at the adjacent HIF,
dehydrates 75% moisture sludge to 40%. The dried pellet is 3cm in diameter and 10cm long. The
pellet burns efficiently at the incineration facilities and does not fall out of stoker. In this drying
process, original sludge in 75% moisture is mixed with 20% moisture sludge in the drier, and the
mixture then turns into 40% sludge. The offensive odour emitted from the sewage sludge is an issueof this drying process, so this plant has three resolutions for deodorization of sludge.
Refuse incineration and Super power generation system- 204 -

Utilization of sewage sludge in Kitakyushu City of Japan

5

Next, we describe super power generation system (SPGS) which is adopted at KIF. The SPGS uses
gas turbine together with steam turbine. As shown in Figure 6, 7 the steam of the refuse incineration
boilers is reheated by high temperature exhaust gas from gas turbine, which is placed in the former
steps of the steam turbine and consumes city gas as fuel. Reheated steam reaches the hightemperature at 370 degrees C and the high pressure at 38 atmospheres absolute. Thus, thiscombined system, steam turbine and gas turbine, achieves 26% power generation efficiency.
Through this system much more electricity can be obtained than conventional systems. This
combined system is a maximum scale in Japan.
㪩 㪼㪽㫌㫊㪼 㩷㪛 㫉㫐㩷㫊㫃㫌㪻 㪾㪼㪙 㫆㫀㫃㪼㫉㩷㪟 㫆 㫇 㫇 㪼㫉㩷㪙 㪸㪾㩷㪽㫀㫃㫋㪼㫉㪪㫋㪸㪺㫂㩷㪩 㪼㪽㫌㫊㪼 㩷㫇 㫀㫋㪨㫌㪼㫅㪺㪿㩷㫉㪼㪸㪺㫋㫆㫉㪪 㫋㪼 㪸㫄 㩷㫊㫌㫇 㪼㫉㩷㪿 㪼㪸㫋㪼㫉㪠㫅㪺 㫀㫅 㪼㫉㪸 㫋㫆 㫉㩷㪜㪺㫆㫅㫆㫄㫀㫑㪼㫉㩷 㪪㫌㫇㪼㫉㩷㪿㪼㪸㫋㪼㫉㪟 㫆 㫋㩷㫊㫇 㫉㫀㫅㪾㩷㪽㪸 㪺㫀㫃㫀㫋㫐㪚 㫀㫋㫐㩷㩷㪾㪸㫊㪞 㪼 㫅 㪼㫉㪸㫋㫆㫉㩷㪞 㪸㫊㩷㫋㫌 㫉㪹 㫀㫅㪼㩷㪪 㫋㪼 㪸㫄 㩷㫋㫌 㫉㪹 㫀㫅㪼㪠㫅 㪿㫆 㫌 㫊㪼 㩷㫊㫋㪼㪸 㫄㪞 㪼㫅 㪼 㫉㪸㫋㫆 㫉㩷㪚 㫆 㫅 㪻 㪼 㫅㫊㪼 㫉㩷㪚 㫆㫆 㫃㫀㫅 㪾㩷㩷㩷㫋㫆 㫎 㪼㫉㪪 㫋㪼㪸㫄 㩷㩷㪽㫃㫆 㫎㪠㫅㪺 㫀㫅㪸 㫃㪸㫋㫀㫆 㫅㩷㩷㪺㪸㫇 㪸㪺 㫀㫋㫐㩷㩷㩷㩷㪏㪈 㪇㩷㩷䌴㪆 ᣣ㪞 㪼 㫅㪼 㫉㪸㫋㫀㫆㫅 㩷㪺 㪸㫇 㪸㪺㫀㫋㫐 㩷㩷㩷㪊㪍䋬 㪊㪇 㪇㪢 㪮䋨㪪 㫋㪼㪸㫄 㩷㫋㫌 㫉㪹 㫀㫅㪼㩷㩷㩷㩷㩷㩷㩷㪉㪏䋬 㪊 㪇㪇 㪢 㪮 䋩䋨㪞 㪸㫊㩷㫋㫌㫉㪹 㫀㫅 㪼㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪏 䋬 㪇㪇 㪇㪢 㪮 䋩㪞 㪸㫊㩷㩷㪽㫃㫆㫎㪮 㪸 㫋㪼㫉㩷㩷㪽㫃㫆㫎㪚 㫆 㫆 㫃㫀㫅㪾㩷㫎 㪸㫋㪼 㫉㩷㪽㫃㫆 㫎㪚 㫆㫅 㪻 㪼 㫅㫊㪸 㫋㪼㩷㫋㪸㫅 㫂㪚 㫀㫋㫐㩷㩷㪾㪸㫊

Fig. 6

Power generation flow diagram of the Kougasaki incineration facilityS
S uu pp ee rr
G ee nn ee rr aa tt ii oo nn
SS yy ss tt ee m
m

2 6 䋦
䋦

E f f ii cc i e n c yy
II nn cc ii nn ee rr aa tt oo rr

SS tt ee aa mm

2
2 8 0 㷄TT oo w
w nn
G
G aa ss

5
5 3 0 㷄2 8 0 㷄H
H ee aa tt EE xx cc hh aa nn gg eeG
G aa ssG
G aa ss TT uu rr bb ii nn ee

88 ,, 00 0
0 00 kk ww

3 7 0 㷄SS tt ee aa mm

TT uu rr bb iinn ee

22 3
3 ,, 00 00 00 kk ww

2
2 88 ,, 33 0
0 0
0 kk ww

TT oo tt aa ll

3
3 6
6 ,, 33 00 00 kk ww

Fig. 7 Super power generation system (SPGS)At present, one of three refuse incineration facilities in Kitakyushu City is under reconstruction to
introduce gasification melting furnace (the Moji incineration facility shown in Fig. 8). The power
generation efficiency of this facility is 20%, and it is 10% higher than HIF or conventional ones. In
order to achieve higher power generation efficiency, we expect to use this new facility instead oflow efficiency facility in HIF.

- 205 -

6

Utilization of sewage sludge in Kitakyushu City of JapanG a s ific a t io n M e lt in g F u r n a c e
W
W aa ss tt ee

CC oo kk ee (( 55 %% oo ff w
w aa ss tt ee ))S
S tt ee aa mm
LL iimm ee ss tt oo nn ee (( 44 %% oo ff w
w aa ss tt ee ))TT uu rr bb ii nn ee,, CC OH
H 22 OO 55 00 %%O 11 55 %%CC O
O 22 11 55 %% ,, CC H
H 44 ++ ,,H
H 22 22 00 %%G
G aa ss ii ff ii cc aa tt ii oo nn
33 00 00 㷄㷄~~
11 00 00 00 㷄㷄M
M ee ll tt ii nn gg
11 88 00 00 㷄
㷄

1 1 0 0 㷄CC oo mm bb uu ss tt ii bb ll ee
gg aa ssM
% oo ff w
w aa ss tt ee ))M ee lltt iinn gg A
A ss hh (( 11 00 %M
% oo ff w
w aa ss tt ee ))M ee lltt iinn gg M
M ee tt aa ll (( 33 %B
B oo ii ll ee rr

Fig. 8 Gasification melting furnace power generation at new Moji incineration facility(4) Cement materialization system
The system of cement materialization of DS in Kitakyushu city has following features.
䊶㩷 Because we directly supply the DS into a cement manufacturing process, everything can beeffectively utilized as cement materials. Thus, it does not waste any DS. Moreover, theorganic matter included is used as substitution of calcinations fuel.
䊶 Since the DS is thrown in a kiln at a temperature of 1,500 degrees C, it is decomposedcompletely. Thus, no odour emission occurs.
䊶㩷 Cement materialization business in a scale of 40,000t DS per year is at the national maximum
level.
䊶㩷 Since one of the private sector’s cement factories is adjacent to Kougaki WWTP, the cost forsludge transportation is low.
Since the limited number of cement companies accepts our sludge, there is no competition incontract. Therefore, we do not have space to quickly response to needs of the present times such as
converting to new systems, although the CMS mentioned above has advantages. This is our subject.
Measures of sludge treatment in the future(1) Subjects on future DS treatment in Kitakyushu city
The following are subjects on DS treatment in Kitakyushu city in coming years.
Correspondence to social situation changes like global warming prevention etc.
From now on, the use of the renewable energy that does not rely on fossil fuel will be further
advanced at a worldwide level as promoted by "Kyoto Protocol". Focusing on the sewage sludge,
the organic matter in the sludge is assumed to be biomass 100 percent renewable energy. So now
we are facing an important transitional period from waste to the valuable thing regarding sewage
sludge. Based on this realization, we should take the most appropriate measures for next-generation
method for the sewage sludge treatment in Kitakyushu city.
Regarding the reduction of sludge processing expense.

- 206 -

Utilization of sewage sludge in Kitakyushu City of Japan7

For further utilization of sewage sludge as useful resources, we want to select and introduce
methods that cost us the least.
Agreement limit for cement materialization
Present agreement term with the private sector for the materialization is going to expire in 2009.
Although it is possible to continue the agreement, we might have to concern about unfavourable
sludge acceptance price.
The sludge drier’s standard life to 2009
The Hiagari sludge drier was built in 1999 and has been operating for 7 years. The standard life thecentral government defines is ten years, so the sludge drier will reach the maturity date in three
years. If we continuously use the facility after the standard life passes, we must make overall
judgment for the maintenance and repairs.
(2) Direction and note in the future sludge treatment
Sewage sludge treatment adviser committee
This city set up "Sewage sludge treatment adviser committee" in August, 2005 by the specialists
who belong to universities and a laboratory in the country based on the subjects mentioned above to
make use of the sewage sludge as a valuable resource, and to examine a suitable processing method
for this city from the viewpoint of reducing the environmental burden of the city. We will do theoverall evaluation from the views on an economy, energy consumption, and an environmental
aspect, etc. by the end of this fiscal year, and bring the investigation results.
Sludge fuelization
There are several methods of sludge fuelization. Adopting new method, duration of practical use,energy consumption efficiency, global warming prevention as well as economies should be
evaluated. So-called dryness, dry granulation and carbonization methods have been practically used
inside and outside the country, though some subjects still remain unsolved in other methods. Mostof sludge fuelizing methods consume some kind of fuel through a dry process and the carbonization
process, etc. in order to create a new fuel. In other words, the fuel used is converted to the biomass
fuel. Supposed we do most efficient processing, energy yield by the conversion is 1.5 times energyof the fuel consumption. We should select the processing method and scale considering thesethings.
Sludge Fuelization verification test
At the Kitaminato WWTP, sludge fuelizing field test has been started since this march. This test
employs the Dry Granulation Method. In this method, exhaust gas that comes from the burning offuel is directly brown against the dry dram with paddles. This method is expected to have high dry
efficiency and possible to obtain dry grain in ball with nearly 8 % moisture which has about
17Mj/kg in lower calorific value. So this grain could be an alternative energy source of coal whichis consumed at power plants. We will continue this verification test until next march and make acomprehensive assessment on technical reliability, financial aspect, and heat balance and so on.
(This test is carried out by Japan Sewage Works Agency and Nippon Steel Corporation.)
Overhaul of dewatered sludge treatment system- 207 -

8

Utilization of sewage sludge in Kitakyushu City of Japan

During the overhaul of the sludge dryer, sludge is treated in the cement facility. The cost fortreatment is included in the present contract. The cement factory has the treatment capacity for thesludge and is always ready to receive the sludge. Considering the future, it will become an
important point to secure a way for overhaul. It is difficult to store DS temporally in the process ofthe sludge treatment because of the odour issue. Kitakyushu City has three refuse incineration
facilities, and each has capacity to stock 10 days or more volume of refuse in pit. In addition, total
incineration capacity makes one month overhaul of each facility alternately in a year. So
considering it, at least three ways might be required to secure the DS treatment in our city.
Bad odour control measures
As mentioned above, drier has two high and one low deodorizer at present. One of high deodorizers
was additionally introduced after the construction because people who live in the vicinity of theplant often complained about the bad odour from the drier. In spite of this improvement, even now
some complaint is reported from the neighbourhood. For the construction of fuelization facility inthe centre of highly populated cities, we need to think about how we can prevent possible odour
issue.
Conclusions
Kitakyushu City proclaimed “A grand design aiming at World Capital of Sustainable Development”
in 2004 in which we have 10 basic philosophies. Of those philosophies, reduction of environmental
burden, CO2 emission, water and air contamination and others, on our region and earth is included.
In adherence with the spirit of it, we consider introducing next generation’s sludge treatment
method from the following perspectives.
・Realizing “uniqueness of Kitakyushu city”
・Fuelizing biosolids sludge
・Emphasizing effective and efficient system in energy consumption and CO2 emission.
Kitakyushu city experienced severe environmental pollution in 1950s and 60s and finally overcame
it through citizen’s movement and cooperation between people, corporations and our government.
In this respect spread of sewerage in our city played an important role of the improvement of theenvironmental situations. Thorough sewage works, we will continue making contributions in apositive manner to resolving local and global environmental problems and fulfil our responsibility
as a world citizen in the future.

- 208 -

- 209 -Sea reclamation

Past
・sea reclamation（～1998）・sea dumping（～1999）London Treaty revision enacted in 1996

Sea dumping

Treatment of sewage sludge （Past）

Construction Bureau
Sewer Systems Administration Department

Utilization of sewage sludge
in Kitakyushu City of Japan

1977 78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99 2000 01

02

03

04

Sea dumping ⑤

Sludge incineration

Past
・sea reclamation（～1998）・sea dumping（～1999）

Cement materialization

present
・cement materialization（1997～）
・sludge incineration withrefuse（1999～）

Treatment of sewage sludge （Present）

Refuse In． ④

20,00010,000Cement ③

40,00020,000

Sea reclamation ②

60,00030,000Landfill ①

80,00040,0000100,000

50,0000120,000

60,000London Treaty revision enacted in 1996④㎥
140,000 ⑤

160,000

70,000t①

180,000

80,000200,000

90,000100,000

Transition of the amount of sewage
sludge and treatment～

110t/d

1,100℃

Rotary kiln

Preheater

Clinker Cooler

1,450℃- 210 -

5,100t/ year

facility

Cement10km

km

Distance

10km⇒ Cement Fa.
(Kanda)Sone WWTP⇒ Hiagari drier

Shinmachi WWTP

⇒ Hiagari drier

Hiagari WWTP

⇒ Hiagari I F (0.1km)⇒ Kougasaki I F(25km)

Hiagari dry facility

S t e a m f lo w

Kanda facility

W a t e r f lo w

G a s f lo w

S lu d g e f lo w

S te a m h e ad e r

158℃

6kg/cm2

D r ie d s lu d g e f e e d e r

S lu d g e d r y e rＰＰIn c in a la t io n
f a c ilit y

E a c h d e v ic e

D ir e c t ly b u r n n in g
fu rn a c e
D e o d o r iz e da ir p r e h e a t e r

F o r m m a k in g
m a c h in e

M ix in g d e v ic e

C o n stan tv o lu m e
fe e d e r

ＰS lu d g e p u m p t o m ix e r

C o n d e n s a teta n kD r y a ir
p re h e a te nＰ

C o n s ta n t fe e d e r（ h ig h m o is t u r e ）C o n s ta n t fe e d e r（ lo w m o is t u r e ）ＰS lu d g e c a k e

S lu d g e c a k e

T h e rm a ls to ra g e
d e o d o r iz a t io n
fu rn a c e

F o rm m a k e dcake hopper

The flow of sludge dryness facility at HW

In c in a la t io n
f a c ilit y

1km⇒ Cement Fa.
(Kurosaki)⇒ Hiagari drier

Kitaminato WWTP

Kougasaki WWTP

10km

Present state ofsludge treatment

Cement company

7,200t/year

8,200t/year

10.7Km

17.6t/daytreatment
25.1t/daySone

facility

5,800t/yaer

17.8t/day

9,600t/year

26.4t/day

Hiagari

19.0Kmtreatment

0.1Km

Shinmachi

9.5Km

22,900t/year

62.8t/dayDryertreatment

HiagariSludge10.9KmIncinalation with refuse

Dry Treatment

Cement Material

15.7ｔ/day

Kougasaki

24.7KmKurosaki facility

Cement company

1.2 Kmtreatment

Kougasaki

treatment

7,600t/year

33,700t/year

Kitaminato

20.8t/day

92.4t/day

Destination of dewatered sludge

SludgeCray, Lime

Cement Material Process

Stack

Dehumidifier- 211 -Steam
TurbineGas
Turbine

L.N.G.

270℃

28,300kw(23,000kw)

370℃

8,000kw

530℃

Steam 24kg/cm2

Stack

280℃ 90℃

Total Efficiency 26%

Super Electric Power Generation System in Kougasaki

Incinerator

Waste

40t/d

RefuseDrysludgePower generation flow diagram of theKougasaki incineration facility

600t/dRefuseincinaration

HopperDS dry facility

Hiagari Refuse incinaration facility

6,000kW

steam

steam

Form
makingmachineSteam dram

Steam drier
(75%
40%)

electricity

120t/dSteam turbine
generator

SludgeHiagari WWTP

Energy recycle system ofsludge incineration with refuse

Refuse genera tion
( 6,000kW )T otal in cin ar ated vo lum e
1 70,000 to n per ye ar

WWTP

Sale 2,0 00MW h

21 ,00 0MWh

In cin aration fac.

18 ,00 0MWh
( 7 ,00 0t-C O 2)
Total elect ric it y
41,000M Wh

G
G aass

8 ,0 0 0
w
0 kkw

S
Ste
teaam
m

280℃

S uuppeerr
G e n e ra tio n
S yy s te m

28
8 ,3
, 3 0 0 kkww

2 3 ,,000
00
0 kkww

T o t a ll

3 6 ,3 0
00
0k w
w

370℃

H e a tt E xxcch
h aan g
ge

280℃

SSte
teaam
m TTuurb
r bin
inee

530℃

G
b in
G aass TTu
urrb
in ee

Tow n
G
G aa sInn c in e r a tto
or

E ffic ie n c y 2 6 ％Super power generation system

Non-b io so lids
(plastic andoth ers)

6,50 0t i ncluded

Dry slud ge

Biosolid s

Hiagari incineration facility’s fuel for
power and electricity distribution

- 212 -Steam

KogasakiM
M ee lt
ltin
in g
g
1
18
80
00
0℃
℃

G
G aa ss if
ific
ic aa ttio
io n
n
3
30
00
0℃
℃
~
~
1
10
00
00
0℃
℃

C
Co
om
mb
bu
u ss ttib
ib le
le
g
g aa ss

T u r b in e

B
Bo
o ile
ile rr

1100℃

H
H 22O
O 5
50
0%
% ,, C
CO
O 1
15
5%
%
C
CO
O 22 115
5%% ,, C
CH
H 44+
+ ,H
,H 22 220
0%%M
M ee lt
ltin
in gg A
A ssh
h ((1
10
0%
% oo ff w
w aa ssttee ))M
M ee lt
ltin
in gg MM eettaall ((33%% oo ff w
w aa ssttee ))W
W aa ss ttee

C
C oo kk ee ((55%% oo ff w
w aa ssttee ))S te a m
LL im
im ee ssttoo nn ee ((44%% oo ff w
w aassttee ))G a s if ic a t io n M e lt in g F u r n a c e

Gasification melting furnace power
generation at new Moji incineration
facilityNight Soil Office

Collection OfficeElectricity Sewerage Plant

Hot Spring

Electricity

Power Company

Utilization of Heat
+20,000,000yen+

Electricity

Incineration 22%

Steam

Heat Supply 1%+107,000,000yen

Power+1,163,000,000yen

Power company 71%

SewageTreatment7%

Power Generation 23,500kw（Hiagari 255℃、Kogasaki 370℃）

Steam Temperature 400℃

（Hiagari 20kg/cm2、Kogasaki 23kg/cm2）

Steam Pressure 40kg/cm2

High Efficiency (20%)
Generation

Steam turbine 84%

Incineration 15%

Ratio of steam consumption
in Kougasaki

- 213 -cost（million yen）

2002

215

incinaeration cost

（３６．１ th. t）

99

69

412

2003

233

93

65

456

38

inci. tans. cost

（４３．０ th. t）

382

inci.

（４１．２ th. t）

443

cement825 （８４．２ th. t）
31885

ce. material cost

（４１．２ th. t）

391

inci.

（４５．６ th. t）

494

cement（８６．８ th. t）※ Incineration cost raised in 2004 from 7,000 to 10,000 yen per ton）

drying cost

2001

175

314

（３０．２ th. t）

270（４５．０ th. t）

inci.

78

60

450

537

cementinci.

（４０．４ th. t）

463

cement87851 （８１．１ th. ｔ）（３８．３ th.t）Social changing

present
・cement materialization（1997～）
・sludge incineration
with refuse（1999～

global warming prevention

Biosolids use、New type of treatment（fuel alternative）

future483（３７．６ th. t）

337

inci.

（４４．９ th. t）

fiscal year

2005

168

120

48

449

cement820 （８２．５ th. t）
34

1999 Law concerning the Promotion of the Measures to Cope with
Global Warming
2000 Fundamental Law for Establishing a Sound Material-Cycle Society
2003 renewable portfolio standard
2004 “A grand design aiming at World Capital of Sustainable
Development” proclaimed
2005 Coming into effect of Kyoto Protocol

Global environment conservation

Past
・sea reclamation（～1998）・sea dumping（～1999）London Treaty revision enacted in 1996

329

inci.

（４４．４ th. t)

475

cementce. trans. cost

2004

172

106

51

444

31

804 （８２．７ th. t）

cement material cost supposed at 10,000
yen per ton

Transition of sewage sludge treatment

2000

178

100

0

56

36

404

59

733 （７０．６ th. ｔ）

200

300

400

500

600

700

800

900

Sewage sludge process cost transition■Sewage sludge treatment adviser
committee■Measures to be considered Drier Dry granulation
 High temperature carbonization
 Low temperature carbonization

Comparison of future sludge process
methods

environment like global warming
prevention
Reduction of sludge treatment costResponse to social changes on

Sludge Drier’s standard life（～2009 ）Agreement of cement material （～2009）

Subjects for dewatered sludge treatment

- 214 -





Odour
countermeasures to control bad odour
in urbanized plot----biological, activatedcarbon deodorizations and others

Overhaul
How to treat dewatered sludge during
overhaul of facilities

Note for decision of method

Sludge fuelization verification test (drygranulation method)

To adopt efficient system in energy
consumption and CO2 emission control
 To utilize sewage biosolid as a fuel
 To realize uniqueness of Kitakyushu cityObjectives

Moisture 8%, Reduction rate 1/5, 17Mj/kg

Produced sludge grain

- 215 -

Ａ－１

110

Ｂ－１

96

Ｂ－２

80

Ｂ－３

77

Ｃ－ １

115

PrerequisiteTransportation cost included
Overhaul term’s process cost included
Countermeasure cost against bad odour not included
There would be companies to be able to accept products created

0

50

100

150

200

Cost (Euro/ton)

Ｃ－ ２

110

Ｄ－ １

29

Mere result based on questionnaires
from makers and so unauthorized

Cost for future DS treatment in our city

2GTHQTOCPEGGXCNWCVKQPTGUGCTEJQPVGEJPQNQI[QHVJGUGYCIGUNWFIGFT[KPIWUKPICPQKNDCVJWPFGTFKOKPKUJGFRTGUUWTG
Fukuoka Prefectural Govement Department of Structures and Urban Planning
Division of Sewer Infrastructure
A Subsection Chief of Regional Sewerage System KAZUTAKA NOGAMI
SpeakerJapan Institute of Wastewater Engineering Technology (JIWET)
1st Research department Researcher SHIGERU IKARUGI +PVTQFWEVKQPIn Fukuoka Prefecture, effective use and the recycling of the sewage sludge were
examined in consideration of an increase of the amount of the sewage sludge
generation according to the progress of wastewater facilities. Stable disposal andthe global environment maintenance of the sewage sludge were done to theexamination by the purpose.
Then, Fukuoka Prefecture paid attention to the technology of the sewage sludge
drying using an oil bath under diminished pressure, and executed a joint researchof this technology with JIWET.
This technology dries the one that the dewatered sludge was mixed withcooking oil waste. This technology heats the sewage sludge below the atmosphericpressure, and manufactures dried sludge of about 3.0% of the rate of the include
water. The calorific value can be high because oil is contained, and this driedsludge is expected to be used effectively as associate Mo material in the cement
manufacturing and an alternate fuel such as coal.
The practical use research was done in 1996 fiscal year, and the design parameterof the real equipment was set. Equipment was constructed in 2002 fiscal year, andthe proof driving investigation was executed as a performance evaluation
research that had used equipment in 2003 fiscal year.
This time, the performance evaluation research is announced.

 6GEJPQNQIKECNQWVNKPG
 2TKPEKRNGQHFT[PGUU
Fig.1 shows the concept chart of the technology of sewage sludge drying using an
oil bath under diminished pressure.
1) The cooking oil waste is mixed with the dewatered sludge in device.
2) It decompresses to about -40kPa in device, and the compound of oil and sludge
is heated with steam. The cooking oil wastes plays heat transfer medium'srole, and evaporates moisture in dewatered sludge.
3) The amount of sludge loses weight to about 1/3. (Refer to Fig. 2)
1- 217 -

- Because it decompresses in the device, and the boiling point of water islowered to about 85͠, the deterioration of the cooking oil wastes can be
decreased, and oil is used repeatedly.
䋺Cooking oil wastes

Decompression

䋺Dry䇭Sorids
䋺WaterEvaporation water

Heat (steam)㽲 before drying

㽳 drying

㽴 after drying

Fig.1 Image of dry principle㪺㫆㫆㫂㫀㫅㪾㩷㫆㫀㫃㩷㫎㪸㫊㫋㪼㫊䋳䋵䋦㪤㫆㫀㫊㫋㫌㫉㪼
䋸䋰䋦䋶䋸㪤㫆㫀㫊㫋㫌㫉㪼
䋳䋦

䋱䋰䋰

䋱䋰䋰
㪛㫉㫐㩷㪪㫆㫃㫀㪻䋲䋰䋦㪛㫉㫐㩷㪪㫆㫃㫀㪻䋶䋳䋦㪛㪼㫎㪸㫋㪼㫉㪼㪻㫊㫃㫌㪻㪾㪼

㪛㫉㫀㪼㪻㩷㫊㫃㫌㪻㪾㪼䋳䋲

Fig.2 Volume reduction image of sewage sludge
 $CUKEHNQYQHVJKUGSWKROGPV
Fig.3 shows the flow of the system of this technology. The processing of thistechnology is a batch type, the ability to process the dewatered sludge of 10
ton-wet times is possessed, and the amount of dewatered sludge disposal each day
is 90t-wet/day.
2- 218 -

1) The dewatered sludge of 10 ton-wet and medium oil 7m3 are mixed in sludge
mixing tank, oil is distributed in dewatered sludge, and it turns it on to thesludge dryer through pre-heating tank.
2) It is decompressed to -40kPa in sludge dryer, and the dewatered sludge isheated, and moisture evaporates. The evaporating moisture becomescondensation water after it cools with the condenser via mist separator, and isprocessed as recycle flow water.
3) The compound of dried sludge and the medium oil is separated to dried sludge
and oil with oil separator. The separating oil is refined further with the oil
re-separation machine, and recycled as medium oil.
4) The dried sludge after oil is separated is cooled by the cooling machine and isdone to the dried sludge hopper.

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㽺

㽻

㪤㪸㫀㫅㩷㪹㫆㫀㫃㪼㫉㪚㫆㫅㪻㪼㫅㫊㪼㫉㪭㪸㪺㫌㫌㫄㩷㫇㫌㫄㫇㪽㫌㫉㫅㪸㪺㪼㩷㫋㫌㪹㫌㫃㪸㫉㩷㪹㫆㫀㫃㪼㫉㫉㪼㪻㫌㪺㪼㪻㩷㪸㫄㫆㫌㫅㫋㩷㫆㪽㪼㫍㪸㫇㫆㫉㪸㫋㫀㫆㫅㪑㩷㪈㪉㩷㫋㩷㪆㪿㫉㫄㫌㫃㫋㫀㫋㫌㪻㪼㩷㪿㪼㪸㫋㪼㫏㪺㪿㪸㫅㪾㪼㫉㩷㪿㪼㪸㫋㫀㫅㪾㫊㫌㫉㪽㪸㪺㪼㩷㪸㫉㪼㪸㪑㩷㪉㪌㪎䌭䋲㫎㪸㫋㪼㫉㩷㫁㪼㫋㩷㫋㫐㫇㪼㫉㪸㫋㪼㩷㫆㪽㩷㪼㫍㪸㪺㫌㪸㫋㫀㫆㫅㪑䋳㪐㪅㪎䌭 㪆㫄㫀㫅Fig.3 Plant equipment flow3
- 219 -

㪻㫀㫉㪼㪺㫋㩷㪹㫌㫉㫅㫀㫅㪾㩷㫎㫀㫋㪿㩷㪽㫌㪼㫃㪺㫆㫄㪹㫌㫊㫋㫀㫆㫅㩷㫉㪸㫋㪼㪑䋳㪋㪇㩷䌭 㪆㫄㫀㫅 %QPVGPVQHRGTHQTOCPEGGXCNWCVKQPTGUGCTEJ
&T[RGTHQTOCPEGA dry performance of this equipment is investigated. Tab.1 shows the dry
performance target of this research.

Tab.1 Dry performance target

Processing
condition

Quality ofdried sludge

Sludge of processed object

Digested sludge

Moisuture content㧔㧑㧕

80

Amount of processing of dewateredsludge㧔t-wet㧛batch㧕

10䇭㶎

Dry time 㧔min㧕

120

Mixture ratio of heat medium oil㧟㧔㨙 /t-wet㧕

0.6㨪0.8

Moisuture content㧔㧑㧕㻍3

Cooking oil waste content㧔㧑㧕

30㨪40

higher calorific value㧔kJ/kg-DS㧕㻍20,000

㶎䋮90䌴-wet䋯Day'EQPQO[The amount of the energy use of this equipment for the driving period is arranged,
and the utility cost and the administrative and maintenance cost per the turningon dewatered sludge are calculated.
 2QUUKDKNKV[QHGHHGEVKXGWUGHQTUGYCIGFTKGFUNWFIGProperties of the dried sludge manufactured from this equipment are comparedwith other biomasses, and best, effective use is examined.

4- 220 -

 4GUWNVQHRGTHQTOCPEGGXCNWCVKQPTGUGCTEJ
&T[RGTHQTOCPEGTab.2 shows the investigation result of every the season. Moreover, theaccumulation frequency is shown in Fig.4 about the water content of dried sludge
at each time. The water content of dried sludge falls below target value (3%), andcan produce dried sludge without trouble for change of the water content(79㨪
86%) of the dewatered sludge.
Tab.2 Dry performance result
Time

Investigation result
Investigation item

Apr-03

Sludge of processed object

Nov-03Jan-04

Digested sludge

Moisuture content㧔㧑㧕

Processing Amount of processing of dewateredsludge㧔t-wet㧛batch㧕
condition
Dry time 㧔min㧕

80㨪84

79㨪82

81㨪82

81㨪86

10

10

10

10

0.64㨪0.75 0.64㨪0.69 0.65㨪0.69 0.64㨪0.69

Mixture ratio of heat medium oil㧟㧔㨙 /t-wet㧕









Moisuture content㧔㧑㧕

0.9㨪4.2

0.5㨪1.5

0.5㨪1.5

0.4㨪1.7

Cooking oil waste content㧔㧑㧕

34

37

36

34

higher calorific value㧔kJ/kg-DS㧕䋭

20,000䋭㪉㪉㪃㪈㪇㪇

Quality ofdried
sludge⚥Ⓧ㗫ᐲ
Accumulation frequency

Aug-03













03
䂾䊶䊶䊶Apr -㧠᦬- 03䂓䊶䊶䊶Aug 㧤᦬- 03䂹䊶䊶䊶Nov ᦬
04䂥䊶䊶䊶Jan -㧝᦬㩷㪇㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪈㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪉㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪊㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪋㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪌㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪍







ᴤ᷷ੇ῎ᳪᵆ฽᳓₸
sludge Moisuture content㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷 Dried䋨䋦䋩
Fig.4 Accumulation frequency distribution of dried sludge moistureat the four seasons
5- 221 -

㪌㪇㩼୯
㪐㪇㩼୯
㪈㪅㪏
㪟㪈㪌㪅㪋
㪉㪅㪍
㪇㪅㪎
㪟㪈㪌㪅㪏
㪇㪅㪐
㪈㪅㪈
㪟㪈㪌㪅㪈㪈
㪈㪅㪋
㪈㪅㪉
㪟㪈㪍㪅㪈
㪈㪅㪌

'EQPQO[Tab.3 shows the trial calculation result of the cost of construction and integrated
maintenance cost necessary to process the dewatered sludge by 1ton-wet.
In Mikasagawa treatment center, a digestive gas of the sewage sludge origin isused as substitution of necessary kerosene for the heat source of dryness.
Therefore, the utility cost can be suppressed to low.
Cost to process
dewatered sludge by 1t-wet

Cost item

construction

Maintenancemanagement䎂㪆䌴㪄㫎㪼㫋

€㩷㪆䌴㪄㫎㪼㫋

Civil engineeringand construction¥1,069㪎㪅㪈㪎㩷͐

Plant machine¥8,725㪌㪏㪅㪌㪍㩷͐

Plant electrical¥1,379㪐㪅㪉㪍㩷͐

Subtotal Ԙ¥11,173㪎㪋㪅㪐㪐㩷͐

Utility¥4,350㪉㪐㪅㪈㪐㩷͐Labor¥2,224㪈㪋㪅㪐㪊㩷͐

Normal shutdown¥2,107

㪈㪋㪅㪈㪋㩷͐

Subtotal 㽳¥8,681㪌㪏㪅㪉㪍㩷͐¥19,854㪈㪊㪊㪅㪉㪌㩷͐

Integrated cost‫ޓ‬Ԙ㧗ԙ㶎䋮Equipment driving time 䋺 䋲䋴䌨䌲䋯Day
㶎䋮The equipment life 䋺 䋱䋰Years2QUUKDKNKV[QHGHHGEVKXGWUGHQTUGYCIGFTKGFUNWFIG %QORCTKUQPYKVJQVJGTDKQOCUUGU
Tab.4 shows the result of comparing other typical biomasses of the sewage
sludge system, the wood system, and the food waste system with driedsludge. The feature of dried sludge manufactured from this equipment isshown below.
٤ Because this dried sludge contains oil, higher calorific value is higher thanother biomasses. Moreover, higher calorific value for each supplied ash
content is higher than the carbonization sewage sludge when seeing in theindex of HCV/AC(3㨪10 times).
٤ This dried sludge is high organic, and meets a quality as the fertilizer and an

official standard of Japan concerning safety.
6- 222 -

Tab.4 Comparison with other biomasses
Analysis result
Biomass
Sewagesludge䌫㪡䋯㫂䌧㪄㪛㪪
Dried 䌳䌬䌵䌤䌧䌥㶎
Carbonization
sewage sludge

MoisutureAshcontent
content䌫㪺㪸㫃䋯㫂䌧㪄㪛㪪䋦䋦㪄㪛㪪

Higher calorific value㨪

㨪 㨪㪏㪃㪇㪇㪇䌾㪏㪃㪉㪇㪇 㪈㪃㪐㪈㪈䌾㪈㪃㪐㪌㪐%JNQTKPG
EQPVGPV㫄䌧䋯㫂䌧*%8㧛#%̪
㫂䌊䋯㫂䌧





㨪

䋭

㪎㪋䌾㪏㪌

䋭

㪐㪋䌾㪈㪈㪈

Carbonization
woods waste㪐㪃㪋㪍㪇䌾
㪈㪈㪃㪈㪊㪌

㪉㪃㪉㪍㪇䌾㪉㪃㪍㪍㪇䋭㪇㪅㪊䌾㪊㪅㪌

㪊㪐䌾㪈㪐㪇

㪉㪃㪎㪇㪊䌾
㪊㪎㪃㪈㪈㪎

Carbonization
construction waste㨪

㨪

㧙㨪 㨪㨪


Carbonization food waste㪈㪊㪃㪌㪉㪈䌾
㪈㪌㪃㪐㪐㪈

㪊㪃㪉㪊㪇䌾㪊㪃㪏㪉㪇䋭㪊㪏㪅㪈䌾㪋㪈㪅㪏㪈㪊㪃㪇㪇㪇䌾
㪈㪎㪃㪇㪇㪇

㪊㪉㪊䌾㪋㪉㪇

Coal (reference value)

26,000

6,211

9.05

20

䋭

1,300

Wood
waste

㶎䋮HCV䋯AC 䋺䇭Higher calorific value䋯Ash content
㶎䋮Dried sludge 䋺䇭Sewage sludge processed by sludge drying using a oil bath under diminished pressure 'HHGEVQHJGCVVTCRRKPIICUTGFWEVKQPAt first, the profit use as a biomass fuel has been paid to attention as for the
research beginning in recent years though this dried sludge put use in the
cement manufacturing process as associate Mo material in view.
Therefore, the effect of the reduction of the heat-trapping gas of threemethods (the green farmland use, the alternative fossil fuel use, and thecement raw material and supplementary fuel use) was provisionallycalculated. Fig.5 shows the trial calculation result.
 The amount of the exhaust reduction is a little because the heat-trapping gas
٤of about 11ton-CO2/ day is generated to manufacture dried sludge at thegreen farmland use, and the amount of the exhaust increases.
٤ The amount of the reduction is large because it is assumed the substitution of
the resource with large amount of the heat-trapping gas exhaust such as thefossil fuels if it uses it as the alternative fossil fuel use, and cement raw
material and supplementary fuel use. Therefore, the amount of theheat-trapping gas reduction exceeds the amount of the heat-trapping gas
exhaust when driving and constructing it. (Reduce by the alternative fossil
fuel use during 45ton-CO2/day. Reduce by the cement raw material andsupplementary fuel use during 36ton-CO2/day.) However, because the amountof the heat-trapping gas exhaust according to manufacturing dried sludge
increases when a digestive gas is not used, the effect of the reduction becomes
small. Therefore, effective use for a digestive gas is important to enable theeffect of the reduction of a bigger heat-trapping gas.

7
- 223 -

㪍㪇㪅㪇
㪌㪈㪅㪍
㪌㪇㪅㪇
㪋㪉㪅㪎

䌴㪄䌃䌏 䋲 䋯㪛㪸䌹





























㪋㪇㪅㪇
㪊㪇㪅㪇
㪉㪇㪅㪇
㪈㪇㪅㪇

㪍㪅㪍

㪍㪅㪍

㪍㪅㪍

㪉㪅㪌
㪇㪅㪇

#NVGTPCVKXGHQUUKNHWGN)TGGPHCTONCPF%GOGPVTCYOCVGTKCNCPFUWRRNGOGPVCT[HWGN

㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪼㫏㪿㪸㫌㫊㫋㩷㫉㪼㪻㫌㪺㫋㫀㫆㫅㩷㪹㫐㩷㪼㪽㪽㪼㪺㫋㫀㫍㪼㩷㫌㫊㪼㩷㽲㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪼㫏㪿㪸㫌㫊㫋㩷㪸㪺㪺㫆㫉㪻㫀㫅㪾㩷㫋㫆㩷㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪻㫉㫀㫍㫀㫅㪾㪃㩷㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪺㫆㫅㫊㫋㫉㫌㪺㫋㫀㫆㫅㪃㩷㪸㫅㪻㩷㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪸㪹㪸㫅㪻㫆㫅㫄㪼㫅㫋㽳㪜㪽㪽㪼㪺㫋㫀㫍㪼㩷㫌㫊㪸㪾㪼㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪿㪼㪸㫋㪄㫋㫉㪸㫇㫇㫀㫅㪾㩷㪾㪸㫊䋨䌴㪄㪚㪦䋲䋯ᣣ䋩㪞㫉㪼㪼㫅㩷㪽㪸㫉㫄㫃㪸㫅㪻㩷㫌㫊㪼㪘㫃㫋㪼㫉㫅㪸㫋㫀㫍㪼㩷㪽㫆㫊㫊㫀㫃 㪚㪼㫄㪼㫅㫋㩷㫉㪸㫎㩷㫄㪸㫋㪼㫉㫀㪸㫃㪸㫅㪻㩷㫊㫌㫇㫇㫃㪼㫄㪼㫅㫋㪸㫉㫐㩷㪽㫌㪼㫃㩷㫌㫊㪼㪽㫌㪼㫃㩷㫌㫊㪼

㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪼㫏㪿㪸㫌㫊㫋㩷㫉㪼㪻㫌㪺㫋㫀㫆㫅㩷㪹㫐㩷㪼㪽㪽㪼㪺㫋㫀㫍㪼㩷㫌㫊㪼㩷㽲

㪉㪅㪌

㪌㪈㪅㪍

㪋㪉㪅㪎

㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪼㫏㪿㪸㫌㫊㫋㩷㪸㪺㪺㫆㫉㪻㫀㫅㪾㩷㫋㫆㩷㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪻㫉㫀㫍㫀㫅㪾㪃㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪺㫆㫅㫊㫋㫉㫌㪺㫋㫀㫆㫅㪃㩷㪸㫅㪻㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪸㪹㪸㫅㪻㫆㫅㫄㪼㫅㫋㽳

㪍㪅㪍

㪍㪅㪍

㪍㪅㪍

㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㫀㫅㫋㪼㪾㫉㪸㫋㪼㪻㩷㪿㪼㪸㫋㪄㫋㫉㪸㫇㫇㫀㫅㪾㪾㪸㫊㩷㪼㫏㪿㪸㫌㫊㫋䋨㽳䋭㽲䋩

㪋㪅㪈

㪄㪋㪌㪅㪇

㪄㪊㪍㪅㪈

Fig.5 Effect of heat-trapping gas reduction

 5WOOCT[QHRGTHQTOCPEGGXCNWCVKQPTGUGCTEJ
To achieve the heat-trapping gas reduction target of Japan in the Kyoto Protocol*,energy conservation, new energy, and the progress of other reduction strategies
are needed more than before. Then, to achieve the target, the RPS law * wasenforced in Japan. The RPS law is a content in the law enforced aiming at the newenergy spread in 2003 that obligates more than a constant ratio to be used against
an electric entrepreneur as for the electricity obtained from new energy etc.
Especially, the amount of the introduction of crude oil conversion 19,100M liter is
expected about new energy in fiscal year 2010. (integrated resource energy
investigation committee report in July, 2001)㨫
New energy etc. that become objects are a photovoltaic generations, wind power8- 224 -

generation, biomass power generations, small-scale hydro-power, and thegeothermal power generations. This dried sludge is a biomass with the usage tomany fields like a green farmland, thermal energy, and the cement raw material
and associate Mo material, etc. as well as other biomasses. Especially, because thecooking oil waste (medium oil) is contained, calorific values are higher than otherbiomasses. Moreover, the mineral is few. Because it is a carbon neutral, thereduction in the amount of the heat-trapping gas exhaust can be expected.
Therefore, it is a biotechnology solid fuel excellent as the substitution of the fossil
fuel. The above-mentioned background exists, and attention is paid to this driedsludge by the electric power entrepreneur. Power generation that uses the fuelthat mixes coal with this dried sludge in Matsuura coal-fired power station(J-POWER) is done now. The mixture ratio of this dried sludge to coal is 1%, andpower generation is done without trouble. Two equipment of output 1,000MW is
set up in the Matsuura coal-fired power station, and consumption is about 4.4
million tons a year. Therefore, this approach has reduced the consumption of thecoal of about 44,000 tons a year. That is, the heat-trapping gas of about 110,000
tons a year will have been reduced. (Conversion value of CO2)
There is a big role that wastewater facilities are a hydrologic cycle. Wastewater
facilities in addition to the role is expected to reduce sewage sludge collected fromeach home to the society as a biomass energy resource.
It is expected that this research can contribute to the effective profit use of the
sewage sludge.
̪ Kyoto Protocol(Kyoto Protocol to the United Nations Framework Convention on
Climate Change): The Kyoto Protocol is a protocol resolved in Kyoto Conference on

Climate Change (the 3rd Framework Convention on Climate Change Conference of
the Parties and COP3) opened in Kyoto City (Japan) in 1997 based on Framework
Convention on Climate Change.

̪RPS law(Renewable Portfolio Standard law) : In the law enforced aiming at the
new energy spread in 2003, it is a content that obligates more than a constant ratio to
be used against an electric entrepreneur as for the electricity obtained from newenergy etc.

9- 225 -

- 226 -

1/22

3/22

The technology of sewage sludge drying
using an oil bath under diminished pressure䂾 Possibility of Stable sludge disposal䂾 Possibility of recycling sewage sludge
䂾 Contribution to global environment(2) BackgroundExamination problem in Fukuoka Prefecture
An increase of the amount of the sewage
sludge generation according to the progressof wastewater facilities

1.Introduction

1st Research Department
Researcher SHIGERU IKARUGIJapan Institute of Wastewater
Engineering Technology

Performance evaluation researchon technology of the sewage
sludge drying using an oil bathunder diminished pressureTokyo

Fukuoka
Prefecture

2/22

Fukuoka
Prefecture
4/22

The technology of sewage sludge drying
using an oil bath under diminished pressure

in MIKASAGAWA treatment center

Kyoto

٨

㻍㪎㪇㩼

Start of a joint research

1.Introduction

٨

Osaka

٨
䃂

㻍㪌㪃㪇㪌㪇㪃㪇㪇㪇㪧㫆㫇㫌㫃㪸㫋㫀㫆㫅㪧㪼㫉㪺㪼㫅㫋㪸㪾㪼㩷㫆㪽㫊㪼㫎㪼㫉㪼㪻㩷㫇㫆㫇㫌㫃㪸㫋㫀㫆㫅

Fukuoka Prefecture data

(1) Fukuoka Prefecture position

1.Introduction

- 227 -㻍100䌭㪛㫉㫐㩷㪪㫆㫃㫀㪻䋶䋳䋦㪛㫉㫀㪼㪻㩷㫊㫃㫌㪻㪾㪼㪛㫉㫐㩷㪪㫆㫃㫀㪻䋲䋰䋦㪛㪼㫎㪸㫋㪼㫉㪼㪻㫊㫃㫌㪻㪾㪼

䋱䋰䋰㪤㫆㫀㫊㫋㫌㫉㪼
䋳䋦

䋳䋲

䋶䋸

Fig.2 Volume reduction image of sewage sludge䋱䋰䋰㪤㫆㫀㫊㫋㫌㫉㪼
䋸䋰䋦㪺㫆㫆㫂㫀㫅㪾㩷㫆㫀㫃㩷㫎㪸㫊㫋㪼㫊䋳䋵䋦(2) Volume reduction image

2.Technological outline

7/22

5/22

㫊㫀㫅㪺㪼㩷㪈㪐㪎㪌㪈㪏㪅㪈㪿㪸

㪣㫆㫋㩷㪸㫉㪼㪸
㪬㫊㪼㩷㪹㪼㪾㫀㫅㫅㫀㫅㪾㪉㪐㪌㪃㪇㪇㪇㫄㪊㪆㪛㪸㫐㻍㪎㪇㪇㪃㪇㪇㪇

㪪㪼㫎㪼㫉㪼㪻㩷㫇㫆㫇㫌㫃㪸㫋㫀㫆㫅㫀㫅㩷㫋㫉㪼㪸㫋㫄㪼㫅㫋㩷㪸㫉㪼㪸㪘㫄㫆㫌㫅㫋㩷㫆㪽㫎㪸㫊㫋㪼㫎㪸㫋㪼㫉㩷㫀㫅㪽㫃㫌㪼㫅㫋

Fig MIKASAGAWA treatment center

Sludge treatment area

Wastewater treatment area㽳 drying

Evaporation water㽲㪪㫃㫌㪻㪾㪼㩷㫄㫀㫏㫀㫅㪾㫋㪸㫅㫂㽷㪛㫉㫀㪼㪻㩷㫊㫃㫌㪻㪾㪼㪿㫆㫇㫇㪼㫉

㽸

㽵

㽶

㽻

䃂

㽷

㽺
㪚㫆㫅㪻㪼㫅㫊㪼㫉㽹㪤㪸㫀㫅㩷㪹㫆㫀㫃㪼㫉㪪㫃㫌㪻㪾㪼㩷㪻㫉㫐㪼㫉㽴㪭㪸㪺㫌㫌㫄㩷㫇㫌㫄㫇㽵㪦㫀㫃㩷㫊㪼㫇㪸㫉㪸㫋㫆㫉㩿㫋㪿㪼㩷㪈㫊㫋㩷㫊㫋㪸㪾㪼㪀
㽻

䃂

6/22

8/22

㽶
㪦㫀㫃㩷㫊㪼㫇㪸㫉㪸㫋㫆㫉㩿㫋㪿㪼㩷㪉㫅㪻㩷㫊㫋㪸㪾㪼㪀㽼㪺㫆㫄㪹㫌㫊㫋㫀㫆㫅㪽㫌㫉㫅㪸㪺㪼

㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪺㫆㫆㫂㫀㫅㪾㩷㫆㫀㫃㩷㫎㪸㫊㫋㪼㫊䇭㫃㫀㫅㪼㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㫊㫋㪼㪸㫄䇭㫃㫀㫅㪼㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪼㫍㪸㫇㫆㫉㪸㫋㫀㫆㫅㩷㫄㫆㫀㫊㫋㫌㫉㪼㩷㪸㫅㪻㩷㪻㫉㫐㩷㪼㫏㪿㪸㫌㫊㫋㩷㫃㫀㫅㪼㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㫊㫃㫌㪻㪾㪼䇭㫃㫀㫅㪼

㽴

㽺

㽼

Fig.3 Plant equipment flow㽳㪧㫉㪼㪄㪿㪼㪸㫋㫀㫅㪾㫋㪸㫅㫂㽸㪦㫀㫃㩷㫊㫋㫆㫉㪸㪾㪼
㫋㪸㫅㫂

㽳

㽹

(3) Basic flow of this equipment

2.Technological outline

㽲㽴 after drying

Heat (steam)- 40䌫Pa

Decompression

Fig.1 Image of dry principle

㽲 before drying

䋺Water䋺Dry䇭Sorids

䋺Cooking oil(1) Principle of dryness

2.Technological outline

- 228 -㫆㫀㫃㩷㪹㪸㫋㪿㩷㪼㫍㪸㫇㫆㫉㪸㫋㫀㫆㫅㫌㫅㪻㪼㫉㩷㪻㫀㫄㫀㫅㫀㫊㪿㪼㪻㩷㫇㫉㪼㫊㫊㫌㫉㪼㪈㪐㪏䌭䋲㪛㫀㪾㪼㫊㫋㪼㪻㩷㪻㪼㫎㪸㫋㪼㫉㪼㪻㫊㫃㫌㪻㪾㪼
㪐㪇㫋㫆㫅㪄㫎㪼㫋㩷㪆㩷㪛㪸㫐㩿㪈㪇㫋㪄㫎㪼㫋㩷㪆㩷㪹㪸㫋㪺㪿㪀㪉㪋㪿㫉㩷㪆㩷㪛㪸㫐㩿㪐㪹㪸㫋㪺㪿㩷㪆㩷㪛㪸㫐㪀㪟㪼㪸㫋㫀㫅㪾㩷㫊㫌㫉㪽㪸㪺㪼㩷㪸㫉㪼㪸㪧㫉㫆㪺㪼㫊㫊㫀㫅㪾㩷㫆㪹㫁㪼㪺㫋㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㫇㫉㫆㪺㪼㫊㫊㫀㫅㪾㪛㫉㫀㫍㫀㫅㪾㩷㫋㫀㫄㪼Spec
㪤㫆㪻㪼㫃㩷㫆㪽㩷㪻㫉㫐㪼㫉

3.3 Possibility of effective use

3.2 Economy

3.1 Dry performance

11/22

Moisuture content㧔㧑㧕㻍20,000

higher calorific value㧔kJ/kg-DS㧕

㻍3

Moisuture content㧔㧑㧕30㨪40

0.6㨪0.8

Cooking oil waste content㧔㧑㧕

120

Dry time 㧔min㧕

10䇭㶎

80

Digested sludge

Mixture ratio of heat medium oil㧟㧔㨙 /t-wet㧕

Amount of processing of dewateredsludge㧔t-wet㧛batch㧕

㶎.90ton-wet/Day

Quality ofdried sludge

Processing
condition

Sludge of processed object

Tab.1 Dry performance target

12/22

3. Performance evaluation research Content

3. Performance evaluation research Content

3.1 Dry performance

10/22

㻍20,000

30㨪40

㻍3

Quality of dried sludge

Moisuture content
㧔㧑㧕Cooking oil waste
content㧔㧑㧕higher calorific value
㧔kJ/kg-DS㧕

Fig. Dried sludge

2.Technological outline

9/22

Fig. Sludge dryer

2.Technological outline

13/22













㪌㪇㩼୯
▸࿐
㪐㪇㩼୯
㪛㫉㫀㪼㪻㩷㫊㫃㫌㪻㪾㪼㩷㫄㫆㫀㫊㫌㫋㫌㫉㪼㩷㪺㫆㫅㫋㪼㫅㫋䋨䋦䋩㪈㪅㪏㪟㪈㪌㪅㪋㪌㪇㩼䌾 㪤㪸㫏㪋㪅㪉㪐㪇㩼㪇㪅㪐 㪤㫀㫅
㪉㪅㪍
㫍㪸㫃㫌㪼
㪦㪺㪺㫌㫇㪸㫋㫀㫆㫅㩷㫍㪸㫃㫌㪼㪦㪺㪺㫌㫇㪸㫋㫀㫆㫅㩷㫍㪸㫃㫌㪼 㫍㪸㫃㫌㪼㪘㫇㫉㩷㩾㪇㪊䌾 㪋㪅㪉㪇㪅㪎 㪉㪅㪍
㪟㪈㪌㪅㪏㪈㪅㪏㪇㪅㪌 㪇㪅㪐䌾 㪈㪅㪌㪘㫌㪾㩷㩾㪇㪊㪇㪅㪎 㪇㪅㪐 㪇㪅㪐㪇㪅㪌 䌾 㪈㪅㪌㪥㫆㫍㩷㩾㪇㪊㪈㪅㪈 㪈㪅㪈 㪈㪅㪋㪇㪅㪏 䌾 㪈㪅㪍㪟㪈㪌㪅㪈㪈㪇㪅㪏 䌾 㪈㪅㪍㪡㪸㫅㩷㩾㪇㪋㪈㪅㪉 㪈㪅㪋 㪈㪅㪌㪇㪅㪋 䌾 㪈㪅㪌㪈㪅㪉㪟㪈㪍㪅㪈㪇㪅㪋 䌾 㪈㪅㪌
㪈㪅㪌

15/22

Fig.4 Accumulation frequency distribution ofDried sludge moisture at the four seasons㩷㪇㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪈㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪉㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪊㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪋㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪌㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪍







ᴤ᷷ੇ῎ᳪᵆ฽᳓₸
sludge Moisuture content㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷 Dried䋨䋦䋩

03䂾䊶䊶䊶Apr -㧠᦬03䂓䊶䊶䊶Aug -㧤᦬- 03
䂹䊶䊶䊶Nov ᦬
04䂥䊶䊶䊶Jan -㧝᦬

4. Performance evaluation research result

4.1 Dry performance(1) Comparison with another biomasses(2) Effect of heatheat-trapping gas reduction

3.3 Possibility of effective use for sewage dried sludge

3.2 Economy
Trial calculation of cost
(1) Construction cost(2) Maintenance management cost(3) Integrated cost

3. Performance evaluation research Content⚥Ⓧ㗫ᐲ
Accum ulation fre q uency- 229 -

Investigation result

0.9㨪4.2
34
䋭

Moisuture content㧔㧑㧕
Cooking oil waste content㧔㧑㧕higher calorific value㧔kJ/kg-DS㧕



10

79㨪82



10

81㨪82

Digested sludge

Nov-03Time
Aug-03



10

81㨪86

Jan-04

120

10

80

Targetvalue

20,00037

0.5㨪1.5䋭36

0.5㨪1.5㪉㪉㪃㪈㪇㪇

34

0.4㨪1.7

㻍3

14/22

㻍20,000

30㨪40¥1,379¥11,173¥4,350¥2,224¥2,107

Subtotal Ԙ
Utility
Labor
Normal shutdown㪈㪊㪊㪅㪉㪌㩷͐㪌㪏㪅㪉㪍㩷͐㪈㪋㪅㪈㪋㩷͐㪈㪋㪅㪐㪊㩷͐㪉㪐㪅㪈㪐㩷͐㪎㪋㪅㪐㪐㩷͐㪐㪅㪉㪍㩷͐

㪌㪏㪅㪌㪍㩷͐㪎㪅㪈㪎㩷͐

€㩷㪆䌴㪄㫎㪼㫋

㶎. Equipment driving time 䋺 䋲䋴䌨䌲䋯Day
㶎䋮The equipment life 䋺 䋱䋰Years¥19,854¥8,681¥8,725

Plant machine
Plant electrical

Subtotal 㽳¥1,069䎂㪆䌴㪄㫎㪼㫋
Civil engineeringand construction

Integrated cost‫ޓ‬Ԙ㧗ԙ

Maintenancemanagement

construction

Cost item

Cost to process
dewatered sludge by 1t-wet

16/22

Tab.3 the trial calculation result of the cost

4. Performance evaluation research result
4.2
4.2 Economy

Quality ofdried
sludge



10

80㨪84

Apr-03

Mixture ratio of heat medium oil
0.64㨪0.75 0.64㨪0.69 0.65㨪0.69 0.64㨪0.69 0.6㨪0.8
㧟㧔㨙 /t-wet㧕Dry time 㧔min㧕

Processing Amount of processing of dewateredsludge㧔t-wet㧛batch㧕
condition

Moisuture content㧔㧑㧕

Sludge of processed object

Investigation item

Tab.2 Dry performance result

4.1 Dry performance

4. Performance evaluation research result

- 230 -㨪

㪊㪃㪉㪊㪇䌾㪊㪃㪏㪉㪇6,211㨪

㪈㪊㪃㪌㪉㪈䌾
㪈㪌㪃㪐㪐㪈

26,000Carbonization
construction waste

Carbonization food waste

Coal (reference value)
9.05

䋭

㧙

䋭

㪊㪐䌾㪈㪐㪇

䋭

20㪊㪏㪅㪈䌾㪋㪈㪅㪏䋭㪈㪊㪃㪇㪇㪇䌾
㪈㪎㪃㪇㪇㪇

㨪 㨪㪇㪅㪊䌾㪊㪅㪌

㪎㪋䌾㪏㪌



%JNQTKPG
EQPVGPV
㫄䌧䋯㫂䌧

17/22

1,300

㪊㪉㪊䌾㪋㪉㪇

㨪


㪉㪃㪎㪇㪊䌾
㪊㪎㪃㪈㪈㪎

㪐㪋䌾㪈㪈㪈

㨪

㫂䌊䋯㫂䌧

*%8㧛#%̪

19/22

䂾 The stable operation of equipment
can have been done䂾 The amount of the heat-trapping
gas exhaust can be reduced

5. Summary of performance
evaluation research䂾 The performance target was able tobe satisfied

㶎. HCV䋯AC 䋺 Higher calorific value䋯Ash content

Wood
waste

㪉㪃㪉㪍㪇䌾㪉㪃㪍㪍㪇㪏㪃㪇㪇㪇䌾㪏㪃㪉㪇㪇 㪈㪃㪐㪈㪈䌾㪈㪃㪐㪌㪐䋭㨪
㨪 㨪䌫㪡䋯㫂䌧㪄㪛㪪

㪐㪃㪋㪍㪇䌾
㪈㪈㪃㪈㪊㪌

Carbonization
sewage sludge

Dried 䌳䌬䌵䌤䌧䌥㶎

MoisutureAshcontent
content䌫㪺㪸㫃䋯㫂䌧㪄㪛㪪䋦䋦㪄㪛㪪

Higher calorific value

Carbonization
woods waste

SewagesludgeBiomass

Analysis result

Tab.4 Comparison with other biomasses

4.3 Possibility of effective use for sewage dried sludge

4. Performance evaluation research result

㪍㪅㪍)TGGPHCTONCPF

㪉㪅㪌

㪍㪅㪍

㪋㪉㪅㪎

㪍㪅㪍

㪊㪍䌴㪄㪚 㪦㪉㫉 㪼㪻㫌㪺㫋 㫀㫆㫅

18/22

Dried sludge
44,000䌴䌯䌮/䌙䌥䌡䌲

reduction Import coal

20/22

3,960,000䌴䌯䌮/䌙䌥䌡䌲Power supply
2,000MWThermal power station
Import coal
4,400,000䌴䌯䌮/䌙䌥䌡䌲

MIKASAGAWA
Treatment Center

110,000ton-CO2/Year
reduction

Possibility of effective use in the future

Fig.5 Effect of heat-trapping gas reduction㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪼㫏㪿㪸㫌㫊㫋㩷㪸㪺㪺㫆㫉㪻㫀㫅㪾㩷㫋㫆㩷㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪻㫉㫀㫍㫀㫅㪾㪃㩷㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪺㫆㫅㫊㫋㫉㫌㪺㫋㫀㫆㫅㪃㩷㪸㫅㪻㩷㪽㪸㪺㫀㫃㫀㫋㫀㪼㫊㩷㪸㪹㪸㫅㪻㫆㫅㫄㪼㫅㫋㽳%GOGPVTCYOCVGTKCNCPFUWRRNGOGPVCT[HWGN

㪋㪌䌴㪄㪚 㪦㪉㫉 㪼㪻㫌㪺㫋 㫀㫆㫅#NVGTPCVKXGHQUUKNHWGN㪌㪈㪅㪍㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪼㫏㪿㪸㫌㫊㫋㩷㫉㪼㪻㫌㪺㫋㫀㫆㫅㩷㪹㫐㩷㪼㪽㪽㪼㪺㫋㫀㫍㪼㩷㫌㫊㪼㩷㽲

㪇㪅㪇

㪈㪇㪅㪇

㪉㪇㪅㪇

㪊㪇㪅㪇

㪋㪇㪅㪇

㪌㪇㪅㪇

㪍㪇㪅㪇

4.3 Possibility of effective use for sewage dried sludge

4. Performance evaluation research result䌴㪄䌃䌏 䋲 䋯㪛㪸䌹- 231 -

㪈㪃㪋㪇㪇

㪈㪐㪐㪇

㪈㪃㪉㪊㪎

㪉㪇㪇㪋

㪈㪃㪊㪌㪌

㪈㪃㪈㪍㪊

㪄㪈㪈㪊㫄㫀㫃㫃㫀㫆㫅㫋㫆㫅㪄㪚㪦㪉

㪉㪇㪈㪇㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㫇㫉㫆㫄㫀㫊㪼㪻㩷㪼㫏㪿㪸㫌㫊㫋㪹㫐㩷㪢㫐㫆㫋㫆㩷㪧㫉㫆㫋㫆㪺㫆㫃

㪄㪍㪅㪇㩼

㪄㪐㪅㪌㩼

21/22

reference

The technology of sewage sludge drying
using an oil bath under diminished pressure

Fig Heat-trapping gas exhaust amountresults value and promised value

㪈㪃㪇㪇㪇

㪈㪃㪈㪇㪇

㪈㪃㪉㪇㪇

㪈㪃㪊㪇㪇

㪘㫄㫆㫌㫅㫋㩷㫆㪽㩷㪿㪼㪸㫋㪄㫋㫉㪸㫇㫇㫀㫅㪾㩷㪾㪸㫊㩷㪼㫏㪿㪸㫌㫊㫋㩿㫄㫀㫃㫃㫀㫆㫅㫋㫆㫅㪄㪚㪦㪉㪆㫐㪼㪸㫉㪀㪜㫃㪼㪺㫋㫉㫀㪺
㫇㫆㫎㪼㫉㪮㪸㫊㫋㪼㫎㪸㫋㪼㫉㪫㫉㪸㫅㫊㫇㫆㫉㫋㪸㫋㫀㫆㫅㪮㪸㫋㪼㫉㩷㫊㫌㫇㫇㫃㫐㪢㪼㫉㫆㫊㪼㫅㪼

㪛㫀㪾㪼㫊㫋㫀㫆㫅㪾㪸㫊㪜㪽㪽㪼㪺㫋㫀㫍㪼㩷㫌㫊㪼㫉㪤㪼㪻㫀㪺㫀㫅㪼

㪦㫀㫃㩷㫎㪸㫊㫋㪼㫊㫌㫇㫇㫃㫐㩷㪺㫆㫄㫇㪸㫅㫐㪩㪼㪺㪼㫀㫍㫀㫅㪾㩷㫎㪸㫋㪼㫉㩷㪹㫆㪻㫐㩿㫋㫉㪼㪸㫋㪼㪻㩷㫎㪸㫊㫋㪼㫎㪸㫋㪼㫉㪀㫋㪿㪼㩷㪸㫄㫆㫌㫅㫋㩷㫆㪽㩷㫋㪿㪼㩷㫉㪼㪻㫌㪺㫋㫀㫆㫅㩷㫆㪽㩷㫋㪿㪼㩷㪿㪼㪸㫋㪄㫋㫉㪸㫇㫇㫀㫅㪾㩷㪾㪸㫊㫋㪿㪸㫋㩷㪺㪸㫅㩷㪹㪼㩷㫉㪼㪻㫌㪺㪼㪻㩷㫎㪿㪼㫅㩷㪼㪽㪽㪼㪺㫋㫀㫍㪼㫃㫐㩷㫌㫊㫀㫅㪾㩷㫀㫋㪅㫋㪿㪼㩷㪸㫄㫆㫌㫅㫋㩷㫆㪽㩷㪾㪼㫅㪼㫉㪸㫋㫀㫆㫅㩷㫆㪽㩷㫋㪿㪼㩷㪿㪼㪸㫋㪄㫋㫉㪸㫇㫇㫀㫅㪾㩷㪾㪸㫊㪾㪼㫅㪼㫉㪸㫋㪼㪻㩷㫎㪿㪼㫅㩷㪻㫉㫀㪼㪻㩷㫊㫃㫌㪻㪾㪼㩷㫀㫊㩷㫇㫉㫆㪻㫌㪺㪼㪻㪅㪫㫉㪸㫅㫊㫇㫆㫉㫋㪸㫋㫀㫆㫅㪫㪿㪼㩷㪻㫉㫐㩷㫇㫉㫆㪺㪼㫊㫊㪫㪿㫀㪺㫂㪼㫅㫀㫅㪾䋯㪛㫀㪾㪼㫊㫋㫀㫆㫅䋯㪛㪼㫎㪸㫋㪼㫉㪮㪸㫊㫋㪼㫎㪸㫋㪼㫉㩷㫋㫉㪼㪸㫋㫄㪼㫅㫋㩷㪽㪸㪺㫀㫃㫀㫋㫐㪫㫉㪼㪸㫋㫄㪼㫅㫋㩷㪺㪼㫅㫋㪼㫉㩷㫀㫅㫊㫀㪻㪼㪦㫌㫋㫊㫀㪻㪼

Range of trial calculation ofamount of heat-trapping gas exhaust

22/22

The technology of sewage sludge drying
using an oil bath under diminished pressureThank you for listening䋣- 232 -Normal shutdown

Labor

Electric power ¥8.2/kWh Kerosene ¥33.6/L Digestion gas Free
Water supply ¥565/m3 Oil waste ¥26/kg Clean can medicine ¥1,229/kg
Boiler water processing medicine ¥1,428/kg㽲㪪㫃㫌㪻㪾㪼㩷㫄㫀㫏㫀㫅㪾㫋㪸㫅㫂㽷㪛㫉㫀㪼㪻㩷㫊㫃㫌㪻㪾㪼㪿㫆㫇㫇㪼㫉

㽸

Utility㪣㪼㪾㪸㫃㩷㪺㪿㪼㪺㫂㩷㫆㪽㩷㪹㫆㫀㫃㪼㫉㩷㪆㪧㪼㫉㫀㫆㪻㫀㪺㪸㫃㩷㫉㪼㫇㪸㫀㫉㩷㫆㪽㩷㪻㫉㫐㪼㫉㩷㪆㪘㫅㪸㫃㫐㫊㫀㫊㩷㪼㫏㫇㪼㫅㫊㪼㩿㫎㪸㫋㪼㫉㩷㫈㫌㪸㫃㫀㫋㫐㩷㪸㫅㪻㩷㫊㫋㫀㫅㫂㪀㩷㪆㪚㫆㫅㫊㫌㫄㫇㫋㫀㫆㫅㩷㫄㪸㫋㪼㫉㫀㪸㫃㩷㫇㫌㫉㪺㪿㪸㫊㪼㩷㪼㫏㫇㪼㫅㫊㪼㽲㪍㩷㪽㫌㫃㫃㪄㫋㫀㫄㪼㩷㫇㪼㫆㫇㫃㪼㩷㪸㫅㪻㩷㪉㩷㫅㫀㪾㪿㫋㩷㫊㪿㫀㪽㫋㩷㫇㪼㫆㫇㫃㪼㪜㫃㪼㪺㫋㫉㫀㪺㩷㫇㫆㫎㪼㫉㩷㪆㩷㪢㪼㫉㫆㫊㪼㫅㪼㩷㪆㩷㪛㫀㪾㪼㫊㫋㫀㫆㫅㩷㪾㪸㫊㩷㪆㩷㪮㪸㫋㪼㫉㩷㫊㫌㫇㫇㫃㫐㩷㪆㩷㪦㫀㫃㩷㫎㪸㫊㫋㪼㩷㪆㩷㪤㪼㪻㫀㪺㫀㫅㪼

Plant electrical

Plant machine

Civil engineeringand construction

Trial calculation unit price

Maintenancemanagement

construction

Cost item

Range of trial calculation of cost

㽵

㽶

㽻

䃂

㽷

㽺
㪚㫆㫅㪻㪼㫅㫊㪼㫉㽹㪤㪸㫀㫅㩷㪹㫆㫀㫃㪼㫉㪪㫃㫌㪻㪾㪼㩷㪻㫉㫐㪼㫉㽴㪭㪸㪺㫌㫌㫄㩷㫇㫌㫄㫇㽵㪦㫀㫃㩷㫊㪼㫇㪸㫉㪸㫋㫆㫉㩿㫋㪿㪼㩷㪈㫊㫋㩷㫊㫋㪸㪾㪼㪀㽻䃂㽶㪦㫀㫃㩷㫊㪼㫇㪸㫉㪸㫋㫆㫉㩿㫋㪿㪼㩷㪉㫅㪻㩷㫊㫋㪸㪾㪼㪀㽼㪺㫆㫄㪹㫌㫊㫋㫀㫆㫅㪽㫌㫉㫅㪸㪺㪼

㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪺㫆㫆㫂㫀㫅㪾㩷㫆㫀㫃㩷㫎㪸㫊㫋㪼㫊䇭㫃㫀㫅㪼㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㫊㫋㪼㪸㫄䇭㫃㫀㫅㪼㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㪼㫍㪸㫇㫆㫉㪸㫋㫀㫆㫅㩷㫄㫆㫀㫊㫋㫌㫉㪼㩷㪸㫅㪻㩷㪻㫉㫐㩷㪼㫏㪿㪸㫌㫊㫋㩷㫃㫀㫅㪼㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㩷㫊㫃㫌㪻㪾㪼䇭㫃㫀㫅㪼

㽴

㽺

㽼

Fig.3 Plant equipment flow㽳㪧㫉㪼㪄㪿㪼㪸㫋㫀㫅㪾㫋㪸㫅㫂㽸㪦㫀㫃㩷㫊㫋㫆㫉㪸㪾㪼
㫋㪸㫅㫂

㽳

㽹

Basic flow of this equipment

Utilization of Regional Biomass Centered on Wastewater Treatment Plants
Masaaki Ozaki, Shuichi Ochi
Material and Geotechnical Engineering Research Group, Public Works Research InstituteMinamihara 1-6, Tsukuba city, Japan, 305-8516, ozaki@pwri.go.jp
Abstract: The purpose of this research is to utilize regional biomass at wastewater treatment plants.
Organic waste produced by the operation of infrastructure was considered to have big potential asregional biomass, so its the mass production was investigated. To permit the utilization of organic
materials such as trees and grass, the anaerobic co-digestion with bio-solid method and theslurry-compost of digestion sludge method were investigated. And finally, the maximum supply of
biogas was estimated and technology needed to use it as fuel of natural gas vehicles was discussed.
Keywords: steam-exploded wood, anaerobic co-digestion, slurry-compost, natural gas vehicle

Generated Sludge (1,000DSt)

1. Introduction
In Japan in FY 2003, approximately 36% of bio-solid was disposed of as landfill andapproximately 64% was used beneficially. In recent years, the rate of landfill has decreased andthat of beneficial use has steadily increased as indicated in Figure 1. Bio-solid was utilized mainly
on agriculture land. Recently incinerated ash and molten slag have been used as construction
materials: for cement production and as aggregate.
Energy utilization of bio-solid is classified mainly as two methods. One is biogas, whichis generated from anaerobic digestion and includes methane gas as its main constituent. The otheris solid fuel, which is made of bio-solid. Biogas is usually consumed in wastewater treatment
plant (WWTP), at digestion facilities, and in incinerators, but approximately 30% of that is left overand burned off.

2,500
Others
2,000

Fuel material
Agriculture land

1,500

Cement ingredient
1,000

Building material

500

Ocean dunping
Land reclamation

0
89 90 91 92 93 94 95 96 97 98 99 00 01 02 03
FY

Figure-1 Transition of generated bio-solid- 233 -

After the Kyoto Protocol came into effect in February 2005, the value of biogas has beentransformed from in-house consumption to positive utilization. Biogas is expected to be an energy
source that is characterized by carbon neutrality. And in this research, biogas is discussed mainly
from the viewpoint of regional biomass utilization.
2. Estimation of regional biomass production
Various initiatives have been taken in the field of biomass utilization, contributing to
reduced CO2 emission and becoming very important elements in measures to fight global warming.
Several problems face biomass utilization. Its collection and transportation is very costly,
because biomass is widely scattered in each region. And the facilities are small scale so they lackscale merit. Biomass is classified into waste biomass, unutilized biomass and resource vegetation.
It is assumed that waste biomass such as food waste and wood generated by construction will beutilized quickly, because this waste biomass has been collected at specific places.
A large amount of vegetation waste is generated by river dike maintenance and trimming
street-side trees. But it is difficult to say that vegetation waste is well utilized. For example,
vegetation waste generated in suburban areas is incinerated with municipal solid waste. And its
beneficial use for agriculture is restricted
Because the amount of vegetation waste from infrastructure operation is not included inorganic resources, it is not expected that the use of vegetation waste will increase in the near future.
If the amount of vegetation waste was precisely measured, utilization plans and methods would be
investigated by an assessment based on a feasibility study. And if the resource information wereopen to the public, private companies would have opportunities to conduct case studies.
The amounts of driftwood at approximately 200 dams in Japan were investigated during
2003 and 20051). As a result, the total volume of driftwood around dam reservoirs was estimated,
obtaining a rough value. This shows that to promote the utilization of driftwood as biomass
resources in the future, it will be necessary to continue the collection of these basic data, and to alsoestablish a driftwood utilization system by referring to advanced initiatives.
Table 1 indicates the types of public works that produce biomass. To study biomass
utilization, first, the amount and kinds of generated biomass will be precisely investigated. Next,
the total volume produced in Japan will be estimated. Lastly, information management systems
will be investigated.
Table-1 Kinds of biomass generated from national land manegementadministrative
infrastructure, land and transport
sectionroad
freeway, national highway, local highway
river
river, dam, erosion control, seashorecity
street, park, sewarage
airportrunwayharborwaterfront
railwayrailroad* biomass: grass, branches and leaves, drifwood, bio-solid- 234 -

3. Recycling technology for organic waste
To promote the utilization of organic waste such as trees, and grass and bio-solid, recycling
technology was developed considering the characteristics of both materials. From the results, it
was concluded that anaerobic co-digestion of steam-exploded wood and bio-solid is feasible andcan make a big contribution to biogas production. And the slurry-compost, method which
contributes to agriculture use of bio-solid, was developed to treat fermentation residue.
It was observed that crushed wood is useful as bio-solid dewatering agent. And it wasalso observed that steam exploded wood with a small amount of bio-solid is an adequate compostthat is usable as an, gardening material that can replace peat moss.
slurry-compost were considered by this research.

Anaerobic co-digestion and⹜ᢱᛩ౉Sampleinvestment

3.1 Anaerobic co-digestion
Wood material and dried grassalone are difficult to ferment and theyneed to be changed to a quality easily usedbymicroorganisms.
Thesteam-explosion method was investigated,
as indicated in Figure 2. This method
keeps samples at a high temperature andunder high steam pressure for a certain
time period then suddenly reduces thepressure. After that, the plant materials
are shattered and softened.
Methane fermentationwas

Steam drain
→㩷ឃ⫳᳇

Steam
⫳᳇ 䇭→

Pressure vessel
ട࿶ኈེ
䋳䋰㩷㪣

Silencer䉰䉟䊧䊮䉰䊷Steam-exploded
material῜⎈‛

Figure㧙2 Steam-explosion Device

done

using

steam-exploded

wood

and

bio-solid.

Steam-exploded broadleaf tree chips prepared under pressure of 2MPa for 15minutes, that wereconfirmed to be easy degradable by a preliminary examination, were used for the experiment. The
sequential experiment was done by inserting and removing samples once per day at 35 degrees for
50 days, while varying the ratio of the added plant waste to the bio-solid.
The methane gas productivity is important when the anaerobic co-digestion process isintroduced at an actual facility. But it is feared that the whole process might change into acidfermentation, because of overloading of the function of the existing digestion tank. In a laboratory,
the system does not change into acid fermentation but works well. Figure 3 shows the averagemethane gas recovered from steam-exploded wood and bio-solid under each condition after theexperiment process has stabilized. And Figure 4 shows the dissolution characteristic of TOC,
NH4-N and PO4-P in digestion sludge.

- 235 -

㪉㪇

㪈㪇

㪇
㪇 㪅㪉㪌

㪇㪅㪌

㪇㪅㪎㪌

㪈

㪈㪅 㪉㪌

ᷙวᲧ䇭䋨ᧁ⾰῜⎈‛㩷㪛㪪㩷䋯㩷ਅ᳓ᳪᵆ㩷㪫㪪䋩
Ratio
of organic waste addition to bio-solid(steam-exploded wood / bio-solid )㪈㪉 㪌㪇䋨㫄㪾䋯 㪣䋩

Dissolutionṁ⸃ᕈ㩷 㪫㪦 㪚 䋬㪥 㪟 㪋㪄㪥

Ratio䉧䉴
of digestion⊒↢୚₸gas㪊㪊(gas /䋨㫄
investment
material)䋯ᛩ౉㊂㩷㫄
䋩

㪊㪇

㪇

㪫㪦㪚
㪥㪟㪋㪄㪥
㪧㪦㪋㪄㪧

㪈㪌 㪇㪇

㪍㪇
㪌㪇

㪈㪇 㪇㪇

㪋㪇

㪎 㪌㪇

㪊㪇

㪌 㪇㪇

㪉㪇

㪉 㪌㪇

㪈㪇

㪧㪦 㪋㪄㪧䇭䋨㫄㪾 䋯 㪣䋩ో䇭䉧䇭䉴 gas䂔 Generated䊜䉺䊮䉧䉴䂓 Methane
gas

㪋㪇

㪇

㪇

㪇

㪇㪅㪌

㪈

㪈㪅㪌

Ratio of organic waste addition
to bio-solidᷙวᲧ䇭䋨ᧁ⾰῜⎈‛㩷㪛㪪㩷䋯㩷 ਅ᳓ᳪᵆ㩷㪫㪪䋩(steam-exploded wood / bio-solid )Figure㧙3 Recovery of methane gas        Figure㧙4 Dissolution characteristic of  from steam-exploded wood             TOC, NH4-N, PO4-P

The methane gas production increased in proportion to the ratio of added steam-exploded
wood to the bio-solid. On the other hand, a large quantity of soluble TOC and PO4-P tend toremain in digestion sludge, but soluble NH4-N decreased considerably when the steam-exploded
material increased. It is observed that the system has high potential for practical use, if soluble
TOC and PO4-P in digestion sludge can be decreased effectively.
3.2 Slurry-compost2)
When slurry organic material such as bio-solid is utilized on agricultural land, the watercontent of the material is usually decreased by de-watering and compost is made from de-wateredsludge. Slurry-compost is a technology developed to be applied to all kinds of slurry organic
material. Excess sludge and digestion sludge are utilized in this research on the beneficial use offermentation residue.
Slurry-sludge could be stabilized without de-watering if a large quantity of dissolved
oxygen was provided. The purpose of aerobic digestion is not only the reduction of sludge but
also its stabilization. ³Slurry-compost´ would be considered to be an improved aerobic digestion
technology, if oxygen could be provided from a liquid surface by giving it high oxygen content.
The sludge stabilization process can be assessed based on its CO2 production
accompanying the decomposition of its organic material. The transition of generated CO2 isindicated in Figure 5 and Figure 6, where excess sludge (thickened sludge: MLVSS = 26 g/L) anddigestion sludge respectively (MLVSS = 6.8 g/L) were raw materials. The liquid phase(slurry-sludge) was 0.8 L and the gaseous phase (oxygen) was 2.1 L in this experiment. And theoxygen was filled up at pressure of 2 atmospheres and maintained over 30% by filling up again.

- 236 -

㪊㪌㷄

㪌㪇㷄

㪍㪇㷄

㪎㪇㷄

㪏㪇
㪍㪇
㪋㪇
㪉㪇
㪇
㪇

㪌

㪈㪇

㪈㪌

㪉㪇 ᣣ
(days)

㪉㪇㷄㪈㪇㪇㫄㪾㪚㪆㪾㪤㪣㪭㪪㪪㪄ᶖൻᳪᵆ
mgC/gMLVSS- Digestion sludge㫄㪾㪚㪆㪾㪤㪣㪭㪪㪪㪄૛೾ᳪᵆ
mgC/gMLVSS- Excess sludge

㪉㪇㷄
㪈㪇㪇

㪊㪌㷄

㪌㪇㷄

㪍㪇㷄

㪌

㪈㪇

㪈㪌

㪎㪇㷄

㪏㪇
㪍㪇
㪋㪇
㪉㪇
㪇
㪇

(days)㪉㪇 ᣣ

Figure㧙5 Transition of generated CO2    Figure㧙6 Transition of generated CO2
in excess sludge               in digestion sludge

The amount of generated CO2 differed according to temperature conditions or the kinds ofsludge used as raw material, but it was restrained after two weeks in each case. In particular, it
was observed that the digestion sludge was decomposed quickly under the normal temperature.
Because the digestion sludge was decomposed biologically under an anaerobic atmosphere, it was
assumed that another microorganism population (aerobic microorganism) treated the sludge
biologically under an aerobic atmosphere.
A small-scale facility could be constructed for the slurry-compost method, and it would beeasy to operate. So it is assumed that it would be beneficial in coping with small-scale demandand seasonal fluctuation of production.
4. Maximum supply of biogas3)
The sludge digestion process has been introduced at approximately 350 WWTPs in Japan,
and about 280 million m3 biogas has been generated per year. Power facilities, such as gas engines
or fuel cells, have been installed at some WWTPs. Recently the number has been increased but it
is still limited. About 180 million m3 biogas has been utilized as fuel, including digestion tankheating and as additional fuel for incinerators. But the remaining biogas (about 100 million m3)
has been burned off as excess biogas.
Table 2 indicates the quantity of biogas usable as fuel that is supplied to all WWTPs in
Japan, including cases where hypothetical conditions are set. The hypothetical conditions were
calculated for a case where the quantity of solid material input was over 3.0%, the ratio of digestion
tank utilization was 85% and the digestion period was 20 days, and the digestion tank was heated at
35 degrees by biogas, because there are many WWTPs with surplus capacity to satisfy these factors.
In addition, the biogas of all bio-solid was also calculated.
The remaining biogas will be about 250 million m3 at efficient treatment and about 300
million m3 for digestion of all bio-solid respectively. The reduction of CO2 will approach 200
thousands tons if the existent remaining biogas is totally utilized. This quantity is equivalent tothat adsorbed by about 60 thousands hectare of natural forest.

- 237 -

Table-2 Quantity of biogas supply at total WWTPs
condition of bio-solid
qauntity of remaining quantity of refined
reduction of CO2
treatment at WWTP
biogas (1,000m3)
biogas (1,000m3)(t)present remaining biogas
107,200
53,600199,400
125,600
467,500
efficient treatment
251,300
155,400
578,200
digestion of all bio-solid
310,800* using the data in FY2002 for condition of biogas production

5. Biogas vehicles3)
New beneficial uses of biogas have been introduced and biogas is utilized outside WWTP
after considerable refining. Refined biogas is provided to a plant manufacturing City Gas in
Kanazawa city4). And in Kobe City, a plant has been equipped to supply refined biogas to natural
gas vehicles (city busses, trucks, etc,) .
Biogas has usually been utilized at large-scale WWTPs, but it tends to be burned off at
small-scale WWTPs because of limited users and utilization methods. Biogas is considered to be aresource equal to natural gas when it is refined. It would be possible to drive natural gas vehicles
by fuelling them with refined biogas, so we call such a vehicle a ³biogas vehicle´.
Attempts to power cars by biogas are not a new idea. The ³pressurized gas supply
project´ was carried out in 1942 in Kyoto City during the Second World War. More than 100
Biogas vehicles were driven at the same time, but the project was given up at 1950 because thequantity of biogas available fell as its content in sewerage declined.
Table 3 indicates the quantity of biogas supplied at each WWTP under the same assumed
conditions as in Table 2. About 10 standard cars can be operated as biogas vehicles at WWTP thatretain about 100 thousands m3 of biogas per year. And it is estimated that 60 and 310 normal cars
could be operated at WWTP that retain biogas at rates of about 500 and 2,500 thousands m3 peryear respectively. At large-scale WWTP, more than 4,500 tons of CO2 emissions could be
reduced.
There are several technologies, such as the membrane system, that refine biogas, reducing
CO2 after sulfide separation. It was assumed that adsorption reduction, which uses treatedwastewater at WWTP, would be a useful method. Biogas includes a very small quantity of silicatecompound that originates from shampoo, and this material must be reduced.
On the other hand, the law requires that natural gas vehicle fuel must have an odor. A
fixed quantity of propane gas will be added to fuel for Biogas vehicles to add an odor and perform
calorie coordination. And Biogas vehicle fuel must also be compressed to 20MPa for house use
and small-scale filling up facilities, and to 25MPa for business use. Business use pressure permits
high speed filling and could be applied at gas stations, but an employee responsible for its use must
always be on duty at such facilities.

- 238 -

Table-3 Quantity of biogas supply at each WWTP
WWTP

qauntity of remaining quantity of refined
number of driving biogas vehicles
biogas (1,000m3)
biogas (1,000m3)
normal car 2t packer large bus
large-scale
2,500
1,250
310
250
50
middle-scale
500
250
60
50
10
small-scale
100
50
10
10
2
* driving length per year and per fuel unit, normal car: 60,000km/year and 15km/m3
2t packer: 20,000km/year and 4km/m3, large bus: 50,000km/year and 2km/m3³Natural gas´ supplied by gas companies have been designed as standard fuel for natural
gas vehicles. Each refined biogas must be inspected to confirm that it has the same quality as³natural gas´. If biogas refining systems are standardized, Biogas vehicles will be introduced
easily.
6. Conclusion
Measures to increase biogas production were investigated by this research. These werethe utilization of steam-exploded wood with bio-solid, efficiently using digestion tanks, and bydigesting all bio-solid. For example, a high temperature - high concentration digestion system
works satisfactory in Osaka city6). In the future, Economical anaerobic digestion systems thatprovide a steady high sludge decomposition rate must be done.
It will become increasingly important to develop technologies for utilizing biogas: biogas
vehicle systems for example. In order to utilize regional biomass centered on WWTP, thefollowing issues must be tackled. Utilizing biomass must not only benefit WWTP, but also
regional areas. And it must also be possible to use the fermentation residue.
Reference:
1) Masato TAKAHASHI, Katsuhito MIYAKE, Takanori MAKI, Shuichi OCHI, Masaaki OZAKI, The Amountof Driftwood Flowing into Dam Reservoirs and Examples of its use as Woody Biomass, Civil Engineering
Journal, 48-7, 48-53, 2006 (in Japanese)
2) Tadashi SHOJI, Shuichi OCHI, Masaaki OZAKI, Production and Use of Slurry-compost of Sewage
Sludge, Civil Engineering Journal, 48-6, 40-45, 2006 (in Japanese)3) Takanori MAKI, Masaaki OZAKI, Vehicles Using Digestion Gas as Fuel, Civil Engineering Journal,
47-2, 34-39, 2005 (in Japanese)
4) Sakae HIDUKI, City gas supply using a sewerage system, Reclamation and Utilization, vol.28, no.110,
17-20, 2005 (in Japanese)5) Yoshinori KAWATA, Tsuyoshi TAKIMURA, Hideaki ONISHI, ³Bio-natural gas´ made of digestion gas
and its utilization as fuel for natural gas vehicles, Proceedings of 42nd conference for sewerage research‫ޔ‬
55-57‫ޔ‬2005 (in Japanese)
6) Kiyonori TAIMATSU, Improvement of anaerobic digestion and digestion gas utilization, Reclamationand Utilization, vol.28, no.110, 44-50, 2005 (in Japanese)- 239 -









Biogas Solid fuel

Energy utilization

Incinerated ash
 Molten slag

Agriculture land
 Construction material

Beneficial use of bio-solids

Introduction

Masaaki Ozaki
Public Works Research InstituteUtilization of Regional BiomassCentered on Wastewater
Treatment Plants

89

90 91

92

93

94 95

96
FY

97 98

99

00

Approximately 64% of bio-solids was used beneficially.

0

500

1,000

1,500

2,000

2,500

01 02

03

Land reclamation

Ocean dunping

Building material

Cement ingredient

Agriculture land

Fuel material

OthersTransition of generated bio-solid

Maximum supply of biogas
 Biogas vehiclesAnaerobic co-digestion
 Slurry-compost

Introduction
 Estimation of regional biomass production
 Recycling technologies for organic wasteContents

Generated Sludge (1,000DSt)- 240 -

- 241 -Compost, construction material
 Biogas, solid fuel



Waste
biomass

Green biomass

Regional biomass

Unutilizedbiomass

Resource
vegetation

In-house consumption
 Positive utilization

Utilize the products efficiently

Regional biomass

Vegetation
waste

Gather regional biomass at WWTP
 Step up the production of recycle

Utilization of regional biomass
centered on WWTP

Food waste
Wood generated by construction

Waste biomassInventory system of green biomass

The amount and kinds of generated
biomass will be precisely investigated.
 Total volume produced in Japan will be
estimated.
 Information management systems will
be investigated.

Green biomass utilization

River dike maintenance Trimming street-side trees

Unutilized biomass
 Resource vegetation
 Vegetation waste

Estimation of regional biomass
production

- 242 Technologies for recycling

Alternative material of peat moss
(Thick layer basic materials spaying)
Pilot works for practical use about
the developing and existing usefultechnologies

Data base for biomass

Driftwood into dam reservoirs

Develop the system which provides
and manages the data base of
biomass from each public work.

Recycling and utilizing biomass frompublic works

administrative
infrastructure, land and transport
sectionroad
freeway, national highway, local highway
river
river, dam, erosion control, seashorecity
street, park, sewarage
airportrunwayharborwaterfront
railwayrailroad* biomass: grass, branches and leaves, drifwood, bio-solid

Kinds of biomass generated fromnational land management

Burning up at the field

Spreading over the grass

Bio-solids
SludgeGreenbiomass
Plant
waste

(Slurry（Compost
compost)）Fermentation
Fermentation

Co-digestion
Fermentation

Fertilizer

Alcohol
Organic acid

Methane gas

Recycling technology for organic
waste

Chipping branches

Trimming street-trees (e.g. Tottori river and road office)

MowingRiver dike maintenance (e.g. Edogawa river office)Infrastructure operation at river androad offices

- 243 -Green biomass is shattered and softenedKeep at a high temperature and under highsteam pressure for a certain period Then suddenly reduces the pressure

Steam explosion methodGreen biomass (Wood, dries grass) Bio-solid

Material

Steam-exploded broadleaf tree chips prepared underpressure of 2MPa for 15 minuets.

Wood chips before and after thesteam explosion treatment

(1) Anaerobic co-digestion

Recycling technology for organic waste

Steam
蒸気 →

Steam-exploded
material
爆砕物

Silencer
サイレンサー

Steam drain→ 排蒸気

Inserting and removing samples once per day at 35
degrees for 50 days, while varying the ratio of theadded plant waste to the bio-solid.

Sequential methane fermentation
experimentPressure vessel
加圧容器
３０ L

試料投入
Sampleinvestment

Steam-explosion device

Ratioガス
of digestiongas
発生倍率(gas / investment
material)
3
3

0

10

20

30

0.25

0.5

0.75

1

1.25

(steam-exploded wood / bio-solid )organic
to 水
bio-solid
混Ratio
合 比 of（木質 爆waste
砕 物 addition
DS ／ 下汚 泥 TS）

0

全 ガ ス□ Generated
gas
メタンガス
■ Methane
gas





All kinds of slurry organic material“an improved aerobic digestion”

Considered to beThe reduction of sludge and its stabilization
 Oxygen could be provided from a liquidsurface by giving it high oxygen content“Slurry-compost”

Material(2) Slurry-compost

Recycling technology for organic waste

Methane gas production increased in proportion to
the ratio of added steam-exploded wood to the biosolid.

（m ／投入量 m ）

40

0

20

40

60

80

0

20℃
100

（mg／ L）
0

0

10

20

500
250

30

750

50

60

40

0.5
1
1.5
混 合Ratio
比 （of木organic
質 爆 砕waste
物 Daddition
S ／ 下to水bio-solid
汚 泥 TS）(steam-exploded wood / bio-solid )

0

TOC
NH4-N
PO4-P

1000

1250

1500

10

50℃

15

60℃

日
20 (days)

70℃

0

20

40

60

80

0

20℃
100

5

35℃

10

50℃

Digestion Sludge

15

60℃

Because the digestion sludge was decomposed biologically under an anaerobic
atmosphere, it was assumed that aerobic microorganism treated the sludge.

Digestion sludge was decomposed quickly under the normal temperature.

5

35℃

Excess Sludge

Transition of generated CO2

A large quantity of soluble TOC and PO4-P tend to remain indigestion sludge, but soluble NH4-N decreased considerably
when the steam-exploded material increased.

Dissolution
溶 解 性 T O C ， N H 4- N

Dissolution characteristics of TOC,
NH4-N, PO4-P
PO 4- P （ m g／ L）

Recovery of methane gas fromsteam-exploded wood

mgC/gMLVSS-消化汚泥
mgC/gMLVSS- Digestion sludge- 244 mgC/gMLVSS-余剰汚泥
mgC/gMLVSS- Excess sludge

(day
20 日

70℃

- 245 -

焼却炉補助燃料
Incinerator
44%
fuel 44%

Beneficial
Use 37%

有効利用量
37%

Bio-gas was generated 280 million m3 per year in Japan.
And approximately 30% is left over and burned off

Tank heating34%

嫌気性消化への熱供給利用量
34%

Left over
未利用量
29%29%

Airその他
Others 6%
con6%
Dry
場内冷暖房
fuel3% 3%
汚泥乾燥
6%
6%
Power
generation
41%

ガス発電
41%

Recently the number has been increased
but it is still limited.

Utilization of biogas

Digestion process has been introduced
at approximately 350 WWTP.
 Power facilities, such as gas engines or
fuel cells, have been installed at some
WWTP.

Maximum supply of biogas

0 km

150

3. In addition, the biogas of all bio-solid was calculated.

Hypothetical conditions:
1. The quantity of solid material input was over 3.0%.
2. The ratio of digestion tank was 85% and the digestion period was 20 days,
and the digestion tank was heated at 35 degrees by biogas.

condition of bio-solid
qauntity of remaining quantity of refined
reduction of CO2
treatment at WWTP
biogas (1,000m3)
biogas (1,000m3)(t)present remaining biogas
107,200
53,600199,400
efficient treatment
251,300
125,600
467,500
digestion of all bio-solid
310,800
155,400
578,200* using the data in FY2002 for condition of biogas production

Quantity of biogas supply
at total WWTP

1,000,000～

Generated bio-gas(m3/year)

Distribution of digestion facilities

- 246 -Biogas is utilized outside, such as City gas,
WWTP after considerable refining.

“Biogas vehicles”

Refined biogas = natural gas

Natural gas vehicles

New beneficial use of biogas

Spring 2008 open3
 2,000m /day
 40 buses (50km/day)

Full-scale plant(PWRI, Kobe City, KOBELCO ECO-SOLUTIONS CO.)Refined biogas = 98% methane gas Kobe city bus opened the business from2nd October, 2006

Kobe biogas

Kobe biogas

Biogas vehicles

City gas has been designed as standard
fuel for natural gas vehicles.
 Each refined biogas must be inspected toconform that it has the same quality as“natural gas”.
 If biogas refining systems are standardized,
biogas vehicles will be introduced easily.
Standardization of biogas

Small-scale:
About 10 standard cars could be operated as “Biogas vehicles” at WWTP thatretain about 100 thousands m3 of biogas per year.

Large-scale:
The “pressurized gas supply project” was carried out during 1942-1950.
More than 100 biogas vehicles were driven at the same time.

qauntity of remaining quantity of refined
number of driving biogas vehicles
biogas (1,000m3)
biogas (1,000m3)
normal car 2t packer large bus
large-scale
2,500
1,250
310
250
50
middle-scale
500
250
60
50
10
small-scale
100
50
10
10
2
* driving length per year and per fuel unit, normal car: 60,000km/year and 15km/m3
2t packer: 20,000km/year and 4km/m3, large bus: 50,000km/year and 2km/m3

WWTP

Number of driving biogas vehicles
at each WWTP







Left small tank: adsorption type
Right big tank: usual typeGas storage tank by adsorption(e.g. Tsuruoka city)

Change vegetation waste into green biomass



Biogas vehicles system

Technologies for utilizing biogas

Economical co-digestion system Utilization of fermentation residue

Recycling technology for green biomass

Data base of regional biomassGasmolecule

Compression zone

Summary

Adsorption media

Adsorption zone

Biogas adsorption system

発電

水素化

Generation
発電

Regional utilization

Household

家庭・地域へ遠隔輸送利用Transportation

Vehicles
自動車

横置き（大型）
Adsorption
tank (large-scale)

吸着貯蔵

縦置き（コンパクト型）
Adsorption
tank (smallscale)

吸着貯蔵

ガススティションGas
station

City都市ガス
gas

Naturalgas vehicles
天然ガス自動車

0

500

1,000

1,500

2,000

2,500

89

90

91

92

93

94

95

FY

96

97

98

99

00

01

02

03

Slag
Ash
CarbonDried
CompostDewatered
SlurryTransition of generated bio-solid

廃熱は、メタン発酵槽の加Fermentation
tank heating
温に用いるガス精製機器棟
Biogasrefining plant

Methane
メタン発酵槽
fermentation
tank

各種のバイオマス
Regional
biomass

Biogas utilization project

Generated Sludge(1,000DSt)- 247 -

1

Reuse of Treated Wastewater
Stefania Paris1, Franz Bischof 2, Hans G. Huber1
1

Hans Huber AG, Maschinen- und Anlagenbau, Industriepark Erasbach A1, D-92334 Berching (Email: info@huber.de)2

University of Applied Sciences, Department of Environmental Engineering, Kaiser-Wilhelm-Ring 23,
D-92224 Amberg, Germany (E-mail: f.bischof@h-amberg-weiden.de)1

Introduction

Even in the 21st century approximately 1.1 billion people on our planet still have no access to clean
drinking water and more than 2.6 billion people have to live without sanitary facilities (WHO/UNICEF,
2005). Estimations indicate that less than 10 % of the wastewater being produced on earth has beentreated prior to being discharged. Approximately 12,000 km³ wastewater are distributed in ourenvironment, which is comparably more than half the volume of the Baltic Sea (approx. 22,000 km³,
BMU).
Polluted drinking water and insufficient wastewater disposal are the causes for the majority of all
diseases occurring in emerging and developing countries. Up to 50 % of the worldwide stationary
treated diseases are gastro-intestinal infections, such as cholera, dysentery and typhus. According to
WHO and UNICEF (2005) up to 4,500 children per day die from diseases that are passed on throughpolluted water.
The inextricable link and mutual dependences between economic growth and prosperity, water supply
and wastewater disposal, poverty, epidemics and criminality induced the United Nations in theirplenary meeting in 2000 to define and resolve their Millennium Development Goals (MDGs), thederived aim of which is among others, by 2015, to halve the number of human beings without accessto clean drinking water and those without access to sanitary facilities. How ambitious this plan isshows a calculation according to which wastewater treatment plants for 900,000 people would have to
be built every working day (Cornel, 2004).
But the conventional sanitary concept and technologies developed and optimised in the richindustrialised countries in the course of decades are no sustainable solution to the problems in areas
with water shortage. The main reasons against the extensive application of conventional wastewater
treatment systems are their significant investment and operating costs, the high water consumption
for transport of faeces, urine and other wastes, and the elimination of valuable nutrients. Furthermore,
effluents from conventional wastewater treatment plants are discharged into water courses andtherefore not available for reuse.
The unstoppable population growth in many parts of the world, the necessity to use nutrients for
agricultural production of food and the intention to at least approximately achieve the MDGs make itimperative to pursue different and partly completely new strategies of wastewater disposal. According
to WHO (2006) ”the use of wastewater in agriculture can help communities to grow more food andmake use of precious water and nutrient resources. However it should be done safely to maximize
public health gains and environmental benefits”. In this connection, wastewater is recognised as“value water”. The epoch of mere wastewater disposal is drawing to its end and will be superseded by
the era of wastewater recycling with creation of value.
Also HUBER operates with this in mind and develops partly completely new approaches, which aretested with the respective countries and adapted to their specific local conditions. By using alternative
sanitary concepts and practising the reuse of water and valuable material contained within
wastewater also in their own office building HUBER is contributing to a substantial paradigm shift in
wastewater treatment.

- 249 -

2
2

New approaches

Approaches to alternative solutions reach from reuse of rainwater, irrigation with treated wastewater
up to the recovery of nutrients and their reuse for agricultural purposes. Especially the separate
treatment of the individual flows of domestic wastewater proves to be reasonable. Like it is common
practice in industries already, the critical wastewater flows are collected separately directly at source
and treated on site to provide for their reuse.
For example, the retention of urine from the main wastewater flow and its treatment (recovery of highconcentration nutrients and/or destruction of problematic substances) allow the design of small andeasy to operate treatment plants without the necessity for cost and energy intensive nitrification anddenitrification. In addition, the separate collection of urine reduces the micro pollution load on theaquatic environment.
The separation of the quantitatively biggest part of the wastewater, the greywater (effluent from hand
washbasins, dishwashers, washing machines, showers, bathtubs), and its treatment directly at sourceor close at source in semi-centralised units, which produces high quality service water, provides for a
multitude of water reuse options. The consideration and technical possibilities of decentralised energy
recovery from relatively warm shower and bathtub water are still in the initial stage. The advantage isthat the availability of the regenerative energy source is independent of the time of day, season or
region.
Even treatment of brown water alone (faeces and flush water) or faeces combined with bio-waste inhigh-performance anaerobic reactors seems to be reasonable in many countries since biogas is
produced in the treatment process. If the fermentation process takes place under thermophilic
conditions, this reduces the number of pathogenic germs and provides thus for direct reuse of thesource materials for agricultural applications.

3

Research in HUBER

The concepts and approaches described under chapter 2 are the focus of several research projects,
which the company is running at home and abroad in close cooperation with universities or on its
own. Special priority is given to the country-specific ecological and socio-economic requirements of
the local population when adapting the design of new developments and then realising them in theform of demonstration or pilot units. The goal is to increase the acceptance of new system solutions,and thus ultimately the export chances for the company's technologies, by means of knowhow
transfer and participatory processes in which representatives from the economic, scientific andpolitical sectors are involved.
In the following the projects with research character are presented which are under way at this stage.
They are partly supported financially by the State Ministry for Education and Research (BMBF) andpartly self-financed:-

Economical wastewater treatment (fine screening) for reuse of the water in agricultural
applications (co-financed by the BMBF). The goal of the project is mechanical water
treatment that produces irrigation water and at the same time recovers the nutrients nitrogenand phosphorus. The realisation of the project takes place in Algeria in close cooperation with
the GTZ and the University of Witten-Herdecke, Prof. Dr. Rudolph (see also chapter 3.1.).

-

Integrated wastewater and waste disposal systems for megacities with anaerobic
treatment for the provision of nutrient-rich water (co-financed by the BMBF). This projectis realised in Lima under the lead management of Prof. Jumar of the IFAK Institute (see also
chapter 3.2).

-

Decentralised underground treatment of heavily polluted precipitation runoffs fromspaces which are for traffic in urban agglomerations (self-financed). This filter system isinstalled at a highly frequented road in Munich and tested by the TU of Munich, Prof. Dr.
Horn.

-

Treatment of greywater with a reduced pollution load in order to produce service waterwith the aim of water reuse for irrigation and as toilet flush water (co-financed by the- 250 -

3
BMBF). This project aims at the Chinese market and is executed by the TU of Darmstadt,
Prof. Dr. Cornel.

3.1-

Production of nutrients and energy from separated individual wastewater flows bymeans of specific treatment of urine, biogas production from faeces and bio-waste,
and production of toilet flush water from greywater (co-financed by the BMBF). The
technical realisation takes place in Vietnam in cooperation with the University of Bonn, Dr.
Clemens.

-

Closing water and nutrient cycles on a regional scale through treatment of wastewaterand separated wastewater flows at source – HUBER ReUse concept with Recovery
Plant and ReUse Park (self-financed). The ReUse Park operated at the company’s
headquarters in Bavaria demonstrates water reuse options. The project proves thatwastewater that has been treated with HUBER technologies (Recovery Plant) can without
problems be used as agricultural irrigation water or even for pond management (see also
chapter 3.3.)

Economical wastewater treatment by means of fine screening
Example: Algeria

Algeria is presently undergoing a far-reaching political and economic transformation process, which
is characterised by a high migration into cities and rapid urbanisation. Especially in the northern partof the country the population pressure on the cities can be observed. Reduction of unemployment
and management of the water supply shortage and wastewater disposal problems are the greatchallenges the local municipality is faced with.
The management of the cities’ water resources is frequently inappropriate. Irrigation of parks withpotable water for example is common practise in the richer districts of Algiers. Vegetable gardens inslums, on the contrary, are irrigated with raw wastewater under totally uncontrolled conditions, which
both increases the environmental burden and leads to health problems.
By irrigating grasslands with partly treated raw wastewater from the sewer system the healthconditions in slums can be improved and the drinking water consumption reduced. Testing a simple
treatment system with mechanical solids separation, sedimentation and UV irradiation is the focus of
the BMBF research project “Decentralised reuse of raw wastewater for grassland development inarid areas” at Algiers. In cooperation with GZT and Prof. Dr. Rudolph (University of Witten/Herdecke,
Germany) HUBER takes part in the project by adapting the newly developed screening machine
HUBER PS Pipestrainer (Fig. 1).

Figure 1: Economical wastewater treatment by means of fine screening for Algier
The aim of the project is to realise a compact, easy to operate and affordable treatment plant for theextensive removal of undissolved pollutants from the raw wastewater and partly inactivation ofgerms, which allows to minimise the hygienic risks when handling treatment equipment. The partly- 251 -

4
treated, nutrient-rich wastewater is planned to be used in a demonstration project for irrigation of test
areas on the premises of the ENSH University in Algier (HUBER Report 2/2006).

3.2

Integrated wastewater and waste disposal systems for megacities withanaerobic treatment
Example: Lima

According to the United Nations’ prognosis, in 2030 approximately five billion people will live inmetropolitan areas. The rapid urbanisation process with its dramatic consequences concerns
especially large cities in emerging and developing countries. One example for this development is
Lima, the fast growing capital of Peru. On the outskirts of the eight million metropolis increasingly
uncontrolled settlement (Fig. 2) takes place with people living under critical conditions, such as lack ofwater and current, education and medical care.

Figure 2: Slum in Lima
The megacity’s growing hygienic, social and ecological problems are frequently too much of achallenge for the local governments. A remedy to the critical situation can in most cases only be
decentralised and specific measures. It is the goal to elaborate adapted strategies also in the field ofwater management, which aim at sustainable onsite recycling management through reuse of waterand nutrients.
Alternative systems for anaerobic treatment of suspended solids from wastewater and organic kitchen
wastes are presently tested within the scope of the BMBF research project “Lima – Megacity ofTomorrow” under the lead management of the Institute for Automation and Communication (IFAK).
Within this project HUBER plans to install in Lima, in cooperation with the Peruvian partners, a twostage biogas reactor which is to be operated under thermophilic conditions.
This anaerobic reactor is planned to be applied within the scope of an overall concept that is adapted
to the city’s specific situation for the integrated treatment of bio-waste and solids contained within
wastewater. The aim of the concept is the recovery of energy-rich biogas and safe fermentation
residues, which as a soil improver can be applied onto agricultural land. The experiences gathered in
the project will serve as the basis for the transfer of adapted technologies to other megacities withsimilar environmental problems (HUBER Report 2005/2006).

3.3

Closing regional water and nutrient cycles near to source
Example: Berching

The HUBER demonstration project, which has been run since January 2006 under the name of“HUBER Reuse Concept”, is considered to be an example of best management practice in the field of
wastewater treatment. Innovative sanitary systems with/without separation are applied at thecompany’s headquarters and different options of reuse of treated wastewater and the nutrientscontained are demonstrated. The goal is to get most of the value out of wastewater by applying- 252 -

5
specifically developed technologies, operated as Recovery Plants, i.e. to recover as many as possibleof the valuable materials – mainly water and nutrients – contained within the separated andunseparated wastewaters produced by the 200 employees and reuse the recovered materials in thecompany’s ReUse Park.
In the HUBER office building yellow water (undiluted urine) and brown water (faeces and toilet flush
water) are collected separately by means of waterless urinals and NoMix toilets, transported inseparate lines and stored separately. Also the greywater (dishwater and washing-up water) flows in a
separate line to the collection tank. Approximately half of the separated wastewater flows is mixed inorder to simulate conventional domestic wastewater. New HUBER technologies are available for the
specific treatment of the separated or partly combined wastewaters, which are operated with the aim
to provide hygienic service water and nutrients for agricultural applications (Fig. 3).

Recovery Plant and ReUse Park

Figure 3: Recovery Plant and ReUse Park at HUBER-

Membrane Bioreactor: The HUBER Membrane Bioreactor system provides for the specifictreatment of the total wastewater, greywater (and black water if required), and produces atthe same time a virtually germ-free effluent, which is reused as irrigation water or feeding of afish pond.

-

Precipitation, stripping and absorption: The combination of precipitation, stripping andabsorption in the new HUBER modules is suitable for treatment of undiluted urine. The aim of- 253 -

6
this process is the recovery of the nutrients phosphorus and nitrogen in the form of solid andliquid fertilisers for plant beds in the ReUse Park.

-

Anaerobic treatment technology: The HUBER anaerobic treatment system produces biogas
from faeces and bio-waste. Due to the high process temperatures an hygienic fermentation
residue are produced, which is used as a soil improver in the orchard.

The aim of the HUBER ReUse Concept is ultimately the sustainable recycling of local water andmaterial flows. The treated wastewaters and value materials contained are reused in the company’spark in order to grow vegetable food for human consumption. By using innovative sanitary concepts
and practising the reuse of water and valuable material contained within wastewater in their own
office building HUBER is contributing to a substantial paradigm shift in wastewater treatment.
Wastewater is no longer considered waste material but valuable raw material for recovery of service
water, nutrients and energy. Particularly semi-arid countries where also the availability of nutrients for
agricultural application is frequently limited will benefit from these new developments in the field of
wastewater treatment (HUBER brochure, 2006).

4

References

Brochure (2006): „HUBER ReUse Concept“, Research and Development, Hans Huber AG, Berching.
BMU: http://www.bmu.de/meeresumweltschutz/kurzinfo/doc/2926.php
Cornel, P. (2004): Wasserresourcen, Wasserbedarf und Möglichkeiten der Wiederverwendung,
Schriftenreihe WAR, Band 159.
HUBER Report 2/2006. Aktuelle Nachrichten für Kunden und Freunde des Hauses HUBER, Hans
Huber AG, Berching (in print).
HUBER Report 2005/2006. Aktuelle Nachrichten für Kunden und Freunde des Hauses HUBER, Hans
Huber AG, Berching.
WHO (2006): “Guidelines for the safe use of wastewater, excreta and greywater”, Volume 2. Wastewater use in agriculture.
WHO/UNICEF (2005): Water for Life – making it happen. WHO/UNICEF Joint Monitoring Programme
for Water Supply and Sanitation.

- 254 -

Hans G. Huber
Karl-Josef Huber
1967

Josef Huber
Master Coppersmith
1948

Hans Huber
Master Coppersmith
1908

Johann Huber
Master Coppersmith
1872

Johann Wöhr
Master Coppersmith
1834

Anton Schreiber
Master Coppersmith
1830

Johann Schreiber
Master Coppersmith
1786

Steel

Copper

Waste
Water

PotableWater

Breweries,
Distilleries

Dr. Stefania Paris
Research and Development
HANS HUBER AG, Berching

Wastewater

Reuse of Treated
Wastewater

10th Japanese German Workshop
Berlin, 10th October 2006

Tradition - Quality - Progress

Stainl. Steel- 255 Potable Water

Breweries, Distilleries

The Quality
Company Worldwide

Conclusions●

Â ServiceÂ Stainless steel

Â Decentralized treatment - reuseÂ Advanced treatment• Systems for sedimentation tanks• Membrane bioreactors• Filtration plantsÂ Sludge treatment• Screening• Thickening and dewatering• Drying and handlingÂ Mechanical treatment• Screenings / grit separation and treatment• Storm water treatment

Business Units and Products

Current research projects on reuse

Reuse of treated wastewater●●

Reasons for alternative solutions

Research and Development●●

Company profile●

Contents

- 256 -y Croatiay Denmarky Hungaryy Japany Koreay Lebanony Malaysia
y Macedoniay Mexicoy New Zealandy Netherlandsy Great Britainy Italyy Polandy Singapore

y Slovakia

y South Africa

y Spainy Swedeny Switzerland

y United Arab. Emirates

y USA

Around 2.6 billion people have to live without sanitary facilities

Approx. 4,500 children die each day of diseases caused by dirty
water

●

●

Most people will live in the mega cities

Wider agricultural areas will be needed for covering the increasedfood demand and so more water will be required●●(UN, 2005)

The world population will increase to 9 billions until 2050●

Tomorrow

About 1.1 billion people do not have access to clean drinking water●(WHO/UNICEF, 2005)

Approx. 6.5 billion people live nowadays on earthy Ukrainey Turkeyy Thailand

y Taiwany Sudany Slovenia

y Saudi Arabia

y Russiay Romaniay Portugal

●

Today

Actual Situation and Prognosis

y Chiley Francey Belgiumy Norwayy Chinay Brazily Australia

y Greecey Bulgaria

y Czech Republic

y Argentina

y Finlandy Austria

Representatives

Sales Offices

Subsidiaries

Headquarters and Production in Berching, Germany

Global Presence

Water Scarcity: less than 1,000 m3/(Ca⋅a)

Water Stress: 1,000 to 1,700 m3/(Ca⋅a)Freshwater Stress

Wastewater is asource of water,
nutrients and energy !

Our Target…
…Solutions for the Future !

Development of innovative technologies
Research on alternative solutions for reuse● Cooperation with the university●●

Research and Development

- 257 -Some figures:y USA
y Japany Italyy India

350 l/(Ca•d)319 l/(Ca•d)249 l/(Ca•d)
25 l/(Ca•d)For example Germany: 127 l/(Ca•d)

Water Consumption in Household

Water Reuse / Nutrient Reuse⇒ Alternative solutions are needed !

(ATV, 2004; bfai, 2005)…The use of wastewater in agriculture can help communities togrow more food and make use of precious water and nutrient
resources. However it should be done safely to maximize publichealth gains and environmental benefits…
(WHO Guidelines, 2006)(approx. 20%)(> 70%)(approx. 10%)HOUSEHOLD

Medicineso not present++ moderate present+
barely present+++ strong present

+

41 %

++

30 kg/(Ca*a)

COD

34 %

++

1,8 kg/(Ca*a)

K

10 %

3%

27,000Grey water

+++

+

12 %

54 %

50 %

87 %

500

Yellow waterBlack water

Grey water+++

0,75 kg/(Ca*a)P

Pathogenic
bacteria

4-5 kg/(Ca*a)42,000

Domestic
wastewaterN

Amount l/(Ca*a)Parameter

Domestic
wastewater

+

+++

47 %

12 %

40 %

10 %

50

FaecesYellow water

Brown water(Otterpohl, 2001)

o

o

0%

0%

0%

0%

14,000

Flushing
water

Domestic Wastewater Flows and Components

INDUSTRYAGRICULTURE

billion m3…Between 1990 and 2004, sanitation coverage in the developingworld increased from 35 to 50 per cent. This meant that 1.2 billion
people gained access to sanitation during this period. Another 300
million people should have been served, however, to keep the world
on track towards the 2015 target... (MDGs Report, 2006)

Increase of the worldwide water consumption

Halve, by 2015, the proportion of people without sustainable
access to safe drinking water and basic sanitation.

Water Consumption of Each Sector

Target (MDG: Johannesburg, 2002)

MDGs and Alternative Solutions

- 258 -Operation of lakes and ponds

Artificial ground water recharge●●

Effluent for
Reuse

55
85
80

130
100

Corn
Grassland

205

200

65

K2O
Ca
32
49
46

Ca
23
25
19

Pre-treatment with screening (HUBER Ro2)
Sedimentation pond
Storage and stabilization in deep reservoir

HUBER
Wedge Section
ScreenWastewater

Anaerobic Lagoons,
Oxidation Ponds,
Aerated Lagoons, etc.
Storage andStabilization in DeepReservoir ≥ 6 m

Min. Level (End of
Irrigation Season)

Max. Level (Beginningof Irrigation Season)(Usually by
Drip Irrigation)(modified according to Libhaber, 2004)⇒ CSB-reduction and hygienisation !

●

●

●

Treatment steps:

25

32

30

Ca

106

113

70

Ca

186

186

60

Ca

Semi-central treatment of greywater for production of service
water, Darmstadt and afterwards China
Onsite treatment of separated wastewater flows for closing thewater and nutrients loop, Berching and Vietnam●

Decentralized treatment of runoff from roadways for ground water
recharge, Munich
●

●

68

73

47

Ca

Integrated wastewater and waste disposal systems for mega cities
with thermophilic digestion of primary sludge and biowaste, Lima

Treatment of Separated Wastewater Flows●

Economic decentralized treatment of wastewater with finescreening for irrigation, Algeria

Treatment of Municipal Wastewater and Sludge
●

22

28

26

Ca

141

138

45

Ca

Black water(Bundesministerium für Land und Forstwirtschaft, 2005)

114

111

36

Ca

Yellow water

Required number of capita for the use ofWastewater* according to the guidelines for proper fertilization

P2O5

N
120

(kg/ha)Nutrient
requirement*

Wheat

Plant

Reuse of Water and Nutrients

Settlements- Flushing toilets- Washing laundry- Use as fire water- Use for air conditioning●

Current R&D Projects

Irrigation of parks●

Nutrient Requirement and Covering Possibility
Nutrient requirement of different plants and required amount (as capita) of different
wastewater flows for covering this nutrient requirement

Simple Treatment of Municipal Wastewater for Irrigation

Irrigation in agriculture

●

●

●

Removal of particulate substances
No elimination of nutrients● Disinfection

Goals of Wastewater Treatment

Agricultural Utilization

Real application for Jerusalem, Israel

Industrial processes●

Depending on water quality, the reuse of treated wastewater
is suitable for:

Reuse of Treated Wastewater for
Reduction of Freshwater Consumption

- 259 -Pre-treatment with fine screening (HUBER Pipestrainer)
Sedimentation
Disinfection with UV

LiquidIrrigation

Notüberlauf

Schlammfang
Schachtunterteil

Schachtring mit
Zykloneinsatz

Schachtring

ZulaufTragschicht

Einlaufelement
mit Grobfilter

Speicher/Ablaufleitung

Ablauf

Detailskizze haufwerksporige Rinne

Rinne

Cooperation with Prof. Horn, Technical University of Munich - Self financed

Trichter für
Schlammfang

Absaugrohr für
Schlamm

HUBER
Edelstahlfilter mit
variablen Füllungen

GehwegFahrbahn

Filtration through porous concrete
Sedimentation
Filtration through different materials (HUBER Hydro-Filt)⇒ Retention of heavy metals and PAHs!

●●●

Treatment steps:

Precipitation/Flocculation

Dosing Station

Screenings

HUBER
Microscreen

Storage

SurplusSludgeHUBER Membrane
Bio-Reactor

UVDisinfection

Cooperation with Prof. Cornel, Technical University of Darmstadt - Co-financed by the BMBF (50%)

Grey Water

HUBER
Sand Filter● Microscreening (HUBER RoDisc)● Sand filtration (HUBER ContiFlow)● Activated sludge with membrane filtration (HUBER MCB)

Comparison of different treatment combinations:

Outflow

Outflow

Fermentation
Residue for Soil
Conditioning

Outflow for Soil
Conditioning

Biogas for Energy andHeat Production

Reuse for Toilet Flushing

Aerobic
Treatment

Reuse for Artificial Ground Water Recharge

HUBER
Thermophilic
Biogas Reactor

Sedimentation

Semi-central Greywater Treatment, Darmstadt

Existing Sewer System

Irrigation ofGreen

Municipal Wastewater(after screen 6 mm)

Treatment of Runoff from Roadways, Munich

SludgeUV-Disinfection

Container

Cooperation with Prof. Jumar, IFAK - Co-financed by the BMBF (50%)

Screenings

LiquidSedimentation

Mechanical pre-treatment with screening
Sedimentation
Thermophilic digestion (HUBER Biogas Reactor)⇒ Reduction of organic substrate and hygienisation !

●

●

●

Cooperation with Prof. Rudolph, University of Witten/Herdecke - Co-financed by the BMBF (50%)

Wastewater

HUBER
Fine Screen⇒ Reduction of suspended solids and hygienisation !

●

●

●

Treatment steps:

Reuse of Biogas and Digested Sludge

Reuse for Irrigation of Green

Primary Sludge

Treatment steps:

Thermophilic Digestion of Sludge in Lima

Economic Treatment of Wastewater in Algeria

wash water- 260 -Unseparated wastewater
Grey, yellow and brown water

Utilization of treatedwastewater and nutrients--

Implementation of alternative
treatment technologies

Productionof food in the
ReUse Park

Recovery of waterand nutrients in the
Recovery Plant

Agri-Park

Agri-Park

Aqua-Park●

Aqua-Park

Irrigation of green with treated wastewater
Fertilization of crop fields and fruit trees withnutrients from wastewater●●

Feeding a fish pond with treated grey water
Operation of a fish pond with ground water(HUBER Brochure, 2006)●

HUBER ReUse Park

Own project - Self-financed⇒ Closing the material and water loop!

●●

Goal: to get most of the value out of wastewater !

An Example of “Good Management Practice”

y Rainwatery Grey, Yellow and
Brown Watery Unseparated
Wastewater

Closing the Loop

Recovery Plant

Wastewater:
Wastewater:a Source

Service water
Nutrients

Infiltration

ReUse
Park

Vegetable andanimal food- Recovery Plant and ReUse Park -HUBER ReUse Concept
Wastewater a Source for Water, Nutrients and Energy

HUBER ReUse Concept in Berching- 261 -Service water, nutrients and energy can begained from wastewater and its separated
flows

The quality request for treated wastewater
depend on the specific reuse option

A sustainable resource management
should be achieved through substitution of
fresh water and mineral fertilizer

The agricultural utilization of treatedwastewater is a reasonable practice forarid and semiarid regions

●

●

●

●

(Press release, DBU)

Hans G. Huber receives the highest endowed
European environmental award for outstandingachievements in global environmental protection
for his great commitment to developing and successfully promoting highquality, reliable technologies for fresh water and wastewater treatment,
especially also in emerging and developing countries.

The Deutsche Bundesstiftung Umwelt (DBU), oneof Europe's largest foundations that promotes
innovative and exemplary environmental projects,
awards the Deutschen Umweltpreis 2006 (German
Environmental Award 2006) to Hans G. Huber,
member of the board of directors of the Hans
Huber AG, for his innovative decentralised wastewater treatment technology.

German Environmental Award 2006
October 27, 2006

Wastewater is valuable resource!

The application of the right technology
enables to get most of the value out of
wastewater●

Conclusion

Thank you for your attention !

Research and Development of
Innovative Water Technologies

European Water
Partnership

European Academy of
Sciences and Arts

International Water
Association

Obligation of the water profession for our common future“Water Supply and Sanitation for All”

on

Conference Center, Berching - September 27-28, 2007

3rd International Huber Symposium

Wastewater - A Source !

HUBER Solutions – Technologies for Water !

- 262 -Environmental Protection Agency (EPA, 2004)
Guidelines for Water Reuse- mikrobiologische und physisch/chemische
Anforderungen

Food and Agriculture Organization (FAO, 1994)
Water Quality for Agriculture - Irrigation and Drainage Paper- physisch/chemische AnforderungenStaatliche, regionale bzw. lokale Vorschriften

●

●

●

Treatment of combined sewage with a chemical andmechanical system, prevention of water pollution in
BerlinCo-digestion of septic sludge and biowaste in semicentral plants, IWRM on Java

Specific treatment of yellow- and brown water at GTZ
building, alternative sanitary system in Eschborn

Wastewater treatment with the MBR process, artificial
groundwater recharge in the Jordan Valley

●

●

●

●

Further Projects Applied for Financing

World Health Organisation (WHO, 2006)
Guidelines for the safe use of wastewater, excreta andgreywater- Risikobewertung (DALY-Konzept)●

Standards und Vorschriften

●

●

●

Small compact filtration unit
Production of high quality outflow

Recovery of phosphorus and nitrogen in the form of fertilisers---

2-step anaerobic thermophilic reactor
Production of biogas and high quality fermentation residue

for faces and biowaste

Biogas Reactor (HUBER 2T-BioR)

2-step chemical-physical process-

for yellow water

Precipitation Reactor, Stripping&Absorption Column(HUBER NuRec and NitriRec)--

for wastewater, black and grey water

Membrane Bio-Reactor with HUBER MCBs

HUBER Technologies of the Recovery Plant

WHO (2006): “Guidelines for the safe use of wastewater, excreta andgreywater”, Volume 2. Wastewater use in agriculture.

Paris und Wilderer (2002): „Integrierte Wasser Ver- und Entsorgungskonzepte im internationalen Vergleich“, in: 35. Essener Tagung (M.
Dohman, ed.), Vol. 188, 45/1-15.

Otterpohl (2001): „Stand der Technik und Entwicklungen für den urbanen
Bereich“, in Berichte aus Wassergüte- und Abfallwirtschaft, TU München,Band 161.

Hans Huber AG (2006): Brochure „HUBER ReUse Concept“, Research andDevelopment, Berching.

DWA (2004): Brochure „Facts and Figures on the Subject of Water“,Publisher: DWA German Association for Water, Wastewater and Waste,
Hennef.

Cornel und Weber (2004): „Erzeugung von Bewässerungs-wasser durcheine chemisch physikalische Abwasserbehandlung“, 73. Darmstädter
Seminar, TU Darmstadt, Band 159.

References

ESTABLISHMENT OF GUIDELINES FOR THE REUSE OF
TREATED WASTEWATER
A. Tajima*,

M. Yoshizawa**,

K. Sakurai**, and

M. Minamiyama*** Sewerage and Wastewater Management Department, Ministry of Land, Infrastructure andTransport (MLIT).
** Wastewater and Sludge Management Division, Water Quality Control Department, National
Institute for Land and Infrastructure Management (NILIM), Ministry of Land, Infrastructure andTransport (MLIT). Asahi 1, Tsukuba, Ibaraki 305-0804, Japan.
Abstract: The Committee on Reclaimed Wastewater Quality Criteria (Chairman: Dr. Mitsumi Kaneko,
Visiting Professor of Ritsumeikan University) established new criteria and considerations for the reuse oftreated wastewater such as toilet flushing water, sprinkling water, water for landscape use and water forrecreational use. To establish new criteria and considerations, hygienic safety of users, appearance andacceptance of users, and risk of facility malfunction were discussed. The new criteria and considerations
were published as the Guidelines for Reuse of Treated Wastewater from the Ministry of Land, Infrastructure
and Transport in Japan. In the guidelines, new criteria were established for Escherichia coli (N.D. /100mL)
instead of coliform groups in the former guidelines with the exception of reuse as water for landscape use.
Facility standards including required treatment methods and turbidity as the index used for ensuring effective
treatment were also established. In addition, measures against loss of residual chlorine, cross connection,
and accidental intake were established as considerations for treated wastewater reuse.
Keywords:

reclaimed wastewater quality standard, treated wastewater reuse.

Introduction
Japan¶s average annual rainfall is approximately 1,700mm, which is twice the world average, but
because of its small land area and large population, the annual per capita water resource is about
3,300m3, less than half the world average 7,800m3. There is only 905m3 (almost same as Egypt)
available in the Kanto district where Tokyo is located. Furthermore, the precipitation has been
fluctuated greatly in recent years. For these reasons, more importance is now placed on managing
water resources in Japan (MLIT, 2005a).
In response to the severe water shortage of 1978, Japan began to reuse treated wastewater asimportant water resources in urban areas, starting with reuse for toilet flushing in Fukuoka City in
1980. Since then, treated wastewater has also been used for snow melting, environmental andindustrial use, sprinkling and so on. However, only 200 million m3 per year of treated wastewater of
246 wastewater treatment plants (WTPs) has been reused outside the plants, which is less than 2%of the 1.4 billion m3 of effluent from 1,924 plants in FY 2003 (JSWA, 2005). It is expected thatsuch applications will increase in the future from the viewpoint of saving water resources in urban
areas, which will in turn increase the importance of appropriately reusing treated wastewater.
On the other hand, since some cases of the human health damages by the pathogenic microbes
have reported in recent years in Japan, many people have become interested in hygienic safety ofwater. Therefore, measures against these new problems must be taken from now on when we
10th Japanese German Workshop on Wastewater and Sludge Treatment, Berlin, Germany.

- 263 -

2

10th Japanese German Workshop on Wastewater and Sludge Treatment, Berlin

promote reuse of treated wastewater. In addition, it is necessary to maintain an appropriate color,
clearness, and less odor of the reclaimed wastewater to ensure that the public feels comfortableusing as well as protecting against facility malfunctions such as corrosion and blocking of pipes.
For the above reasons, the Sewerage and Wastewater Management Department, Ministry ofLand, Infrastructure and Transport and the Water Quality Control Department, National Institute forLand and Infrastructure Management formed the Committee on Reclaimed Wastewater Quality
Criteria (Chairman: Dr. Mitsumi Kaneko, Visiting Professor of Ritsumeikan University) with theobjective of establishing new guidelines for the reuse of treated wastewater. The Ministry of Land,
Infrastructure and Transport instituted the new criteria and considerations proposed by thecommittee as the Guidelines for the Reuse of Treated Wastewater (MLIT, 2005b) and announced itin April 2005. This report presents an outline of the guidelines.

The scope of applications to use the treated wastewater in theguidelines
Because there were many kinds of applications to use the treated wastewater, we could study
limited applications to use on the basis of the actual conditions of treated wastewater reuse in Japan.
In the guidelines, toilet flushing, sprinkling, landscape use (untouchable) and recreational use(touchable) could be considered. These applications were usage for many and unspecified persons
and the reclaimed wastewater was distributed directly from WTPs. Sprinkling refers for watering totrees, plants and lawns or for road flushing. Landscape and recreational use refers for environmental
water.
For the time being, we decided to consider that reuse as large-scale waterfalls or fountains wererecreational use, because they might produce mist.

Actual conditions of the complaints and problems concerning treatedwastewater reuse in JapanThe new guidelines were established from three points of view: hygienic safety, appearance andacceptance, and risk of facility malfunction. Details of the guidelines concerning appearance andacceptance, and facility malfunction were based on a study concerning complaints and problems on
actual treated wastewater reuse in Japan. The outline of the study is as follows.
Methods
Questionnaires were sent out to WTPs that distributed reclaimed wastewater outside themselves in
FY 2002 as toilet flushing water, sprinkling water, water for landscape use, and water forrecreational use. The results of this research enabled us to know the details of the complaints andproblems regarding treated wastewater reuse in the past.

- 264 -

Establishment of guidelines for the reuse of treated wastewater

3

Results
We obtained the following information as a result of the study.
Appearance and acceptancex

Appearance of reclaimed wastewater
Reclaimed wastewater is generally inferior to drinking water in color, clearness and odor, so
these problems must be considered. There were complaints about the appearance of toilet
flushing water but few complaints about other uses, most likely because people had more
opportunity to observe the toilet flushing water.

x

Growth of periphytic algae where the treated wastewater are used as water for landscape use
and water for recreational use
Reclaimed wastewater generally contains more nutrients such as nitrogen and phosphorus
than drinking water. Nutrients accelerate the propagation of periphytic algae. These algae
lead complaints from user of the facilities.
Chironomid in toilet flushing water
There were complaints concerning the growth and propagation of Chironomid in thereservoir tank or toilet flushing water after being distributed from the WTP to the place ofuse. On the other hand, there were few complaints about this problem in landscape use andrecreational use water because Chironomid scatters easily and is not as prominent.

xFacility malfunction
Problems concerning corrosion and leaking of pipes and other equipment were reported. The
corrosion may be caused by the direct contact between the reclaimed wastewater and exposed ironor between different kinds of metals. Attention must be paid to corrosion in case of highly corrosive
reclaimed wastewater with significant amounts of chlorine ion, sulfate ion, or residual chlorine.
Troubles of water supply due to the blockage of drains or bended points of the pipes werereported, also. Blockage of pipes may occur because the dissolved iron from corrosion is oxidized
by residual chlorine or dissolved oxygen and stored at the bended points or narrow areas of thepipes. Measures have already been taken against these problems and they have now been solved(Fukuoka city, 1999; Fukuoka city, 2000).

The guidelines for the reuse of treated wastewater
The guidelines are divided into two parts such as criteria for wastewater reuse and considerations
for wastewater reuse. They were established from three points of view: hygienic safety, appearance
and acceptance, and risk of facility malfunction. The outline of the guidelines is as follows.

- 265 -

10th Japanese German Workshop on Wastewater and Sludge Treatment, Berlin

4

Three points of view to establish the guidelines
Hygienic safety
To establish the guidelines, measures against the bacteria which chlorine was comparatively
effective and protozoa which comparatively had the chlorine tolerance were considered.. Measuresagainst viruses could not be considered because of the numerous problems in the detection methodsof viruses.
Appearance and acceptanceThree points listed below were considered to establish the guidelines. The second and third points
were considered only in the considerations for wastewater reuse, not in the criteria part, because
different types of facilities caused different conditions for the second point and the effects ofmeasures have not been clarified for the third point.
x Appearance of reclaimed wastewater (color, clearness, odor)xx

Growth of periphytic algae in facilities landscape use and recreational use water
Chironomid (imago/larva) in toilet flushing water

Facility malfunction
Measures against corrosion and blockage of pipes and other equipment were considered to establish
the guidelines.
New criteria for treated wastewater reuse
The new criteria established for the reuse of treated wastewater are shown in Table 1. The grounds
for the new criteria are indicated as follows.
E.coli and Coliform groups
These criteria were selected from the viewpoint of measures against bacteria.
E.coli N.D./100mL was set as a new criterion instead of number of coliform groups. The numberof coliform groups, which includes bacteria that propagates in soil, is not necessarily suitable as theindex for indicating contamination by excrement. Furthermore, E.coli N.D./100mL was set as thequality criteria for drinking water in Japan in 2003 on the basis of establishing a quick and easy
culture method.
The number of coliform groups set as effluent quality criteria was established as a provisional
criterion for landscape use, where handling is not permitted, and the former criteria for the treatedwastewater reuse (coliform groups 1,000CFU/100mL) was adopted on a provisional basis.
Facility standards (Required treatment methods and Turbidity as control parameter of the
facility)
The facility standards were established from the viewpoint of measures against facility malfunction
and protozoa for hygienic safety.

- 266 -

Establishment of guidelines for the reuse of treated wastewater

5

Designated treatment methods and turbidity conditions were set from the viewpoint of protecting
against blockage for toilet flushing, sprinkling and landscape use, for which there is little possibilityof accidental intake. Sand filtration or an equivalent treatment method was required as the facility
standard. Turbidity was also set as the control parameter to ensure effective treatment of the sandfiltration. Turbidity of less than 2 mg-kaolin equivalent/L was set as the target value on the basis ofresearch results demonstrating that turbidity of the treated wastewater from a properly operated
filtration system hardly exceeded 2 mg-kaolin equivalent/L.
Chemical precipitation followed by sand filtration or an equivalent treatment method wererequired as the facility standards to efficiently remove protozoa from recreational use water forwhich there is a risk of accidental intake. Turbidity of less than 2 mg-kaolin equivalent/L was set.
Additional treatment, restricted use or stop of distribution of treated wastewater may be requiredin cases if hygienic safety is at risk due to a group infection outbreak caused by protozoa within thebasin of the WTP.
pH
The pH level of 5.8-8.6 was set as an effluent quality criterion. It was established from theviewpoint of preventing corrosion in pipes or other equipment. In addition to this, it wasrecommended that corrosion-resistant structure and materials for pipes or other equipment should
be adopted.
Appearance, Color, and Odor
Appearance, color and odor were established from the viewpoint of appeal and acceptance. These
criteria were same as the former criteria. The target value of the color in the former criteria was set
based on the results of user questionnaires in which almost all users accepted the color of 40 units
under the premise of not handling the water and the color of 10 units under the premise of handling(JSWA, 1981; MOC et al., 1990). However, it is preferable that the values should be set based on
the regional users¶ wishes.
Residual chlorine
In terms of controlling bacterial growth in the distribution process, chlorine disinfection with longterm effects was regarded as the basic disinfection method and the concentration of residual
chlorine was set as the target value. The concentration of residual chlorine set as the drinking water
quality criteria in Japan (free: more than 0.1mg/L or combined: more than 0.4mg/L) was applied tothe criteria for treated wastewater reuse. It was also, based on the results of research indicating thatbacteria hardly developed in the distribution process under conditions of values greater than
0.1mg/L for free residual chlorine or 0.4mg/L for combined residual chlorine.
For sprinkling and recreational use of treated wastewater, the value was not applied for cases inwhich long- term effects of disinfection are not required., for example, when the retention time fromthe WTP to the place of use is short.

- 267 -

10th Japanese German Workshop on Wastewater and Sludge Treatment, Berlin

6

A value was not set for landscape use because handling is not permitted in its use and treatment
except chlorine disinfection may be adopted from the viewpoint of ecosystem preservation.

Table 1 ± New criteria for reuse of treated wastewater in JapanE. coliAppearance
Turbidity
Color
Odor
pH
Residualchlorine

Treatment

Standards
applying
location
Outlet ofthereclaimed
treatment
facilities

Toilet flushingwater

Sprinkling water

N.D./100mL

N.D./100mL

Water forlandscape use

Water forrecreational use

҇
1000CFU/100m
L as coliform
groups1)

N.D./100mL

Not unpleasant
҇ 2 2)3)
҇ 40 units

Administr
ationboundary

Not unpleasant
5.8 - 8.6
҈ free: 0.1mg/L
orcombined:
0.4mg/L 2)

҈ free: 0.1mg/L
orcombined:
0.4mg/L2)4)

Sand filtration or equivalent

҇ 23)
҇ 10 units

҈ free: 0.1mg/L
orcombined:
0.4mg/L2)4)
Chemicalprecipitation +sand filtration
or equivalent

1) Provisional value2) Control target value3) Unit: mg-kaolin equivalent/L
4) Not applicable for cases in which long-term effects of disinfection is unnecessary

Considerations for treated wastewater reuse
The main considerations for treated wastewater reuse are given below.
Measures against loss of residual chlorinexx

Decrease, as much as possible, in ammonia nitrogen that easily consumes residual chlorine
using the secondary treatment and reclamation treatment.
Construct distribution networks so as to shorten the retention time. For example, theselection of pipes with suitable diameter and the avoidance of dead ends by looping of pipes.
Also pipes should be used to the material not easily oxidized by residual chlorine.

x

Consider additional chlorine disinfection in places where residual chlorine is significantly
decreased.

x

Confirm of suitable volume of the reservoir tank in facilities where reclaimed wastewater isused, and cleaning of the tank to control the consumption of residual chlorine.

Measures against cross connectionx

Indication of treated wastewater by placing signs on pipes and other equipment or colorcoding them in order to clearly distinguish ones using reclaimed wastewater. An example ofcolor-coding is given as Photo 1.

- 268 -

Establishment of guidelines for the reuse of treated wastewaterx

7

Inspection for cross connections before starting the distribution of reclaimed wastewater. The
sewerage administration departments must confirm that there is no cross connection. One
example of inspecting for cross connection is opening and shutting the main valves for thereclaimed wastewater and the drinking water after coloring the reclaimed wastewater.

Measures against accidental intakexx

Posting of notices to users that reclaimed wastewater is used. Especially in the case oflandscape use, accidental intake must be prevented by displaying explicit warnings against
drinking.
Regarding sprinkling, accidental intake of the mist can be prevented, for example, bysprinkling at a time when there are few people in the area.

Photo 1 - Example of distinction by color-coding the pipes (Yellow is reclaimed wastewater, blue is drinking
water)

Conclusion - amendment of sewerage lawThe new criteria and considerations were published as the Guidelines on Reclaimed Wastewater
Quality Criteria from the Ministry of Land, Infrastructure and Transport in Japan. The guidelines
were used as reference for the amendment of the Sewerage Law.
The objective of the Sewerage Law (enacted in 1958) is to develop sewerage systems, thereby
contribute to sound urban development and enhancement of public sanitation, and contribute towater quality control of public water bodies.
Last amendment of the Sewerage Law in October 2005 (enforced in April 2006) newly added thecriteria for the hygienic safety of recreational water in order to preserve living environments and- 269 -

8

10th Japanese German Workshop on Wastewater and Sludge Treatment, Berlin

protect human health. Specifically, under the structural standards for sewerage system facilities
stipulated by the Sewerage Law, in principle, shielding and fences are installed and other measurestaken to prevent entry to the facilities, but it is also stipulated that their installation is unnecessary
under specified conditions. One such specified condition is that the recreational water that is usedsatisfies quality standards for final effluent, contains E.coli N.D./100mL, and has turbidity of lessthan 2mg-kaolin equivalent/L.
New structural standard not only encourages the suitable reuse of treated wastewater, but will
also encourage the recovery of good quality waterside spaces in urban areas.
Acknowledgements
The new criteria and considerations for treated wastewater reuse described in this paper were proposed by theCommittee on Reclaimed Wastewater Quality Criteria. We express our deep appreciation to the members of thecommittee who put extensive effort into developing and proposing the guidelines.

References
Fukuoka city (1999). Syuugou-juutaku-niokeru Saiseisui-riyou-nitsuite (Teigen) (in Japanese) (Suggestions on Treated
Wastewater Reuse in Apartment Houses), Consultation on Treated Wastewater Reuse in Apartment Houses,
Fukuoka City, Fukuoka, Japan.
Fukuoka city (2000). Syuugou-juutaku-niokeru Saiseisui-riyou-setsubi-kijun-ni-tsuite (Teigen) (in Japanese)(Suggestion on Equipment Criteria for Treated Wastewater Reuse in Apartment Houses), Study Conference on
Equipment Criteria for Treated Wastewater Reuse, Fukuoka City, Fukuoka, Japan.
JSWA (Japan Sewage Works Association) (1981). Gesuisyorisui Junkan-riyou Gijutsushishin-(an) (in Japanese)(Technical Guidelines on Reuse of Treated Wastewater - Proposal). JSWA, Tokyo, Japan.
JSWA (Japan Sewage Works Association) (2005). Heisei-15-nendo-ban Gesuidou Toukei (in Japanese) (Statistics on
Sewage Works, fiscal 2003 edition), JSWA, Tokyo, Japan.
MLIT (Water Resources Department, Land and Water Bureau, Ministry of Land, Infrastructure and Transport, Japan)(2005a). Heisei-16-nendo-ban Nippon-no Mizushigen (in Japanese) (Water Resources in Japan, fiscal 2004
edition), MLIT, Tokyo, Japan.
MLIT (Ministry of Land, Infrastructure and Transport, Japan) (2005b). Gesui-syorisui-no Sairiyou Suishitsukijun-tou
manyuaru (in Japanese) (Guidelines for the Reuse of Treated Wastewater), MLIT, Japan.
MOC (Ministry of Construction, Japan) and TCAWT (Technical Conference on Advanced Wastewater Treatment)(1990). Gesuisyorisui-no Syuukei Shinsui Riyou Suishitsu-kentou-manyuaru-(an) (in Japanese) (Manual on Setting
Up of Water Quality Target for Treated Wastewater Reuse such as the Water for Landscape Use and Water for
Recreational Use - Proposal), MOC and TCAWT, Japan- 270 -

Propose guideline(Chairman: Dr. Mitsumi KANEKO,
Ritsumeikan University)

Field survey Committee on Reclaimed
Wastewater Quality Criteria

3

Announcement of guideline to sewage works
administrator

Water Quality Control Department

Infrastructure Management,

National Institute for Land andSewerage and Wastewater
Management Department

Ministry of Land, Infrastructure
and Transport (MLIT)- Local community/municipality- Japanese Institute of wastewater engineering
technology joint research project

2. Framework of Establishment

M. YOSHIZAWA, K. SAKURAI, and M. MINAMIYAMA
Wastewater and Sludge Management Division,
National Institute for Land and Infrastructure Management,
Ministry of Land, Infrastructure and Transport

TAJIMA Atsushi
Sewerage and Wastewater Management Department,
Ministry of Land, Infrastructure and Transport.

ESTABLISHMENT OFGUIDELINES FOR THE REUSE OF
TREATED WASTEWATER

10th Japanese German Workshop on
Wastewater and Sludge Treatment
Oct. 10, 2006. Berlin.

1. Introduction

0

5000

10000

15000

20000

25000

FY

88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03
19 19 19 19 19 19 19 19 19 19 19 19 20 20 20 20

Toilet flushing

Supplying to industrial sites

Supplying to business sites

Agriculture use

Environmetal use

Spraying use

Melting snow

The yearly change in volume of reuse (1988-2003)

186 million m3 (FY2003) = 1.4% of the total treated wastewater
246 treatment plants (FY2003) = 13% of the total treatment plants

3. Present status of treated wastewaterreuse in Japan (1)Three points of view- hygienic safety- appearance and acceptance- risk of facility malfunction

Field survey

42(hygienic safety of reclaimed wastewater)

New Guidelines (2005)

Review the guideline…

Importance of appropriate use of treated wastewater

Outbreak of Cryptosporidium disease (1996) etc.

Importance of hygienic safety of water

Decrease of the rainfall in drought years

Annual per capita water resources - 3,300m3 (Japan) / 7,800m3 (world average)

Importance of saving water resources in urban areas

Volume of reuse（10,000m3／year）- 271 -

- 272 -Supplying to business sites

Supplying to industrial sites

Agriculture use

Spraying use

Melting snow

River maintainance use

Recreational use

Landscape use

Toilet flushing

0

3

9

23

31

40

51

60

100

（処理場数）
Numberof WTP

80

74

120

140

4. Scope of application (1)

20

16

43

図 用途別有効利用処理場数（平成１５年度実績）

Number of treatment plants (FY2003)

160

157

5

180

Toilet flushing(trees, plants, lawns, road flushing)Sprinkling
7- Applications for many and unspecified persons- Reclaimed wastewater that was distributed directlyfrom Wastewater Treatment Plants

用
途
名
称

Purpose of use

3. Present status of treated wastewaterreuse in Japan (2
(2)

用
途
名
称

Agriculture use

Spraying use

Melting snow

River maintainance use

Recreational use

Landscape use

Toilet flushing

Supplying to business sites
0

44

344

1,000

2,089
2,000

3,000

4,000

3,814

（給水量：万m3／年）
Volume of reuse(10,000m3/year)

1,487

用途別有効利用量（平成１５年度実績）

4,567

5,000

6

5,366

8

* Including large-scale waterfalls or fountains
that may produce aerosol(Environmental use)

Recreational use(Environmental use (untouchable))Landscape use

4. Scope of application (2)

389

545

図

Volume of reuse of wastewater (FY2003)

3. Present status of treated wastewaterreuse in Japan (3)Supplying to industrial sites

Purpose of use

6,000

- 273 -

9

pH

Notes

free: 0.1mg/L or
combined: 0.4mg/L3)

Residual chlorine(target value)N.A.

free: 0.1mg/L or
combined: 0.4mg/L3)

Coagulation andsand filtration

10 or less

111) Provisional criteria
2) Unit: mg-kaolin equivalent/L
3) Not applicable for cases in which long-term effects of disinfection is unnecessary

Sand filtration

free: 0.1mg/L or
combined: 0.4mg/L

40 or lessNot unpleasant

N.A.

Treatment

Odor

Color

Not unpleasantAppearance

2 or less2)

N.D./100mL

Total coliforms
10CFU/mL 1)

5.8 - 8.6

N.A.

N.D./100mL

Recreational use

Landscape use

2 or less (target value) 2)

N.D./100mL

SprinklingpH

Turbidity

E.coliToilet flushing

7. New criteria for treated wastewaterreuse- Not establishment of identification and culture of virus- PCR is not enough to evaluate infectiousness- Fate of virus should be further investigated- Dose/response model is to be developed for some species- Resistance to disinfection is not sufficiently clarified/evaluated yet.

Odor

-

-

5.8 - 8.6

10 or below

5.8 - 8.6

Not
unpleasant

10 or below-

Not
unpleasant-Not detective

10 or below

5.8 - 8.6

Not unpleasant

10 or below

40 or below--

1,000 or below(cfu/100mL)

10

3 or below

5.8 - 8.6

Not unpleasant

5 or below

10 or below--

50 or below(cfu/100mL)

12

For landscape use, tentatively same as previous (Coliform groups 10CFU/mL)
because handling not permitted and effluent criteria set as coliform group

However,

No detection in 100mL, new criteria

N.D. of E-coli in 100mL in drinking water by establishing a quick andeasy culture method

Coliform groups not suitable as the index of contamination by excrement

E-coli (Coliform groups)

8-1. Grounds for the new criteria (1)Note : * combined residual chlorine, ** restricted human contact, *** limited human contact

BOD (mg/L)

5.8 - 8.6

Not
unpleasantNot
unpleasant

Turbidity (mg-kaolin
equivalent/L)* Not cover criteria for viruses for following reasons in this new guidelines

Yes

Pathogenic microbes (bacteria, protozoa) *-Not
unpleasant

0.4 or over-Not
unpleasantTrace amountColor (color unit)

Hygienic
safetyYes

Corrosion and blockage of pipes and otherequipment

Appearance

Not detectiveNo

10 or below(cfu/mL)

Outbreak of Chirnomid (imago/larva) (toilet

flushing)

Coliform group

No

Growth of algae (Landscape use, Recreational use)
Chlorine Residual(mg/L)*(proposed in 1990)
LandscapeRecreationaluse**
use***

Yes

Appearance (color, clearness, odor)

Facility
malfunction

AppearanceandacceptanceWorking group composed of Ministryof Construction and some big cities(proposed in 1981)
ToiletSpraying
Landscapeflushing useuseuse

Details
Japan Sewage Works Association

6. Previous guidelines/standards for treatedwastewater use (Reference)

Standar-dization

5. Details of the examination

- 274 -Corrosion control / same as previous (pH: 5.8 - 8.6)

It is preferable to give criteria considering the regional uses’ wishes

However,

10 units or less (Recreational use))

Appeal and acceptance / same as previous(Appearance, Odor: Not unpleasantColor: 40 units or less (Landscape use),

Appearance / Color / OdorpH

15

8-1. Grounds for the new criteria (4)Not applicable for cases in which long-term effects of disinfection is unnecessary
13(sprinkling use, recreational use)

Not applicable for landscape use (handling not permitted, ecosystem preservation)

However,

Possible to control regrowth

new criteria
Free: 0.1mg/L or more
Combined: 0.4mg/L or more

Field survey…
(Drinking water criteria)
Free: 0.1mg/L or more
Combined: 0.4mg/L or more

Control of regrowth of pathogenic bacteria in distribution

Residual chlorine

8-1. Grounds for the new criteria (2)1. Corrosion and blockage of pipes and other equipment

facility malfunction

3. Outbreak of Chirnomid (imago/larva) (toilet flushing)

2. Growth of algae (Landscape use, Recreational use)

1. Red water, colorless, cloudAppeal and acceptance

4. Deterioration of the quality of reclaimed wastewater

3. Accidental intake

2. Cross-connection

1. Loss of residual chlorine in the distribution system

Hygienic safety

9-1. Consideration for treatedwastewater reuse

16

Turbidity of 2 or less as value to be observed at all times
to ensure effective treatment
14

Coagulation and sand filtration should be added

Control of protozoa (recreational use)

Turbidity of 2 or less as target value to ensure effective treatment

No blockage, sand filtration should be added

Against facility malfunction

Treatments / Turbidity

8-1. Grounds for the new criteria (3)- 275 -17

Example of posting of notices that reclaimed wastewater is usedand not for drink
191) Posting of notices to users that reclaimed wastewater is used

9-3. Accidental intake (1)Example of distinction by color-coding the pipes(Yellow is reclaimed wastewater, blue is drinking water)

1) Place signs on or color-code pipes and other equipment

9-2. Cross connection (1)ＰＰColoring

Reclaimed wastewater

18

20

Reclaimed wastewaterflow in tube

Example of sprinkling use that is hard to produce aerosol

Reclaimed wastewaterpercolate through thehole2) Prevent of accidental intake of aerosol (sprinkling use)

9-3. Accidental intake (2)Example of method for confirming cross connection

Drinking water

Shut thevalve

Cross connection

Inspect the cross connection
by the color of the water

2) Inspection for cross connection

9-2. Cross connection (2)- 276 -11. Future task

Changes in roles of seweragecreation of preferable water circulation
and water environment

utilization of sewerage resources

water quality control in public water bodyspread of flush toilet

prevention of inundation

public sanitation

23

5. Study on the possibility of application to new purposeof use4. Development of cheap and advanced wastewater
treatment

3. Improvement of analysis methods of pathogens

2. Study on the ingestion scenario

1. Study on the criteria for viruses

Growing interest in favorable
water environment- Water quality control of
public water bodies- Enhancement of publicsanitation- Sound urban development

Objective

10. Amendment of sewerage law (1)Amendment in October 2005

Suitable reuse of treated wastewater…

24

The new criteria and considerations were proposed by
the Committee on Reclaimed Wastewater Quality Criteria.
We express our deep appreciation to the members of thecommittee who extensive effort into developing andproposing the guidelines.

Acknowledgement

Recovery of good quality waterside spaces in urban areas-

NEW

Quality standards for final effluent
E.coli N.D./100mL
Turbidity of less than 2mg-kaolin equivalent/L- Culvert- Recreational use facilities

Shielding, fences etc. must be installed
to prevent entry to the facilities

Structural standards

10. Amendment of sewerage law (2)- 277 -Thank you very muchfor your attention !

ESTABLISHMENT OFGUIDELINES FOR THE REUSE OF
TREATED WASTEWATER

10th Japanese German Workshop on
Wastewater and Sludge Treatment, Berlin.

Semi-centralized water systems for rapidly
growing urban areas

Martin Wagner*, Peter Cornel**Technische Universitaet Darmstadt, Institut WAR, Petersenstr. 13, 64287
Darmstadt, Germany
Abstract: The rapid development of big cities worldwide leads to infrastructure
problems regarding water supply and sanitation systems. Conventional systems
cannot keep up with the rapid growth of the cities. In recent years there havebeen many discussions about alternative supply and sanitation systems, which
are to solve the discrepancy between city growth and the demand for supply andsanitation systems. Furthermore, these systems should deal in a sustainable way
with natural resources. Different kinds of sanitation systems are discussed, as
alternatives for conventional central sanitation systems, so-called “End of Pipe”
systems. The existing experience about conventional supply and sanitation
systems must be evaluated and new systems must be adapted to the local
boundary conditions of future cities. The paper presents a supply and sanitation
system (semi-centralized sanitation system) which might prove as a solution for
rapidly growing big and also mega cities.
Keywords: rapid city development, big cities, sanitation systems, semicentralized sanitation systems

Introduction
In the future, modern city planning should put a higher emphasis on the principleof sustainable development than it has done until today. Furthermore, city planning should deal conscientiously with the environment in order to get a higher
acceptance on the part of the cities' inhabitants. Infrastructure planning is one of
the most important sectors of city planning. Therefore, infrastructure planningshould follow the development of the cities (spatial spread) to guarantee efficient supply and disposal services. However, there are multifaceted problems
especially in rapidly growing cities, and infrastructure cannot fulfil its duties andresponsibilities. Thus, the supply of the city with drinking water, the treatmentof waste water and the disposal of waste cannot be ensured.
In this paper, after some facts about future city development are listed, sanitation
systems will be introduced in detail. Then so-called semi-centralized sanitation
systems and semi-centralized supply and treatment systems are described andcompared with conventional centralized and decentralized sanitation systems.
Finally, a conclusion rounds off the paper.

- 279 -

Semi-centralized water systems for rapidly growing urban areas

2

Future city development
There are several main reasons which might influence the development of big
cities worldwide. Three of them will be discussed below:x

The development of cities is different all over the world. In 1994, only
three of the world's 10 largest cities were located in developed countries. By 2015, this number is expected to decline further to two, onewill be Tokyo (Japan). However, whereas Tokyo’s population is estimated to increase by less than 5 percent during this period, cities likeJakarta (Indonesia), Karachi (India), Lagos (Nigeria), and Dhaka(Bangladesh) are expected to grow 60 to 75 % [Biswas et al., 2004]. In
2015, from the estimated 27 mega cities - cities exceeding a populationof ten million inhabitants - there will be 15 in Asia [cp. Dhakal, 2002].

x

There is a difference between the growth of big cities in the developed
and the developing world. For example, New York, Paris and London
are three mega cities in the developed world. These cities have growncontinuously throughout the 20th century. The growth tendency of mega
cities nowadays has changed. The development in a gradual process
over a long period, such as New York and London, allowed progressive
and effective development of the necessary infrastructure systems, e.g.
sanitation systems [cp. Biswas et al. 2004]. In contrast, the development of big or mega cities in developing countries is much faster.
Therefore, necessary infrastructure development cannot keep up withthe rapid growth of these cities.

x

Beside the rapid growth of big cities urbanization is increasing, too. In
2000, more than half of the world’s population lived in cities. During
the past 30 years, the urban population in developing countries has tripled. Urban areas in Africa, Asia and Latin America are growing withan average rate of one million people per week [Perlman et al., 1998].
Africa has the fastest rate of urban growth in the world. It is expectedthat by 2025 the continent’s urban population will have grown from
300 million to 700 million or from 30 % to 52 % of the total population[Cross and Morel, 2004]. Developing countries will absorb nearly all of
the world’s population increase between today and 2030. The estimatedurban growth rate of 1.8 % per year for the period between 2000 and
2030 will double the number of city dwellers. Meanwhile, rural populations are growing hardly at all. Likewise by 2030 more than half of all
Asians and Africans will live in urban areas. In Latin America and the
Caribbean, at the same time, 84 % of the inhabitants will live in urban
areas, a level comparable to the United States [Abhat et al., 2005]. Urbanization in developing countries is increasing, even with declining
industrialization and infrastructure and despite fewer jobs and decreasing salaries. Infrastructure development cannot keep up with the risingnumber of city dwellers. Therefore, the new big cities in the developingworld have particular problems with insufficient infrastructure systems.

- 280 -

Semi-centralized water systems for rapidly growing urban areas

One result of the rapid growth of big cities is lack of water. The local water demand of big cities is much higher than the availability of usable natural water
resources, a fact almost independent from the regions' climatic conditions. The
high population density of big cities leads to a great demand for water in a comparatively small area and thus to the exploitation of water resources. Furthermore, because of the rapid city development the lack of sanitation systems andwaste water treatment plants leads to additional pollution of the available water
resources. Thus, the usable water resources will be reduced twice: (1) by theenormous water demand due to the high population density, (2) by polluting thenatural water resources via discharging untreated waste water into the water bodies.
Evaluating the above mentioned facts one may state, that in the future, the improvement of infrastructure systems, especially in rapid growing big cities in thedeveloping countries, is one of the greatest challenges for countries throughout
the world. For the development of future cities sustainable and adapted solutions
are needed taking into account local boundary conditions. Therefore, future city
planning and in particular infrastructure planning in rapidly growing cities are achallenge for all sanitary engineers, sociologists, architects, traffic and transportation engineers etc.

Sanitation systems
The development of future cities and thus the infrastructure is highly dependent
on the efficiency of the sanitation system.
Sanitation systems can be classified into three categories. In Tab. 1 three different categories of sanitation systems are listed, which will be discussed below.
Figure 1: Categories of sanitation systems
Category
I

II

III

Description
conventional “End of Pipe” systems with a combined sewage system or a separate sewage system
and a wastewater treatment plant (WWTP)
separate collection of yellow water (urine) andblack water (all other water). This system realizes
a closed nitrogen and possibly phosphorus cycle
without water reuse
separate collection of yellow water, grey water(from showers) and brown water (from toilet).
This system realizes a closed water and nutrient
cycle with water reuse

With conventional “End of Pipe” sanitation systems (category I) waste water iscollected in conventional sewage systems (combined and separate sewers) andtreated in a wastewater treatment plant (WWTP) – quite often located at thecity's borders. In advanced treatment plants the nutrients nitrogen and phospho-- 281 -

3

4

Semi-centralized water systems for rapidly growing urban areas

rus are removed in order to avoid eutrophication of the receiving water bodies.
The treated waste water is discharged into water bodies (river, sea, groundwateretc.). Most of these “End of Pipe” sanitation systems are so-called centralized
systems. In industrialized western nations these conventional centralized system
are very common.
In sanitation systems of category II, waste water from different water flows, e.g.
yellow water, brown water, grey water, is collected separately. Yellow waterconsists of human urine and has the highest percentage of nitrogen compoundsof all wastewater flows. Separately collected yellow water can be used - after acertain storage time - as fertilizer in agriculture. Brown water and grey water are
not collected separately. They are pumped into a WWTP and discharged after
treatment. In this kind of sanitation system water reuse is not realized but thenutrient nitrogen in the yellow water is reused in agriculture.
In sanitation systems of category III, sanitation is similar to category II regarding the collection and treatment of waste water; the water flows are collected
separately. Water reuse in this system is realized by reusing the grey water for
toilet flushing, garden irrigation etc. Grey water, which originates from showers,
wash basins and washing machines, is only slightly polluted waste water, with
COD levels < 400 mg/L, low in ammonia, phosphorus and faecal coliform bacteria. No complex treatment process is needed to clean this water. After treatment it can be used as service water in private households or in public buildings,
e.g. for toilet flushing, which is approx. 30 % of the total water demand in private households. As a result, the city's demand for drinking water is reduced
significantly, thus solving part of the problems of insufficient water supply. Furthermore, due to water and nitrogen recycling, the cycle of water and nitrogen ispartly closed. All described systems can be realized as centralized as well as
decentralized systems.
Sanitation systems of category I (see Tab. 1) are normally realized as centralized
systems. In centralized systems waste water from all parts of the city is collected, transported in a sewage system, treated in a central treatment plant and isthen discharged into the receiving water bodies. Beside domestic waste water thecollected waste water also contains industrial waste water. Because of the potential existence of hazardous substances in industrial waste water, the reuse of thiswater might turn out difficult. A centralized system is designed and dimensioned
for a defined period of time. Therefore, the necessary capacity of the sewage
systems and treatment plants must be estimated and calculated prior to the planning stage.
Sanitation systems of category II and III (see Tab. 1) can be implemented depending on local conditions. In totally decentralized systems, i.e. within small
living communities (about 10 to 1000 inhabitants), the waste water is collected,
transported, treated, discharged or reused in each individual house or a relatively
small house cluster, respectively. The length of transport units (pipes, sewers) isvery short; treatment units are located near the houses, and in the majority ofcases the user himself operates the treatment units.

- 282 -

Semi-centralized water systems for rapidly growing urban areas

Sanitation systems to be implemented in future cities, must be dependable, economical, and sustainable. Therefore, a flexible sanitation system with a closed
cycle for water and nutrients (category III in Tab. 1) will be the preferred system, fulfilling the requirements of future sanitation systems in big cities. Besidecentralized and decentralized sanitation systems there is a third system to bementioned. In the next chapter this system – the semi-centralized sanitation system – is described as a sustainable sanitation system for rapidly growing big
cities.

Semi-centralized sanitation systems as a solution for
future cities
Conventional centralized sanitation systems are developed using modern process
technology, are designed to work reliably and to reach a high treatment efficiency, while fulfilling the economic demands at the same time. In order totransport drinking water and waste water, pipes and sewers of great lengths andlarge diameters are needed. The mixture of industrial and domestic waste waterand the long distances between consumers and treatment plants prevent an economic water reuse [Cornel et al., 2004]. Centralized systems are not flexible
enough when considering the rapid growth of the cities in the future; size adaptation is very difficult. These cities need a very high capital investment and haveto consider the estimated development prior to starting the implementation of thesanitation systems. Especially construction and enlargement measures cannot
keep up with the rapid growth of the new big cities, thus resulting in higher costs
compared to big cities nowadays.
The major drawback of decentralized systems is that it is difficult to guarantee
constant professional operation and maintenance. The treated water for reuse
purposes needs a good quality standard, and the health protection of the consumers must be ensured. These conditions cannot be guaranteed by the operators
in a decentralized system (house owners). Furthermore, low-level technology
will mostly be used in decentralized systems, thus achieving low maintenancecosts and thereby low-cost systems. This may result in insufficient effluent quality.
Semi-centralized supply and sanitation systems encompass the scale of application, responsibility, operation, treatment processes, and scope of reuse. Semicentralized systems combine both the advantages of centralized and decentralized systems with the avoidance of their disadvantages. Compared to conventional centralized systems, in semi-centralized systems short pipe and seweragesystems are realized, hence the recirculation of water for reuse might be economically interesting. A separation of industrial and municipal waste water ispossible, thus relieving the wastewater treatment plant as well. In relatively
small areas the implementation of dual piping (for supply and reuse) is feasible,
thus allowing water reuse. By using modularization, semi-centralized systems
offer a higher flexibility and a better potential for enlargement and adaptation.
Due to the larger scale of semi-centralized systems compared to decentralized
systems, professional operation and supervision of the treatment systems are- 283 -

5

6

Semi-centralized water systems for rapidly growing urban areas

guaranteed. Accordingly, semi-centralized systems can keep up with the quality
standards of water reuse and consumer health protection.
For future cities the semi-centralized sanitation system concept based on category III of sanitation systems (see Tab. 1) is a progressive and economic system
which will offer improved water reuse in urban areas compared to today’s centralized systems. With these “Semi-centralized Supply and Treatment Systems”(SESATS, see Weber et al, 2005) an efficient integrated city planning can berealized, including the necessary infrastructure measures. The relatively small
service areas for SESATS allow short transport distances between the treatment
units compared to centralized systems. The treatment units are situated close toeach other. Therefore, the effort for integrating planning, construction and connection of different parts of infrastructure (water supply, wastewater treatment,
solid waste disposal) can be reduced, compared to large centralized systems.
When applying SESATS, well organized operating teams and systems are required to guarantee the successful and safe water reuse within the city regions.
In Fig. 1 centralized and semi-centralized supply and treatment systems arecompared. Centralized systems supply the whole city with tap water and also
treat all of its waste water and waste. Semi-centralized systems supply single
districts within a city with water and treat waste water and waste from single
districts.
emissionenergypotablewater
products

City

wastewater

districts

solid waste

Figure 1: Comparison of centralized and semi-centralized supply and sanitation systems [Weber et al., 2005]
The SESATS - as described above - combine treatment facilities for water,
waste water and (organic) waste. These plants also supply service water forhousehold use and intra-urban irrigation for one district within the city (see Fig.
2). Furthermore, because of the combined treatment of organic waste and sewage sludge from wastewater treatment, the production of electrical energy andheat is feasible, which then can be used at the treatment plants themselves or in
the neighbourhood.

- 284 -

energypotable water

service waterSemi-centralized water systems for rapidly growing urban areas

residual
w atertreatm ent

raw w ater

w aste w ater
residual

Supply and Treatm ent Unit
waste water

w astew ater
treatm ent

w astetreatm ent

w astew asteFigure 2: Scheme of one unit of a semi-centralized supply and sanitation
system [Weber et al., 2005]

Conclusion
The infrastructure of water supply and sanitation systems is deficient in the majority of the rapidly growing cities in developing and emerging nations. The welldeveloped big cities do not only have problems with insufficient infrastructure,
but also with the necessary extension measures and regular maintenance of thecurrent infrastructure. Thus, it is important to evaluate, how the infrastructuredevelopment can keep up with the city's rapid growth. The sustainability of cityand infrastructure development should be considered in the progress. Semicentralized supply and sanitation systems, which are based on nutrient recycling
and water reuse in relatively small units, may be a suitable ecological, economical and sustainable solution for the big cities. It is not possible to determine astandard size for semi-centralized systems. It is rather necessary to evaluate thesize for each big city under investigation, thereby taking into account the local
boundary conditions (e.g. population, size of city area) and individual needs.
Furthermore it has to be considered that the spatial, administrative and juridical
frameworks of a developing area take serious influence on the optimal size. The
calculated size from 50,000 up to 100,000 inhabitants of the ’ideal developmentsize‘ is based on several model-assumptions which have to be depleted by theactual figures of the actual development area. The specific local and regionalparameters determine the recommendable size of the supply- and disposal-areaon the one and the choice of the best-possible adopted treatment methods udn
techniques on the other hand. Generally it can be acted in consumption that thecalculated developing-size from 50,000 up to 100,000 inhabitants is reliable interms of a guide value or benchmark.

- 285 -

7

8

Semi-centralized water systems for rapidly growing urban areas

Acknowledgement
The authors want to thank the German Ministry of Education and Research forthe founding of the research project “Semi-centralized supply and treatment systems for urban areas in China”. This project was the fundament of the present
paper.

References
Abhat, D. Dineen, S.; Jones, T,; Motavalli, J. ; Sanborn, R. ; Slomkowski, K. (2005):
Cities of the Future – Today’s “Mega-cities” are Overcrowded and Environmentally
Stressed, Environmental Magazine, Volume XVI, Number 5, September/October
2005
Bismas, A. K.; Tortajada, C. (2004): The water challenges of Megacities, Third World
Centre for Water Management; Professor Jan Lundqvist, SIWI; and Dr. Olli Varis,
Helsinki University of Technology
Cornel (2003); “Semicentralized supply and treatment systems for urban areas in China”
Research project, financed by the German Ministry of Education and Research, project number: 02WD0607
Cornel and Wagner (2002): Decentralized Sanitation Concepts for Urban Areas, presentation at EET Paris, 17th Nov. 2002
Cornel, P.; Wagner, M.; Weber, B. (2004): Semi-centralized Sanitation Concepts for
Urban Areas in China, not published, Institut WAR, TU Darmstadt, 2004
Cross, P.; Morel, A (2004): Pro-poor strategies for urban water supply and sanitation
services delivery in Africa, Water and Sanitation Program Africa, Abstract Volume,the 14th Stockholm Water Symposium August 16th – 20th 2004
Dhakal, S. (2002): Mega--Cities in Asia: An (Un) Sustainable Development?, international science roundtable for the media – 4th June 2002, Bali, Indonesia
Perlman, J.; Hopking, E.; Jonsson, Å (1998): Urban solutions at the poverty/Environment
intersection, the Mega-Cities Project, Publication MCP – 018, 1998
Weber, B., Cornel, P., Wagner, M. (2005): Semi-centralized Supply and Treatment Systems for (fast growing) Urban Areas, IWA Conference Wastewater Reclamation andReuse for Sustainability (WRRS2005)”, Jeju, Korea Nov. 7 - 11, 2005

- 286 -

- 287 -Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Introduction

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

guarantee efficient supply and disposal services• infrastructure planning should follow the development of
the cities:• dealing conscientiously with the environment:
better acceptance of the inhabitants• in future: modern city planning should put a higher
emphasis on the principle of sustainable development

InstituteProf. Dr. Martin Wagner

Semi-Centralized Water Systems
for Rapidly Growing Urban Areas

Institute

3

1

Content

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China• development of cities worldwide– more large cities in developing countries– by 2015, 60 % to 75 % expansion of the populationin large cities in developing countries– by 2015, 15 of 27 of the largest cities – with apopulation of more than ten millions – in developing
countries• difference of city development in developed anddeveloping countries– developing countries: very fast growthin only some decades– developed countries: slow growththrough the whole 20th century

Future city developments

Institute• Conclusions• Semi-centralized sanitation systems as a solution
for future cities• Future city development• Introduction

Institute42

- 288 -Semi-centralized supply anddisposal systems for fast
growing urban areas in China[Taubmann n.d.]

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

semi-centralized sanitation systems

flexible system with a closed cycle for water and nutrients• requirements of sanitation systems in future cities:– dependable– economical– sustainable– flexible• preferred systems:• problems of cities:– insufficient infrastructure systems– lack of water resources– additional pollution of available water resources

Future city developments

Instituterural population

urban population

e.g. growth-rates of urban populationin P. R. China (1962 up to 2001)

Institute

7

5

137

City

437

solid waste

wastewater

emission

urban districts

semi-centralized system

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

3 3

8

6

OceaniaSouth-East-Asia

Asia

208 East115

South-Asia

234

West-Asia

23 38

303

749

a number of semi-centralized supply and treatment units
instead of one big unit

products

potablewater

energy50

Eurasia20

Sub-Saharian
Africa288

North-Africa

15 40

centralized system

Institute

Latin America
and Caribbean

60

15 20

developed countries

without sanitation

without clean drinking water

938

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

So many people live in these regions (in million)

Water deficiency

Institute

- 289 Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

shorter and smaller pipe and sewerage systems

water (and nutrient) recirculation for reuse

separation of industrial and municipal waste
water

modularization of treatment units

better potential of enlargement and adaptation

•

•

•

•

•

advantages:
semi-centralized vs. centralized sanitation
systems

Institute

Institute

11

9Institute

Institute

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

1210

w aste w ater

raw w ater

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

w atertreatm ent

w astew ater
treatm ent
w astetreatm ent

Supply and Treatm ent Unit

service water(supply and treatment)

potable water

w astew asteresidual

w aste w ater

residual• one unit of a semi-centralized sanitation system

Institute

Instituteenergy- 290 15

13

treatment stepenergysludgewaste

process waste waterend productprocess water

waterworks sewage

black water

grey water

material flows

drinking water purification

Legendewaterworks
sewagedrinking water
purification
treatment

raw water(surface water)

Institute

Institute

black water

grey water

process
wastewater

waste

energyreceiving stream/use

sludgeresiduelactic acid14

16

integrated system

black water
treatment

grey water
treatment

waste
handling

process waterSemi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

- 291 -treatment stepenergysludgewaste

process waste waterend productprocess water

waterworks sewage

black water

grey water

material flows

drinking water purificationwaterworks
sewagedrinking water
purification
treatment

raw water(surface water)

Legendegrey water

black water

grey water

black water

material flows

Institutetreatment stepenergysludgewaste

process waste waterend productprocess water

waterworks sewage

black water

grey water

drinking water purification

Legendewaterworks
sewagedrinking water
purification

raw water(surface water)

Institute

black water
treatment

grey water
treatment

waste
handling

process
wastewater

waste

black water
treatment

grey water
treatment

waste
handling

process waterSemi-centralized supply anddisposal systems for fast
growing urban areas in China

process
wastewater

waste

process waterSemi-centralized supply anddisposal systems for fast
growing urban areas in China

energyenergy19

receiving stream/use

sludgeresiduelactic acid17

receiving stream/use

sludgeresiduelactic acidSemi-centralized supply anddisposal systems for fast
growing urban areas in China

•

•

•

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

black water:
waste waster from toilettes flushing and kitchengrey water:
waste water from showers and bathtubs, hand basins andwashing machines

sludge: combined treatment with residual waste

treated black water: discharge or reuse in urban zones

treated grey water:
service water for using in private household orafter treatment:••

waste water treatment

Institute• because of the reuse of water there is a saving of tap
water• available rain water by rainwater harvesting satisfies
only a third of the needed amount for toilet flushing,but is useable for irrigation and street cleaning• use of ground water is often forbidden especially inurban areas, because of scarce volume problems:
underground subsidence, salt water intrusion

Water supply

Institute

20

18

storage withcold /warm precipitation
aggregate /flocculation

biofilter

influent„Grey water
concentrates“

precipitants/flocculants
storage

Institute

screenings

fine screen

storageblowerSBR

MBR II

sludgeUV-Disinfection

sludgesludgeeffluent

effluent

effluent

effluent

effluent

UV-Disinfection

blowersludgeceramic
membrane

blowerMBR I

biologicalsand filter

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Backwash water- 292 -

21

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

mixing station grey water• SBR Thailand Water house

Institute

Institute24

22

- 293 -Institutematerial flows

black water

grey water

black water
treatment

grey water
treatment

waste
handling

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

process
wastewater

waste

process waterSemi-centralized supply anddisposal systems for fast
growing urban areas in China

outputreactorbiogas exhaust

input
preparation
27

25

receiving stream/use

sludgeresiduelactic acidenergyPilot Plant for lactic acid fermentation

treatment stepenergysludgewaste

process waste waterend productprocess water

waterworks sewage

black water

grey water

drinking water purification

Legendewaterworks
sewagedrinking water
purification
treatment

raw water(surface water)

Institute
Semi-centralized supply anddisposal systems for fast
growing urban areas in China

treatment stepenergysludgewaste

process waste waterend productprocess water

waterworks sewage

black water

grey water

material flows

drinking water purification

Legendewaterworks
sewagedrinking water
purification
treatment

raw water(surface water)

Institute

black water

grey water

process
wastewater

waste

energyreceiving stream/use

sludgeresiduelactic acid26

28

integrated system

black water
treatment

grey water
treatment

waste
handling

process waterSemi-centralized supply anddisposal systems for fast
growing urban areas in China

challenges: process control for mono substrates is wellknown and state of the art technology
in Contrast, organic waste is very inhomogeneous andinconstant in it‘s composition

solution: optimization of process control for the generation ofother products, e.g. lactic acid. The technology is acombination of classical anaerobic waste treatment and silage
production processes

problem: main product of anaerobic waste treatment (thermalenergy from the biogas) has no preferable user under the given
spatial situation (mono functional habitation)

waste treatment

Institute

- 294 -Institutemoderate density
housing areas(housing with up to 4
storeys proper)- 6% -

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Example:City
Qingdao
Example:City
ofof
Qingdao

access road
(1st and 2nd order)

31

29

low desity
housing areas(single-family and twofamily houses with up to
2 storeys proper)- 8% -

high density
housing areas(housing with up to 6
storeys proper)- 42% -

13,000residents
residents
13.000

general public demandarea(social infrastructure aswell as supply anddisposal center)- 8% -

total area
500.000 m²

Model Cell

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

green space-16% -

total area 500,000 m²

Institute

1

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

2

4b

4a

Institute

5 (b)Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Location of supply and disposal centre

Model-cell with 13,000 residents

3b

3amodeling recommendable dimensionsof space and residents

Institute32

30

- 295 -Key Questions

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China• what are the challenges in integrated planning and approval
processes (for organisational reasons)?

• are there other strategies to reach sustainability (in cases ofsupply and disposal systems)?

• is the idea feasible to make development in fast growing
urban areas (more) sustainable?

Institute

Institute

35

33

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Semi-centralized supply anddisposal systems for fast
growing urban areas in China

presented paper

This project was the fundament of thetreatment systems for urban areas in China”.

research project “Semi-centralized supply andFederal Republic of Germany for the founding of theThanks to the Ministry of Education and Research of the

Acknowledgement

Institute• developing integrated planning and approval processes for
integrated semi-centralized supply and disposal systems• optimising technical concepts

actual research• integrated supply and disposal systems of a size between
50,000 and 100,000 residents should be preferred

Current research status

Institute36

34

- 296 -Semi-centralized supply anddisposal systems for fast
growing urban areas in China

Thank you for your attention
37

Thank you for your attention

InstituteSemi-decentralized infrastructure in the development areaof Knittlingen, Germany
Marius Mohr and Walter Trösch Fraunhofer-Institute for Interfacial Engineeringand Biotechnology Stuttgart, Germany
Introduction
The waste water treatment in Germany has today reached a really high standard.
Referring to German statistics in the year 2001 94.6 % of all the inhabitants had access tothe public sewer system. 98 % of the waste water was cleaned up to the recommendationsof the EU rules. If it is additionally assumed that Germany is rich in ground water
resources and situated in a region with sufficient rainfall, why to look for new solutions
for urban infrastructure and water management.
But there are several reasons for a revision towards sustainability:
The reconstruction of 485 000 km of public sewers which have been invested in thelast 100–120 years is very expensive and will become even more expensive theolder the canal system gets.
In the different water bodies an increase of organic micro pollutants (hormones like
substances, pharmaceuticals) have been recorded which can not be degraded instandard waste water treatment plants. Additionally there is no hygienic barrier
between treatment plants and the receiving water bodies, causing the distribution ofpolyantibiotic resistancies in the microbial world.
By climatic change along with the global temperature increase it has been analyzed
that rain events tend to be shorter and heavier without changing the yearly quantity
resulting in increased hydraulic problems and floodings. In addition with aprolongation of the climatic trend drinking water resources may also be shortened inGermany.
The demographic change especially in the new federal states of Germany shows
the inflexibility of the existing infrastructure and state of the art technique forwaste water treatment: By reduction of inhabitants in several regions the specificcosts for the water treatment have increased to non acceptable levels.
The increasing global demand for energy which is covered mainly by fossilmaterials results in increasing costs for energy, stimulating savings of energy andthe search for new resources.

- 297 -

This challenge is mirrored by a new innovative water management concept ofFraunhofer-IGB in the frame of the Project DEUS 21, which is funded by the Ministry of
Education and Research (BMBF) as a technical demonstration.
Whereas standard water management is mainly operated in centralized big installations
DEUS 21 tends to semi decentralized systems. In a first order of magnitude systems of
100 to 10,000 inhabitants are in the focus of basic designs. Main principal of the design iscircuit processing. Thus biogas is the recycling product in respect to the carbon bone oforganic pollutants. Additional value recycling substances are Ammonia and Phosphorous
to be used as artificial fertilizer. Rain water collection and reuse as new resource of a
specific quality of drinking water is incorporated to the concept. The demonstration plantis set in operation in the small town Knittlingen near Pforzheim, Germany, in a newresidential zone for about 100 individual houses.

Rainwater from the roofs of the buildings and the residential streets is collected
separately and stored in underground stainless steel containers. This water is cleaned up
according the requirements of the drinking water rule of the European Union andachieves drinking water quality. As so called „care“ water it is redistributed to thehouseholds in a separate net.
Waste water is collected by a vacuum sewer system. In a central station the vacuum is- 298 -

generated. The waste water of the buildings is collected in a buffer store and sucked away
by opening an air valve at the end of the pipe grid. As option the vacuum sewer system canbe installed inside the building to make use of water saving toilets and kitchen waste
mixers.
The semi decentralized waste water cleaning unit is situated in the centre of theresidential zone to minimize the sewer grid. By using an anaerobic low temperatureprocess water depollution is realized along with biogas production. Biogas is used in acogeneration unit to produce electricity and heat. The value substances Ammonia andPhosphorous are recycled in form of crystalline artificial fertilizer, which easily
compete economically to synthetic fertilizers. The outflow of the treatment plant is freeof solids especially pathogens in regard of the micro filtration integrated to thebioprocess. The effluent shows bathing water quality (EU-recommendations) and canbe reused as irrigation water without poisoning soil and ground water.
Water house
The water house is the operation centre for all techniques of the DEUS 21 water
management concept. It is also information and presentation centre for the population andexternal national and international visitors. The building itself is a cube partially with
underground floor. The big window front allows insight to the process and the operation
units.

Water house Knittlingen

The water house contains the following process steps and containers:- 299 -

3.
•
The upgrading and redistribution techniques for rainwater and a 10 m big
container for "care" water ready to use.
•
The vacuum station, which causes the depression in the canal system anddoes by means of this extract the waste water by suction.
•
The waste water treatment plant as pilot unit for 50 – 70 inhabitants andlater on for all inhabitants of the residential zone
As the water house is situated in direct neighbourhood to residential buildings with theadvantage of short distances for the sewer, care water and drinking water nets the zero
emission standard must be very high: Especially noise emission has to be decreased andindividual noise reduction techniques have been installed for individual noise sources.

Rain water use
Rainwater is not only available in a certain quantity covering about 50 % of the drinking
water demand but also represents water in a special quality. Rain is a product of solar
irradited evaporation of surface water which is recondensed by natural climatic conditions.
Source collected rain water has compared to drinking water reduced salinity andtherefore is qualified to be used in all cases where water is heated to reduce calzification:dish washer, washing machine, water heater inside buildings for showers etc.
In addition rainwater collection and storage if used area wide reduces the danger offlooding.

In Knittlingen rain water of roofs and residential streets is collected. In a first filtration
step (0.6 mm) rain water is cleaned from coarse solids. Included in the first separation
apparatus is a possibility to get rid of the higher polluted first liquid flush. The precleaned
water is then stored in tanks of 300 m total volume. It is soften oxiginated duringstorage to prevent fouling.
3- 300 -

Cisterns for rainwater storage

To create care water in quality (hygienically) of drinking water the rain has to pass aceramic ultra filtration (60 nm) membrane with an extremely sharp cut off to make sure to3

retain all the bacteria and viruses. The cleaned care water is stored in a 10 m container tocover demand peaks.
In a circuit distribution tube the soft care water is transported to the households incomparable pressure as the drinking water net is operated. The circuit is hold at constantcircuit flow to pass cyclic a UV-desinfection unit to prevent back contamination by
microorganisms.
Vacuum sewer system
As an advantage over conventional flushing sewer systems the vacuum sewer uses tubes
with reduced diameter so that investment and operating costs can be saved at infrastructure
realisation. In addition the system is flexible to demographic changes (ups and downs). The
user has in principle two options to get use of the system. The first option is conventional
dewatering of buildings. Waste water is collected in a special underground reservoir whichacts as fitting system to the vacuum sewer. Second option is the integration of the vacuum
tube inside the building to get use of vacuum toilets and kitchen waste mixer.

- 301 -

Vacuum station installed in the water house

The vacuum itself is generated inside the water house in a vacuum tank by two
redundant vacuum pumps. The tank is the reservoir and equilibration volume for thewaste water.

Waste water treatment
Waste water from the vacuum station is pumped into the anaerobic psychrophilic waste
water treatment reactor where the waste water is digested by anaerobic bacteria at inflow
temperatures. The reactor is equipped with a ceramic micro filtration unit in form of arotating disc filter. The filtration is operated in dead end mode to increase bacteria
concentrations together with incoming solids inside the bioreactor.

- 302 -

Rotation disc filter and reactor for waste water treatment

The special operating mode as dynamic filtration unit allows "in operation" cleaning fromfouling layers at disc surfaces by centrifugal forces. Thus high constant flux rates are
obtained. The anaerobic organisms digesting at first organic substances to methane and CO(biogas), which are used in a cogeneration unit to cover the energy demand of the cleaning
process, liberate nitrogen components during digestion of organics as NH and soluble
Phosphorous, too. By the addition of Magnesium salt to the filtrate of the membranebioreactor MAP is precipitated and can simply be recovered. The quality of the concentrate
is so good that the fertilizer is ready for use in agriculture.

2

+

4

Residual NH is adsorbed to an ion exchange material to concentrate the value substance.
From the regenerate is will be possible to strip Ammonia in an economic form to recover asecond artificial fertilizer: Ammoniumsulfate for example.
3

Conclusion
The demonstration waste water treatment plant in Knittlingen shows that it is possible torecover value substances from the water stream along with water regeneration ready forsecondary use: infiltration, irrigation, service water. The recycled products are biogas from- 303 -

C-bone of pollutants and fertilizer components. In regard of exporting the system todeveloping countries or arid zones the water treatment can be stopped after biogas recovery
if the water is sustainably used to irrigate and fertilize agricultural zones.

- 304 -

- 305 -Archivierungsangabe

Drinking water

Archivierungsangabe

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Fraunhofer

Wastewater

Rainwater

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

GroundwaterSpecific treatment and reuseRiver

Rainwater storage reduce the danger of flooding

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Fraunhofer-Institute forInterfacial Engineering and Biotechnology,
Stuttgart, Germany

Prof. Dr. Walter Trösch

10th Japanese German Workshop on Water Technology,
Berlin, 09.-10.10.2006

Drinking Water
Processing

Semi-Decentral urban Water- and Waste Water Management

Semi-DEcentralized Urban Infrastructure System DEUS 21

Archivierungsangabe

Archivierungsangabe

Drinking water

Centralwastewater
treatment
plant

River

Fraunhofer

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Irrigation

Rain water
storageRain Collection

Gär-RestDigestion
Rest
DisposalDecentralized
Sewage treatment unit

Energy/P-N Fertilizer

Kitchenwaste

Sewage Sewer
Vacuumsewer

Water

Application in house

Drinking water net

Rain water treatment

Rainwater net

DEUS 21

Knittlingen „ Am Römerweg“Semi-DEcentralized Urban Infrastructure System DEUS 21

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Sewer system

Fraunhofer

Wastewater

Rainwater

Drinking water
processing plant

Salt/heavy metals
Endocrine activities
Recombinant bacteria ( Multiresistance byhorizontal gene tranfer)
Pharmaceuticals

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 306 -IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Al2O3

Archivierungsangabe• Excellent Cut-off

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB• Membrane surface: 352-1450 cm2

4,5 mm• Discdiameter ∅: 152-312 mm• pore diameter: 0,2- 0,02 µm• Thickness:

2,5 (0,3)

5,0

Drinking waterrule (EU)Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Cross-section of a single discUltrafiltration disc for rainwater cleaning• Material:

Archivierungsangabe

0,06

Conductivity :(mS/cm)0,01

9,5

Rainwater

COD (mg O2/l):

Desalinatedwater

Quality of rainwater in Stuttgart: 10.10.2002(unfiltrated, private rainwater collecting unit, Trösch)Semi-DEcentralized Urban Infrastructure System DEUS 21

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Archivierungsangabe

Fraunhofer

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Filtration discSurface layer

Fouling prevention by centrifugal forces / in operation cleaning

Archivierungsangabe

Zur Anzeige wird der QuickTime™
Dekompressor „TIFF (LZW)“
benötigt.

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 307 -Archivierungsangabe

Archivierungsangabe

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Fraunhofer

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Irrigation

Rain water
storageRain Collection

Gär-RestDigestion
Rest
DisposalDecentralized
Sewage treatment unit

Energy/P-N Fertilizer

Kitchenwaste

Sewage Sewer
Vacuumsewer

Water

Application in house

Drinking water net

Rain water treatment

Rainwater net

DEUS 21

Knittlingen „ Am Römerweg“Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Pilot-scale ultrafiltration unit with rotating disks

Semi-DEcentralized Urban Infrastructure System DEUS 21

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Archivierungsangabe

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Scheme of a vacuum sewer system

Urban watermanagement DEUS 21

Archivierungsangabe

Dynamic ultrafiltration units (2 x 7,4 m2)
and pressure station for care-water
distribution

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 308 -IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Archivierungsangabe

4anaerobic

aerobic

1g/l COD = 0,4 l Biogas (70%CH4)

CO2, NO3, SO4, PO4

CH4 + NH3 + H2S +
H3PO4

-NH4

O2

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Consequence: Anaerobic psychrophilic waste water treatment

-PO

C

-OH

Biologically catalysed reactions within biodegradation gaseous products escape to the atmosphere

Archivierungsangabe

Reduced investment costs
for the sewer

Reduced digging costs

Development area Knittlinen: Vacuum sewers DN 60

Semi-DEcentralized Urban Infrastructure System DEUS 21

Archivierungsangabe

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

9lFraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Total organic load : 3.6 g/l d

Load stage 1 : 8.33 g/l d
stage 2 : 2.60 g/l d6l

Biomass concentration:
12 g/lOutput COD: < 100 mg/l

Anaerobic Waste Water treatment: Two stage cascade with intergrated
Microfiltration at 15-20°C

Input:
4,3 g COD/lArchivierungsangabe

Vacuum station

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 309 -IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Archivierungsangabe

4anaerobic

aerobic

CO2, NO3, SO4, PO4

CH4 + NH3 + H2S +
HPO3

-NH4

O2

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Aerobic biodegradation = Reduction of waste without economical benefit

-PO

C

-OH

Biologically catalysed reactions within biodegradation gaseous products escape to the atmosphere

Archivierungsangabe

Biogas lift loop bioreactor withsurplus sludge containment

Semi-DEcentralized Urban Infrastructure System DEUS 21

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Archivierungsangabe

Fraunhofer

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

without the addition of chemicals

Precipitation of Mg-ammonia-phosphate

Recycling and recovery of phosphor
components is possible:

MAP - Precipitations from digestion filtrate

Archivierungsangabe

Photo of the technical plant; in thefront and on right hand side therotation-disc-filter
and in the back the anaerobic gas
lift loop bioreactor

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 310 -Archivierungsangabe

Archivierungsangabe

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Air stripping at elevatedTemperature andprecipitation in an
appropriate acid

Ionexchange toconcentrate thedissolved Ammonia

Precipitation of Ammoniumsulfate to recover the remaining Ammonia
after MAP

Semi-DEcentralized Urban Infrastructure System DEUS 21

Archivierungsangabe

Archivierungsangabe

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGBHigh poduction numbers reduce investment costs !

Industrially preconstructed, each identical, remotecontrolled

Modular Water Infrastructure system including
rainwater catchment, water redistribution
and waste water purification
In modules:
for 1.000 Inhabitantsfor 10.000 Inhabitantsfor 50.000 Inhabitants??

Final conclusion:

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 311 -Archivierungsangabe

Archivierungsangabe

2

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

3

1

IndustryCity

Semi-decentralized
waste water treatment units designed for thereuse of cleaned waste water

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Optimized sewer gridfor collection and redistribution

area

Agricultural

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Rainwater collection
without problems ofinfiltration/exfiltration

Archivierungsangabe

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Liquid soil technique:Archivierungsangabe

Microfiltration 2

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 312 -Archivierungsangabe

Archivierungsangabe

Picture of thesettlement:

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Fraunhofer

IGB

Institut
Grenzflächen- undBioverfahrenstechnik• Blau: Bioreactors• Rot: Pumping station• Grau: Microfiltration

3D-graphic of the module

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Semi-DEcentralized Urban Infrastructure System DEUS 21

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

Semi-DEcentralized Urban Infrastructure System DEUS 21

Fraunhofer

Advantage:• No flushcleaning necessary• Reduced costs compared to vacuum sewers or free flow
systems• Construction of 7 pumping stations with 180 l pumping
volume per pumping act

Archivierungsangabe

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

Microfiltration of raw waste
water to separate solid andvolatile COD
Microfiltration of nitrification
effluents to produce a
Microorganisme free water
stream for infiltration or irrigation

Technical installation ofa high load aerobic waste
water treatment plant:

Archivierungsangabe

KA

Pressure sewers:(Variant 2)

Sewer development

Semi-DEcentralized Urban Infrastructure System DEUS 21

- 313 -Archivierungsangabe

Fraunhofer

Institut
Grenzflächen- undBioverfahrenstechnik

IGB

MBR in Heidelberg Neurott

Semi-DEcentralized Urban Infrastructure System DEUS 21

Archivierungsangabe

Fraunhofer

IGB

Institut
Grenzflächen- undBioverfahrenstechnik

0,4l /g COD

Semi-DEcentralized Urban Infrastructure System DEUS 21®

Basics of HydroSelf flushing system in rectangulartanks, round tanks and tunnel sewers Dipl.-Ing. Joerg
Steinhardt Dipl.-Ing. Bernhard Hommer September
2006

HydroSelf£
flushing system

Basics of wave flusher inrectangular tanks
round tanks andtunnel sewers

Dipl.-Ing. Jörg Steinhardt
Dipl.-Ing. Bernhard Hommer
September 2006

HydroSelf® flushing system in Singapore

HS_HydroSelf FlushingSystem 2006-09-29 GB- 315 -

jöhom.doc

®

Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

Basics of HydroSelf£ flushing system inrectangular tanks,round tanks andtunnel sewers
1. Introduction
The HydroSelf flushing system was developed by Steinhardt GmbH and put on themarket for the first time in 1985 as a novel flushing system with flushing gates. Whatwas special about the flushing gates was the hook closure, which could be locked
and unlocked exclusively via mechanical forces (water power) by means of anencased hydraulic cylinder. The electric control for larger tanks was included at alater point in time.
In Germany, in Europe and worldwide more than 1000 facilities, stormwater tanks,
reservoir channels and transport collectors have been equipped with the HydroSelf
flushing system.
The success of the HydroSelf
flushing system for tanks andchannels is based on the abrupt
opening of the flushing gate, whichcauses a flushing wave, similar to adam break. The flushing waterretained in the storage chambers by
the flushing gates flows out rapidly
and moves with enormous thrustforce over the soles of thestormwater tanks and channels to be
flushed. The result is so overwhelming, as dirt and even most stubborn deposits canbe removed and flushed away reliably with only one flush.
In order to be able to flush circular
tanks with the same positive result,the HydroSelf flushing system forround tanks was developed. The
radial flushing system operates witha mobile (flushing) container whichis connected to a central guide rod.
When the tank is filled in rainy
weather, the special closure
mechanism of the flushing container
is locked and retains the stored flush
water. After the rainfall, as soon as
the tank is empty again, the flushingprocess is initiated as the container suddenly moves upward. The flush water flows
out of the container bottom and flushes the sole of the round tank via one flushingprocess.

HS_HydroSelf FlushingSystem 2006-09-29 GB jöhom.doc - 316 -2 / 11®

Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

2. The principle of the HydroSelf flushing system
2.1 With flushing gates in tanks and sewer tunnels
The principle of the HydroSelf flushingsystem with flushing gates is simple butvery successful. The HydroSelf flushingsystem flushes stormwater tanks andchannels highly efficiently from a low
level with the energy of the stored water.
The storage chambers are located in thearea of the structure soles at the highpoints of the sole in “flushing streets” tobe flushed within a tank or at the
beginning of flush lanes in channels. The
flush water is retained by the flushing gates until the flushing process is either
initiated automatically or by hand via unlocking the closure mechanism.

Flush water is impounded in one orseveral storage chambers and retainedby the flushing gates. (The quantity offlushing gates must be selectedaccording to the type and dimensions of
the tank or channel.)

The sudden opening of a flushing gate
initiates the flushing process. (Several
flushing processes are initiated one
after the other, as soon as thedischarge is free again and the flushingsump empty.)

A powerful flushing wave (similar to adam break) is caused.

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Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

The turbulent shock wave generates
enormous shear stresses andguarantees the removal of deposits
from the tank and channel soles. The
large flush water volume ensures thatthe dirt is reliably transported to thedischarge.

2.2 With a flushing container in a circular tank
The HydroSelf flushing system forcircular tanks operates with a central
flushing container, which also
constitutes the storage chamber for theretention of the flush water. The outside
wall of the container corresponds to thestorage chamber walls in facilities withflushing gates. The system of container
flushing includes the integrated central
rod, which is positioned in the centre of
the tank together with the container andto which the guide rails plus damper
and the closure mechanism are
attached. Central rods which might
already exist and be necessary from thestatic point of view, e.g. of concrete inclosed stormwater tanks, can beincorporated. The surface of the tanksole in the circulating sealing area ofthe container edge must, however, be prepared in a special way and it must be
absolutely smooth and level.
Phase 1 – Dry weather
The dry weather inflow flows into thestormwater tank and then to thedischarge via the dry weather flume,
which is also used as flushing sump andis located at the outer edge.
Phase 2 - Rain
During rainfall, the tank is filled due to thethrottled discharge. This means that at
first the discharge area and then the
flushing sump will fill. If the water level
HS_HydroSelf FlushingSystem 2006-09-29 GB jöhom.doc - 318 -4 / 11®

Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

continues to rise, the closure mechanism of the flushing container will be locked. If it
keeps on raining, the tank will fill up. The flushing container will also fill, either
automatically via backwater gates or by means of an external filling installation.
Phase 3 – After the rain
After the rainfall, the tank will empty
again. The flush water will, however, beretained in the flushing container. The
stored buoyancy force generated by the
inclined container walls in the lower partcannot act at the beginning, as theclosure is still locked. Only when the discharge area of the tank and the flushingsump are empty, the mechanism is unlocked and the flushing process initiated.
Phase 4 - Flushing
The control unlocked the closure. The
buoyancy force can act now and lift thecontainer wall. The flush water flows outof the container and a radial, even,powerful flushing wave cleans the entire
tank sole in the direction of the outside
wall. The flush water with the removed dirt is collected in the dry weather flume andin the flushing sump and passed on to the sewage plant via the discharge area.
3. Advantages of the HydroSelf flushing system
Advantages 1
x Specifically extended flush wave with enormous thrust force
x Also suited for longer flushing lengths with larger water quantities
x Cleaning of flushing lengths exceeding 100 m by far
x Guaranteed removal of most stubborn deposits with one flush
Advantages 2
x Storage chambers are filled automaticallyx Cleaning also with partial impoundage
x Environmentally friendly and resource saving
Advantages 3
x Simple and sturdy technology
x Low maintenance due to the application of high-quality materials
x Flushing system tried and tested in more than 1000 facilities worldwide
Advantages 4
x Safety due to consultation and intensive support in the planning phasex Quick, competent and experienced service

4. Consulting the flushing system
Storm water tanks, reservoir channels and transport collectors are required, planned
and manufactured in most differing sizes, dimensions and shapes. The responsibility
for the planning usually lies with the consulting engineers. To ensure that suchbuildings can be approved, the stipulations made by cities, communities or operatingcompanies with respect to the operation must be considered and the respectively
applicable guidelines for the structural design must be complied with.
HS_HydroSelf FlushingSystem 2006-09-29 GB jöhom.doc - 319 -5 / 11®

Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

The system drawings in the Steinhardt GmbH technical documents will provide youwith an overview on the various possibilities of how to plan a HydroSelf flushingsystem.
Tank:

Tunnel sewer:

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Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

Round tank:

If you already have your design plans made, in many cases it is also possible toadapt the HydroSelf flushing system to the planned building. Experience has shown,however, that for the optimization of the HydroSelf flushing system, it is necessary toknow the hydraulic system of the tank or channel and its water management functionin the sewer system. The compilation below displays a selection of importantcharacteristics which should among others be included in the planning.
Tank

Large tank or small tank
Rectangular tank or circular tank
Stormwater overflow tank or stormwater retention tank
Function with the main closure or secondary closure variation
Power supply possible / not possible
Flush water supply granted

ChannelReservoir channel, transport collector
Round channel, rectangular channel, special profile
Function with the main closure or secondary closure variation
Power supply possible / not possible
Flush water supply granted

Further details with respect to construction and machine technology as well as
general hints can be found in the section “Important information for planners andoperators “ in the Technical documents relating to the HydroSelf flushing system.
Please do not hesitate to contact us for assistance in case of more complex planning
projects. Steinhardt GmbH will be happy to contribute its experience.
The most important element for flushing a tank or channel is flush water, which must
be collected and stored in the storage chambers.
HS_HydroSelf FlushingSystem 2006-09-29 GB jöhom.doc - 321 -7 / 11®

Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

The geometrical dimensions of the tank or the channels are necessary to establish
the flush water. To this end, the required widths of the flushing gates must be
determined. For circular tanks the size of the flushing container must be proportional
to the tank surface to be flushed.
Division (of the tank) in flushing lane
Determination of the quantity of flushing lane
Determination of the width of the flushing lane
Determination of the required flush water volume depends
Length of the flushing lane
Width of the flushing lane
Longitudinal inclination of the flushing lane
Settlements

Stand pipe DN 100

Picture of a typical storage
chamberwithstorage chamber length Lk
filling depth Tk (max. ca. 1.50 m)

Finished sole flushing lanestorage chamber width e.g.
as same as flushing lane width

The flushing sump at the end of aflushing street collects the flush water
quantity and the flushed deposits of one
flushing street. With larger facilities, thefollowing flushing process may only beinitiated if the discharge area and theflushing sump are empty again.
The content of the flushing sump [m³]should always be larger than the content
of the largest storage chamber and it
should at least feature such a dimensionthat the volume of the flush water plus
the deposits expected (e.g. ca. 30 % of
the flush water) fit in together.

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Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

Storage chambers

Flushing sump (content > 1.3 x flush water)

5. The control of the HydroSelf flushing system
For the automatic operation of the HydroSelf flushing system, two different control
systems are available.
Purely mechanically acting float controls can be used in smaller facilities and if noelectricity is available nearby. When planning such a facility, it is, however, absolutely
imperative that Steinhardt GmbH is consulted as early as possible, as the structuraldesign of the tanks and reservoir channels must especially be adapted to the control
system and coordinated with it.
If the model of a float control is not possible, then the electrically controlled HydroSelf
flushing system will be used. The electric control is standard for larger facilities. But it
is also applied in smaller stormwater tanks and for flushing channels. The operatingease and the increased flexibility also allow to comply with the customer’s special
wishes (telecontrol system). Each electric control is suited for automatic operationand manual operation alike.
5.1 Float control (no power requiered)
The mechanically controlled hydraulic system of the HydroSelf flushing system
mainly consists of the flushing gate/flushing container with a special hydrauliccylinder, a main float, a control float and the connecting hydraulic lines.
Each individual flushing gate requires its
own main float. A control float can beused for a maximum of two flushinggates. Example: For 4 pcs. flushinggates, 4 pcs. main floats and 2 pcs
control floats are required.

The arrangement of the main and control
floats is determined depending on therespective project. The main float serves
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Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

to lock and unlock the closure mechanism and must be capable of covering a lift
distance in a floating manner. Only after the top position has been reached, maywater flow into the storage chambers. The control float initiates the flushing process.
It must be located at a very low depth in the discharge area. For the initiation of theflushing process, the flushing sump must be empty.
Note: The flushing gate with the float-controlled HydroSelf flushing system is open in
the state of rest and it only locks in the event of rain when the rising water levelcauses the main float to float to the top.
5.2 The electric control
The electrically controlled hydraulic system of the HydroSelf flushing systemgenerally consists of the flushing gate/flushing container with a special hydrauliccylinder, the connecting hydraulic line, the hydraulic unit and the electric control (e.g.
in a safety cabinet).

All electric functional parts of the HydroSelf flushing system are located outside thestorm water tank. The hydraulic line leads from the hydraulic cylinders at the flushinggates or the container through the structure wall to the hydraulic unit (< 1.0 kW) in theexternal cabinet or control room. The hydraulic unit and the electric control can besupplied either wired ready-for-operation, mounted on a base plate or with aweatherproof safety cabinet for outdoor installation. Only the power supply and theelectrical connection must be carried out by the customer. It is also possible to realize
other installation options according to the customer’s request, e.g. in central control
rooms or the integration in larger cabinet installations.
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10 / 11®

Basics of HydroSelf flushing system in rectangular tanks, round tanks and tunnel sewers Dipl.-Ing. Joerg Steinhardt Dipl.-Ing.
Bernhard Hommer September 2006

A hydraulic unit can also be used to control more than one flushing gate in larger
tanks by installing a larger number of valves.
For the automatic, water level-dependant control, a float switch is required. The
positions of the probes are established for each project individually, mainly, however,
above the discharge area. The flushing process is initiated, if the dischargearea/flushing sump is empty and the flush water can run off freely.
Note: The flushing gates are always closed (locked) in the state of rest with theelectrically controlled HydroSelf flushing system. Therefore water may enter the
storage chambers at any optional point in time (automatically or via external filling).
The hydraulic system is unpressurised in the state of rest. Electrical energy is only
required for a short time for the development of the pressure required to open the
flushing gates.

The Steinhardt HydroSelf Flushing system
Success with a future
Taunusstein September 2006

Steinhardt GmbH,
Röderweg 8-1065232 Taunusstein,
Germany
Telefon +49 (0)6128 9165 0
Fax +49 (0)6128 916527
E-Mail info@steinhardt.dewww.steinhardt.de

HS_HydroSelf FlushingSystem 2006-09-29 GB jöhom.doc - 325 -

11 / 11

Report on the ³Extension of Sewerage System to Everyone who Needs it´ ProjectKenji SAKAI
Construction Technology Research Department, Public Works Research InstituteMinamihara 1-6, Tsukuba city, Japan, 305-8516, ksakai@pwri.go.jp
Abstract: To extend sewerage service to a large population under the tight budgetarycondition, the government of Japan started a project to encourage the application of new
and ambitious ideas to the works of sewerage system. This paper, after the brief
introduction on the state of wastewater management in Japan, describes the project
including results of efforts made for cost reduction, and some cost reduction ideas preparedby PWRI.
Keywords: Sewerage system, Unconnected population, Construction cost, Cost reduction
1. Background and Purpose of the Project
The ratio of the population connected to sewerage system in Japan is 68% at theend of March in 2005, because of the intensive efforts done by the national government,
local governments and related organizations. Wastewater management through seweragesystem has contributed to the improvement of not only everyday life but also water quality
in rivers and seacoasts.
Sewerage system has been constructed mainly in bigger cities and in many local
cities having social needs of such a system. Therefore there exists a difference in connection
ratio to sewerage system among municipalities; the difference has become a kind of social
problem now. There are 24.7 million people left in Japan who are supposed to be covered bysewerage system, but cannot use it at present.
The expenditure on sewerage system construction is expected to be more efficient,because the budgetary conditions of both national government and local governments arequite tight. The national government has started a project to promote sewerage systemconstruction with less cost and less time. In the project, the procedures and the technicalstandards for planning, design and construction of sewerage system are to be revised fromthe viewpoint of cost reduction and time saving.
2. Outline of unconnected population
Figure-1 shows the state of unconnected population. In this paper, ´unconnected
populationµ means the number of people who live in the areas that should be covered bysewerage system but still not due to the delay in construction. The term ´sewerage
populationµ is used for the population that is equal to the sum of unconnected populationand the population that is already covered by sewerage system. In Figure-1, eachmunicipality is classified into seven classes according to the total population size.
- 327 -

㪊㪇㪪㫌㫄㩷㫆㪽㩷㫋㪿㪼㩷㪧㫆㫇㫌㫃㪸㫋㫀㫆㫅㩷㫆㪽㩷㪼㪸㪺㪿㩷㪺㫃㪸㫊㫊㩷㩷㩿㫀㫅㩷㫄㫀㫃㫃㫀㫆㫅㪀The ratio of unconnected
population to total population is
19% in Japan, and 77% of theunconnected population belongs to
the classes of 30 to 500 thousand.
Sewerage population in Japan is
88% of the total population. The
ratio of unconnected population to
sewerage population (uncovered
ratio) is 22% in average in Japan.
Figure-2 shows the relationshipbetween population of each

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㪧㫆㫇㫌㫃㪸㫋㫀㫆㫅㩷㫆㪽㩷㫄㫌㫅㫀㪺㫀㫇㪸㫃㫀㫋㫀㪼㫊㩷㩷㩿㫀㫅㩷㫋㪿㫆㫌㫊㪸㫅㪻㪀㪬㫅㪺㫆㫍㪼㫉㪼㪻㩷㫉㪸㫋㫀㫆㩷㫆㪽㩷㫄㫌㫅㫀㪺㫀㫇㪸㫃㫀㫋㫐䋨䋦䋩municipality and uncovered ratio.
The figure does not include themunicipalities that have nosewerage population, i.e., no planof sewerage system. The biggest
municipality that shows 100% of
uncovered ratio has a populationof 80 thousand. The uncovered
ratio is low in the municipalities
whose population is less than 3
thousand or more than 300
thousand.
From the data mentioned
above, we can assume that theunconnected population in Japanis mainly in the municipalities
whose population is 30 to 500 thousand.

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㪝㫀㪾㫌㫉㪼㪄㪉㩷㩷㪧㫆㫇㫌㫃㪸㫋㫀㫆㫅㩷㩽㩷㫌㫅㪺㫆㫍㪼㫉㪼㪻㩷㫉㪸㫋㫀㫆㩷㫆㪽㩷㫄㫌㫅㫀㪺㫀㫇㪸㫃㫀㫋㫐

3. Efforts toward cost reduction and their results up to now
The government of Japan started the organized program toward cost reduction of
public works in January 1997. In the field of sewerage system construction, national
government published the documents to encourage the efforts toward cost reduction in
1997, and announced action programs in 2001 and 2005.
Among the results up to now, a good example is the revision of the standard for
installation of sewer pipe under public roads. The revision in 1999 allowed sewer pipe to beburied more shallowly than before: Pipes with a diameter of 300 mm or less should becovered at least 60 cm of filling under the surface of roadway and 50 cm under sideway,
while 100 cm was required before the revision.
- 328 -

To evaluate the effect of the efforts toward cost reduction, an installation works ofsewer pipe in K city was taken as an example. The outline of the works is shown in Table-1.
   Table-1 Outline of Installation works of sewer pipe
Items

Content

Diameter

200 mmLength200 m (not straight)

Construction method

Open cut

Gradient of road23 to 72 ̟

Number of connections

20 houses

Related works

Repair of road is included
Temporary displacement of other pipes is excluded

The change in price and wage and the revised design parameters affected the cost.
The cost of the works was estimated under three sets of conditions as listed in Table-2.
Cases-1 and -2 used the same design parameters as the city actually used then, while inCase-3 some parameters were changed to achieve cost reduction.
Table-2 Design parameters for Cost comparison and the results
Design parameters 㧒 Cost

Case-1Case-2Case-3

Year of Price list

1996

2006

2006

Minimum depth of pipe

120 cm120 cm

70 cm

Type of pipe

VU pipe

Plastic rib-pipe

Plastic rib-pipe

Filling material around pipe

Sand (around pipe)+

Sand (under pipe) +Sand (under pipe) +Improved excavated soil

Improved excavated soil

Improved excavated soil

Width of trench

110 cm110 cm85 cm

Width of road base repair

170 cm110 cm85 cm

Retaining wall

Installed

Installed

Not installed

Type of manhole

Type-1 in 7 sites

Type-1 in 7 sites

Type-1

in 1 site

Small type in 5 sites
Curved pipe in 1 site
Depth of inlet to sewer

80 cm

80 cm

60 cm

Total Cost

32.6 million yen

19.5 million yen

12.7 million yen

Cost per pipe length

163,000 yen/m97,400 yen/m63,400 yen/mRelative value of cost

100

60

39

The conditions in detail and the results of calculation are listed in Table-2. From theresults of Cases-1 and -2, the cost in 2006 is estimated to be 60% of the cost in 1996. The
revision on road repair and filling material contributed most to the cost reduction. Iffurther changes were made as indicated in Case-3, the cost would be reduced to 39% of thecost in 1996.

- 329 -

4. Construction Cost of Sewerage System
To promote the project, construction cost of sewerage system was studied. The
average cost can be obtained from the total expenditure and the number of new customers.
From the data of the period from 1998 to 2002, the average construction cost per customer
in Japan is calculated to be 980,000 yen. .
The construction cost per customer can be calculated from the data of themunicipalities that are almost completing construction of sewerage system. Using thenational statistics of 2003, 18 municipalities which satisfy the following conditions wereselected for the study.
Condition-A: Ratio of the population covered by sewerage system to total population
is equal to or more than 80%.
Condition-B: Construction works started after 1990.

㪚㫆㫅㫊㫋㫉㫌㪺㫋㫀㫆㫅㩷㪺㫆㫊㫋㩷㫇㪼㫉㩷㪺㫌㫊㫋㫆㫄㪼㫉㪊㩿㪈㪇 㩷㫐㪼㫅㪆㪺㫌㫊㫋㫆㫄㪼㫉㪀

Condition-C: Both sewers and treatment plants are owned by one municipality.
Condition-D: No investment to rain water control.
Selected 18 municipalities are all located in non-urbanized area, and their population was
1,881 to 17,806 in 2003.
The relationship between㪊㪇㪇㪇
sewer pipe length per㪉㪌㪇㪇customer and construction
cost per customer of both㪉㪇㪇㪇
sewersandsewerage㪈㪌㪇㪇
system in 18 municipalities
is shown in Figure-3. Linear㪈㪇㪇㪇㪚㫆㫊㫋㩷㪽㫆㫉㩷㫊㪼㫎㪼㫉㪸㪾㪼㫊㫐㫊㫋㪼㫄
relation can be obtained for㪚㫆㫊㫋㩷㪽㫆㫉㩷㫊㪼㫎㪼㫉㫊㪌㪇㪇
both. In the case of 10 m percustomer, the construction
㪇
㪇
㪌
㪈㪇
㪈㪌
㪉㪇
㪉㪌
cost per customer is 1.5㪪㪼㫎㪼㫉㩷㫇㫀㫇㪼㩷㫃㪼㫅㪾㫋㪿㩷㫇㪼㫉㩷㪺㫌㫊㫋㫆㫄㪼㫉㩷㩿㫄㪆㪺㫌㫊㫋㫆㫄㪼㫉㪀million yen for seweragesystem, and 1 million yen㪝㫀㪾㫌㫉㪼㪄㪊㩷㩷㪪㪼㫎㪼㫉㩷㫇㫀㫇㪼㩷㫃㪼㫅㪾㫋㪿㩷㪸㫅㪻㩷㪚㫆㫅㫊㫋㫉㫌㪺㫋㫀㫆㫅㩷㪺㫆㫊㫋for sewers. The construction
cost of sewers per unit length in the studied 18 municipalities is 100 thousand yen permeter on average.
5. Cost to be balanced with customers¶ charge
One of the important points for setting the target of construction cost is to balance
investment with income. A trial calculation to balance capital investment with customers·
charge was done using the data of the municipalities practicing good seweragemanagement. The conditions of calculation and the results are listed in Tables-3 and -4
respectively. The construction cost per customer that is balanced with customers· charge
under the conditions of Table-3 is 766 thousand yen in the case that interest rate is 3%.
- 330 -

Table-3 Conditions of Calculation
Items

Conditions

Customers· charge

200 yen/m3-wastewater

Maintenance cost

80 yen/m3-wastewater

Water consumption

0.25 m3/d/customer

Coverage by charge

Maintenance cost + half of Capital cost

Ratio of bond

50%, 60%, 70% of Total Investment

Interest rate

2, 3, 4%

Table-4 Calculated cost ( in 103 yen/customer)
Interest rate

Ratio of bond
50%

60%

70%

2%

858

715

613

3%

766

638

547

4%

688

573

491

6. Promotion of the project
To promote the project, in September 2006 all the municipalities were asked to makeproposals that contribute to the cost reduction in sewerage works of each municipality for
unconnected people, and to try them in actual works. Municipalities can propose any ideas.
The national government will choose both the acceptable ideas and the municipalities thatwill try them in actual works. After being constructed, these ideas will be evaluated byrelated municipalities, the national government and PWRI from the viewpoint of both cost
reduction and the applicability to other municipalities.
Our institute prepared a list of ideas for reference that is shown in Table-5. The listed
ideas were mainly taken from the answers to the questionnaire survey conducted in 2003.
Table-5 List of ideas for reference prepared by PWRI
Ideas

Description in present standards

Use of inverted siphon

No use in principle

Setting of sewer gradient at a starting point No description
by velocity of 60 cm/s under half full flow
Raise of upper limit of velocity in sewer

3m/s

Reduction of gradient of house connection

2/100 for a connection of less than 150
customers

Use of curved pipe

Not allowed

Raise ofmanholesmaximum

distance

between 75 m for a pipe diameter under 600 mm

Reduction of diameter of inlet to sewer

20 cm or more

Reduction of HRT of bioreactor

24 hrs for Oxidation ditch- 331 -

Inlet 䇭Manhole
Outlet 䇭Manhole
Among the ideas in Table-5,
two examples, inverted siphon
and curved pipe are explained
briefly.
Figure-4 is a structuredrawing of inverted siphon thatis utilized to sanitary sewer in T
city. The slope of bothFigure-4 Structure drawing of inverted siphon
descending and rising pipe isusually 1 to 1 (vertical to horizontal)
in Japan. Deposits such as sand or
small stone accumulated in inverted

siphoncanbecleanedbywater-jetting. By use of inverted
siphon, downstream sewer pipe canbe buried more shallowly, or
manhole type pumping stations can
be avoided.
Figure-5 is a part of sewer
network map of K city. In several
points of change of sewer direction,
curved pipes are utilized instead ofmanholes. The angles of the curved
pipes utilized in Figure-5 are 5.625,
11.25, and 22.5 degrees. These
curved pipes were manufactured in䋺 site of cur䌶ed pipe
factory.
Recently a new type of curved Figure-5 Use of curved pipe in K citypipe was developed; a curved plastic
rib-pipe as shown in Figure-6.
The results of the project will help not only
the extension but also the reorganization ofsewerage system.
Figure-6 Curved Plastic Rib-pi pe- 332 -

- 333 -Ｔo extend sewerage system quickly
to everyone who needs it
Reducing both cost and time of
construction
By new and ambitious ideas forplanning, design and construction

Purpose of the Project

Public Works Research InstituteKenji SAKAI

project“Extension of Sewerage System
to Everyone who Needs it”

4. Promotion of the project

3. Construction cost of Sewerage System

2. Efforts toward cost reduction up to now

1. State of Wastewater Management

Overview

３．Increasing needs torenewal & rehabilitation of facilities

２．Tight budgetary conditions ofboth national & local governments

１．Existence of 24 million people
who are waiting for sewerage system

Background of the project

0

5

10

15

20

25

30

1

0<

-

30

-

50

50

-

70

70

-1

10

00

0-

2
20

00
0-

3
30

00
0-

5
0
50

00
-1

0

00
10

0

0<

Population of municipalities (in thousand)

10

30

OthersUnconnected
Connected

Distribution of unconnected population

・ Unconnected population: Population to be covered by seweragesystem, but not now

・ Connected population: Population covered by sewerage system

Definition of the terms

Sum of the Population ofeach class (in million)- 334 -

Summary of the state ofUnconnected population

68%

Sewerage System(Connected)
Sewerage System(Unconnected)
On-site system &othersbelongs to the municipalities of
10 to 500 thousand in population.

• Ratio: 19% of the total population in Japancannot use sewerage system.
• Distribution:
89% of the unconnected population

19%

13%

State of Wastewater Management in 2004

- 335 -• In 2001 & 2005, Action programs toward
cost reduction of sewerage systemconstruction.

L=200 m, D=200 mm

Plan of sewer pipe installation in K city

Example：・ Installation of sewer pipe by open cut
method・ Diameter 200 mm, Length 200 m
・ Gradient of road 23～72 ‰Method:・ Calculate the cost under the conditions
adopted in 1996 and 2006 by K city,and proposed in 2006 by PWRI

Case study for cost comparison• Minimum depth for small pipe
BeforeAfter
100cm → 60cm under roadway
50cm under sideway

Change of the cost in 10 years• Small pipe (with a diameter of 300 mm or less)can be buried more shallowly than before.

pipe installation under public roads in 1999

:Revision of the standard for

An Example of the results up to now• In 1997, Program toward cost reduction of
public works.
Documents to encourage cost reductionof sewerage system construction.

Efforts toward Cost Reduction up to now
by the national government

- 336 -

1.2 m

VU

Minimum depth of pipe

Type of pipe

Installed

Type-1Retaining wall

Type of manhole

In 1996

Pipe

80 cm

Type-1

Installed

110 cm110 cmIn 2006 + proposal

Sand

Sand

In 2006

Improved excavated soil

60 cm

& Curved pipe

Type-1, Small,

Not installed

85 cm

85 cm

Sand

Improved excavated soilRoad base

Asphalt

Sand

Rib-pipe

0.7 m

2006

Case-3

Improved soil Improved soil

Sand

Rib-pipe

1.2 m

2006

Case-2

Revision of road repair
and filling material

80 cm

170 cmDepth of inlet to sewer

110 cmWidth of road base repair

over pipe up to 30 cm

Width of trench

Sand

Sand

under pipe

Filling material

1996

Year

Case-1

Design parameters for cost comparison

Relative value(EUR/m)100(1,087)

Total cost
32.6
(million yen)
Cost per unit length(yen/m)163,000

Case-1

59.8

(649)

97,40019.5

Case-2

38.9

(422)

63,400

12.7

Case-3

Small type in plastic

D= 300mm

Results of cost comparison

Type-1 (ordinary type)

D= 600mm

Type of Manhole

0

500

1000

1500

2000

2500

3000

0

10

15

Pipe length per customer (m/customer)

5

20

Cost forsewerage system
Cost for sewers

Sewer pipe length and construction cost

2. Cost in the municipalities that arealmost completing construction(6,500EUR/customer)25

1. Average cost in Japan (1998 to 2002): 980,000 yen/customer(Cost = investment /new customers)

whole sewerage system

Construction cost of

C onstruc tion c ost p e r cu stom e r(1 0 3 y e n /c u stom e r)

- 337 -

Trial calculation was doneusing the data of the municipalities
practicing good sewerage management.

One idea is
to balance construction cost withcustomers’ charge.

Target of construction cost

Conditions for selection
A: Ratio of connected population tototal population is 80% or more
B: Construction works started after 1990
C: Both sewers and treatment plants are
owned by one municipality
D: No investment to rain water control
Characteristics of selected 18 municipalities: Located in non-urbanized area
: Population of 1,881 to 17,806 in 2003

Selection of municipalities- 338 -80 yen/m3-wastewater

200 yen/m3-wastewater

Conditions

・ Construction of sewerage systemusing revised methods

・ Evaluation of the ideas:
Cost and Applicability to other municipalities

・ Selection of the ideas andthe municipalities which will do them・ Proposal from municipalities & private companies

Promotion of the project

0.25m3/d/customer
Maintenance cost +half of Capital cost
Ratio of bond/investment 50, 60, 70%
Interest rate
2, 3, 4%

Customers’ charge
Maintenance cost
Volume of wastewater
Coverage by charge

Items

Conditions of Calculation

638
573

766
688

3%
4%

491

547

613

70%

・Reduction of diameter of inlet to sewer
・Reduction of HRT of Bioreactor

Others・Use of curved pipe
・Use of small manhole
・Raise of maximum distance between manholes

Reduction of manholes

・Use of inverted siphon
・Raise of upper limit of velocity in sewer
・Reduction of gradient of house connection

Ｓｈａｌｌｏｗ installation

List of ideas presented by PWRI

715

60%

858

50%

Ratio of bond/investment

2%

Interest rate

(thousand yen/customer)

Calculated cost- 339 -I

8 months of operation, 3 houses discharged

Exit pipe from inlet manholeof inverted siphon

Channel1 year of operation, 5 houses discharged

Exit pipe from inlet manhole

L= 8.5 m

Box culvert for rain water
H= 2.37 m

Outlet Manhole

Inlet Manhole

Inlet chamber

Outlet chamber

Improved type of inverted siphon

Conventional type of Inverted siphon
in Japan- 340 -: site ofcurved pipe

Curved Plastic Rib-pipe

Use of curved pipe in K city

Route of steep sewer

Residential area on the hill

Use of steep sewer to connect the area on the hillin Ohtsu city

Curved pipe

Curved pipe in construction site- 341 -Energy absorber for steep sewer（Stilling pond)

Mean gradient = 420 ‰402 m

H= 170 m

170 m

Cross section view of steep sewer in Ohtsu city

H= 7.4 m

Drop shaftof sewerage system.

the extension and the reorganization

The results of the project will help both

Prospects

Stilling pool
Stilling pool

Energy absorbers utilized for steep sewerin Ohtsu city

- 342 -Thank you for your attentionDipl.-Ing. Ralf Steeg
Abstract
Nowadays, the domestic water management services in highly industrialised
countries have to deal with matters that go far beyond the “original” tasks of a few
decades ago. Whereas, in the past, the domestic water utilities were primarily
concerned with the technical aspects of water supply and disposal, they are now
forced to focus on urban development matters, for instance the improvement of thequality of life, the development of tourism and the maintenance of resources.
Residents no longer look upon their communities as purely administrative entities or
economic areas, but rather as their areas of life that have to be developed andmaintained. Towns and cities must present themselves as service providers for the
inhabitants. They must attract companies, moneyed newcomers and tourists. This
increases the attention that must be devoted to water management. Clean andecologically sound rivers and lakes have become important areas of activity for thisbranch of science and an elementary precondition for a high quality of life. Yet, until
now, the condition of many waters must be regarded as very unsatisfactory.
One of the principal sources of urban water pollution is the introduction of waste
water from the combined sewage system where domestic waste water is conducted
off together with the rain water that has drained off the streets. During severe
rainstorms the sewage system becomes flooded on account of its limited capacity
resulting in untreated sewage being swept into open waters.
In Germany this manner of pollution accounts for 40% of water contamination. In
Berlin, alone, up to seven million cubic meters of waste water are introduced into theRiver Spree every year.
There are many proven systems to diminish this form of contamination. They include
planning-intensive decentral measures such as roof landscaping and seepage
systems or centralised solutions such as cost-intensive underground rainwatercollecting overflow basins.
The LURITEC System
This is where LURITEC offers a new, cost-effective technology that can be rapidly
implemented. Collecting containers made of plastic and steel are positioned directlyin front of pipeline outlets that lead into open waters. The technical equipment of“conventional” storage systems (e.g. pumps and computer technology) takes on amodel function that can be combined with the new storage system which is supplied
ex works as a modular kit for rapid and easy installation eliminating elaborate
preparations and prolonged planning.
In addition to waste-water storage, these containers with their surfaces above waterlevel can fulfil numerous other functions. They can be usedas public parks andbiotopes, or for bars, cafés and exhibition pavilions. Moreover, these newly created“islands in the water” can be let or leased and thus help finance the storage system.
Innovative environment protection does not entail any losses, but rather contributes
to the direct addition of value to urban quality: The proper and effective use of urban
areas helps to finance the protection of the waters.

- 343 -

Now that a team of architects, town planners, creative artists, biologists and water
scientists have confirmed the technical, economic and architectural feasability of thisproject, it is planned to set up a pilot installation alongside Berlin’s River Spree in2007.

- 344 -

Present status and estimation method of pollutant load in wet
weather flow from urban areas

Yoshida, T.* and Tamoto, N.*** Senior Researcher, Wastewater System Division, Water Quality Control Department, National Institute for Landand Infrastructure Management, Ministry of Land, Infrastructure and Transport, Government of Japan, Address:
Asahi 1, Tsukuba, Ibaraki 305-0804, Japan, Email: yosida-t92e5@nilim.go.jp** Researcher, Wastewater System Division, Water Quality Control Department, National Institute for Land andInfrastructure Management, Ministry of Land, Infrastructure and Transport, Government of Japan, Address: Asahi
1, Tsukuba, Ibaraki 305-0804, Japan, Email: tamoto-n92ta@nilim.go.jp
Abstract This paper describes Japanese present status of controlling nonpoint source pollution from urban areas,
the field survey on urban pollution load and the related load estimation method. Promotion of point source control
has increased a relative importance of nonpoint source control, however urban nonpoint pollutant load throughseparate sanitary sewers are not yet fully addressed, while drastic measures on combined sewer overflows
alleviation were initiated in Japan. Then, the current framework and status of urban nonpoint pollution control werereviewed, and the field survey was conducted targeting on conventional water qualities, heavy metals, endocrine
disrupting chemicals, and so forth. The estimation method of urban nonpoint pollution load was also investigatedsuch as a use of prior dry weather days as an independent variable. This research began in fiscal 2004 and isongoing.
Keywords nonpoint source, nonpoint pollution, pollution load, field survey, estimation method

Introduciton
Promotion of point source control has increased a relative importance of nonpoint source control, however
nonpoint pollution are not yet fully addressed in Japan. Sewage works and other water pollution controls had
focussed on point sources, which contributed to conservation or restoration of ambient water quality, still theachievement ratio of water qualtiy standards are not satisfactory especially in closed water bodies in the nation.
In terms of watershed management, nonpoint pollution control should be considered for control efficiency.
Urban nonpoint pollution loads are to be mainly tackled through sewage works, but pollution loads fromseparate storm sewers has not been vigorously controlled while combined sewer overflows (CSOs), inclusive of
urban nonpoint pollution loads, have become a target of controls. New goals for CSOs control are to reduce thepollution loads under the level of separate serwer systems, to halve the overflow events from stormwater outlests
to satisfy secure in terms of public health, and to eliminate the debris. Subsequently, the Enforcement Order ofSewerage Law was amended to set technical standards of stormwater outlets structure such as weir height andscreen installation as well as wet weather water quality standard for CSOs (BOD 40mg/l) and monitoring
requirement of CSOs at least once a year for BOD. Also, the relevant manuals of planning and monitoring were
formulated, the national programs for CSOs control were initiated to subsidise the control projects, and thespecial research and development project were conducted (Sakakibara et al., 2005). On the other hand, runoff
from separate storm sewers is not distinctly a target of control, unlike the Stormwater National Pollutant
Discharge Ellimination System (NPDES) permit in the United States. Comprehensive Basin-wide Plans for
Sewage Works (CBPSW) in Japan perform as high-ranking schemes of sewage works, and set allocate allowable- 345 -

pollution load to each pollution source including urban nonpoint source (JSWA, 1999). In practice, however,allowable pollution loads could not be necessarily allocated to the urban nonpoint source pollution in an
effectively manner. Though "Tentative Guideline on Urban Nonpoint Pollution Control" (MLIT and JIWET,
2002) provides the relevant technical information on planning and related researches in accordance withhigher-ranking schemes such as CBPSW, there could be room for further knowledge and technical improvement
to better planning and the related researches.
Overall, urban nonpoint pollution load through separate sanitary sewers are not yet fully addressed in Japan, andfurther knowledge and technical improvement could serve for better planning and the related researches.
Especially, quantification of runoff pollution loads from urban areas and load reduction by control measures is a
key aspect. Then, the current framework and status of urban nonpoint pollution control were reviewed, and thefield survey was conducted targeting on conventional water qualities, heavy metals, endocrine disrupting
chemicals, and so forth. The estimation method of urban nonpoint pollution load was also investigated such as ause of prior dry weather days as an independent variable1.

Methods
Current framework and status
The current frameworks and status of urban nonpoint pollution control were reviewed mainly through theliterature. The relevant planning based on laws, the supporting documents, and the financial programmes areincluded in this review.
Field survey
Field surveys were conducted in three study sites; Drainage areas A, B and C. Their profiles are shown in Table
1. Each drainage area is located in an urban area served by a separate sewer system in the same prefecture. The
impervious area ratio of each drainage area was estimated to be around 60%. The surveys were carried out at thestorm sewer outlets of three drainage areas simultaneously during the same rainfall, concerning four rainfall
events as of the end of the fiscal 2005. To clarify the runoff characteristics and to calculate the pollution loads,
the rainfall close to the sampling point and the flow rate at the sampling point were also measured.
The sample was obtained by manually taking 14 to 20 bottles from each investigation point. The water quality
constituents that were analyzed were SS, VSS, BOD, CODMn, TN, and TP, but some surveys also analyzed thesamples for their content of heavy metals (copper, zinc, lead, cadmium) plus Benzo [a] pyrene (B(a)P) andBisphenol A (BPA). At the same time as the sampling, turbidity and electric conductivity (EC) were measured
with water quality sensor.2
Load estimation method
To enhance the reliability and to facilitate easier estimation methods, a regression method was researched. The
runoff load was produced by pollutants accumulated on the ground surface then washed off by rainwater. Suchpollutants consist of atmospheric depositions, tire scraps, fallen leaves, and other waste materials, and thefriction velocity when they are transported varies according to rainfall and rainfall intensity. Thus,
meteorological and precipitation conditions are assumed to be the major factors that determine the runoff load ineach drainage area. In emulation of the method of Nakamura (1993), multiple regression analyses were
performed with the rainfall and the prior dry weather days for each event as the explanatory variables (Eq. 1) inorder to predict the runoff load. The data of the said field survey was used for the analysis.
1

The contents of the field survey and the load estimation method was derived from Fujiu et al. (2005), Fujiu et al. (2006),
Tamoto and Yoshida (2005), Tamoto et al. (2005), and Tamoto et al. (2007).
2
Not all measured water quality data are described in this paper for lack of space.

- 346 -

Table 1 Profile of Study Sites
Area (ha)Impervious area ratio

Drainage area A

95

69%

Drainage area B
Drainage area C

18
67

67%
61%

Land use
High/medium-rise residential
Commercial
Residential
Residential

Arterial roads
Included
Included
Not included

L = a･Σr + b･NDD ------------------------------------------------------------------------------------Eq. 1(where L: Specific load per rainfall event (kg/ha); Σr: total rainfall per event (mm); NDD: Number ofprior dry weather day (day); a, b: constants)

Results and Discussion
Current framework and status
Runoff from separate storm sewers is not distinctly a target of control. Comprehensive Basin-wide Plans for
Sewage Works (CBPSW) in Japan perform as high-ranking schemes of sewage works, and set allocate allowablepollution load to each pollution source including urban nonpoint source (JSWA, 1999). In practice, however,allowable pollution loads could not be necessarily allocated to the urban nonpoint source pollution in an
effectively manner. In formulation of CBPSW, at first, generating loads including non-point source on awatershed are estimated using unit pollution load data, and runoff loads are calculated through pollution analysis.
Secondary, the allowable load is calculated based on the water quality standard at a target point in the concernedwater body, and the pollution load that should be reduced, referred to as the reduction load, is determined as adifference of the total generating load and the allowable load. Lastly, the reduction load is distributed to eachpollution source category such as public sewerage, industrial, livestock, and non-point source (e.g. urban, farm).
On the estimation process of generating loads of urban non-point source, existing data in other watersheds are
frequently applied instead of collecting data for a target watershed for the reasons of costs and the difficulty of
performing field surveys. In CBPSW, unit loads are used for most sources, and the unit loads of urban nonpoint
pollution shown in JSWA (1999) are as in Table 2.
As a technical guidance, "Tentative Guideline for Urban Nonpoint Pollution Control" (MLIT and JIWET,
2002) was published for providing the knowledge of urban nonpoint pollution control as well as the relevant
planning and research methods. The Guideline includes detailed description in accordance with higher-ranking
schemes such as CBPSW, however it could have been scarcely referenced in practice. This situation, with urban
nonpoint pollution allocation practices in CBPSW, could indicate that there is room for further knowledge andtechnical improvement to better planning and the related researches.
For promotion of nonpoint pollution control, financial support programmes from the national government are
prepared by the name of "Program of Supporting Next Generation Sewerage Project." Still, the adopted projects
are limited as is shown in Fig 1.
Overall, urban nonpoint pollution load through separate sanitary sewers are not yet fully addressed in Japan, andfurther knowledge and technical improvement should be sought to better planning and the related researches.

Program of Supporting Next
Generation Sewerage Project

Water Environment
Creation Project
Recycle Promotion
Project
Function Upgrade
Promotion ProjectType of Water Circulation Restoration(178)
Type of Nonpoint Pollution Control(3)Type of Recycled Resources Utilisation(163)
Type of Potential Energy Utilisation(7)
Type of New Technology Utilisation(30)
Type of Advanced IT(15)(Number of projects adopted from fiscal 1996 to 2005)

Fig 1 Program of Supporting Next Generation Sewerage Project with Number of Adopted Projects- 347 -

Table 2 Unit Loads of Urban Nonpoint Source
Research
Organisation

Research area
Municipality

Drainagearea (ha)Unit load (kg/ha/year)
SS

BOD

CODMn

middle-size city
13.69
735
191
34
large-size city
17.17
562
166
102
Kitakyushu city
2,390
605
378
Kobe city
1,304
168
208
Environment Agency
Yamagata city
904
102
90
Chiba city
105
59
55
Public Works
17.17
1,134
167
159
Kobe city
Research Institute
26.75
755
41
101
Shiga town
46.71
151
39
53
Otsu city
66.18
210
24
34
Japan Institute of
Chino city
7.81
435
157
222
Wastewater
Okaya city
5.5
1,410
87
126
Engineering
Abiko city
15.88
183
36
45
Technology
Ushiku city
67
314
28
43
Tsukuba city
5.26
463
53
71
Ibaraki Prefecture
42.7
Shiga Prefecture
52.6
102.6
Max
2,390
605
378
Min
105
24
34
Mean
737
128
107
Note : Extracted from Guidline and Comentary on CBPSW. "-" means not described.
Saito and Okazawa

T-N
4.5
14.1
33.5
34.2
17.6
19.1
23.1
11.1
8.5
6.4
39.6
11.1
11.6
5.0
7.8
5.5
14.1
25.0
39.6
4.5
16.2

T-P

Estimation method

1.6
1.3 Product of annual average
6.5 concentration, annual
5.8 precipitation, and runoff
3.0 percentage
0.9
1.9
0.9
Summation of pollution
1.9
loads per rainfall event,
0.7
which are estimated with
3.0
correlation equation between
2.7
event precipitation and runoff
0.9
load
0.6
0.8
0.55 0.73 0.89 6.5
0.6
1.9

Field survey
Characteristics of the observed rainfalls are described in Table 3. Selected constituents concentration of eachstudy site in Rainfall 3 is shown in time series in Fig 2 to Fig. 4. Concentration varies by order of magnitude,
corresponding to the rainfall runoff flow. First flushes are observed with their variation of degree among
constituents and drainage areas.
In order to characterise concentrations of rainfall runoff, which can vary widely during a storm event, Event
Mean Concentrations (EMCs) were calculated (Table 4). Comparison with Environmental Quality Standards(EQSs) (EA, 1971) or Predicted No Effect Concentrations (PNECs) (MOE, 2003) shows EMCs of almost all
constituents exceed EQSs or PNECs, and they could have not an ignorable effect on receiving waters. Especially,
EMC of zinc, recently incorporated into EQSs, is larger than the standard almost by order of ten. EMC of BPA ismuch lower than PNEC while EMC of B(a)P exceeds PNEC. Overall, though not so heavily polluted, rainfall
runoff through storm sewers could be a source of ambient water quality degradation.
Specific load per rainfall event are shown in Table 5. The variation of specific loads is also observed among
different rainfalls similarly to EMCs. The analysis of relationship between specific loads, and total precipitationor number of prior dry weather days shows a tendency of good linear relationship, which leads to the load
estimation method of using multiple regression.
Table 3 Characteristics of Observed Rainfalls
Rainfall 1
Rainfall 2
Rainfall 3
Rainfall 4
NDD
Total
Max
NDD
Total
Max
NDD
Total
Max
NDD
Total
Max
(d)
(mm) (mm/hr)(d)(mm) (mm/hr)(d)(mm) (mm/hr)(d)(mm) (mm/hr)
Drainage area A
7
14.0
2.5
10
6.0
2.5
63
37.5
11.0
3
16.5
6.0
Drainage area B
7
15.0
3.5
10
9.5
2.5
63
42.5
10.5
Drainage area C
7
14.5
3.0
10
8.0
2.5
63
34.0
9.5
12
13.5
5.5
Note ; NDD: Number of prior dry weather days (d), Total: Total precipitation (mm), Max: Maximum precipitation intensity(mm/hr), "-" measn field survey was not conducted.

- 348 -

800

600

600

400

400

200

200

0

0

13:00

15:00

17:00

19:00
Time

21:00

5

0

4

2

3

4

2

6

1

8

0

10

Precipitation(mm/30min)

SS(mg/l)800

Flow(m3/s)

1000
SS
CODM nZn

CODMn(mg/l), Zn(mg/l x100)

1000

13:0015:0017:0019:0021:0023:00 1:00
Time
Precipitation
Flow

23:00

Fig 2 Runoff Concentration and Flow of Rainfall 3 from Drainage Area A

80

300

60

200

40

100

20

0

0

13:00

15:00

17:00

19:00
Time

21:00

5

0

4

2

3

4

2

6

1

8

0

10

Precipitation(mm/30min)

SS(mg/l)400

Flow(m3/s)

100
SS
CODM nZn

CODMn(mg/l), Zn(mg/l x100)

500

13:0015:0017:0019:0021:0023:00
Time
Precipitation
Flow

23:00

Fig 3 Runoff Concentration and Flow of Rainfall 3 from Drainage Area B

80

600

60

400

40

200

20

0

0

13:00

15:00

17:00

19:00
Time

21:00

23:00

5

0

4

2

3

4

2

6

1

8

0

10

13:0015:0017:0019:0021:0023:00
Time
Precipitation

Fig 4 Runoff Concentration and Flow of Rainfall 3 from Drainage Area C- 349 -

Flow

Precipitation(mm/30min)

SS(mg/l)800

100

Flow(m3/s)

SS
CODM nCODMn(mg/l), Zn(mg/l x100)

1000

Table 4 Event Mean Concentrations of Urban Runoff

Drainagearea C

Drainagearea B

Drainagearea ASS
BOD CODMn
TN
TP
Cu
Zn
Pb
Cd
BPA
B(a)P
(mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (μg/L) (μg/L)
Rainfall 1
66
12.8
15.5
2.9
0.30
0.07
0.008
0.001
0.21
0.007
Rainfall 2
86
19.8
29.3
4.0
0.51
0.06
0.35
N.D.
N.D.
0.23
0.025
Rainfall 3
72
11.2
23.5
2.4
0.27
0.27
1.10
0.006
N.D.
0.08
0.011
Rainfall 4
62
5.4
12.0
2.0
0.22
0.03
0.25
0.021
0.004
Mean
71
12.3
20.1
2.8
0.32
0.12
0.44
0.009
0.001
0.17
0.015
Rainfall 1
27
4.0
5.7
2.1
0.12
0.00
0.04
2.300
3.354
0.11
0.018
Rainfall 2
83
21.3
28.9
3.3
0.25
0.04
0.38
0.015
N.D.
0.67
0.041
Rainfall 3
84
6.5
11.0
2.1
0.24
0.20
0.38
0.000
N.D.
Mean
65
10.6
15.2
2.5
0.20
0.08
0.26
0.772
1.118
0.39
0.030
Rainfall 1
31
4.6
9.0
2.1
0.12
0.03
0.09
N.D.
N.D.
0.08
0.014
Rainfall 2
54
12.4
20.2
2.4
0.16
0.05
0.14
0.001
N.D.
0.16
0.033
Rainfall 3
68
7.0
11.4
1.6
0.19
Rainfall 4
29
3.2
6.5
1.7
0.07
0.12
0.07
0.014
0.003
Mean
46
6.8
11.8
1.9
0.14
0.07
0.10
0.005
0.001
0.12
0.023
EQS
25
(2, 3)(3, 5) (0.4, -) (0.03, 0.05)
0.03
0.01
0.01
PNEC
11
0.005
Note : "N.D." means not detected. "-" means deficiency, not measured, or not applicable. In EQS of BOD, CODMn, TN, and TP, (, ) means (EQS of receiving water of Drainage areas A and B, EQS of receiving water of Drainage area C).

Table 5 Specific Loads of Urban Runoff

Drainagearea C

Drainagearea B

Drainagearea A

CODMn
SS
BOD
TN
TP
Cu
(kg/ha) (kg/ha) (kg/ha) (kg/ha) (kg/ha) (g/ha)
Rainfall 1
3.83
0.751
0.908
0.172 0.0174
Rainfall 2
2.25
0.519
0.767
0.104 0.0135
1.6
Rainfall 3
22.95
3.566
7.478
0.763 0.0845
84.6
Rainfall 4
4.44
0.382
0.852
0.145 0.0156
1.8
Mean
8.37
1.304
2.501
0.296 0.0327
29.3
Rainfall 1
0.17
0.026
0.037
0.013 0.0008
0.0
Rainfall 2
0.47
0.122
0.165
0.019 0.0014
0.2
Rainfall 3
1.34
0.103
0.175
0.033 0.0039
3.2
Mean
0.66
0.083
0.126
0.022 0.0020
1.1
Rainfall 1
0.14
0.020
0.040
0.009 0.0005
0.1
Rainfall 2
0.27
0.063
0.103
0.012 0.0008
0.3
Rainfall 3
2.21
0.226
0.372
0.051 0.0061
Rainfall 4
0.32
0.035
0.071
0.019 0.0008
1.3
Mean
0.73
0.086
0.146
0.023 0.0021
0.6Note : "N.D." means not detected. "-" means deficiency, or not measured.

Zn(g/ha)
4.4
9.1
349.2
17.8
95.1
0.2
2.2
6.0
2.8
0.4
0.7
0.7
0.6

Pb
(g/ha)
0.49
N.D.
1.87
1.53
0.97
0.02
0.09
0.00
0.03
N.D.
6.18
0.16
2.11

Cd
BPA
B(a)P
(g/ha) (mg/ha) (mg/ha)
0.035
12.04
0.42
N.D.
6.05
0.65
N.D.
24.79
3.65
0.250
0.071
14.29
1.58
0.022
0.73
0.12
N.D.
3.84
0.23
N.D.
0.007
2.28
0.18
N.D.
0.35
0.06
N.D.
0.84
0.17
0.029
0.010
0.59
0.11

Load estimation method
Using the data of the field survey in Drainage areas A and C, multiple regression analyses were conducted for SS,
BOD, CODMn, TN, TP, and zinc according to Eq. 1. The regression result is summarised in Table 6, and thecomparison between the measured and estimated values are shown in Fig 5 and Fig 6. The comparison revealed
that regardless of the drainage areas, the estimated values conformed with the measured values in most cases.
Generally, there are several principal estimation methods for urban nonpoint pollution loads as shown in Table 7.
In Method (1), average annual concentration of runoff is calculated from several EMCs, and that multiplied byrunoff percentage and annual precipitation is an estimation of annual unit load. In Method 2, field survey isconducted in each land use such as roof and road, and a runoff load is summed up. Method (3) reflects eachrainfall event, so does Method (4) with prior dry weather days considered. Regardless of methods, more data
produce more reliable estimation results, and it is desirable that more appropriate data are obtained. In terms of
the fact that Methods (1) and (2) do not explicitly consider meteorological or hydrological information in eachrainfall event, Methods (3) or (4) could have more reliable estimation results with not a large data required. The
above analysis adopted Method (4), which suggested that the method is a viable option, and more dataacquisition and analysis are ongoing.

- 350 -

25

4

20
15
10
5
0

10
Estimated CODMn (kg/ha)

5
Estimated BOD (kg/ha)

Estimated SS (kg/ha)

30

3
2
1

6
4
2
0

0

0

5

10

15

20

25

30

0

1

M easured SS (kg/ha)

2

3

4

0

5

1

0.5

0.8

0.8

0.4

0.4
0.2

Estimated Zn (kg/ha)

1

0.6

0.6

0

0.2

0.4

0.6

0.8

0.4
0.2

6

8

10

0.2
0.1
0

0

1

4

0.3

0

0

2

M easured CODM n (kg/ha)

M easured BOD (kg/ha)

Estimated TP (kg/ha)

Estimated TN (kg/ha)

8

0.2

0.4

0.6

0.8

1

0

0.1

M easured TP (kg/ha)

M easured TN (kg/ha)

0.2

0.3

0.4

0.5

M easured Zn (kg/ha)

0.3

2.5

0.25

2
1.5
1
0.5

0.5
Estimated CODMn (kg/ha)

3
Estimated BOD (kg/ha)

Estimated SS (kg/ha)

Fig 5 Comparison of Measured and Estimated Values (Drainage area A)

0.2
0.15
0.1
0.05

0

0.5

1

1.5

2

2.5

0

3

0.05 0.1 0.15 0.2 0.25 0.3
M easured BOD (kg/ha)

0.1

0.01

0.08

0.008

Estimated TP (kg/ha)

Estimated TN (kg/ha)

M easured SS (kg/ha)

0.06
0.04
0.02

0.3
0.2
0.1
0

0

0

0.4

0

0.1

0

0.02 0.04 0.06 0.08
M easured TN (kg/ha)

0.1

0.006
0.004
0.002

0

0.002 0.004 0.006 0.008 0.01
M easured TP (kg/ha)

Fig 6 Comparison of Measured and Estimated Values (Drainage area C)- 351 -

0.3

0.4

M easured CODM n (kg/ha)

0

0

0.2

0.5

Table 6 Result of Regression
Drainagre a (kg/ha/mm)
area A b (kg/ha/day)Drainage a (kg/ha/mm)
areaC b (kg/ha/day)

SS
0.211
0.243
-0.01200.0414

BOD
0.021
0.046
-0.0003
0.0038

CODMn
0.025
0.106
0.00050.0057

TN
0.00770.00770.000650.00048TP
Zn
0.0174-0.0010-0.0050
0.0062-0.00003 0.00011 -Table 7 Principal Estimation Methods for Pollution Loads
No.

MethodProductofannualaverage(1) concentration, annual precipitation,and runoff percentage(2)

Summation of pollution loads fromeach land use area

Equation∑L=k･C･∑R∑L=(1/A)･∑(Di･Li･Ai)

Summation of pollution loads per
rainfall event, which are calculated(3)with correlation equation between
event precipitation and runoff load-

Summation of pollution loads per(4) rainfall event, which are calculatedwith multiple regression equation

L=a･∑r＋b･NDD

Notation∑L: Unit load (kg/ha/year)
k: Runoff percentage
C: Annual average concentration (kg/ha/mm)∑R: Annual precipitation (mm/year)
A: Catchment area (ha)Di: Runoff coefficient for land use "i" for pollution
at the concerning point
Li: Pollution load from land use "i"Ai: Area of land use "i" in catchment area (ha)
L: Pollution load per a rainfall event (kg/ha)∑r: Event precipitation (mm)a, b: Coefficients in multiple regression equation
NDD: Number of prior dry weather days (day)Conclusion
The Japanese current framework and status of urban nonpoint pollution control was reviewed, and it was pointed
out that the control has not yet been vigorously addressed though there are a planning framework, a technicalguidance, and a financial programme to support the control. Further knowledge and technical improvement
should be sought to better planning and the related researches.
Field survey was conducted, focusing on the clarification of the state of runoff of conventional constituents,
heavy metals and endocrine disrupting chemicals. It revealed that concentration in time series varied by order ofmagnitude, corresponding to the rainfall runoff flow, and runoff quality characteristics varied among drainage
areas. EMCs of almost all analysed constituents exceeded EQSs or PNECs, and they could have not an ignorable
effect on receiving waters.
A load estimation method was researched based on the field survey data. A multiple regression equation,
incorporating meteorological or hydrological information in each rainfall event, could produce more reliable
estimation results with not a large data required, and more data acquisition and analysis are ongoing.

Acknowledgement
The authors express their gratitude to the cooperating staffers of municipalities in the field survey for miscellanious supports.

References
Environmental Agency (EA) (1971) Notification of Environmental Quality Standards on Water Pollution. (amended in 1974,
1975, 1982, 1985, 1986, 1991, 1993, 1995, 1998, 1999, 2000, and 2003) (in Japanese)
Water Quality Management Division, Water Quality Conservation Bureau, Environmental Agency (EA) (1990) Manual for
Research of Nonpoint Pollution Load. March, 1990 (in Japanese)
Fujiu, K., Yoshida, T. and Tamoto, N. (2005) Research on urban nonpoint pollution control. FY2004 Annual Report of
Wastewater Management and Water Quality Control. July 2005 (in Japanese)
Fujiu, K., Yoshida, T. and Tamoto, N. (2006) Research on urban nonpoint pollution control. FY2005 Annual Report of
Wastewater Management and Water Quality Control. June 2006 (in Japanese)- 352 -

Japan Sewerage Works Association (JSWA) (1999) Guideline and Commentary on Comprehensive Basin-wide Planning of
Sewage Works (Version of 1999). October 1999 (in Japanese)
Water Quality Management Department, Ministry of Land, Infrastructure and Transport (MLIT) and Japan Institute of
Wastewater Engineering Technology (JIWET) (2002) Tentative Guideline on Urban Nonpoint Pollution Control.
March 2002 (in Japanese)
Environmental Risk Assessment Office, Ministry of the Environment (MOE) (2003) Environmental Risk Assessment on
Chemical Substances. March 2003 (in Japanese)
Nakamura, E. (1993) Loadings Characteristics of Stormwater Runoff. Journal of Japan Sewerage Works Association, Vol.30,
No.364, 1-13, 1993 (in Japanese)
Sakakibara, T., Masuta, T., Matsubara, M. and Kato, S. (2005) New Goals and Strategies for CSOs Control from Legal
Aspect. Proc. 10th International Conference on Urban Drainage, Copenhage/Denmark.
Tamoto, N. and Yoshida T. (2005) Research on Runoff characteristics of bis-phenol A and Benzo(a)piren. Proc. 33rd
Environmental System Conference, Sapporo. (in Japanese)
Tamoto, N., Yoshida, T. and Fujiu, K. (2005) Runoff characteristics of pollutants inclusive of heavy metals from urban areas.
Proc. 5th Environmental Technology Conference, Osaka. (in Japanese)
Tamoto, N., Yoshida, T. and Fujiu, K. (2007) Field Survey and Alternative Estimation on Runoff Pollution Load from Urban
Areas. Proc. Novatech 2007 (under contribution)- 353 -

- 354 -[Investigation on load reduction measures]“Load reduction in domestic and commercial wastewater is madeby sewerage construction, while other load reduction is made byeach source, and the control measures should be clarified”.
“--- in case urban areas are targets of load reduction, thereduction loads and the measures should be clarified. As control
measures of urban nonpoint pollution, there are “Plans of CSOs
National InstituteLand and Infrastructure
abatement,” and “Programofforsupporting
next generation
3
Management, Japansewerage projects (Type of nonpoint pollution control).”Comprehensive Basin-wide Plans for Sewage Works(CBPSW) in Japan perform as high-ranking schemes ofsewage works.
 Allowable pollution loads are allocated to each pollution
source in order to achieve environmental water quality
standards.
 “--- in case closed water areas are targeted, ---- allowablepollution loads are allocated also to nonpoint sources suchas urban areas and agricultural.”[CBPSW as hihg-ranking scheme][1] Current framework/status

National Institute for Land and Infrastructure Management (NILIM),
Ministry of Land, Infrastructure and Transport, Government of Japan

Yoshida, T. and Tamoto, N.

Present status and estimation methodof pollutant load in wet weather flowfrom urban areas

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

National Institute for Land and InfrastructureManagement, Japan(1) Generating loads including non-point
source on a watershed are estimatedusing unit pollution load data, andrunoff loads are calculated throughpollution analysis.
(2) The allowable load is calculated
based on the water quality standard
at a target point in the concernedwater body, and the pollution load thatshould be reduced (=reduction load)
is determined as a difference of thetotal generating load and theallowable load.
(3) The reduction load is distributed toeach pollution source category suchas public sewerage, industrial,
livestock, and non-point source (e.g.
urban, farm).

[Formulation of CBPSW]National Institute for Land and InfrastructureManagement, Japan

2

許容負荷量

4

点源 生活・営業
点源 工場
点源 家畜
面源 市街地系
面源 農地系面源 山林系

T流総-T沼(COD)

流達負荷量[3] Research on load estimation methods ofurban runoff[2] Field survey of urban runoff, focusing onconventional, heavy metals, and endocrine
disrupting chemicals[1] Review of the current framework/status ofurban nonpoint pollution control

Outline

負荷量(kg/日)

- 355 -57Type of Water Circulation Restoration(178)
Type of Nonpoint Pollution Control(3)Type of Recycled Resources Utilisation(163)
Type of Potential Energy Utilisation(7)
Type of New Technology Utilisation(30)
Type of Advanced IT(15)(Number of projects adopted from fiscal 1996 to 2005)

National Institute for Land and InfrastructureManagement, Japan

Water Environment
Creation Project
Recycle Promotion
Project
Function Upgrade
Promotion Project

National subsidy program to promote newly required
roles of sewage works, such as water environment
creation, recycle promotion, and coping with IT.
Type of nonpoint pollution control = Pollution load
reduction in initial rainfall runoff or gray water

Program of Supporting Next
Generation Sewerage Project[Financial assistance]

National Institute for Land and InfrastructureManagement, Japanbe necessarily allocated to the urban nonpoint
source pollution in an effectively manner.
 On the estimation process of generating loads ofurban non-point source, existing data in otherwatersheds are frequently applied instead ofcollecting data for a target watershed for thereasons of costs and the difficulty of performing
field surveys.

 In practice, allowable pollution loads could not[Issues of load allocation to urban areas]

National Institute for Land and InfrastructureManagement, Japan

Observe four rainfall events

Runoffcharacteristics
Different land uses
(Three drainage areas)

Runoff load

To clarify

Sampling atoutlets of the drainage areas

served by separate storm sewers

 Analyze runoff quality from urban areas[2] Field survey

National Institute for Land and InfrastructureManagement, Japan[Planning steps]
Investigate prioritisation of block areas.
Select areas to be controlled, and viable control measures.
Determine control measures and the scale(for cost-minimisation)[Issue]The Guideline could have been scarcely referenced inpractice.

"Tentative Guideline for Urban Nonpoint Pollution Control"
provides the knowledge of urban nonpoint pollution control
as well as the relevant planning and research methods.
The Guideline includes detailed description in accordance withhigher-ranking schemes such as CBPSW.

[Planning of urban nonpoint pollution control]

86

- 356 -Prior dry weather days (d)

0

30

60

90

Rainfall 2

Rainfall 3

Rainfall 4

40

30

20

9

TP

Bisphenol A

Zn

TN

11

14 to 20 samples / rainfall event

Total precipitation (mm)National Institute for Land and InfrastructureManagement, Japan

Drainage area A

Rainfall 1

Prior dry weatherdays (d)Total precipitation
(mm)

10

0

National Institute for Land and InfrastructureManagement, Japan

Observed rainfalls

120

Cd

CODMn

Benzo [a] pyrene

Pb

Cu

Heavy metals

Endocrine disrupting
chemicals

BOD

SS[Drainage are A]

13:00

0

200

17:00

19:00
Time

21:00

23:00

12

10

8

6

13:0015:0017:0019:0021:0023:00 1:00
Time
Precip itation
Flow

0

1

2

4

2

4
3

0

5

National Institute for Land and InfrastructureManagement, Japan

0

200

400

400

800

1000

600

15:00

SS
CODM n
Zn
600

800

1000

[Drainage area A]

10

Arterial road： Not
included

Arterial road：Included
National Institute for Land and InfrastructureManagement, Japan

Area： 67ha
Impervious area： 61%
Land use：Residential[Drainage C]

Area： 18ha
Impervious area： 67%
Land use：Residential[Drainage area B]

Result in Rainfall 3

Area： 95ha
Impervious area：69%
Land use：
High/medium rise
residential,
Commercial
Arterial road: IncludedSS(mg/l)Conventional

CODMn(mg/l), Zn(mg/l x100)

Study sites

Flow(m3/s)

Constituents analysed

Precipitation(mm/30min)

- 357 -SS(mg/l)

17:00

19:00
Time

21:00

10

0

tr

0

13

8

1

13:0015:0017:0019:0021:0023:00
Time
Precipitation
Flow

6

2

4

2

4
3

0

5
Precipitation(mm/30min)

CODMn(mg/l), Zn(mg/l x100)

SS

CODM n (mg/L)

Drainagearea A

CODMn

Drainagearea B

15

Drainagearea CR1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R4National Institute for Land and InfrastructureManagement, Japan

Drainagearea C

00

Drainagearea B

10

20

Drainagearea A

2040

R1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R4

30

60

50
40

SS (mg/L)

80

100

∫

Event mean concentration EMC = M = ∫0 ctr(t )q(t )dtVq (t )dt[SS, CODMn]

Flow(m3/s)

National Institute for Land and InfrastructureManagement, Japan

23:00

0

0

15:00

20

100

13:00

40

200

80

100

60

SS
CODM n
Zn

300

400

500

[Drainage area B]

15:00

23:00

0

20

40

60

80

100

0.4

TN

Flow

14

10

8

6

Drainagearea ATP

Drainagearea B

16

Drainagearea CR1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R4

TP (mg/L)

Precipitation

13:0015:0017:0019:0021:0023:00
Time

0

1

2

4

2

4
3

0

5

National Institute for Land and InfrastructureManagement, Japan

Drainagearea C

0.0

0

Drainagearea B

0.1

1

Drainagearea A

0.2

2

0.3

0.5

0.6

4
3

Flow(m3/s)

National Institute for Land and InfrastructureManagement, Japan

21:00

TN (mg/L)

19:00
Time

R1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R4

17:00

SS
CODM nCODMn(mg/l), Zn(mg/l x100)56[TN, TP]

13:00

0

200

400

600

800

1000

[Drainage area C]

Precipitation(mm/30min)

SS(mg/l)

0.04
0.03
0.02
0.01
0.00

0.4

0.3

0.2

0.1

0.0

Zn

Drainagearea B
Drainagearea A

National Institute for Land and InfrastructureManagement, Japan

Drainagearea C

L:
Σr :
NDD :
a, b :Pb (mg/L)

Pb

Drainagearea B

17

Drainagearea C

National Institute for Land and InfrastructureManagement, Japan

Specific load per rainfall event (kg/ha)
Total rainfall per event (mm)Number of prior dry weather day (day)Parameters
19

Pollutants to be conveyed
Æ Meteorological condition

L = a･Σr + b･NDD

Pollutants to be conveyed
Æ Meteorological condition

2.3

R1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R4[3] Load estimation method

Drainagearea AR1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R40.05

Zn (mg/L)

0.5

1.10

[Zn, Pb]
BPA (μg/L)

0.01
0.00

0.0

0.32

Rainfall 4

0.14

Rainfall 1

0.27

4.44

Rainfall 4

2.21

22.95

Rainfall 3

Rainfall 3

2.25

Rainfall 2

Rainfall 2

3.83

Rainfall 1

0.071

0.372

0.103

0.040

0.852

7.478

0.767

0.908

(kg/ha)

CODMn

TN

0.019

0.051

0.012

0.009

0.145

0.763

0.104

0.172

(kg/ha)TP

0.00080.00610.00080.00050.01560.08450.01350.0174(kg/ha)National Institute for Land and InfrastructureManagement, Japan

0.035

0.226

0.063

0.020

0.382

3.566

0.519

0.751

BOD
(kg/ha)SS

Drainagearea B

Zn

0.7

0.7

0.4

17.8

349.2

9.1

4.4

(g/ha)

Σr

12

63

10

7

3

63

10

7

(mm)

20

13.5

34.0

8.0

14.5

16.5

37.5

6.0

14.0

(day)

NDD

18

Drainagearea C

Benzo [a] pyrene

Drainagearea A

Data of regression analysis(kg/ha)B(a)P (μg/L)

R1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R4National Institute for Land and InfrastructureManagement, Japan

Bisphenol A

Drainagearea C

0.02

0.2

Drainagearea B

0.03

0.4

Drainagearea A

0.04

0.05

0.6

R1 R2 R3 R4 R1 R2 R3 R1 R2 R3 R4

11.0

0.8

1.0

[B(a)P, BPA]

Drainagearea A
Drainagearea C- 358 -

-0.01200.0414a (kg/ha/mm)

b (kg/ha/day)

0

0.02

0.04

0.06

0.08

0.1

0

0.5

1

1.5

2

2.5

3

0

0

1

1.5

2

2.5

0.02 0.04 0.06 0.08
M easured TN (kg/ha)

M easured SS (kg/ha)

0.5

0.1

3

(Drainage area C)

Drainage
areaC

0.046

0.243

0.00570.0005

0.106

0.025

CODMn

0

0

0.2

0.3

0.4

0.5

0.002 0.004 0.006 0.008 0.01
M easured TP (kg/ha)

M easured CODM n (kg/ha)

0.1

National Institute for Land and InfrastructureManagement, Japan

0

0.002

0.004

0.006

0.008

0.01

0

0.1

0.2

0.3

0.4

0.5

National Institute for Land and InfrastructureManagement, Japan

0.0038-0.0003

0.021

BOD

0.211

SS

0

0.05

0.1

0.15

0.2

0.25

0.3

0

0.000480.00065

0.00770.0077

TN

21

-

-

0.0062-0.0010Zn

M easured BOD (kg/ha)

23

0.05 0.1 0.15 0.2 0.25 0.3

0.00011-0.00003-0.00500.0174

TP

1

0

0

1

1.5

2

2.5

0.4

0.6

0.8

M easured TN (kg/ha)

0.2

M easured SS (kg/ha)

0.5

1

3

0

0

1

2

3

4

0.4

0.6

0.8

M easured TP (kg/ha)

0.2

M easured BOD (kg/ha)

15

National Institute for Land and InfrastructureManagement, Japan

0

0.2

0.4

0.6

0.8

1

0

1

2

3

4

5

0

0.1

0.2

0.3

0.4

0.5

0

2

4

6

8

10

0

0

Method

4

6

8

0.2

0.3

0.4

0.5

L =a ･∑r ＋b ･NDD-

∑L =(1/A )･∑(D i･L i･A i)∑L =k ･C ･∑R

Equation

M easured Zn (kg/ha)

0.1

10

22

∑L: Unit load (kg/ha/year)
k: Runoff percentage
C: Annual average concentration (kg/ha/mm)∑R: Annual precipitation (mm/year)
A: Catchment area (ha)Di: Runoff coefficient for land use "i" for pollution at the concerning point
Li: Pollution load from land use "i“
Ai: Area of land use "i" in catchment area (ha)
L: Pollution load per a rainfall event(kg/ha)∑r:
precipitation (mm)National
Institute for Landand EventInfrastructure
24Management,
Japan Number of prior dry weather days (day)a, b: Coefficients in multiple regression equation
NDD:

Summation of pollution loads per rainfall event,(4) which are calculated with multiple regression
equation

Summation of pollution loads per rainfall event,(3) which are calculated with correlation equation
between event precipitation and runoff load

Product of annual average concentration,
annual precipitation, and runoff percentage
Summation of pollution loads from each land(2)
use area
(1)

No.

2

M easured CODM n (kg/ha)

Principal estimation methods

0

0.2

0.4

0.6

0

0.5

1

1.5

2

2.5

0.8

Estimated SS (kg/ha)

Estimated TN (kg/ha)

3

Estimated TP (kg/ha)(Drainage area A)
Estimated BOD (kg/ha)

Comparison estimated/measured
Estimated CODMn (kg/ha)

Estimated Zn (kg/ha)

Result of regression

Estimated BOD (kg/ha)

Drainagre a (kg/ha/mm)
area Ab (kg/ha/day)

Estimated SS (kg/ha)

Estimated TN (kg/ha)

Estimated CODMn (kg/ha)

Estimated TP (kg/ha)- 359 -

- 360 -25

Field survey revealed concentration in time series varied byorder of magnitude, corresponding to the rainfall runoff flow,
and runoff quality characteristics varied among drainage areas.
EMCs of almost all analysed constituents exceeded EQSs or
PNECs, and they could have not an ignorable effect onreceiving waters.



National Institute for Land and InfrastructureManagement, JapanThe Japanese current framework/status of urban nonpoint
pollution control was reviewed.
The control has not yet been vigorously addressed though
there are a planning framework, a technical guidance, and afinancial programme.
Further knowledge and technical improvement should besought to better planning and the related researches.

ConclusionNational Institute for Land and InfrastructureManagement, Japan26

A load estimation method was researched based on the fieldsurvey data.
A multiple regression equation, incorporating meteorologicalor hydrological information in each rainfall event, could
produce more reliable estimation results with not a large datarequired.
More data acquisition and analysis are ongoing.

Cont.

Development of Wet-Weather Sewage Treatment Technologies and their
Application to the Combined Sewer System Improvement Plan of Osaka
City
Enao Takayanagi*, Makoto Fujita**Environment and Sewerage Bureau, Osaka City Government, 1-14-16 Nanko-kita, Suminoe-ku,
Osaka 559-0034 Japan
Abstract: In Osaka City, since 97% of the city area is served by combined sewer systems (CSS),
the Osaka City Government has been originally carried out researches and experiments on CSS
improvement methods, particularly wet weather combined sewage treatment technologies.
Among them, ³wet weather sewage activated sludge process´ and ³sedimentation using inclined
plate settlers with coagulant addition´ have been successfully developed to a practical level, which
can effectively increase continuous wet weather sewage treatment capacity of existing sewage
treatment facilities with relatively lower cost and shorter period. The city government has revised
its CSS improvement plan by applying these technologies, with the objective of reducing discharge
pollutant loads in effluent and overflow from the CSS during wet weather to the equivalent level ofseparate sewer system. This paper presents the performance of the above newly developed
technologies and the basic concept of the CSS improvement plan.
Key words: combined sewer system, plate settler sedimentation, wet-weather activated sludge
process

Introduction
Osaka is the largest city in western Japan witha resident population of about 2.63 million (daytime
population of about 3.66 million) and area of about
220 km2. Most of the city area lies below the riverflood level, and gravity drainage area is only about
10% of the city area. Therefore, most of thestormwater needs to be collected once at sewage
treatment plants or pumping stations then pumped
and discharged to public water bodies.
In the modern sewerage construction projects
in Osaka City started in 1894 in response to cholera
epidemics, CSS was adopted in order to improve
public hygiene and control flooding at lower cost andin a shorter period. Currently, the sewer systemcovers almost 100% of the city area, and 97% of thesewered area are served by CSSs (Figure 1).
- 361 1-

Fig. 1: Areas Served by Combined Sewer Systems

In CSSs, when sewage flow exceeds a certain level during wet weather, untreated sewage
may be discharged directly from combined sewer overflow (CSO) outfalls and pumping stations topublic water bodies. A survey conducted by the City Government revealed that, among thepollutant loads flowing into sewage treatment plants, the proportion discharged to public water
bodies was 14% in terms of BOD and 36% in terms of SS. Out of this pollutant load discharged to
public water bodies, 70% of BOD and 80% of SS are discharged during wet weather conditions.
This result shows that it is the key issue to reduce the pollutant load in wet-weather discharges forthe further improvement of the quality of public water bodies.
Since the 1970s, when the coverage of the sewer system increased and the safety against
floods was improved to a certain level in the city, the City Government has been carried out
researches and studies on technologies for CSS improvement. Especially, in Osaka City, almost
the entire city area has been already urbanized, therefore, it is very difficult to acquire lands for theconstruction of new treatment facilities. Furthermore, the cost for CSS improvement has to beminimized as possible because the scale of CSSs in Osaka is so huge. From these points of view,
the City Government has been actively developed and introduced original technologies to increase
continuous wet-weather sewage treatment capacities by fully utilizing existing facilities, instead ofother CSS improvement methods commonly adopted in Japan such as construction of wet-weather
sewage storage facilities and sewer separation.
This paper introduces the major technologies for CSS improvement newly developed by the
Osaka City Government and the city¶s CSS improvement basic plan applying these technologies.

Wet-Weather Sewage Treatment Technologies for CSS Improvement
Developed by the Osaka City Government
Wet-weather sewage activated sludge process
In Osaka City, sewage treatment plants are designed to receive up to three times of the design
peak dry weather flow (3Qsh) in wet weather conditions. In the conventional method, 1Qshamong 3Qsh was treated by the activated sludge process and the remaining 2Qsh was treated byonly primary sedimentation and discharged (Figure 2). In the wet-weather activated sludge
process, this 2Qsh of wet-weather sewage is fed into the latter section of aeration tanks and istreated by the activated sludge process (Figure 3).
Activatedsludgetreatment(1Qsh)

Wet
weatherwastewater(3Qsh)
1Qsh
Primary
sedimentationtank

Discharge after
sedimentation(2Qsh)

Aeration tankFinal
sedimentation
tank

Wet
weatherwastewater(3Qsh)
Primary
sedimentationtank

Discharge after
sedimentation(2Qsh)

Return sludge

Fig. 2: Conventional Wastewater Treatment during Wet Weather- 362 2-

2Qsh
1Qsh

Aeration tank

Activatedsludgetreatment(3Qsh)
Final
sedimentation
tank

Return sludge

Fig. 3: Wet Weather Activated Sludge Process

With the conventional activated sludge process, pollutants are absorbed by activated sludge inthe first 30 minutes or so, and then gradually decomposed. In the wet-weather activated sludge
process, the hydraulic retention time of wet-weather sewage fed into the latter section of aeration
tanks is about 30 minutes, and pollutants in the wet-weather sewage are quickly removed due to theabsorption by the activated sludge suspended in the aeration tanks.
Furthermore, the aeration tanks in sewage treatment plants in Osaka City have been equippedwith channels for step feeding to be applicable for both the conventional activated sludge process
and the step feed aeration process. Thus, this new process could be introduced with relatively
small modifications of existing facilities.
The Osaka City Government started design studies on this treatment process in 1988, andcarried out performance surveys at treatment facilities using this process from 1992 to 2002. The
results verified stable operations while processing sewage volume ranging from 1.48 to 4.62 Qsh(2.70 Qsh on average) with the average effluent quality at 9.3 mg/L in SS and 7.7 mg/L in BOD.
In addition, results from four surveys verified that this new method could reduce the amount ofpollutant discharge by 59 to 91% (73% on average) in SS, and by 27 to 78% (61% on average) in
BOD for a single rainfall event, when compared with the conventional method employing primary
sedimentation (Figure 4).
In September 2000, when there was a prolonged rain event with the total rainfall of 165 mm,
this process was continuously operated for 45 hours stably, and it was verified that the new process
was capable of prolonged continuous operation.
Since these results have demonstrated the effectiveness of the wet-weather activated sludge
process, the Osaka City Government has been introducing this process to all 12 sewage treatment
plants by March 2007.
Comparison of discharge pollutant load in SS

Comparison of discharge pollutant load in BOD
100

80

60

40

by 73%

84%

80

Reduction

60

Primary treatment
Activated sludge
treatment

40

20

27%

20

Wet weather
activated sludge
process

078%

by 61%

Primary treatment
Activated sludge
treatment

Reduction

100

39%
16%
0

Conventional
treatment

22%
Conventional
treatment

Wet weather
activated sludge
processFig. 4: Effect of the Wet Weather Activated Sludge Process- 363 3-

Sedimentation process using inclined plate settlers with coagulant addition
Sedimentation process using inclined plate settlers is adopted in the treatment of drinking
water supplies. The Osaka City Government has carried out studies on this process for treating
wet-weather sewage, which tends to increase rapidly, within limited land area. From the late1970s, the City Government carried out monitoring on the characteristics of wet-weather sewage
and experiments on the plate settler sedimentation process, and obtained the following results:
1) Wet-weather sewage contains high content of suspended solid (SS) with a high sedimentation
velocity, therefore, it is reasonable to use this process to separate this high settleable SS component.
2) At an average flow rate of 0.5 to 0.6 m/min. in the plate settler module with the detention time ofabout 10 minutes, effluent quality is equivalent to the one from a conventional sedementation tank.
Besides, experiments were carried out to investigate the effect of coagulant dose to
sedimentation efficiency and resulted in the following:3) Poly-aluminum chloride (PAC) is most suitable as a coagulant for the wet-weather sewage
sedimentation process.
4) By adding PAC at the concentration of 2.5 to 10 mg-Al/L, influent sewage with BOD of 100 to
200 mg/L can be treated to produce an effluent with BOD of 20 to 25 mg/L with the detention time
not exceeding 10 minutes.
However, as mentioned earlier, it is very difficult to acquire lands in Osaka City for theconstruction of new treatment facilities, therefore, the City Government started design studies on
modifying existing primary sedimentation tanks to plate settler sedimentation tanks as an alternativeengineering option, and installed inclined plate settler modules to an existing primary sedimentation
tank in the Osaka City¶s Chishima Sewage Treatment Plant as a pilot treatment facility for thisprocess. The performance surveys were carried out for 29 rainfall events for one-year period from
October 2004. The specifications of the experimental facility are as follows:- Inclined plate settler type: Horizontal flow, flat plate type
- Length of inclined plates: 3 to 6 m- Angle of inclination:
60º- Height of a settler module: 2.5 m- Intervals of inclined plates: 100 mm- Inclined plate material:
Vinyl chloride resin and recycled plywood- Coagulant:
PAC- Rapid Mixing:
Utilize pre-aeration- Flocculation:
No special equipment/device is provided- Inclined plate cleaning:
Air blowing and water spraying- Sludge collector:
N/A- Sludge removal:
Discharge sludge by water flushing after rainfall events
In order to effectively utilize the existing sedimentation tank, it is necessary to place multiple
inclined plate settler modules in the tank and distribute the influent sewage to each module.
Therefore, influent main pipes are placed in the tank and connected with perforated pipes at theirend as shown in Figure 5.
- 364 4-

Fig.5

Design of Inclined Plate Settler in Chisima Sewage

ᵹ౉

Inflow Conduit TubeǾ600

Inclined Plate Unit

Inflow Multi-hole DuctǾ2505Inflow Multi-hole DuctǾ3005Plan View of Inflow Conduit
OutflowConduit TubeǾ600

OutflowConduit TubeǾ500

OutflowConduit TubeǾ600

Outflow

Outflow Multi-hole DuctǾ2005Outflow Multi-hole DuctǾ3006OutflowMulti-hole DuctǾ2004

Plan View of Inflow Conduit
OutflowConduit Tube
Inflow Multi-hole Duct

Inflow Conduit Tube

Outflow Multi-hole Duct

Stectional View

The hole size of perforated pipes must be determined to distribute influent sewage to theindividual modules equally. Perforated pipes are vertically placed near the inlet cross-section ofplate settler modules to distribute the influent sewage evenly in horizontal and vertical directions of
the module cross-section and mitigate density currents.
For the inclined plates, vinyl chloride resin plates and recycled plywood plates (made fromwaste paper and plastic) are used. In the survey, treatment performance was measured under
different surface loading rates by changing the length of the inclined plates.
Sludge collectors were not installed, therefore, sludge is stored on the bottom of tank during
rainfall events. Then after rainfall events, water in the tank is once drained together with most of
the stored sludge, and the remaining sludge is flushed from the rear end of the tank using settled
water from the adjacent primary sedimentation tank.

Influent SS(mg/L)

Effluent SS (mg/L)

140
120

50
150
250
350
450
550

100
80
60
40
20
0
0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Flow Rate (m/min)Fig.6 Influence of Flow Rate to Effluent SS

Influent
BOD(mg/L)

140

Effluent BOD (mg/L)

Influence of flow rate in the plate settler
modulesFigures 6 and 7 show the relationship between theflow rate in the plate settler modules and the effluent
quality when the surface loading rate is less than 35
m3/(m2·d). SS concentration in the treated effluent
increased when the flow rate exceeded 0.5 m/min. andthe BOD concentration increased when the flow rate
exceeded about 0.55 m/min. It is observed that the
impact of the flow rate is less evident in BOD than in SS.
This may be attributed to the soluble BOD. From theseresults, it is considered that the flow rate in the plate
settler modules should be set 0.5 m/min or less.

120

50
150
250
350
450

100
80
60
40
20
0
0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Flow Rate (m/min䋩

Fig.7 Influence of Flow Rate to Effluent BOD- 365 5-

Influence of surface loading rate
Figure 8 shows the relationship between thesurface loading rate and the treated effluent quality
when the flow rate is below 0.5 m/min. As shownin the graph, it is observed that the effluent with
sufficient quality is obtained stably when the surface
loading rate is 40 m3/(m2·d) or less.

Influent SS(mg/L)

Effluent SS (mg/L)

60
50

50
150
250
350
450
550

40
30
20
10
0
0

10

20

30

40

50

Surface Loading Rate (m3/(m2·day))Fig.8 Influence of Surface Loading Rate to Effluent SS

Treated effluent quality
Based on the above observations, the relationship between the influent sewage quality and thetreated effluent quality was analyzed under the conditions when the flow rate is less than 0.5 m/min.
and the surface loading rate is less than 35 m3/(m2·d). The results are shown in Figures 9 and 10.
The SS values were averaged within each 100 mg/L range; and the BOD values were averaged
within each 50 mg/L range. The vertical bars show the standard deviation. It is considered thatpollutants can be removed to the level of the average effluent quality approximately at 20 mg/L in
SS and 20 to 30 mg/L in BOD, except when the pollutant concentration of the influent sewage is

45
40
35
30
25
20
15
10
5
0

60

Effluent BOD (mg/L)

Effluent SS (mg/L)

extremely high. Since little data was available under the condition of the influent sewage withhigh pollutant concentrations, such data need to be collected furthermore.
50
40
30
20
10
0
0

100

200
300
400
Influent SS (mg/L)

500

600

Fig.9 Average Influent and Effluent SS

0

50

100

150
200
250
Influent BOD (mg/L)

300

350

Fig.10 Average Influent and Effluent BOD

Removal rate
Under the same conditions, the relationship between the influent sewage quality and the

100
90
80
70
60
50
40
30
20
10
0

BOD Removal Rate (%)

SS Removal Rate (%)

removal rate is shown in Figures 11 and 12. The removal rate is approximately around 90% in SS
and 80% in BOD, although it shows low value when the pollutant concentration of the influent is at
low level.
100
80
60
40
20
0

0

100

200
300
400
Influent SS (mg/L)

500

0

600

50

100
150
200
250
Influent BOD (mg/L)

300

Fig.12 Average BOD Removal Rate

Fig.11 Average SS Removal Rate
- 366 6-350

From these findings based on the survey results, it is estimated that existing primary
sedimentation tanks can be capable of treating wet-weather sewage flow equivalent to five times its
present design maximum daily dry-weather flow by installing inclined plate settler modules withinclined plate intervals of 100 mm, flow rate in the plate settler module of less than 0.5 m/min., andsurface loading rate of 25 m3/(m2·d).
Furthermore, the city government is conducting performance surveys when applying this plate
settler sedimentation process to the primary sedimentation process under dry weather conditions.
It is expected that the plate settler sedimentation process will be able to have the equivalenttreatment capacity of the existing primary sedimentation tank with 1/2 to 1/3 of its original surface
area. In this case, the remaining space can be used for wet-weather sewage treatment by the plate
settler sedimentation process with coagulant addition. Then, the wet-weather sewage treatment
capacity can be increased without constructing new tank facilities.

The Newly Revised CSS Improvement Plan of Osaka City
In the previous CSS improvement plan of Osaka City, the objective was set as ³to reduce theannual discharge pollutant load including dry weather period to the equivalent level of separated
sewer system´, and various programs have been implemented such as eliminating sediment traps at
the bottom of manholes, introducing the wet-weather sewage activated sludge process, andconstructing stormwater reservoirs for storage of wet-weather sewage. However, in 2004, theSewerage Law Enforcement Order was amended and the wet weather effluent quality standard for
CSSs was newly stipulated. On the other hand, the city government has been originally studied
the plate settler sedimentation process as a CSS improvement method and developed to a practicallevel. In response to these changes and new developments, the Osaka City Government
established a new CSS improvement plan in March 2006.
Objectives
Mid-term objectives (target year: 2018)- Within each treatment area, the annual discharge pollutant load including dry weather periods
should be reduced to the equivalent level of separated sewer system. Here, it is assumed that the
average quality of wet weather discharge from a separated sewer system is 18 mg/L in BOD.
- The wet weather effluent quality should meet the standard stipulated in the Sewerage Law
Enforcement Order amended in 2004, that is the average quality of wet weather effluent during asingle rainfall event with the total rainfall of 10 to 30 mm should be not more than 40 mg/L in BOD
in each treatment area
- The number of overflow events from CSO outfalls should be reduced by half.
Long-term objective- The wet weather effluent quality should be the same level of dry weather effluent quality.
Specifically, the annual average effluent quality from each outlet should be not more than 15 mg/L
in BOD.

- 367 7-

Major approaches
In order to reduce discharge pollutant load to public water bodies, increasing wet weather
sewage treatment capacity was selected as the basic strategy, and the above objectives should beachieved mainly by the combination of following four major approaches.
1) Introduction of the wet weather sewage activated sludge process
2) Introduction of the plate settler sedimentation process with coagulant addition
3) Storage of wet-weather sewage utilizing large stormwater sewers designed for flood control
4) Newly construction of facilities for storage of wet-weather sewage such as stormwater reservoirs
In the implementation of the CSS improvement program, priority should be given to projects
concerning those public water areas that are important in terms of water quality protection andlandscape conservation.
Modification of primary sedimentation tanks
There are two necessary steps when the plate settler sedimentation process for wet weather
sewage treatment is introduced in the existing sewage treatment plants. First, the required area forprimary sedimentation of dry weather flow should be reduced to 1/2 to 1/3 by modifying existing
sedimentation tanks to the plate settler sedimentation process (without coagulant addition) or thehigh rate filtration process. Then, the plate settler sedimentation process with coagulant addition
should be introduced using the remaining 1/2 to 2/3 of the area for wet weather sewage treatment.
Cost and Benefit
Simulation analysis was conducted for one treatment area in the case of wet weather sewage
treatment up to 6Qsh by introducing the wet weather activated sludge process and the plate settler
sedimentation process with coagulant addition modifying existing facilities. The result shows thatthe following effects can be obtained.
1) 84% of wet weather sewage flows and 94% of the pollutant loads in the sewage can be captured
for treatment, and 83% of captured pollutant loads can be removed.
2) The annual discharge pollutant loads can be reduced to the equivalent level of a separate sewer
system.

79.2 72.1 84.0

96.7 91.8 94.2

Direct Discharge
81.7 83.4 83.1

Approach"C"

Approach"B"

Approach"A"

Approach"C"

Approach"B"

Approach"A"

Approach"C"

Approach"B"

Captured
Pollutant Loads
Captured Sewage
flows

35

1083

30
25

Construction Costs(billion JPY )Reccurent Costs(million JPY/year)

1200
1000
800

20
15
10
5

600

30.7

400

263
210
7.3

0

Reccurent Costs(million JPY/year)

Pollutant Removal
Rate

Approach"A"

100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%

Construction Costs (billion JPY)

3) Comparing the conventional CSS improvement approach of constructing stormwater reservoirs,
the construction costs and the annual recurrent costs can be reduce to about 20% for removing theequivalent amount of pollutant load.

200
6.3

0
Approach"A" Approach"B" Approach"C"
Fig 14: Construction Costs and Annual Recurrent Cost

Fig 13: Comparison of effect in alternative approaches

Approach ³A´: Stormwater reservoir (13mm) + sedimentation (2Qsh)Approach ³B´: Wet-weather activated sludge process (3Qsh) + Stormwater reservoir (3mm)Approach ³C´: Wet-weather activated sludge process (3Qsh) + Plate settler sedimentation with coagulant addition (3Qsh)- 368 8-

Exceeding 3Qsh (Direct discharge)

2Qsh

Final
SedimentationTanks

Influent flow

Temporarystorage

Reaction
Tanks(for
1Qsh)㩷

⚳ೋᴉ෻Primary
SedimentationTanks(for3Qsh)㩷

1Qsh㩷

Temporary Direct
storage discharge(bystormwater
Sedimentaion
reservoirs)
only

2Qsh

Secondary treatment

1Qsh

3Qsh

Time

Stormwater
Reservoirs(newly constructed)㩷

Fig 15: Image of Conventional Treatment Process in Wet Weather Events

Exceeding 6Qsh (Direct discharge)

Reduction in direct discharge
Increase in WWF
treatment capacity

Install additional treatment
devices for remaining area

3Qsh
Temporary
Storage
Stormwater Sewers
Storage Facilities

Final
Sedimentation
Tanks

1Qsh
3Qsh

Influent flow

ೋ
ᴉ

Wet
Weather
Activated
SludgeProcess
(for
3Qsh)

⚳

Plate
Settler
SedimentationPrimary
sedimentation

෻

3Qsh

3Qsh
Temporary Direct
storage discharge
Plate settler
sedimentation
with coagulant
addition
Wet weather
activated◲ᤃ᡼
sludge process 㩷

Reduction in the area for primary sedimentation
by high rate filtration or plate settler
sedimentation without coagulant addition

Fig 16: Image of Wet Weather Sewage Treatment in the New CSS Improvement Plan

- 369 9-

3Qsh

2Qsh
1Qsh
Time

Table 1: Estimated Project Cost for CSS Improvement
Furthermore, the total project
Approaches
Cost (billion JPY)
costs for the previous improvement
Wet Weather Activated Sludge Process
18
Plate Settler Sedimentation Process57
plan was estimated to be about 300
Construction of Storage Facilities
87
billion yen. However, based on the
Other Approaches
Filling Sediment Traps in Manhole Bottoms
30
above results, the total project costs toReplacement of Screens, etc.
achieve the mid-term objectives for the
Total
192
entire city area was estimated to beabout 200 billion yen as shown in Table 1, a saving of about 100 billion yen.

Future issues- In order to significantly increase the amount of sewage processed at sewage treatment plants,
further studies are required regarding transfer of sewage to treatment plants, distribution of sewage
to various treatment processes in each plant, capacity of effluent channels, etc.
- For actual operations of storing wet weather sewage utilizing large stormwater sewers,
technologies such as real-time control need to be studied to ensure CSO control and flood control
without lowing safety level against floods.

Conclusions
The Osaka City Government has selected CSS to achieve the flood control and public hygiene
improvement at the same time. Thereby, the sewer systems were constructed rapidly over theentire city area. CSSs were able to cope with increase in wastewater flow due to urban density
growth. Currently in Japan, the problem of wet weather discharge pollutant load by CSOs is oneof the priority issues for water environment protection. The Osaka City Government is now
planning to take comprehensive countermeasures by combining various methods including someoriginally developed technologies, and expects to be able to eventually capture and treat almost allof wet-weather sewage except in the case of extremely heavy rains comparable to the probablemaximum precipitation. If such improvements are achieved, CSS has the potential to become an
excellent system that can also deal with non-point source pollutants released in wet weather
conditions.
The City Government will continuously monitor CSOs at main overflow outlets in order toadequately investigate CSO characteristics and clearly identify the benefits and costs of various
program components for implementing the improvement plan with public consensus.

References
Takayanagi E., Horita K., Fukui S., Taruya T. and Yamamoto S. (1997): Measures against
Combined Sewer Overflow in Osaka City, Proceedings the 7th Japanese-German Workshop on
Wastewater and Sludge Treatment, pp.8-3-1-11, 1997
Takayanagi E., Abe T, Taruya T and Fukui S. (1997): Introduction of Plate Settler for Combined
Sewer Overflow Treatment, Water Science and Technology, Vol. 36, No. 8-9, pp.207-212, 1997,
IAWQ- 370 10-

- 371 

1

3/40

Resident population:
2.63 million
 Daytime population:
3.66 million
2
 Area: 220 km
 Sewers: 4,830 km
 Pumping Stations: 57
 Sewage Treatment Plants(STPs):12
 Total Treatment Capacity:
2,844,000 m3/day

Profile of Osaka City

Manager for Project Assessment and Evaluation
Administrative Division
Environment and Sewerage Bureau
Osaka City Government

Makoto Fujita

Development of Wet Weather Sewage
Treatment Technologies and their
Application to the Combined Sewer
System Improvement Plan of Osaka City

Geographical Feature

4/40

2/40

Combined sewer systems (CSSs) improvement
plan of Osaka City, which was recently revised
applying the above technologies.

Wet weather sewage activated sludge process
Plate settler sedimentation process with coagulant
addition

Most of the city area lies
below the river flood level.
 Gravity drainage area isonly about 10% of the cityarea.
 Therefore, most of thestormwater need to becollected once at STPs or
pumping stations, thenpumped and discharged
to public water bodies.








Profile and features of Osaka City and its
sewerage system Wet weather sewage treatment technologies
developed by Osaka City Government to apractical levelPresentation Topics

- 372 -





5/40

7/40

From the these points of view, the City
Government has been actively developedand introduced original technologies toincrease continuous wet weather sewage
treatment capacities by fully utilizing
existing facilities, instead of other CSS
improvement methods commonly
adopted in Japan, such as construction ofstormwater reservoirs and sewer
separation.

Selected Alternatives for CSS
Improvement in Osaka City

In the modern sewerage
construction projects
stared in 1894, combined
sewer system (CSS) was
adopted for publichygiene improvement andflood control at the sametime with lower cost andin a shorter period.
 Currently, the sewer
system covers almost
100% of the city area,and 97% is served by
CSSs.

Sewage Collection System

Hirano STP

Ono STP

6/40

Imafuku STP

1980s Experimental studies, 1988 Design studies,1990 Pilot plant studies,1998 Introduction to full scale treatment facilities started
Late 1970s Experimental studies, 1987 Design studies, 2002
Experiments on coagulant addition, 2004 Pilot plant studies
1980s Experimental studies, 1987 Design studies,1998 Installation of a full scale unit
1983 Research studies, 2000 Operation started

1984 Effectiveness surveys in pilot areas, 1995 Modifications
started for the entire city area, 2003 Completion
2003 Pilot plant studies

Wet Weather Sewage
Activated Sludge
Process
Inclined Plate Setter
Sedimentation Process
Fine Mesh Screens for
Wet Weather Sewage
Storage of Wet Weather
Sewage utilizing
Stormwater Sewers
Filling Sediment Traps at
the Bottom of Manholes
Wet weather sewage
high rate filtration

8/40

1971 Design, 1974 Performance survey

Wet Weather Sewage
Sedimentation Tank

R&D on CSO Control Technologies
carried out by Osaka City Government

Tsumori STP

Almost the entire city area has been alreadyurbanized, therefore, it is very difficult toacquire lands for the construction of new
facilities.
 Because the scale of CSSs in is so huge,
the cost for CSS improvement has to beminimized as possible.
Constraints in CSS Improvementin Osaka CityIn the “wet weather
activated sludge
process”, 2Qsh is fed
Wet
2Qsh
into the latter section of weather
wastewater
aeration tanks and(3Qsh)
1Qsh
treated by the activatedPrimary
sedimensludge process.
tationAeration tanktank
 The results of 27
surveys verified stable
Discharge after
operations in processing
sedimentation
Return sludge
sewage volume of 1.48(2Qsh)
4.62 Qsh with theaverage effluent quality
at 9.3 mg/L in SS and7.7 mg/L in BOD.



9

11/40

Final
sedimentation
tank

Activatedsludgetreatment(3Qsh)

Wet Weather Sewage ActivatedSludge Process

Wet Weather Sewage
Activated Sludge Process

Return sludge

Aeration tank

1Qsh

Pollutant Removal in the
Activated Sludge Process
In the conventional
activated sludge process,pollutants are absorbedby activated sludge in thefirst 30 minutes andgradually decomposed.
 In the wet weather
activated sludge process,the hydraulic retention
time of 2Qsh wet weather
sewage fed into the latter
section is about 30 min,therefore, pollutants inthe sewage are quickly
removed.


In Osaka City, STPs aredesigned to receive up to
3 times of the designWetweatherpeak dry weather flow
wastewater(3Qsh).
(3Qsh)
 In the conventional
Primary
sedimenmethod, 1Qsh wastationtanktreated by the activatedsludge process, and theDischarge after
sedimentation
remaining 2Qsh was(2Qsh)
treated by only primary
sedimentation anddischarge.

Absorption Decomposition(approx. 30 min)

12/40

Time

10/40

Final
sedimentation
tank

Activatedsludgetreatment(1Qsh)

Conventional Sewage Treatment
during Wet Weather

Concentration- 373 -

SS, BOD (mg/L)

0

30

60



After (automatically
13/40

4:00

9:00

14:00

19:00

0:00

5:00
Time

10:00

15:00

20:00

1:00

Treated Wet Weather Sewage Flow
Influent SS (mg/L)
Influent BOD (mg/L)
Effluent SS (mg/L)
Effluent BOD (mg/L)

15/40

0

1

2

3

4

5

In September 2000, when there was a prolonged rain
event with the total rainfall of 165 mm, this process wascontinuously operated for 45 hours stably, and it wasverified that the new process was capable of prolonged
continuous operations.

Result of Prolonged Continuous
Operation (45 hours)

Before (hand

treatment

Conventional

16%

84%

Wet weather
activated sludge
process

27%

0

20

40

60

80

treatment

Conventional

22%

78%

Activated sludge
treatment

Primary treatment

Comparison of discharge pollutant load in BOD
100

Wet weather
activated sludge
process

39%

14/40

23:00

4:00

0
18:00

0

2

3

4

5

1
13:00

Treated Wet Weather Sewage Flow
Influent SS (mg/L)
Influent BOD (mg/L)
Effluent SS (mg/L)
Effluent BOD (mg/L)

50

100

150

200

16/40

In January 2001, when the influent pollutant load washigh for a long time (the highest BOD was 160 mg/L,
the average BOD was 120 mg/L), it was verified thisprocess was capable of operations under high pollutant
loading condition.

Operation under High Pollutant
Loading Condition

0

20

40

60

Activated sludge
treatment

Primary treatment

by 73%

80
Reduction

100

Comparison of discharge pollutant load in SS

Results from 4 surveys verified that this new process
could reduce the amount of pollutant discharge by 5991% (73% on average) in SS, and by 27-78% (61% on
average) in BOD for a single rainfall event, comparedwith the conventional wet weather sewage treatment.

by 61%

The aeration tanks in STPs in Osaka City have beenequipped with channels for step feeding to be
applicable for both the conventional activated sludge
process and the step feed aeration process.
 Thus, this new process could be introduced withrelatively small modifications of existing facilities.

SS, BOD (mg/L)

Reduction

Advantages

Ratio of treated sewage flow rate to
Design dry weather peak flow（Qsh）

Effect of Wet Weather ActivatedSludge Process

Ratio of treated sewage flow rate to
Design dry weather peak flow （Qsh）- 374 -

- 375 -Sedimentation Process using
Inclined Plate Settlers

Inclined
Plate Settler
ModulePlate settler sedimentation process is adopted in thetreatment of drinking water supplies.
 Osaka City Government has carried out studies andexperiments on the application of this process fortreating wet weather sewage since the late 1970s.





19/40

17/40

From the results of performance surveys, it was verified; The operation of this process can run stably, while
treating up to 3 times of the design peak dry weather
flow .
 This process is capable of prolonged continuous
operations and under high pollutant loading condition.
 The amount of pollutant discharge can be considerably
reduced, compared with the conventional method.
 Since these results have demonstrated the effectivenessof the “wet weather activated sludge process”, Osaka City
Government has been introducing this process to all 12
STPs by March 2007.

Summary - Wet Weather ActivatedSludge Process

Wet weather sewage contains high content of
SS with a high settling velocity, therefore, it isappropriate to use this process to separate thehigh settleable SS components.
 At an average flow rate of 0.5-0.6 m/min in theplate settler module with the detention time ofabout 10 min, effluent quality is equivalent to
the one from conventional setting tanks.
 PAC is most suitable as a coagulant for wet
weather sewage sedimentation process.
 By adding PAC at the concentration of 2.5-10
mg-Al/L, influent sewage with BOD of 100-200
20/40
mg/L can be treated to produce an effluent with


18

Findings from Basic Studies andExperiments

Plate Settler Sedimentation
Process with Coagulant
Addition- 376 -In order to utilize
the existing
sedimentation tankeffectively, it isnecessary to place
multiple plate
settler modules inthe tank anddistribute theinfluent sewage toeach module.

Inffluent Main Pipe

Effluent

23/40

Effluent Main Pipe

300mm x 6 200mm x 4

Cross Section A-A
Perforated Pipes Perforated Pipes

Perforated Pipes 200mm x 5

Plan of Effluent Pipes
Effluent Main Pipe 600mm Effluent Main Pipe 500mm

Perforated Pipes 300mm x 5

Inclined Plate Module

Perforated Pipes 250mm x 5

Influent Main Pipe 600mm

Plan of Influent Pipes

Installation of Inclined Plate
Settler Modules

21/40

Since it is very difficult to acquire lands for theconstruction of new facilities, the city government
started design studies on modifying existing primary
sedimentation tanks to plate settler sedimentation
tanks using a pilot treatment facility at Chishima STP.

Chishima Sewage Treatment Plant

Modifying Existing Primary
Sedimentation Tanks

Influent

Vinyl chloride resin
Recycled plywood

Per

24/40

Influent main pipes are placed in the tank and connectedwith perforated pipes at their ends.
 Perforated pipes are vertically placed near the inlet crosssection of plate settler modules in order to distribute theinfluent sewage evenly in horizontal/vertical directions of
the module cross-section and to mitigate density currents.


22/40

Equalization of Influent Sewage
Distribution to Each Module

for
ate
1
#
for d pipe
n
i
in
s
ma
#2 distri fluen
ent
n
u
t
i
b
l
f
utio
Ef
ma
n
nt aineulmf
Ef entlu
InfIntervals of inclined plates:
100 mm Height of a settler module: 2.5 m
 Coagulant: PAC (JIS K 1475
Al2O3:10.0-11.0 wt%) Dosage of PAC: 3-10 mg-Al/L

Length of inclined plates: 3-6 m
 Angle of inclination: 60º
 Plate Material:Specifications





0

10

20

30

0

20

30

40

Surface Loading Rate (m3/m2·day)

10

50

50
150
250
350
450
550

50

40

Influent SS(mg/L)

60

27/40

Under the condition that the flow rate is less than
0.5m/min, it was observed that the effluent with
sufficient quality was obtained stably, when the surface
loading rate was less than 40m3/(m2·day).

Results of Performance Surveys
2) Influence of Surface Loading Rate

25/40

Sludge collectors were not installed, therefore, sludge
is stored on the bottom of the tank during rainfall
events. After rainfall events, water in the tank is once
drained together with most of the stored sludge. Then,the remaining sludge is flushed from the rear end of thetank using settled water from the adjacent settling tank.

Sludge Removal

Effluent SS (mg/L)

0

40
20

60

80

100

120

140

0

40
20

80
60

Under the condition thatthe flow rate is less than
0.5m/min and the surface
loading rate is less than
35m3/(m2·day), It is considered thatpollutants can beremoved to the level ofthe average effluent
quality at 20mg/L in SS
and 20-30 mg/L in BOD,
expect when the influent
pollutant load isextremely high.

0

10

20

30

40

50

60

45
40
35
30
25
20
15
10
5
0

0

0

50

100

100

150
200
250
Influent BOD (mg/L)

200
300
400
Influent SS (mg/L)

350

600

28/40

300

500

26/40

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
Flow Rate in the Plate Setter Module (m/min)

Influent
BOD(mg/L)
50
150
250
350
450

50
150
250
350
450
550

Influent SS(mg/L)

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
Flow Rate in the Plate Setter Module (m/min)

100

120

140

Results of Performance Surveys
3) Treated Effluent Quality

Under the condition thatthe surface loading rate isless than 35m3/(m2·day), Effluent SS concentration
increases when the flowrate exceeds 0.5m/min.
 Effluent BOD concentration
increases when the flowrate exceeds 0.55m/min.
 It is proposed that the flowrate in the plate settler
modules should be set
0.5m/min or less.

Results of Performance Surveys
1) Influence of Flow Rate
Effluent SS (mg/L)
Effluent BOD (mg/L)
Effluent SS (mg/L)
Effluent BOD (mg/L)- 377 -

- 378 -

0

0

50

100

100
150
200
250
Influent BOD (mg/L)

200
300
400
Inf luent SS (mg/L)

350

600

29/40

300

500

31/40

The city government is also conducting performance
surveys when applying this process to the primary
sedimentation process under dry-weather conditions.
 It is expected that the plate settler sedimentation process
will be able to have the equivalent treatment capacity ofthe existing primary sedimentation tank with 1/2-1/3 of its
original surface area.
 In this case, the remaining space can be used for wetweather sewage treatment by the plate settler
sedimentation process with coagulant addition.



0

20

40

60

80

100

100
90
80
70
60
50
40
30
20
10
0

Next Application of Plate Settler
Sedimentation Process

Under the same condition, The removal rate isapproximately 90% in SS
and 80% in BOD,
although it shows low
value when the influent
pollutant concentration is
at low level.

Results of Performance Surveys
4) Pollutant Removal Rate
SS Removal Rate (%)

BOD Removal Rate (%)



Newly Revised CSS
Improvement Plan of Osaka City

32

30/40

From the results of performance surveys, it isestimated that the existing primary sedimentation
tanks can be capable of treating wet-weather
sewage flow equivalent to 5 times its present
design maximum daily dry-weather flow, by
installing inclined plate settler modules with thefollowing specifications.
 Intervals of inclined plates: 100mm
 Flow rate in the settler modules: less than
0.5m/min Surface loading rate: 25m3/(m2·day)

Summary - Plate Settler
Sedimentation Process











Wet weather activated sludge process Plate settler sedimentation process Storage of wet-weather sewage using large
stormwater sewers designed for flood control
 Construction of wet-weather storage facilities

In the newly revised CSS improvement plan

Wet weather activated sludge process Filling sediment traps in manhole bottoms
 Replacement of screens Construction of stormwater reservoirs

In the previous CSS improvement plan

Major Approaches

The plate settler sedimentation process has
been developed to a practical level.

35/40

33/40

“The average quality of wet weather effluent during asingle rainfall event with the total rainfall of 10-30mm
should be not more than 40mg/L in BOD in eachtreatment area. (The tentative standard is 70mg/L
for the next 20 years.)”

In 2004, “Sewerage Law Enforcement Order”
was amended, and the wet weather effluent
quality standard for CSSs was newly stipulated.

Needs/Background for Revision(newly constructed)

Stormwater
Reservoirs

Temporary
Storage

3Qsh

反応槽

初
Primary
Sedimen
Reaction沈
tation
Tanks
等
Tanks
(for
(for
1Qsh)
3Qsh)

Exceeding 3Qsh (Direct discharge)

Final
Sedimentation
Tanks

1Qsh

2Qsh

36/40

Time

1Qsh

Sedimentation
2Qsh
only

Directdischarge

Secondary treatment

Temporarystorage(bystormwater
reserviors)

Image of Conventional Treatment
Process during Wet Weather

34/40

Mid-term Objectives (target year: 2018)
 Within each treatment area, the annual
discharge pollutant load including dry weather
periods should be reduced to the equivalentlevel of a separate sewer system (18mg/L in
BOD).
 The wet weather effluent quality should meetthe standard stipulated in the Sewerage Law
Enforcement Order amended in 2004.
 The number of overflow events from CSO
outfalls should be reduced by half.

Objectives of the Revised CSS
Improvement Plan

Influent flow

- 379 終沈Project Cost

終沈

- 380 -

1Qsh
3Qsh
Wet簡易放流
weather
activatedsludge process

Table 1: Estimated Project Cost for CSS Improvement
Approaches
Cost (billion JPY)
Wet Weather Activated Sludge Process
18
Plate Settler Sedimentation Process
57
Construction of Storage Facilities
87
Other Approaches
Filling Sediment Traps in Manhole Bottoms
30
Replacement of Screens, etc.
Total
192

1Qsh

2Qsh

Time

37/40

Temporary Direct
storage discharge

39/40

For the previous improvement plan, the total project
cost was estimated to be about 300 billion yen.
 Whereas in the new improvement plan, which fully
utilizes existing facilities to increase the wet-weather
sewage continuous treatment capacity, the total projectis estimated to be about 200 billion yen, a saving ofabout 100 billion yen.



Stormwater
Reservoirs

Final
Sedimentation
Tanks
3Qsh



Wet
Weather
Activated
SludgeProcess
(for
3Qsh)
Final
Sedimentation
Tanks
1Qsh
3Qsh

1Qsh

2Qsh

3Qsh

Time

40/40

“Wet weather activated sludge process” and “plate
settler sedimentation process” have been developed toa practical as widely applicable economic continuous
treatment technologies, which can;
 Utilize existing facilities effectively,
 Reduce CSS improvement costs significantly,
 Show rapid impacts on CSS improvement, Facilitate the progress of CSS improvement, and Suggest that CSS has the potential to become themost appropriate water pollution control system fordensely populated urban areas where flood control isalso a critical issue.

38/40

Temporary Direct
storage discharge
Plate settler
sedimentation
with coagulant
addition
Wet簡易放流
weather
activatedsludge process

Reduction in the area for primary sedimentation
by high rate filtration or plate settler
sedimentation without coagulant addition

Plate
初Settler沈
Sedime等
ntationPrimary
sedimentationSummary

Stormwater Sewers
Storage Facilities

Temporary
Storage

3Qsh

3Qsh

Increase in WWF
treatment capacity

Reduction in direct discharge

Install additional treatment
devices for remaining area

Exceeding 6Qsh (Direct discharge)

反応槽(newly constructed)

Temporary
Storage

3Qsh

反応槽

Wet
初
Primary
Weather
Sedimen
沈
Activatedtation等
SludgeTanks
Process
(for
(for
3Qsh)
3Qsh)

Exceeding 3Qsh (Direct discharge)

Influent flow

Image of Wet Weather Sewage
Treatment in the New Plan

Influent flow

Image of Wet Weather Sewage
Treatment in the Previous Plan

終沈

Fate of estrogens in sewage treatment process andeffect of treated sewage on fish
Koya Komori *, Yuji Okayasu*, Kiyoshi Miyajima*, Tadashi Higashitani*, Norihide Nakada*
and Yutaka Suzuki ** Water Environment Research Group, Public Works Research Institute, 1-6, Minamihara, Tsukuba City, Ibaraki, 305-8516,
Japan( komori@pwri.go.jp ; okayasu@pwri.go.jp ; miyajima@pwri.go.jp ; higashi44@pwri.go.jp ; nakada55@pwri.go.jp ;ysuzuki@pwri.go.jp )Abstract: Estrogens in treated sewage are suspected to pose an endocrine disrupting effect on fish, but it is becoming clear that mostof the estrogens can be removed in a sewage treatment process. However, the knowledge about the relation between operation
conditions and removal efficiency and the accurate fate in a sewage treatment process are restricted. Moreover, it cannot be said thatsufficient information has been obtained about the effect of treated sewage on fish. This paper reports the results of a review of therelationship between MLDO concentration and estrogen removal in aeration tanks of activated sludge process, and the biologicalimpact of treated sewage. The batch experiment where MLDO is controlled was conducted. Although no major change in E1 wasobserved when MLDO was still at a low level, it was confirmed that E1 concentration suddenly dropped when MLDO reached 3
mg/L. The rate of E1 reduction is speculated to depend closely on the concentration of dissolved oxygen. The exposure of medaka totreated sewage lead to the clarification of the relationship between estrogenic activity and the vitellogenin concentration in the sample
water. It was also confirmed that the higher estrogenic activity, the higher the rise seen in vitellogenin concentration.
Keywords: estrogens, estrone, 17ȕ-estradiol, feminization of fish, medaka,

Introduction³Our Stolen Future,´ authored by Dr. Theo Colborn et al., was translated into Japanese and published in September 1997. This bookbrought the problem of endocrine disruptors (EDs), popularly called environmental hormones, to public notice in Japan. Since then, avariety of investigations and surveys have been conducted in the field of sewage treatment. Since environmental hormones are known
to be able to affect life at even extremely low concentrations, they have drawn a veryhigh level of public concern. The Ministry ofLand, Infrastructure andTransport (MLIT), as well as local governments and research institutes, have engaged in active research fromthe viewpoint of preventing any impact on human health and the ecosystem.
Following an investigation of 47 sewage treatment plants conducted jointly by MLIT and local governments, a report was issued
noting that levels of environmental hormones in sewage influent were greatly decreased during the sewage treatment process, andmany substances decreased by over 90%,. Estrogens originating in humans and animals (17ȕ-estradiol or E2 and estrone or E1)
showed a steep drop in levels in discharged water. Most of those substances were in the form of estrones [MLIT, 2001]. However,there is a conspicuous lack knowledge of the details of the behavior of estrogens during the sewage treatment process and therelationship between the operating conditions of the plant and the removal efficiency. To help sewage treatment plants adopt specificstrategies to minimize outflow of these trace chemicals in the future, it is necessary to accumulate the basic information required tohelp predict and evaluate the impact of the operational conditions of the sewage treatment plant on the discharge of these chemicals tothe environment.
The numerous reports have been issued in Europe and North America on anomalies in reproductive organs of wildlife or theirabnormal reproductive conduct have propelled the environmental hormone issue to the top of the environmental agenda [e. g., Jobling
et al., 1996; Routledge et al., 1998; Gray et al., 1999; Metcalfe et al., 2001; Jones et al., 2003]. Some of the phenomena reported
include the feminization of male river fish living near the discharge ports of sewage treatment plants, with hermaphrodite fish observed

1- 381 -

to have eggs inside their testes [Routledge et al., 1998]. The causes of these phenomena are probably disturbance of the fish endocrine
system by chemicals emitted as a result of human activity. The chemicals that predominantly cause feminization are reported to be
estrogens, including E2 and E1, and a synthetic estrogen, 17D-ethynylestradiol or, EE2. However, there are fewer reports in Japan on
the biological impact of treated sewage and sufficient findings have not been obtained. In urban areas, the ratio of treated sewage in theflow of rivers to which sewage treatment plants discharge water is increasing, making it urgentlynecessary to clarify the biologicalimpact of treated sewage.
This paper reports the results of a review of the relationship between MLDO concentration and estrogen removal in aeration tanks ofactivated sludge process, and the biological impact of treated sewage.

Estrogen-like Activity in Sewage Influent, Treated Sewage and River water

Non--exceeding probability (%)

The EDs that most noticeably cause feminization are called estrogen-like substances, since they cause conditions similar to thosegenerallyresulting from the presence of estrogen inside the body. They can be measured as estrogenic activity (17ȕ-estradiol or E2
activity equivalent) using DNArecombinant yeasts with estrogen receptor genes. In our experiments, estrogenic activity was measured
using a DNArecombinant yeast stock provided by Prof. John Sumpter of Brunel University, UK. The DNArecombinant yeast isdesigned to generate ȕ-galactosidase when estrogens or estrogen-like substances bond with estrogen receptors (ERs). For themeasurement of estrogenic activity using the DNArecombinant
100%
yeast method, we followed the method developed byYakou et al.
90%
80%[Yakou, 1999], itself an improved version of the method ofTreated sewage
70%
n=77
Routledge et al.
60%
Figure 1 shows the distribution of estrogenic activity concentrationin sewage treatment plants and rivers in Japan. About 80% of
estrogenic activity was removed in the treatment processes ofsewage treatment plants on average; however, the treated sewage
still carries a concentration of 16 ng/l-E2 activity equivalent(medium) on discharge to the environment. This concentration is ahundred times higher than the median concentration in rivers,
which predicts a rise in estrogenic activity if the ratio of treatedsewage to the entire flow of a river increases.

50%
40%
30%
20%
10%
0%
0.01

River water
n=167

0.1

Sewage influent
n=87

1

10

100

1000

10000

Estrogenic activity as E2 equivalent (ng/L)

Figure 1:䇭Concentration distribution of estrogenic activity
in sewage influent, treated sewage and river water

Estrogenic activity䇭䋨ng/L-E2䋩

Theoretical activity was calculated from the concentrations of E1, E2 and nonylphenol (NP) obtained from chemical analysis of the
sewage influent and treated sewage of 25 sewage treatment plants. We studied to what extent these substances contributed to estrogenic
activity as obtained using the DNA recombinant yeast method. The estrogenic activity at each treatment plant and the corresponding
theoretical values of E1, E2 and NP are shown in Figure 2.
Although there are numerous samples that can be explained by
Theoretical values
YESNP
the presence of these three substances, many still defy such
100
E2
Sewage influent
E180
explanation, with the ratio between them varying according to60
treatment plant. It was also found that more than half of the 25
40
20
samples taken from both the sewage influent and treated0㪐 㪈 㪏 㪎 㪌 㪊 㪈㪏 㪉㪋 㪈㪐 㪉㪈 㪉㪌 㪉 㪈㪊 㪍 㪈㪇 㪉㪇 㪈㪎 㪉㪉 㪈㪈 㪈㪋 㪉㪊 㪋 㪈㪍 㪈㪌
sewage had a high content of estrogen-like active substancesthat cannot be traced to these three substances alone. To
100
Treated sewage
80
ascertain the contribution of each such substance, although60
there are some samples in the sewage influent that contain E1,40
20
E2 and NP each at certain levels, we took numerous samples0㪐 㪈㪈 㪈㪎 㪏 㪉㪇 㪉㪈 㪋 㪈㪇 㪉㪊 㪈㪏 㪉㪌 㪈㪐 㪊 㪉 㪍 㪉㪋 㪎 㪉㪉 㪈㪋 㪈㪌 㪈 㪈㪍 㪌 㪈㪉 㪈㪊from treated sewage that had a high E1 content. It was found
WWTP
that E1 is an important contributory substance for the
Figure 2: Contribution of each substance to estrogenic activity
estrogenic activity seen in treated sewage.

2- 382 -

Investigation of Behavior of Estrogen in Sewage Treatment Plants
Investigation method
We investigated a sewage treatment plant that serves 30,500 people with a conventional activated sludge process with a daily capacityof 20,400 m3 in January and July 2004. For both investigations, samples were taken from each treatment process every 2 hours over 24hours, and composite samples over 24 hours for flow proportion were prepared. The samples were analyzed for E2, E1, nonylphenol,
estrogenic activityas well as the items listed in environmental quality standards related to the preservation of the living environment,such as SS and BOD.

Results and discussion
The samples from both dates show a good removal efficiency (over 90%) for SS, BOD and COD, but the removal ratio of T-N turned
out to be low for the winter samples (16% in winter as opposed to 41% in summer). The samples from both seasons had a highremoval efficiency for E2 (70% in winter and 87% in summer), whereas the concentration of E1 increased as treatment proceeded(740% up in winter and 50% up in summer) with this trend particularly prominent in winter. For estrogenic activity (Fig. 3), theactivity level for the winter investigation rose as the treatment proceeded (removal efficiency of ±97% in winter, but 39% in summer).
in Winter survey

Recycle flow

44

1895
1355

1140 1450
500 mg/day
E2 equivalent

A

B

Drained sludge

CD

976 mg/day
E2 equivalent

Return sludge

36

1048

in Summer survey
Recycle flow

1036
739 mg/day
E2 equivalent

A

886

440

459
C

B

D

Drained sludge
Return sludge

1462

339 mg/day
E2 equivalent

Dissolved
Suspended

Figure 3: Mass balance of estrogenic activity (a, in mg/day, E2equivalent)through physicochemical treatment (A and C), biological treatment (B), and chlorination
process (D) during winter and summer in a municipal sewage treatment plant in Japan.
A: Primary settling tank; B: Aeration tank; C: Final settling tank D: Chlorination tankAccording to E1, E2 and NP concentration quantified by LC/MS/MS or HPLC analysis, the majority of estrogenic activity values
detected in samples of each sewage treatment process were attributable to E1. In the summer, the plant was operated with a level of
SRT and DO concentrations that promote nitrification, but in winter, the plant was operated at a reduced DO concentration in theaeration tank to reduce nitrification. These operation conditions mayhave affected the treatment of estrogen.

Relationship between MLDO concentration in the aeration tank and estrogen removal
As mentioned earlier, it is possible to speculate that removal of estrogen is affected by its relationship with the operational conditions of
the sewage treatment plant (DO control).A batch experiment was therefore conducted to clarify the relationship between the MLDO
concentration in the aeration tank and estrogen removal to find appropriate operation conditions that can stably reduce estrogen in the
sewage during treatment.

MethodAnalysis of the substances under study
Eight estrogens were to be investigated, including E2, E1, estriol (E3), and EE2 as well as sulfate conjugates of E2, E1 and E3, or
estrone-3-sulfate (E1-S), ȕ-estradiol-3-sulfate (E2-S), estriol-3-sulfate (E3-S), and estradiol 3, 17-disulfate (E2-diS). These substances

3- 383 -

were measured using the solid-phase extraction-LC/MS/MS method. The details of the analysis method are shown in the literature[Komori et al., 2004].

Investigation method
An aerobic batch experiment to simulate the treatment process in the plug flow type aeration tank (experiment duration: 8 hours) was
conducted using the effluent from the primary settling tank and returned sludge to investigate changes in the levels of estrogen-related
substances in the aeration tank of sewage treatment plant. The effluent from the primary settling tank and returned sludge were obtained
from the conventional activated sludge process pilot plant (aeration tank 2 m3 in capacity) using the sewage influent of the plant. The
experimental equipment used is a 150-L stainless steel container fitted with an agitator, into which 55 L of the effluent from the primary
settling tank and 25 L of returned sludge were fed and agitated. The water was aerated by air pumps through the air stones, and theaeration blow was adjusted to give an oxygen level of 3.0 mg/L by controlling the blow synchronously with the readings of theadditionally fitted dissolved oxygen meter.

Results and discussion

5.0
4.0
3.0
2.0
1.0
0.0

0

2

4

6

8

Elapse of time [hour]

E2

120

E1

E3

Concentration [ng/L]

DO

Concentration [ng/L]

pH

8.5
8.0
7.5
7.0
6.5
6.0
5.5

DO [mg/L]

pH [䋭]

Figure 4 shows temporal changes in pH, MLDO and estrogen in the aeration tank solution. When the experiment began, the dissolved
oxygen supplied by aeration was initiallyrapidly consumed, leading to pseudo-anaerobic conditions. After one hour had elapsed,
MLDO began to appear. It reached the set value of 3.0 mg/L in 7 hours. Levels of E2, which is a free estrogen, declined to below thedetection limit under these pseudo-anaerobic conditions in 2 hours. There were no major changes in E1 until 6 hours after the start ofthe experiment. However, its concentration suddenly dropped when MLDO began to rise. As explained above, it is assumed that the
reduction rate of E1 closely depends on the dissolved oxygen concentration. No EE2 was detected in any of the samples (detection
limit: 0.5 ng/L). For the estrogen sulfate conjugates, E1-S and E3-S were lower than the level of free estrogen, while E2-S is almost
equal to the free estrogen. E2-diS was detected at high concentrations. E1-S, E2-S and E3-S declined in the initial stages of theexperiment, while E2-diS showed almost no change.

100
80
60
40
20
0
0

2

4

6

Elapse of time [hour]

8

1000

E1-3S

E2-S

E3-S

E2-diS

100
10
1
0

2

4

6

8

Elapse of time [hour]

Figure 4: Temporal changes in pH, MLDO and estrogens

Effect of Treated Sewage on Fish
Effect of estrogen on Japanese medaka (Oryzias latipes)
An exposure experiment using adult male medaka in the laboratorywas conducted with E2 and E1 as the substances under study toobtain basic knowledge on the effects of exposure to medaka of the treated sewage. Vitellogenin concentration in the livers of thesample medaka was measured to identify the minimum effective concentration and maximum ineffective concentration of E2 and E1
and the relationship between the exposure time and the concentration of vitellogenin.

Methods
Five test concentrations of E2 and E1 were used: 5.0, 12.6, 31.6, 79.5 and 200 ng/L. The sample medaka were about 5 months old,
mature male medaka hatched from eggs taken from a group continuously raised in captivity for over three generations. The sample
medaka were selected from a group of medaka that had been raised up to four months, to the maturing stage, as above, and werescreened by sex based on their secondary sexual characteristic (shape of anal fin). Male fish alone were selected from the group andraised together until the experiment.
Sixty sample fish were used for each test section. They were exposed to the test water in flowing-water exposure equipment placed in aconstant-temperature chamber lined with a stainless steel interior finish. The test water tank was made of hard glass with an effective
water capacity of 10 L. The exposure time was 14 days.

4- 384 -



Results and discussion
100000Figures 5 and 6 plot changes in vitellogenin concentration in theliver during the exposure time for E2 and E1. For vitellogenin in
the control section, every individual was subjected to aconcentration of lower than 1 ng/mg throughout the exposure
period.
For E2, vitellogenin in the liver tends to rise in concentration in
proportion to E2 concentration for each exposure period. On the
2nd and 7th day of exposure, no significant difference wasobserved between the measurement in the 5.0 ng/L section andthat in the control section, but a significant difference appeared(p < 0.01) for the measurements on the 14th day of exposure.
For E1, no significant difference was observed at a standard of
p < 0.05, in comparison with the control section in eachexposure period for the below 31.6 ng/L concentration sections.

Control
31.6 ng/L

5.0 ng/L
79.5 ng/L

12.6 ng/L
200 ng/L

Vitellogenin conc. (ng/mg-liver)

10000

1000

100

10

1

0.1
0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

Exposure days

Figure 5: Temporal changes in vitellogenin concentration in
the liver as result of exposure to E2

Vitellogenin conc. (ng/mg-liver)

For the 79.5 ng/L and 200 ng/L sections, a significant
100000Control
5 ng/Ldifference (p < 0.01) was observed from the measurement in
12.6 ng/L
31.6 ng/L
the control section on the 3rd, 7th and 14th day of exposure.
79.5 ng/L
200 ng/L
10000
Of the concentrations of vitellogenin in each exposure period,
1000
the lowest concentration (set concentration) that showed asignificant difference (p < 0.05) from the control section is100
defined as the minimum effective concentration, while the10highest concentration showing no significant difference is1defined as the maximum ineffective concentration. The
minimum effective concentration of E2 was 12.6 ng/L for the
0.1
2 day and 7 day exposure period and 5.0 ng/L for the 14 day
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14
period. The maximum ineffective concentration was 5.0 ng/L
Exposure days
Figure 6: Temporal changes in vitellogenin concentration inand <5.0 ng/L, respectively. The minimum effective
the liver as a result of exposure E1
concentration of E1 was 79.5 ng/L for the 3-day, 7-day and
14-day exposure periods, while the maximum ineffective concentration was 31.6 ng/L for all. Effective concentrations of 17ȕ-estradiol
and estrone are put together in a list as shown in Table 1.

Table 1: Effective concentration of 17Ǫ-estradiol and estrone
Substances under study

Exposure time(day)

17E-estradiol

EstroneMaximum ineffective concentration Minimum effective concentration(ng/L)(ng/L)

2

5.0

12.6

7

5.0

12.6

14

< 5.0

5.0

3

31.6

79.5

7

31.6

79.5

14

31.6

79.5

Impact on medaka of treated sewage
Methods
The influence of treated sewage on medaka was analyzed using the fish exposure test equipment placed in the sewage treatment plant.
The equipment consists of three water tanks: the first tank removes sand and mud, the second tank maintains the water temperature at
25 ÛC, after which the water is led to the third tank (30 L) for exposure of medaka to the treated sewage.
The exposure test was conducted on adult medaka fish in treated sewage and sand-filtered water (Test A). Sixty male medaka and 10
female medaka were put in both the treated sewage section and the sand-filtered water section and exposed to the water for 6 weeks.

5- 385 -



The other exposure test was conducted in treated sewage and sand-filtered water, on juvenile and freshly hatched medaka (Test B).
Twenty freshly hatched fish were put in both the treated sewage section and the sand-filtered water section and exposed for 8 weeks.
Estrogenic activity in the treated water and vitellogenin concentration in the medaka fish were measured during the test periods of both
Test Aand B.

Results and discussion
VTG concentrationࡆ࠹ࡠࠫࠚ࠾ࡦỚᐲ

Estrogen-like
Estrogenic
activity
activityࠛࠬ࠻ࡠࠥࡦ᭽ᵴᕈ
ࠛࠬ࠻ࡠࠥࡦᵴᕈ
40

8Effluent fromsecondary settling tank
ੑᰴಣℂ᳓

6

20

4

Test A

8th week

6th week

4th week

2nd week

Test start

6th week

4th week

2nd week0

Test start

Vitellogenin concentration (ng/mg-liver)20

Test B40

8Effluent from sand filtration⍾䉐ㆊ᳓

6

Estrogenic activity (ng/L-E2)

Changes in the level of estrogenic activity and the concentrationof vitellogenin in the test are shown in Figure 7. In Test A,
vitellogenin was found to have formed in the male medaka in
the treated sewage section and the sand-filtered section. The
level of estrogenic activity in both test sections was above 20
ng/L-E2 on the start of the test, but it subsequentlynever rose
above 10 ng/L-E2. This fact suggests that the enhanced level of
estrogen action seen at the start of the test was responsible forformation of vitellogenin in the medaka. The authors speculatethat vitellogenin, once formed, will stay inside the body until
metabolized. For Test B, male medaka produced vitellogen in
the 8th week in the treated sewage section, where a rise inestrogenic activity beyond 20 ng/L-E2 in the 6th week was
observed. As explained earlier, the concentration of estrogens,attributable to the formation of vitellogen in male medaka was
12.6 ng/L for the minimum effective concentration of E2 (2ndand 7th day of exposure), and the maximum ineffective
concentrations were 5.0 ng/L (2nd and 7th day of exposure).
Judging from this observation, it is possible that vitellogenin wasformed as early as on the 2nd day of exposure when exposed to
E2 at above 10 ng/L. This appears to be in agreement with theresults of TestsAand B obtained from the experiment at the
sewage treatment plant.

20

4

Test A

8th week

6th week

4th week

2nd week

Test start

6th week

4th week

Test start0

2nd week

20Test BVTG concentration ng/mg-liver)

Figure 7: Changes in estrogenic activity and vitellogenin
concentration in the experiment

The relationship between estrogenic activity and vitellogenin
concentration in the sample water when medaka were exposedto the treated sewage is shown in Figure 8. Although there is alarge variation, there is a tendency to show a higher estrogenic
activity the more the vitellogenin concentration rises.

10000
1000
100
10
1
0
0

1
10
Estrogenic activity㧔ng/L-E2㧕

100

Figure 8: Relationship between estrogenic activity in thesamples and VTG concentration in the livers of the mal
medaka individuals in the exposure test

Conclusions
1) The concentration levels of estrogenic activity in the sewage influent, treated sewage and river water show that the level of estrogenic
activity in the sewage decreases by about 80% during the treatment process at the sewage treatment plant, but the treated sewage
containing a concentration of 16 ng/L-E2 activity equivalent (median) is discharged to the environmental water. This level is two digits
higher than the concentration in the river water (median). As the ratio of treated sewage to the flow of a river rises, the level of estrogenic
activity is predicted to rise.
2) Estrogenic activity in the sewage indicates that substances not traced back to E1, E2 and NP are contained in water samples. For thecontribution of each substance, E1, E2 and NP are respectively responsible for raising the level of estrogenic activity in the sewage
influent. It is thus confirmed that E1 has a high contributoryrole in the treated sewage and that E1 plays an important role as a major
substance that enhances estrogenic activity in the treated sewage.

6- 386 -

3) Behavior of estrogens in the sewage treatment plant was investigated in winter and summer. Although the removal ratio for E2 wasfound to be high in both seasons (70% for winter and 87% for summer), the concentration of E1 rises with the progress of treatment(740% up in winter and 50% up in summer), and this tendency is particularly conspicuous in winter.
4) The batch experiment where MLDO is controlled was conducted. Although no major change in E1 was observed when MLDO was
still at a low level, it was confirmed that E1 concentration suddenly dropped when MLDO reached 3 mg/L. The rate of E1 reduction is
speculated to depend closely on the concentration of dissolved oxygen.
5) The influence of estrogen on the formation of vitellogenin in male medaka was investigated. The maximum ineffective andminimum effective concentration of E2 in the 14-day exposure test were <5.0 ng/L and 5.0 ng/L, respectively. The maximum
ineffective and minimum effective concentrations of E1 were 31.6 ng/L and 79.5 ng/L, respectively.
6) Male medaka fish were exposed to treated sewage and sand-filtered water. The results confirmed that vitellogenin had formed in the
medaka in the treated sewage in which the estrogenic activityhad risen above 20 ng/L-E2. The exposure of medaka to treated sewage
lead to the clarification of the relationship between estrogenic activity and the vitellogenin concentration in the sample water. It wasalso confirmed that the higher estrogenic activity, the higher the rise seen in vitellogenin concentration.

Acknowledgment
The authors thank the local governments for kindly providing wastewater samples. We also thank the laboratory staff who prepared thesamples for the estrogen-like activity and the LC/MS/MS analyses.

References
Gray, M. A.; Thather, K. L. and Metcalfe, C. D. (1999): Reproductive success and behavior of Japanese medaka (oryzias latipes)
exposed to 4-tert-octylphenol, Environmental Toxicology and Chemistry (18) 11, 2587-2594
Jobling, S.; Sheahan, D.; Osborne, J. A.; Matthiessen, P. and Sumpter, J. P. (1996): Inhibition of testicular growth in rainbow trout(oncorhynchs mykiss) exposed to estrogenic alkylphenolic chemicals, Environmental Toxicology and Chemistry (15) 2,
194-202
Jones, E. T.; Thorpe, K.; Harrison, N.; Thomas, G.; Morris, C.; Hutchinson, T,; Woodhead, S. and Tyler, C. (2003): Dynamics of
estrogen biomarker responses in rainbow trout exposed to 17D-ethnylestrdiol, Environmental Toxicology and Chemistry(22) 12, 3001-3008
Komori, K.; Tanaka, H.; Okayasu, Y.; Yasojima, M. and Sato, C. (2004): Analysis and Occurrence of Estrogen in Wastewater in Japan,
Water Science & Technology (50) 5, 93-100
Metcalfe, C. D.; Metcalfe, T. L.; Kiparissis, Y.; Koenig, B. G.; Khan, C.; Hughes, R. J.; Croley, T. R.; March, R. E. and Potter, T.
(2001): Estrogenic potency of chemicals detected in sewage treatment plant effluents as determind by in vivo assays withJapanese medaka (oryzias latipes), Environmental Toxicology and Chemistry (20) 2, 297-308
Ministry of Land, Infrastructure andTransport, MLIT, (2001): FY2000 Results of a Fact-finding Study of Endocrine Disruptors in
Water Environments, Ministry of Land, Infrastructure and Transport (in Japanese).
Routledge, E.J.; Sheahan, D.; Desbrow, C.; Brighty, G. C.; Waldock, M. and Sumpter, J. P. (1998): Identification of estrogenic
chemicals in STW effluent. 2. in vivo responses in Trout and Roach, Environmental Science & Technology, 32, 1559-1565
Yakou, Y.; Takahashi, A.; Higashitani, T. and Tanaka, H. (1999): Measurement of Estrogen-like Activity in Wastewater Using
Recombinant Yeast, Environmental Engineering Research, 36, 199-208, Japan Society of Civil Engineering, (in Japanese).

7- 387 -



- 388 -9 Introduction and Objectives
9 Estrogn-like activity in sewage influent,treated sewage and river water
9 Investigation of behavior of estrogen in
sewage treatment plants
9 Relationship between MLDO concentrationin the aeration tank and estrogen removal
9 Effect of treated sewage on fish
9 Conclusion

Outline of the presentation

Water Environment Research Group
Public Works Research Institute (PWRI)

Koya Komori, Yuji Okayasu, Kiyoshi Miyajima,
Tadashi Higashitani, Norihide Nakada and Yutaka Suzuki

Fate of estrogens in sewage
treatment process andeffect of treated sewage on fish

10th Japanese German Workshop on Water Technology
Hotel Courtyard Marriott, Berlin
09.10-10.10.2006

3

1“Our Stolen Future” wastranslated into Japanese andpublished in September 1997

“Our Stolen Future”

translated by
Tsutomu Nagasaka

byTheo Colborn,
Dianne Dumanoski
andJohn Peterson Myers

9 Introduction and Objectives
9 Estrogn-like activity in sewage influent,treated sewage and river water
9 Investigation of behavior of estrogen in
sewage treatment plants
9 Relationship between MLDO concentrationin the aeration tank and estrogen removal
9 Effect of treated sewage on fish
9 Conclusion

Outline of the presentation

42

- 389 - The biological impact of treated sewage(Effect of treated sewage on fish) A review of the relationship between
MLDO concentration and estrogen removal inaeration tanks of activated sludge process

Objectives

1) MLIT, (2001): FY2000 Results of a Fact-finding Study of Endocrine Disruptors in
Water Environments, Ministry of Land, Infrastructure and Transport (in Japanese)

Substances

7

5

RemovalMedian concentration (μg/L)
Sewage influent Treated sewage efficiency
Nonylphenol (NP)
4.4
Trace (0.2)
95 %Bisphenol-A
0.53
Trace (0.02)
96 %2,4-dichlorophenol
0.07
N.D.
99 %
Diethyl phtalate
3.1
N.D.
99 %
Di-n-butyl phthalate
2.6
N.D.
99 %
Di (2-ethylhexyl) phthalate
12
Trace (0.4)
97 %Di (2-ethylhexyl) adipate
0.09
N.D.
99 %
Benzophenone
0.17
0.05
71 %
ELISA
0.042
0.01
76 %
17b-estradiol (E2)
LC/MS/MS
0.0081
N.D.
99 %Estrone
LC/MS/MS
0.043
0.006485 %Concentration of environmental hormones insewage influent and treated sewage 1)
Place

Influences

Probablecausative
substances
organotin
components
nonylphenol*not confirmed
nonylphenol*not confirmed
Researchers

9 Introduction and Objectives
9 Estrogn-like activity in sewage influent,treated sewage and river water
9 Investigation of behavior of estrogen in
sewage treatment plants
9 Relationship between MLDO concentrationin the aeration tank and estrogen removal
9 Effect of treated sewage on fish
9 Conclusion

Outline of the presentation

seashores invirilescence,
Horiguchi et al.
shellfish
reishiaJapan
population(1994)
rivers in thevirilescence,
Sumpter et al.
rainbow trout
United Kingdom
population(1985)
Purdom et al.
roachrivers in thehermaphroditism
fish(1994)(a kind of carp) United Kingdom
thyroid
Great Lakes inLeatherland
hyperplasia,
unknown
salmonthe United(1992)
population
Statesorganochlorine
male penis
agriculturalatrophy,lakes in Florida
chemicals such Guillette et al
decrease of
reptilescrocodile
State in the(1994)
as DDT
hatchability ofUnited Statesdischarged into
ovum,
lakes
population
Cf. Quoted works are based on "the interim reports by the workshop concerning exogenous endocrinedisrupting chemicals issues."2) http://www.env.go.jp/en/chemi/ed/speed98/sp98t2.html

Wildlife

The report concerning the influences on wildlife 2)86

- 390 -

1

10

100

N=87

1000

MedianSewage Influent

10000(E2 : 17β-estrdiol)

Estrogenic activity，ng/L,E2-equivalent (ng/l)

0.1Median 16

N=167

N=77

Treated sewage

MedianRiver water

Outline of the presentation

100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
0.01

9 Introduction and Objectives
9 Estrogn-like activity in sewage influent,treated sewage and river water
9 Investigation of behavior of estrogen in
sewage treatment plants
9 Relationship between MLDO concentrationin the aeration tank and estrogen removal
9 Effect of treated sewage on fish
9 Conclusion

Non-exceeding probability

Concentration distribution of estrogenic activity insewage influent, treated sewage and river water

11

9

4

8

2 19 17 9 18 3 12 10 23 14 25 21 1 20 15 24 4 16 5

6 13 11 8 22 7

1 14 24 21 3 25 20 7 15 10 18 17 16 19 5 23 12 11 6Treated Sewage

2 13 9Sewage Influent

YES
E2
E1

Drained sludge

A

1036

Recycle flow

36

886

1140 1450

Drained sludge

A

44

Recycle flow

Capacity: 20,400m3/day

739 mg/day
E2 equivalent

in Summer survey

500 mg/day
E2 equivalent

in Winter survey

Return sludge

BB

459

Return sludge

BB

1895

C

C

1462

440

1048

1355

D

D

12

Dissolved
Suspended(mg/day, E2equivalent)

339 mg/day
E2 equivalent

A: Primary settling tank
B: Aeration tank
C: Final settling tank
D: Chlorination tank

976 mg/day
E2 equivalent

10

Nonyl phenol

Mass balance of estrogenic activity in a municipal
sewage treatment plant

0

20

40

60

80

100

0

20

40

60

80

100

Contribution of Estrogens and Nonylphenol in Estrogenic
Activity of Sewage Influent and Treated Sewage

Estrogenic Activity, ng/L-E2 equivalent

0

20

40

60

80

100

120

0

4

E1

6

Elapse of time [hour]

2

E2

E3

8

0

0

2

6

8

1

10

100

1000

4

6

E2-diS

E3-S

Elapse of time [hour]

2

E2-S

E1-3S

8

0.0

5.5

Elapse of time [hour]

1.0

6.0
4

2.0

6.5

7.0

3.0

5.0
4.0

DO

7.5

pH

8.0

8.5

9 Introduction and Objectives
9 Estrogn-like activity in sewage influent,treated sewage and river water
9 Investigation of behavior of estrogen in
sewage treatment plants
9 Relationship between MLDO concentrationin the aeration tank and estrogen removal
9 Effect of treated sewage on fish
9 Conclusion

Outline of the presentation

Temporal changes inpH, MLDO andestrogens

Concentration [ng/L]

pH [－]

Concentration [ng/L]- 391 DO [mg/L]

15

13

Air pump

DO
controlunit

9 Introduction and Objectives
9 Estrogn-like activity in sewage influent,treated sewage and river water
9 Investigation of behavior of estrogen in
sewage treatment plants
9 Relationship between MLDO concentrationin the aeration tank and estrogen removal
9 Effect of treated sewage on fish
9 Conclusion

Outline of the presentation

E2, E1,E3, EE2,
E1-S, E2-S, E3-S,
E2-diS

16

14

Analytical estrogens

Experimental apparatus

Experiment duration: 8 hours

Collecting Sample

Mixer

DO meter

10 L

10 L

Overflow

HRT; 12 h

42 ml/min

10 L

P

Overflow

HRT; 12 h

42 ml/minP

10 L

Stock solution

Overflow

HRT; 12 h

42 ml/minP

10 L

Stock solution

0.1

1

10

100

1000

10000

100000

0

1

2

3

4

S.Control
31.6ng/L

5

7

8

Exposure days

6

5ng/L
79.5ng/L

910

12.6ng/L
200ng/L

11

12

13

14

Temporal changes in vitellogenin (VTG)
concentration in the liver as a result of exposure E1

Vitellogenin concentration in
the livers of the sample fishB
C
D
E
(12.6 ng/l) (31.6 ng/l) (79.5 ng/l) (200 ng/l)

Overflow

HRT; 12 h

P

Stock solutionz Test water: E2 & E1z Sample fish: 60 for each tankz Exposure time: 14 daysA
(5.0 ng/l)

Overflow

HRT; 12 h

42 ml/min

42 ml/min

P

Stock solution

Stock solution

19

17

0

1

2

3

4

Control
31.6ng/L

5

7

8
Exposure days

6

5.0ng/L
79.5ng/L

9

10

11

12.6ng/L
200ng/L

12

13

14

E1

E2

Substances
under study

Maximum
ineffective
concentration(ng/L)
5.0
5.0
< 5.0
31.6
31.6
31.6

Exposure time
(day)
2
7
14
3
7
14

12.6
12.6
5.0
79.5
79.5
79.5

Minimum
effective
concentration(ng/L)

Effective concentration of E2 and E1

0.1

1

10

100

1000

10000

100000Temporal changes in vitellogenin (VTG)
concentration in the liver as result of exposure to E2

Vitellogenin conc. (ng/mg-liver)

Effect of estrogen on Japanese medaka

Vitellogenin conc. (ng/mg-liver)- 392 20

18

Test B; juvenile and freshly
hatched medaka

Test A; adult medaka fish

Test Waterz Treated sewage
z Sand filtered water

0

1

10

100

1000

10000

0

1
10
Estrogenic activity（ng/L-E2）

100

Relationship between estrogenic activity in thesamples and VTG concentration in the livers of themal medaka individuals in the exposure test

30 L

The third tank(fish exposure tank)

23

21

Test A

Test A

Test B

Effluent from sand filtration
砂ろ過水

Test B

0

20

40

0

20

40

Vitellogenin concentration (ng/mg-liver)

9 Introduction and Objectives
9 Estrogn-like activity in sewage influent,treated sewage and river water
9 Investigation of behavior of estrogen in
sewage treatment plants
9 Relationship between MLDO concentrationin the aeration tank and estrogen removal
9 Effect of treated sewage on fish
9 Conclusion

Outline of the presentation

0

2

4

6

8

0
4th week
4th week

2
6th week
6th week

4

Test start
Test start

The second tank(maintains the water temperature)

Effluent fromsecondary settling tank
二次処理水

Estrogen-like
Estrogenic
activity
activity
エストロゲン様活性
エストロゲン活性

2nd week
2nd week

4th week
4th week

6

Test start
Test start

VTG concentration
ビテロジェニン濃度

6th week
6th week

8

8th week
8th week

The first tank(removes sand & mud)2nd week
2nd week

Changes in estrogenic activity andvitellogenin concentration in the experiment

Estrogenic activity (ng/L-E2)

Impact on medaka of treated sewage

VTG concentration ng/mg-liver)- 393 24

22

- 394 -z The estrogenic activity had risen above 20
ng/L-E2z The higher estrogenic activity, the higher
the rise seen in VTG concentration

3) Male medaka fish were exposed to treatedsewage and sand-filtered water

Conclusions (3/3)

27

We also thank the laboratory staff who
prepared the samples for the estrogen-like
activity and the LC/MS/MS analyses

The authors thank the local governmentsfor kindly providing wastewater samples

Acknowledgment

28

26

E2
E1
z Max. ineffective conc.; <5.0 ng/L 31.6 ng/L
z Min. effective conc. ; 5.0 ng/L 79.5 ng/L

Although no major change in E1 wasobserved when MLDO was still at a low level, it
was confirmed that E1 concentration suddenly
dropped when MLDO reached 3 mg/L
252) The influence of estrogen on the formationof VTG in male medaka was investigated

Conclusions (2/3)

1) The batch experiment where MLDO iscontrolled was conducted

Conclusions (1/3)

- 395 -its

Collaboration with Murata Keisokuki Service Co., Ltd.
& Kyoto University
29

z Development of simultaneous analysis of pharmaceuticals inaqueous samples using LC-MS/MS

Collaboration with Teijin Eco-Science Ltd .

z Analytical method of clarithromycin，erythromycin andmetabolite in waste waters

Collaboration with Towa Kagaku Co., Ltd.

z Development of analytical method for LVFX, CAM and AZM
in sewage samples
z Occurrence of LVFX, CAM and AZM in sewage treatment
plants in JapanThe latest research

30

Thank you for your attention

10th Japanese German Workshop on Water Technology
Hotel Courtyard Marriott, Berlin
09.10-10.10.2006

Degradability of Pharmaceuticals in the Aquatic EnvironmentProf. Dr. Klaus Kümmerer*
Institute for Environmental Medicine and Hospital Epidemiology,
Breisacherstraße 115b, D-79106 Freiburg, Germany

Chemicals are part of modern life. They are part of all spheres of human life. They
are used as pharmaceuticals, pesticides, detergents, fertilizers, dyes, pints, finish,preservatives, food additives and others. They contribute to our well being, highexpectancy of life and economical prosperity. There is also a back side of thissuccess story. If chemicals are not used in closed loops they can enter into theenvironment. Especially if they are used in everyday life and if they are constituentsand ingredients of consumer products they are emitted into the environment by non
point sources. After administration pharmaceutical substances are excreted by thepatients into waste water.

Outdated medicaments or reminders are sometimes

disposed in drains in households, presumably 20-40 % in Germany. Therefore,
pharmaceutical substances enter municipal sewage and sewage treatment plants. Ifthey are not eliminated during sewage treatment they are emitted into surface waterand can reach drinking water. This makes it difficult to hold them back efficiently.
A long half live in the environment results in a big temporal and spatial range.
Therefore, for persistent chemicals, a risk assessment is not possible. With bigger
scales involved uncertainty increases time and possible effects cannot be tested inlab trials. Persistency is therefore one of the most important criteria for theenvironmental assessment of chemicals. For persistent organic pollutants (POPs) the
Stockholm*

convention(http://www.pops.int/documents/context/

corresponding
author:phone:
Klaus.kuemmerer@uniklinik-freiburg.de*761/270-5464,- 397 -

fax:

convtext_en.pdf)+761/270-8235;

e-mail:came into force. Until now only 12 organo-halogen compounds the so called dirty
dozen are regulated under this convention among them polychlorinated biphenyls(PCBs), a classical example of persistent pollutants. PCBs have been synthesized forthe first time in 1877. In 1899 severe health problems (chloracne) associated with thehandling of PCBs had been reported. Throughout the years the poisoning of rice oilby these compounds and neurotoxic effects as carcinogenicity has been described indetail. Despite this knowledge it took until 1999 to ban PCBs fully within the EU – 100
years after the first reports of its severe toxicity! This example demonstrates that it is
not only the time scales of the chemicals itself and the environmental processes
impacted by them but also the time scales of economical and political systems.
Additionally, the use of persistent chemicals is often associated with high costs in thelong run – at least for the general public.
In the Stockholm convention a half life of more than 50 days in water is set as acriterion for POPs.

Recent research show that other chemicals that are lesspersistent and have higher polarity then the dirty dozen are distributed globally andcan accumulate in humans. A statistical correlation between the persistency ofchemicals and the prevalence of the presence of chemicals in the environment that
can initiate cancer has been reported only recently.
The potential for chemicals to undergo biotransformation is an important aspect ofassessing the environmental fate and risk of chemicals. Several different non-biotic
processes can result in the removal of chemicals from sewage, surface waters,
ground waters, drinking water processing, and soil. Biologically mediated processes(i.e. biotransformation) and non biotic processes can result in the full transformation
or mineralization of chemicals in the aquatic environment. In rare cases chemicals
are fully broken down to water, carbon dioxide and inorganic salts. Very oftentransformation is incomplete and unknown transformation products are formed.
- 398 -

Since the nineteen-eighties pharmaceuticals from different groups have been
detected in the environment (e.g. Kümmerer 2004). Only few data is currently
available concerning the biodegradability of antibiotic compounds in STPs andsurface water. It has been found that most pharmaceuticals are not biodegraded fully
in sewage treatment and in the environment. It has been found that in the case ofpharmaceuticals total degradation does take place only rarely and the process is
stopped before total mineralization. These intermediates (i.e. stable metabolites or socalled transformation products) of (bio)transformation can be even more stable thanthe parent compounds. They often also differ in terms of toxicity and have a different
potential for accumulation compared to the parent compound. This also holds true fordrugs which are excreted as conjugates after they have been hydroxylated ortransformed for instance into sulfates, glycosides and others. If at all, these products
are usually less active than the parent compound. They can also be regained by
microbial activity in the environment or in STPs.
If the parent compounds are degraded only partially resulting transformation productswith high stability under environmental conditions will remain in the environment too.
They can also be toxic against humans and environmental organisms. In this casethe situation may be worse as we have usually much less knowledge on the stabletransformation products and their fate and effects in the environment than on theparent compounds. Furthermore, if the input rate is higher than the rate ofdegradation or mineralization of chemicals they will nevertheless be present atconstant levels in the environment. This can be called persistency of second order or
pseudo persistency.
Kümmerer 2004: Pharmaceuticals in the Environment, 2nd Ed., Springer, Heidelberg New York Tokyo,
2004, 3rd Ed. In praparation- 399 -

- 400 0 - 20%

0 -100%0 - 50%0 - 50%0 - 50%20 - 80%

0 -100%

0 -100%10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

K. Kümmerer3

Hirsch et al. 1999, Ternes 1998ff, Heberer 1996ff, Richardson und Bowron 1985, ….

…., Golet et al. 2002, Färber et al. 2002, Kolpin et al. 2002, Sacher et al. 2001, Kümmerer et al. 2001, Zuccato et al. 2001,

Diagnostics(x-ray, MRI):•Pain killers•

Antidepressents

Statines•

Disinfectants:

Hormones:••

Zytostatics:••

Antibiotics:•

Elimination of Pharmaceuticals
in Sewage Treatment Plants

K. Kümmerer
2

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

K. Kümmerer
4

What Does Elimination Mean?

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th…, Färber et al. 2002, Kolpin et al. 2002, Sacher et al. 2001, Kümmerer et al. 2001, Hamscher et al. 2002, Zuccato et al.
2001, Hirsch et al. 1999, Ternes 1998ff, Kümmerer et al. 1996, 1997 Heberer 1996ff ,...

pseudo persistence!

• continuous emission into the environment:

Klaus.Kuemmerer@uniklinik-freiburg.de

phone: ++761-270-8235• in soil: antibiotics, growth promoters (up to 300 µg/kg, higher in manure)(also: diagnostics, disinfectants e.g. QACs)• from all therapeutical groups as far as studied up to now

water, drinking water in the ng/L-µg/L range• in hospital effluent, waste water, rivers, ground

A, AUS, BRA, CDN, CH, D, DK, GB, F, I, J, NL, S, USA, …

Reports from:

Detection of Pharmaceuticals
in the EnvironmentProf. Dr. Klaus Kümmerer

Berlin, October 9th-10th 2006

10th Japanese-German Workshop on Water Technology

Degradability of Pharmaceuticals
in the Aquatic Environment

F

N

N

S

O

OH

O

O

N

-

N

H
N

O

O

O

S

O-

N
+

H3C

H3C

Cl
O

O

O

H3 C

Cl

O
O

O

O

H3 C
O

CH3

OH

CH3

O

O

O

HO

O

H3 C

O

OH

OH

O

H3C-O-CH2

Cl

O

OH

Cl

H3 C

CH3

O

O-CH3

O

O
O

Cl

O

Cl
O

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

K. Kümmerer
7

O

O
OH

CH3

O O

Avilamycin A

CH3O

Ceftazidime Species as Function of pH

K. Kümmerer
5

O

N

H

zwitterionic!

O+

N
Ciprofloxacin

Ceftazidime HO

H2 N

O

N

OH

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

HN

CH3

K. Kümmerer
6

Zulaufinfluent

Ablaufeffluent

Belebtsludge
schlamm10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

0

20

40

60

80

100

K. Kümmerer
8

sludgeÜberschusssurplus
schlammAlexy, Sacher, Wenz, Kümmerer, submitted

0

20

40

60

80

100

Clarithromycin

effluent
AblaufsludgeBelebtschlamm

NOCH2OC2H5OCH3

influent
ZulaufRoxithromycin

surplusÜberschussschlamm
sludgeElimination of Antibiotics in a STP:
Impact of Structure

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Konzentration[ng/l] oder
ConcentrationTS]d.m.)(ng/L;[µg/kgµg/kg“Designed“ for bioactivity and stability, complex
molecules with several, often different functionalgroups!

Ciprofloxacin as Zwitterion (pH 6.5-8.0)

Concentration

Pharmaceuticals are Special!

Konzentration [ng/l] oder(ng/L;µg/kg[µg/kgTS]d.m.)- 401 -

0

5

10

15

20

25

30

I

H 2N

O

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

I

O
I

NH 2

OH

K. Kümmerer
11

I

O

CH3

• No elimination in STP(OECD 303A)• Toxicity ?

2 fold deacetylation

N
H

N
H

OH
I

O

I

A. Haiß, K. Kümmerer, Chemosphere, 62 (2006) 294–302

Diaminotrizioc acid(metabolite B)
Confirmed by MS, 1-H-NMR, IR

H3C

5

10

15

0

5

10

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Trautwein & Kümmerer, submitted

-20

0

20

40

60

80

100

120

20

25

20

K. Kümmerer
12

day

15

25

30

DOC-Elimination of
Verapamil-HCl in the ZWT

day

0

ATZA

Met-Bof production

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

0

200

400

sample day 23 Zahn-Wellens test

Sampling

Met-Adiamino trizoic acid,(intermediatein production
an intermediate

Transformation
product B

K. Kümmerer
10

Significance of Metabolites andTransformation Products?

Amidotrizoic acid (ATZA)

Transformation

600 product A

800

1.000

1.200

1.400

1.600

1.800

2.000

30

0

2

4

6

8

10

12

14

16

18

20

Verapamil-HCl
neg. control
Negativkontrolle

Verapamil-HCl 2

Verapamil-HCl 1

pos.
control
Positivkontrolle

Elimination of ATZA in the ZahnWellens Test (OECD 302B)

day

ATZA concentration in mg/l

K. Kümmerer
9

0

0

4
2

ATZA

6

200

400

600

Met-B

10

1.000
8

12

1.200

Met-A

14

1.400

800

16

1.600

20
18

Sampling

1.800

2.000

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Peak area (metabolites, rel. units)

Elimination of ATZA in the ZahnWellens Test (OECD 302B)
Peak area (metabolites, rel. units)

D O C -E lim in a tio n [% ]- 402 -ATZA concentration in mg/l

Trautwein & Kümmerer, in preparationprecursor ion

day 1
TIC and specific masses

0

10

20

K. Kümmerer
15

Abbautagday

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Kümmerer et al., submitted

0

20

40

60

80

100

K. Kümmerer
13

product ion

product ion

product ion

30

control

Piperacilin
Negativkontrolle
Piperacilin
HPLC, HPLC

Piperacilin
HPLCHPLC
Mittelw ert
Piperacilin

Piperacilin
Negativkontrolle
DOC
Piperacilin
DOC, control

Piperacilin
DOCDOC
Mittelw ert
Piperacilin

Elimination of Piperacilin:
DOC vs. HPLC-UV/Vis

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Elimination
Elimination bezogen
auf Kohlenstoff[%]

Elimionation (%)

product ion

K. Kümmerer
14

oxidized verapamil?

product ion

0

1

2

4

7

9

11 14 17 22 25 28 30

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Kümmerer et al., submitted

01000000

K. Kümmerer
16

day

60
3000000

100

90

80

70

50
4000000

2000000

40

500000030

20

107000000
600000008000000

DOC

16.5

16.9

17.4

19

Retention time

Transformation Products ofPiperacilin (HPLC-UV/Vis)

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Trautwein & Kümmerer, submitted

product ion

dead end transformation productday 30Elimination of Verapamil in the ZWT(LC-MS/MS)

Peak Area (rel. Units)

Primary Elimination of Verapamil in
the ZWT (LC-MS/MS)

Elimination DOC [%]- 403 -

O

H
N

O

HN

N

H

O

S

OH

+H2O

0.0

0.5

1.0

1.5

2.0

2.5

O

N

m/z=536
m/z
537

N

SC

K. Kümmerer
19

Sample
Probe

0




5




 ANOVA mit Dunnett's Post-hoc-Test,
p < 0,05 - 0,01

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Corrected
Korrigierteabsorption
Absorption (Mw ± SD)

O

O
H
N

O

O

HN

OH

H

N
H

S

O

15



Decreasing Estrogenic Activity
by Advanced Oxidation

K. Kümmerer
17

confirmed by LC-MS/MSO

Kümmerer et al., submittedNO

m/z 519m/z=518

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11thNO

Hydrolysis of Piperacilin LC-MS/MS

OH

N

M=376

O

O

O
H
N

O

O

HN

O

OH

M=159

O

O

H
N

O

HN

S

N
H

M=491

N

M=491

N

O

O

N

N

O

O

O

O

bacteria

OH

H

O

H
N

H
N

Bakterielle Umsetzung

-CO2

O

M=536

K. Kümmerer
18

N

O

HN

O

HN

O

O

OH

OH

H

H

N
H

S

N
H

S

OH

detected by
LC-MS/MS

M=393

O

M=349

SC

K. Kümmerer
20

SampleProbe0 ANOVA mit Dunnett's
Post-hoc-Test, p < 0,01

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

5



15



Increasing Androgenic Activity
by Advanced Oxidation

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

N

S

OH

N

Decarboxylation of Piperacilin
LC-MS/MS

Kümmerer et al., in preparation

N

Corrected
Korrigierteabsorption
Absorption (Mw ± SD)- 404 -

- 405 -K. Kümmerer
21

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th• Reaction by-products?

K. Kümmerer
23• Infiltration of the ground before STP?

• Storm water?

• Costs?

• Antibiotics: Resistance and bio-membrane (enrichment,
residence time)• Efficiency may depend strongly on the type of compound.

• Advanced filtration technologies (reversed osmosis,
membrane filtration, nanofiltration), and (photo)oxidation
technologies are emerging.

Advanced Effluent Treatment (1)10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Which compound to what degree!

Elimination?

1
2

3

4
Slow sandfiltration

4

Effluent:“without”
trace
contaminants

Other advanced
reatment

5

K. Kümmerer
22

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

K. Kümmerer
24• Not compatible with green chemistry.

• Not possible in less developed countries• Effective for new compounds?

Advanced Effluent Treatment (2)10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th• Adsorption (coal)• Membrane (bio-, membrane filtration, ultra-filtration, …)• Advanced Oxidation (ozone, fenton-, photo-, …)• Slow sand filtration

Influent:
sewagewith tracecontaminants„classical treatment“

Advanced Effluent Treatment- the Solution?

N
H

F

F

HO

5-FU

ZWT 28 days

CBT 45 days

CBT 28 daysN
H

O

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

-10

10

30

50

70

90

O

O

HN

HN C

C

O

OH

O

F

F
H

N

K. Kümmerer
27

Gemcitabin

Log P: -0,9Henry's Law: 13,56

C9H11F2N3O4
Mol. Wt.: 263,2

H

H

O

N

NH2

HO

OH

O

Cytarabin

H

H

O

N

H

OH
H

N

NH2

Kümmerer & Ahmad,
Acta Hydrochim.
Hydrobiol., 25, 166-172
1997

of Structurally Related Cytotoxics

Different Biodegradability

Na+

O-

K. Kümmerer
26

O

S

O-

Na+

O

ß-D-Glc-IPM („Glufosfamide“)

Ifosfamide:
not biodegradable (0%)

P

K. Kümmerer
28

well biodegradable (< 70%), improved
resorption in the gut; clinical trial phase III
10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11thCl

Kümmerer et al. Chemosphere, 40, 767 (2000)

ClCl

keeping the active moiety

PCl

Improving Biodegradability:
The Cytotoxics Ifosfamide and Glufosfamide

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

HO

OH
OH

K. Kümmerer
25

LAS: readily biodegradable

O

HO

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

SO

New legislation for surfactants 1962

TPS: not biodegradable

O

O

1955

O

Improving Biodegradability:
Surfactants

NH

NH

O

Not Biodegradable TPS …

N

O

Biodgradation in %NH

- 406 -

- 407 -K. Kümmerer
29

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

K. Kümmerer
31

Freiburg im Breisgau

Thank you!

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Kümmerer, Green Chemistry, submitted; www.start-project.de

identification (sub)structures essential for• efficacy• (bio)degradability

readily degradable in the environment

New compounds are effective, efficient, andLong Term Risk Management:
Green Chemistry & Pharmacy

K. Kümmerer
30

See also: Daughton C. G. (2003): Cradle-to-Cradle Stewardship of Drugs for Minimizing
Their Environmental Disposition While Promoting Human Health. I. Rationale for andAvenues toward a Green Pharmacy. Environ. Health Perspect. 111, 757•

10th Japanese-German Workshop on Water
Technology, Berlin, October 8th-11th

Big Green Chemistry initiative by the U.S. Environmental
Protection Agency

In the middle and in the long run there will be an increase ofinnovation and economical advantages for healthy andenvironmental friendly products. (German Advisory Board
for Environment 2003)••… within a generation chemicals should be produced andapplied that do not have any impact on the environment.
(EU Parliament and EU-Commission 2002)•

Economical and Other Aspects───────────────────────

国土技術政策総合研究所資料
Technical Note of NILIM
No. 360
February 2007
土 木 研 究 所 資 料Technical Note of PWRI
No. 4040
February 2007
編集・発行

© 国土技術政策総合研究所© 独立行政法人土木研究所

───────────────────────

本資料の転載・複写の問い合わせは
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独立行政法人土木研究所 企画部 業務課〒305-8516 茨城県つくば市南原 1‐6 電話 029-879-6754