Facility Map

Sanyo Main Line

Nishi-Takaya Station

Saijo Station

Shiroishi Station

Takaya JCT
Higashi HiroshimaKure Expressway

Hiroshima Chuo Ecopark
National highway

375
ROUTE

Sanyo Expressway

Sanyo Shinkansen

National highway

2

ROUTE

National highway

2

ROUTE

National highway

375
ROUTE

National highway

375
ROUTE

Higashi Hiroshima
Station

Saony

Snhi

ka

ns

en

Kamiminaga
Nishi

Kamiminaga IC

HIROSHIMA CHUO ECO PARKNSludge Recycling Processing Center
Nobinobi Square
Vehicle Washing
Building
Slag Stockyard
Building

Citizens’ Exchange Cafe

Sludge RecyclingProcessing
CenterHigh-Efficiency
Garbage Power
Generation FacilityAdministration
Building
Measurements Eco Square Connecting Passage
Eco Square BuildingConnecting Passage

Eco Square Observation Building

Eco SquareNFoot BathHIROSHIMA CHUO ECO PARK 10759-2 Kamiminaga, Saijo-cho, Higashi Hiroshima, Hiroshima 739-0022
Tel. 082-426-0820 / Fax. 082-426-0674

Business operator

Hiroshima Chuo Environmental Sanitation Association
10759-2 Kamiminaga, Saijo-cho, Higashi Hiroshima, Hiroshima 739-0022
Tel. 082-426-0820 / Fax. 082-426-0674

Design/construction administration

Design/construction

Eight-Japan Engineering Consultants Inc.
Hiroshima BranchHitachi Zosen Corporation
Chugoku Branch

Hiroshima Chuo Environmental
Sanitation Association

■ A facility to be a base for environmental study

Realizing Towns that Can be Lived in Comfortably:
Welcome to Hiroshima Chuo Ecopark

This is the visitors’ passage circling from the High-Efficiency Garbage Power Generation Facility to the Sludge Recycling Processing Center.
We provide plenty of hands-on study and tour programs for visitors to understand energy made from waste and the mechanisms that create
combustion aids from night soil.

Sludge Recycling Processing Center

Hiroshima Chuo Ecopark’s Sludge Recycling Processing Center is a facility that treats night soil andHigh-Efficiency Garbage Power Generation Facility

septic tank sludge from Higashi Hiroshima and Takehara. We strive to be a base for an advanced

Steam turbine andgenerator roommaterial-cycle society by building a zero reclamation system.

Treatment equipment room

43

Administration Building
1 Garbage receiving zone
2 Melting/thermal recycling zone
3 Flue gas processing zone

Clean, processedwater

A facility to bea base forenvironmental
study

Recycleinitiatives

Environmentallyfriendly facilities

6Operationalmanagement
through centrally
focused observation

Centralobservation
room
Waterquality
laboratory

4 Recycle zone

5Conference Connecting
Passageroom
Electricroom

5 Facility introduction/preliminary explanation zone
Furnace room

Electricroom

9 Quiz zone
10 Work zone

7Waste pit (collection)

89

After 300kL per day of night soil and septic tank sludge are dehydration separated, treatment to separate organic matter and nitrogen using
microorganisms is conducted, and the treated water is discharged into the sewer.

10Effluent quality
Hydrogen ion concentration (pH)Night soil/septic tank sludge

Separated water

Effluent

5.8-8.6

Biochemical oxygen demand (BOD)

20mg/L or less

Chemical oxygen demand (COD)

150mg/L or less

Amount of suspended solids (SS)

70mg/L or lessTotal nitrogen (T-N)

30mg/L or lessTotal phosphorous (T-P)

5mg/L or less

■ Recycle initiatives

7 Natural energy zone
8 Biological treatment/discharge zone

2Solar panel■ Clean, processed water

6 Receiving/dehydration zone

Receiving room

Waste pit (receiving)Mainconferenceroom
Connecting
Passage

NPlatform

1SConnecting Passage■ Environmentally friendly facilities■ Operational management through centrally focused observation

The water testing laboratory analyzes water quality for each piece ofequipment and checks whether water is being treated stably. Odor
countermeasures are also thorough, such as the adoption of a deodorization
system combining high-performance methods for biological deodorization,
chemical cleaning, and activated charcoal absorption.

The central observation room conducts focused observation of all
facilities. The status of all equipment is indicated on the monitoring
screen, and conditions such as operation of all equipment can bemonitored.

Water testing laboratory

Central observation room

Impure components in night soil and septic tank sludge are dehydrated by the sludge dehydrator to a moisture content of 70 percent or less.
Dehydration allows this material to be utilized efficiently as a combustion aid at the High-Efficiency Garbage Power Generation Facility.

How the sludge dehydrator works
Impure components in night soil and septic tank sludge are compressed and removed with a screw impeller then separated into dehydration-separated
liquid and combustion improvers using an external cylinder metal filter.

Night soil/septic tank sludge + Chemicals
Compression
cylinderFacility OutlineActuator
ScrewSludge dehydrator

Business operator

Hiroshima Chuo Environmental Sanitation Association

Consisting cities and towns

Higashi Hiroshima/Takehara/Osakikamijima

Facility name

Sludge Recycling Processing Center, Hiroshima Chuo Ecopark

Location

10759-2 Kamiminaga, Saijo-cho, Higashi Hiroshima, Hiroshima

Materials processedNight soil/septic tank sludge/agricultural community waste water sludge

Processing capacity

300kL/day
Night soil: 53kL/day, septic tank sludge: 247kL/day

Processing method

Water-treatment facilities: denitrification treatment methodwith a high mixture ratio of septic tank sludge + effluent sewerage

Separated water
To the storage tankCombustion improver1

Efficient utilization at the High-Efficiency
Garbage Power Generation Facility

Reuse facilities: sludge combustion-improving method
Lot size

191,993.70m2

Total floor space

21,891.07m2

Design/construction

March 30, 2017-September 30, 2021

2

Treatment Procedure
Receiving and retaining facility

Pre-flocculation separation (reuse) facility
8

Dehydration aid I (inorganic)

8

Dehydration auxiliary agentDehydration aid II (organic)

AcidB

B

Sludge reaction tankRe-aerator blower

4 Sludge dehydrator

2 Receiving room

MM
Night soil/septic tank sludge

PSludge supply
pump

Sludge supplytank

Grit tankP

Receiving tank

PP

3

Relay tankagitation pump

Crushing
pump

Denitrification tankagitation device

Separated water

Concentrator

Relay tank air
agitation facility

Grit

Principal treatment facilities

MB

1 Truck scale

7

Relay tank

PP

Storage tankagitationpump

Storage tankinsertionpump

Storage tank

888Methanol

Antifoam agentMethanol

Flocculation agent(inorganic)

Alkali

M

Night soil/septic tank sludge

Combustion improver

Cleaning tank
B

Combustion-improverremoving facility

5 Combustion

Grit blower

improverretainingfacility

Denitrification tank

Nitrification tank

Secondary denitrification tankRe-aerator tank

Settling tank
ReturnP

P sludge

Circulating fluid transport pumppump

Return sludge

Grit container

6 Arm roll truck

To the High-Efficiency Garbage Power Generation Facility

To the High-Efficiency Garbage Power Generation Facility
Waste sludge

Recycled water

Medium concentration odor

Miscellaneousdrainage transportpumpFFPMiscellaneous
drainage tank

12High concentration
odor capturing fan88

High concentration odor

AlkaliAcid

9Water supply from the High-Efficiency
Garbage Power Generation Facility

Biologicaldeodorization
towerMedium
concentration
odor capturing fan

Hypochlorite

PP

Acid
circulationpump

10 Acid/alkali

hypochlorite
cleansing tower

Sand filtration tower

Fume stack
Treated water
Treated water

11 Activated charcoal

absorption tower forintermediateconcentration

From the HighEfficiency Garbage Power
Generation Facility
Water quality
monitoring facility

Alkali/hypochlorite
circulating pump

Septic tank treated water

Deodorized drainage
Process water

Water for domestic use

Samplingpump

Low-concentration odorPF

Low-concentrationodor-capturing fan
PProcessirrigation watersupply facility

P

Water
receiving tankF

Receiving roomodor-capturing fan

Clean watersupply facility

Water intake and drainage facility
3

Receiving room odor

Deodorizing facility

8P

Activated charcoal
absorption tower for
low concentration

PP

Recycling
Filtrated water tank
water
pump

Sand filter
pump

Effluent tank

Hypochlorite

Discharge
pumpSewer

Effluent sewerage facility4Main Facilities
Receiving and retaining facility
Night soil and septic tank sludge are inserted from an outlet in the receiving room and transported to the relay tank via the crushingpump after sand and gravel are sedimented and separated.

Principal treatment facilities

Chemical injection facility

Dehydration-separated liquids are treated using microorganisms until contaminants
such as BOD and nitrogen-containing substances in the dehydrated filtrate are ofeffluent quality.

Chemicals used in the facility are sent to all equipment via aninjection pump.

Mockup1 Truck scale2 Receiving room

3 Crushing pumpPre-flocculation separation (reuse) facility
Post-crushing-treatment night soil and septic tank sludge pass from the relay tank through the sludge supply tank to be sent to the sludge reaction tank, where they are mixed with chemicals.
After that, sludge quantity is reduced and turned into a combustion improver by being dehydrated to the required combustion-improver moisture content of 70 percent or less in thesludge dehydrator.
Dehydration-separated liquids are sent to the principal treatment facilities, and the combustion aid is utilized efficiently at the High-Efficiency Garbage Power Generation Facility.

7 Treatment equipment room

8 Chemical injection facility

Microorganisms

Deodorizing facility
Biological deodorization using microorganisms is conducted for highly concentrated odors generated by equipment including the receiving tank, relay tank, and sludge dehydrator.
These are then merged with intermediately concentrated odors generated by the principal treatment facilities and treated using chemicals in the acid/alkali hypochlorite cleansing
tower. Finally, deodorization is carried out in the activated charcoal absorption tower for intermediate concentration. These odors are captured as low-concentration odors in rooms
such as the receiving room and deodorized by the activated charcoal absorption tower for low concentration.

4 Sludge dehydrator

5 Combustion improver retaining facility
5

6 Arm roll truck

9 Biological deodorization tower

10 Acid/alkali hypochlorite cleansing tower

11 Activated charcoal absorption tower for intermediate concentration

12 Fume stack
6