Maintenance of Sewage Treatment Plant/Wastewater
Treatment Plant and Installation of IoT (Internet of Things)
and Liquid Film Aeration System in Bali, Indonesia
AKHMAD RIVAI (アハマド リパイ）
PT. Earth Creative Indonesia (株式会社アースクリエイティブ)
August 2023

３Project Overview Implementation• Technology Provision• Maintenance Manual Support• Local Seminar Support• Investment• Technical Support• Human Resource

Business Implementation
Partnership
Johkasou Maker

University

Local Corporation
ウダヤナ大学

Desludging
Company

Local Government

Regarding domestic wastewater treatment facilities
Provision of proper management technology(Facility maintenance,improvement consulting)sewage treatment plant
Established institution
HotelRestaurant• Local seminar

Bali Province

Badung Regency

Research andDevelopment

Hospital

Public Institution
SchoolHousing Complex

1

2

Situation and Issues in The Project Implementation Area
Current Status of Domestic Wastewater Treatment in Indonesia and Bali Province(1) Deterioration of water quality in public water areas due to population and tourist increases• In Bali, the deterioration of water quality in public water bodies (rivers and surrounding waters) is accelerating due to the increase in population andtourists. Denpasar, the provincial capital, has shown an increase rate of more than 10% in five years, and the adjacent Badung Regency has many
world-famous tourist destinations, attracting 5 million foreign tourists annually (Indonesia). Approximately 41.6% of all foreign visitors in 2019).
• In Denpasar City, sewerage development is underway in three districts, but despite the fact that the installation area is still limited, wastewater thathas already exceeded the treatment capacity of the sewage treatment plant is flowing into it. Therefore, it is still important to carry out appropriate
treatment at the place of wastewater generation.
• Since hotels for tourists generate a large amount of wastewater per day, they have installed their own wastewater treatment facilities such as septictanks. However, due to lack of proper maintenance and lack of appropriate management, untreated wastewater is often discharged.

(2) Measures taken by government agencies to improve water quality• In Bali, natural landscapes such as beaches are major tourism resources, so improving the water quality environment is the mostimportant issue for administrative agencies. Each state has its own effluent standards that are stricter than the national standards.
• Medium- and large-scale commercial facilities such as hotels are obliged to submit water quality analysis results by a specialized
inspection agency once a month, and facilities that do not meet the wastewater standards are subject to administrative sanctions suchas improvement orders and discharge ban.

23Progress of Feasibility Study Activities Related to The Installation of a Liquid Film
Aeration System and IoT Monitoring Sensors

 Overview of technologies currently planned for introduction
Technique

1. Liquid film Aeration System

2. IoT Surveillance Sensor

Features

Improvement of processing capacity by increasing DO value / Reduct
ion of electricity consumption / Easy installation to existing facilities/ Low cost introduction by local optimization

24-hour online monitoring/Low cost of installation and operation due to local optimization/Easy to change specifications/Easy to install in ex
isting facilities

Liquid film
aeration system

Forms a liquid film (water bubbles) on
the water surface
By increasing the number of bubbles on thewater surface, oxygen supply from theatmosphere increases in addition to oxygen
supply from inside the bubbles.

Water Quality
SensorMounting part

Water Quality
Sensor Controller

Field Communication
DeviceInstallation situation

Improved oxygen dissolution efficiency
水の薄膜（液膜）

O2

TechnicalDetails

大気（O2）液膜

水Air エアストーン
Diffuser

水Blower
エアポンプ

Data that can be confirmed on the cloud (specs may change)

Liquid film aeration system and operating conditions (example in Thailand)

Examples of adaptation to similar projects
Liquid film aeration system: (1) Demonstration project at a sewage treatment facility (FY2008-FY2010 Ube City, Yamaguchi Prefecture, Sewage Works Agencycommissioned project)
(2) Application of liquid film oxygen supply method to shrimp ponds in Thailand (FY2011-2013 Mitsui & Co., Ltd. Environment Fund grant research)
IoT monitoring sensor: Utilizing the Yamaguchi Prefecture support subsidy in 2018, prototype manufacturing has been completed and is in the testing stage
Maintenance service: Business feasibility study of maintenance service in Badung Province in JICA commissioned project "Water environment improvement project
feasibility study by building a comprehensive maintenance and management system for septic tanks in Bali, Indonesia (2017-2018)"

34

Installation of Liquid Film Aeration System in Ayana Resort
Effect test results of the liquid film aeration system on-site this fiscal yearAt the Ayana Resort & Spa Hotel (hereinafter referred to as Ayana Hotel), we installed 3-series and 5-series liquid film units in an
aeration tank and conducted a demonstration experiment. We collected basic information for the long-term demonstration test nextyear.

Only the liquid film unit part was brought in from Japan, and the blowers and pipes were procured locally, and two sets of 3 units
and 2 sets of 5 units were put into the aeration tank. (I changed the set in the middle to see the effect of unit size.)

The table below shows the results of blowing air by directly connecting existing 200W and 240W blowers to each device. (See thenext page for the detailed layout and flow of treated water.)

Change in DO value due to the introduction of a liquid membrane device
February 8, 2020 Installed
2 units of triple liquid
membraneFebruary 12, 2020 Replacedwith 2 units of 5 consecutive
liquid membranes

March 2, 2020
Switched to AS-25 (no liquid filmunit: control experiment)

Before introduction: DO from1.7mg/L(4 days later)
2/12 DO increased to 3.1mg/L

From 2/12 DO 3.1mg/L(7 days later)2/19 DO increased to 4.4mg/L

From 3/2 DO 5.2mg/L(2 days later)
3/4 DO decreased to 3.9mg/L

Set of 5-unit and 3-unit

Changing to a 5-consecutive liquid membrane device

The effect of theliquid film
aeration system
was confirmed.

ＡＳ-254

5FS Survey Results Liquid Film Aeration SystemEffect test result of liquid film aeration system on site

Drainage
Flow

Aeration tank 1

Aeration tank 2

Depth 4.0m

Depth 4.0m

13.57ｍInstallation location

Liquid Film Aerator(The photo shows a5-tube type)

Aeration tank capacity
169.3ｍ3×2＝
338.6ｍ3
Installation location

DO Value
Measurement PointIn

3.12ｍ

3.12ｍ

Out5Installation of IoT System in Earth Creath, Japan
Examples of applying IoT sensors to similar projects•

Equipment Appearance and Installation Status

Installation results at Earth Creative Co., Ltd.

Real-time monitoring screen (2020.2)•Adding an automatic email sending function when an error occurs•Expected to be introduced locally (Ayana Hotel) (scheduled for May 2020: as soon as thewireless usage permission (3G) under the Radio Law is obtained)
667

Demonstration of Liquid Film Aeration System
Wastewater treatment septic tank facility at Udayana UniversityHospital
A: Inlet
B: Equalization
C: Aeration 1
D: Aeration 2
E: Clarifier 1
F: Effluent 1
G: Effluent 2
H: Clear Water

Aeration unit D point

IoT sensor D point

depth
2000ｃｍAeration Tank

IoT sensor
Point H

Liquid film aeration unit
5-station typeInstallation location: C, D

OutletWater samplingpoint

IoT sensorPoint Ainlet

aeration unit
Point C

Water sampling
schedule(During projectperiod)
Influent (A) Total 3times
Discharged water (H)Total 3 times

IoT sensor installation point
IoT sensor
D: pH water temperature DO
A&H: pH water temperature

Sewage treatment flow

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8

Water Quality Test•••

Water quality inspection items are measured simultaneously for Indonesianstandards (including special standards for Bali) and for verification surveys.
(DO values are measured voluntarily since there is no standard in Bali)
After the current situation survey, we plan to measure the same items
throughout the implementation period including after the liquid film aeration
system is installed.
The measurement period is from August 2020 to March 2022 (planned tocontinue thereafter)

検査項目
TSS
pH
NH3-N
BOD
COD
MBAS （表面活性剤）
油脂
DO

バリ州基準
50mg/L6~910mg/L

外部検査
IoT計測 仕様書
流入水 放流水
3回
✔
3回
3回
常時
✔
3回
3回
✔
3回
-

28mg/L

3回

3回

-

✔

50mg/L

3回

3回

-

✔

5mg/L

3回

3回

-

✔

10mg/L

3回

3回

-

✔

-

-

-

常時なし

8

18

Demonstration of IoT Sensors
 User interface on sensor monitoring software (web browser)

Basic screen
Because it uses a web browser, it can be checked
regardless of the OS (Windows, Apple, etc.), device PC,smartphone, tablet, etc.)

You can check the numerical value at the time the cursor is placed

The graph period can be freely selected.
As long as there is data on the server, you can go back to
the past and check the measurement values

It is also possible to select and change the desired period with the mouse
Selection state by dragging the mouse. When the mouse button isreleased as it is, this period is enlarged and displayed.

910Installation of IoT System in Bvlgari Resort
Arrangement of treatment tanks
4.55ｍ

8.1ｍ

3.55ｍ

4.15ｍ

4.15ｍ

Effluent
Tank

Irrigationtank

Liquid film aeration system and IoT monitoring system
Liquid film aeration system(Triple unit)

2.55ｍ

2.25ｍ

Maintenance MOU
3.31ｍ

Equalization
Tank

5.86ｍ

AerationTank

Sedimentation
Tank

3.3ｍ

2.55ｍ

8.1ｍ

3m deep for all tanks

IoT monitoring system

Location of liquid film aeration system
IoT sensor installation location

Installation of IoT monitoring system control panel

1011Installation of IoT System in Holiday Inn ResortBaruna
Connection between data transmitter and sensor controller

sensor controller

IoT sensor
Data transmitter
Sensor control unit and sensor connection/power supply connection

sensor body11

12

Installation of Iot System in FAME HotelIoT sensor platform
Old model
New model

Septic tank inunderground parking lot

IoT sensor base Improved waterproofness

Device damage due toflooding of undergroundparking lot due tounderground pump
failure12

20Dissemination and Development Seminar
告知リーフレット•Held online on February 7, 2022

• Seminar 59 participants

Presenter  Dr. I Nyoman Gede Antara (President, Udayana University)

Participant composition

Satisfaction with the seminar
OrdinaryPractitioners

 Hiroyasu Kawashima (Ministry of the Environment)

13%

4%

government

 Drs. Herry Hamdani (Ministry of Environment and Forestry,officialseminarIndonesia)

43%
Teacher15%

 Prof. Wayan Budiarsa Suyasa (Udayana University)

satisfiedstudent49%

 Kazumi Kurihara (PT. Earth Creative Indonesia, Earth Creative)

very

10%

satisfied53%

researcher
13% Tsuyoshi Imai (Yamaguchi University) Dr. Eng Ni Nyoman Pujianiki.(Udayana University) Akhmad Rivai (PT. Earth Creative Indonesia)

Prof. Dr. Ir. I Nyoman Gede Antara
By the President of Udayana
University
opening remarks

Mr. Kawashima, Ministry of theEnvironment
greeting

Prof. Wayan Budiarsa Suyasa
announcement

Professor
Takeshi Imaiannouncement

Earth Creative Indonesia
Greeting from President
Kurihara

earth creative indonesia
Akhmad Rivai

Question-and-answer
sessionCommemorative photoof participants(part)

13

Future Tasks
Technical Challenges
 Through this project, there were no major issues with the installation and durability of the liquid film
aeration system and IoT sensors. In the future, we plan to add a web camera function and improve thePC screen to make it easier to understand.

Policy Issues
 Although the national and state governments have developed laws and regulations such as standards
for the discharge of treated water, local governments at the prefecture level, which are directly
responsible for monitoring and inspection, are responsible for monitoring, inspection, and enforcementwith effectiveness and fairness. It is hard to say that there is a system that can do it. (Insufficienthuman resources, lack of individual knowledge, etc.)

Corporate Issues
 There are many people in charge who do not have knowledge of sewage treatment, such as the person
in charge of the entire facility who is not a specialist in purification facility management. Therefore,
countermeasures are ad hoc and do not improve even if costs are incurred. It is urgent and necessary
to develop human resources with qualifications like Japanese septic tank managers, but there is nosystem for doing so.
 Few maintenance workers have the knowledge and skills to solve problems.

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