ken fukushi, ph.d. associate professor of integrated ... · pdf fileken fukushi, ph.d....
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Ken Fukushi, Ph.D.Associate Professor of Integrated Research System for
Sustainability ScienceThe University of Tokyo, Japan
Economical developmentIncome increase
High energy consumptionHigh material consumptionLifestyle changeDiet changeEtc.
UrbanizationHigh-rise buildingsHeavy traffic and highwayDense populationGood job opportunities and higher incomeLarge energy, material, goods, and water demand
2
Waste Production
Water consumption
Air pollution and traffic jam
Traffic accident
Energy shortage
Housing problems
Urban-rural problem
Rapid development of urban areaIncrease commercial and domestic water use
Increase of populationIncrease domestic water use
Change of lifestyleIncrease domestic water use per capita (300 liter/p)
Inadequate wastewater treatmentDeterioration of water environment
Small amount of water recharge to groundwater
Urban inundation and groundwater table decrease Overuse of groundwater
Groundwater table decrease and ground subsidenceStealing water and illegal use of water
3
4
Modified from the source: Japan International Cooperate Agency
CanadaNew Zealand
SwedenAustraliaIndonesia
USAWORLDAustria
SwitzerlandThe Philippines
JAPANFranceSpainItaly
ChinaIranIndia
ThailandRomania
UK
Annual rainfall (mm year-1) per capita (m3 year-1 capita-1)
Annual rainfall per capita
Available water resource per capita
Annual rainfall and water availability
0
10
20
30
40
50
60
70
80
90
1950 1975 2003 2030
WorldN. AmericaAsia
5
Urban population
％
year
66
0
1
2
3
4
5
6
7
8
9
2003 2030
China
China
India
India
Pop
ula
tion
, 100
mill
ion
7
8
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Population with water supply/sewerage in TokyoPo
pula
tion
(mill
ion)
Financial year
Total Population
Population with water supplyPopulation with sewerage
Figure created by Dr. S.Ishii, COE Project, Tokyo UniversityCreated from the sources: Bureau of Waterworks, TMG; Keihin Office of River, MILT Japan; Bureau of General Affairs, TMG
98.0 %95.9 %
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Tamagawa River, Picture source: Keihin office of river
Chofu intake gate
Yanagibashi bridge
Tamakawara bridge
Shingashi riv.
Shishigebashi bridge.
Tamagawa riv.
Kodairabashi bridge
Ryogoku bridge
Nakagawa riv.
Kasaikobashi bridge
Taishibashi bridge
71.0%
18.1%
32.3%
50.2%50.6%
95.9%
17.0%
35.3%
Source: Bureau of Sewerage, TMG
Sumidagawa riv.
Treated water (%)
Large share of treated water in rivers
0 km 5 km 10 km 20 km
Purify 1000 liter of wastewater= approx 0.5 liter of crude oil= approx 0.2 kg of CO2
Treating wastewater 2% of total electricity demand of Japan
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Rainwater and miscellaneous-use water reuse
Source: Bureau of Urban Development, TMG
National Sport Stadium
Tank capacity: 1,000 m3
For toilet flushing and cooling water
Daily use: 20.9 m3 (70% of total)
Tokyo Dome Stadium
Tank capacity: 1,000 m3
For toilet flushing only
Daily use: 186.3 m3
Sinjuku sub-centre
Daily use: 2,740 m3 (30% of total)
For toilet flushing only
Tank Capacity: 8,000 m3
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Restoration of natural ecosystems and aquatic amenity
Nobidome yousui
Tamagawa jyosui
Picture source: Mitaka Education Centre Picture source: Bureau of Sewerage, TMG
Senkawa jyosui
Dry upDry up
12Sumidagawa riv.
Ochanomizu station
Nihonbashi
Kandagawa riv.
Picture source: Tokyo Canal Project
Picture source: Tokyo Canal Project
Picture source: Tokyo Canal Project
“Developed countries apply energy-intensive technologies to keep urban water environment clean, however, such approach may not be appropriate for sustainable water environment management ” (modified from Wagner, Ohgaki and Zehnder et al. in Ambio)“Design, approval of the planning and the lay out of the piping and sewer networks is time consuming and swallows about 80% of the total investment costs”. (Peter Wilderer)“Estimating the cost of worldwide implementation of centralized system, it become evident that the capacity of global money market would not be sufficient to cover the need for investment capital”. (Peter Wilderer)
However, in old time, the centralized system is the only choice since treatment technology was not available in a small scale
13Proposal of decentralize water management systemProposal of decentralize water management system
AdvantagesEasy for water reuseNo need for pipeline to deliver wastewaterEasy for groundwater rechargeRelatively small investment for each unit
DisadvantagesDifficult to reuse waterNeed a small-footprint, high efficiency, easy maintenance processMaintenance problemBig investment
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CityCity CountryCountry Coverage (%)Coverage (%)
Tokyo Japan 99.9
Sendai Japan 97.2
Bangalore India 53%
Karachi Pakistan 33%
Dhaka Bangladesh 21%
Manila Philippines 11%
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Groundwater
Wastewatertreatment
Rain fall
EnergyWastewaterWater reuse
Water recharge
Water purification
Water use
Water supply
Decentralized water system: example of single unit
MBR: Membrane bioreactor
Non-permeable layer (pavement, buildings etc)
Single house ~ large
community
Single house ~ large
community
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River
Lake
Water Management Unit
• Utilizing sewer and water supply systems
• Use groundwater as a stock• Community can decide
treatment method
pond
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River
Lake
Water Management Unit
• Community-based management
• Utilizing natural system
1919
Rain
地下水涵養
Groundwater flow analysis
recharge
Water system
purification
Heat management
Urban water stock
Water treatment purification
rechargerecharge
groundwater groundwater
River/lake
Decentralized water management system(ultimate status)
• Urban Heat Control• Groundwater utilization• Restoration of river• Risk management• Better storm water ctrl
• Urban Heat Control• Groundwater utilization• Restoration of river• Risk management• Better storm water ctrl
Treating wastewater to produce extremely clean water for groundwater rechargeTreating groundwater to produce drinkable-quality water
Requirements for the technologyEasy to maintainLow capital costSafety of treated water
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Membrane technologyMembrane technology
21Raw water
Purified water
• Extremely high quality water
• Easy maintenance and easy mechanism
• Potential to be economical
• No need of high technology for module production (except RO)
• Extremely high quality water
• Easy maintenance and easy mechanism
• Potential to be economical
• No need of high technology for module production (except RO)
Raw water
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Membrane
Relative SizeofCommonMaterials
0.0001 0.001 0.01 0.1 1 10Size (μm)
Cl- ionNa+ion Pesticide, Organic Material
Zn2+ionF- ion
Pb2+ ionNO3
-ionTrihalomethane
Hepatitis A Virus
Polio VirusVirus
Influenza Virus Algae, Mad
Vibrio Cholerae
ColiformCryptosporidium
Bacillus anthracis
RO
NF
UFMF
Reverse Osmosis
Nanofiltration
MicrofiltrationUltrafiltration
Application
Sea Water Desalination
Less-fouling Drinking WaterDrinking Water
Wastewater TreatmentDrinking Water Brackish Water Desalination
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Membrane Bioreactor (MBR) technology (key technology)
Conventional activated sludge system
Side stream MBR (1st generation)
Submerged MBR (2nd generation)
Biological tank Settling tank
Effluent
Sludge withdrawal
Membrane
Effluent
Prescreening
Kazuo Yamamoto (1989)
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MBRMBR SludgeSludgeWasteWaste--waterwater
Supercritical Supercritical gasificationgasification
H2H2
NutrientsNutrients UseUseUse
UtilizationUtilization
Can be small scale
Can be Can be small scalesmall scale
Can be small scale
Can be Can be small scalesmall scale
H2 fuelcell
H2 fuelcell
Hydrogen car
Hydrogen car
Water Reuse
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MBR(anaerobic)
MBR (aerobic)
MBR with Microbial Fuel Cell (MFC)MBR with Microbial Fuel Cell (MFC)
wastewaterTreated water
Load
Nutrients (N and P)
• Operation• Maintenance• Community service• Commercial
reuse
• Problem for MBR•Electricity for operation
and maintenance
•Problem for MBR•Electricity for operation
and maintenance
26Sea
Periurban area• Vegetable production and other
farming activities• Leisure for urban people
WaterNutrient
Agricultural products
Water
Urban area•Commercial activities
subsidy
$ for higher price products
Natural beauty
Safer products
Crop
Energy
desalination
Water stock
Water stock
Water stock
Water stock
Water stock
EnergyProduction
GW StockGW Stock
Outside of the region
Decentralized water management system (combined with water reuse system) potentially attractive for developing Asian citiesAsian cities need to develop new type of relationship with rural areaDevelopment needs time. However, we experience it much faster than western countries.
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Thank you
Special Thanks to:Special Thanks to:Dr. Tran Thi Viet NgaDr. Tran Thi Viet NgaDr. Ryo HondaDr. Ryo HondaDr. Kazuo Yamamoto Dr. Kazuo Yamamoto Sustainable Urban Regeneration ProjectSustainable Urban Regeneration ProjectToray Co. Ltd.Toray Co. Ltd.
BOD 25 mg/lBOD 25 mg/l