Economical development

Transcription

1 Ken Fukushi, Ph.D. Associate Professor of Integrated Research System for Sustainability Science The University of Tokyo, Japan 1

2 Economical development Income increase High energy consumption High material consumption Lifestyle change Diet change Etc. Urbanization High-rise buildings Heavy traffic and highway Dense population Waste Production Water consumption Traffic accident Air pollution and traffic jam Energy shortage Good job opportunities and higher income Housing problems Large energy, material, goods, and water demandurban-rural problem 2

3 Rapid development of urban area Increase commercial and domestic water use Increase of population Increase domestic water use Change of lifestyle Increase domestic water use per capita (300 liter/p) Inadequate wastewater treatment Deterioration of water environment Small amount of water recharge to groundwater Urban inundation and groundwater table decrease Overuse of groundwater Groundwater table decrease and ground subsidence Stealing water and illegal use of water 3

4 Annual rainfall and water availability Annual rainfall (mm year -1 ) per capita (m 3 year -1 capita -1 ) Canada New Zealand Sweden Australia Indonesia USA WORLD Austria Switzerland The Philippines JAPAN France Spain Italy China Iran India Thailand Romania UK Annual rainfall per capita Available water resource per capita Modified from the source: Japan International Cooperate Agency 4

5 Urban population year 5

6 China China India India 6 6 Population, 100 million

7 7

8 Population (million) Population with water supply/sewerage in Tokyo Population with water supply 95.9 % 98.0 % Population with sewerage Total Population Financial year Figure created by Dr. S.Ishii, COE Project, Tokyo University Created from the sources: Bureau of Waterworks, TMG; Keihin Office of River, MILT Japan; Bureau of General Affairs, TMG 8

9 Large share of treated water in rivers Purify 1000 liter Shishigebashi of wastewater bridge. = approx 0.5 liter of crude 50.6% oil = approx 0.2 kg of CO2 Kodairabashi bridge 50.2% 95.9% Yanagibashi bridge Shingashi riv. Treating wastewater 2% of total electricity demand of Japan Sumidagawa riv. Nakagawa riv. 17.0% Tamagawa riv. Tamakawara bridge Ryogoku bridge 18.1% 71.0% 35.3% Kasaikobashi bridge Chofu intake gate 32.3% Treated water (%) Taishibashi bridge 0 km 5 km 10 km 20 km Tamagawa River, Picture source: Keihin office of river 9 Source: Bureau of Sewerage, TMG

10 Rainwater and miscellaneous-use water reuse National Sport Stadium Daily use: 20.9 m 3 (70% of total) Tank capacity: 1,000 m 3 For toilet flushing and cooling water Tokyo Dome Stadium Daily use: m 3 Tank capacity: 1,000 m 3 For toilet flushing only Sinjuku sub-centre Daily use: 2,740 m 3 (30% of total) Tank Capacity: 8,000 m 3 For toilet flushing only 10 Source: Bureau of Urban Development, TMG

11 Restoration of natural ecosystems and aquatic amenity Nobidome yousui Senkawa jyosui Tamagawa jyosui Dry up Picture source: Bureau of Sewerage, TMG Picture source: Mitaka Education Centre 11

12 Ochanomizu station Kandagawa riv. Picture source: Tokyo Canal Project Sumidagawa riv. Picture source: Tokyo Canal Project Nihonbashi 12 Picture source: Tokyo Canal Project

13 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 Proposal of decentralize water management system 13

14 Advantages Easy for water reuse No need for pipeline to deliver wastewater Easy for groundwater recharge Relatively small investment for each unit Disadvantages Difficult to reuse water Need a small-footprint, high efficiency, easy maintenance process Maintenance problem Big investment 14

15 City Country Coverage (%) Tokyo Japan 99.9 Sendai Japan 97.2 Bangalore India 53% Karachi Pakistan 33% Dhaka Bangladesh 21% Manila Philippines 11% 15

16 Decentralized water system: example of single unit Single house ~ large community Water purification Water supply Wastewater Water reuse Non-permeable layer (pavement, buildings etc) Rain fall Wastewater treatment Energy Water use Groundwater Water recharge MBR: Membrane bioreactor 16

17 Utilizing sewer and water supply systems Use groundwater as a stock Community can decide treatment method Water Management Unit River Lake 17

18 Water Management Unit Community-based management Utilizing natural system River pond Lake 18

19 Decentralized water management system (ultimate status) Urban Heat Control Groundwater utilization Restoration of of river Risk management Better storm water ctrl Heat management Rain Water treatment purification purification River/lake recharge Water system recharge recharge groundwater groundwater Urban water stock Groundwater flow analysis 19 19

20 Treating wastewater to produce extremely clean water for groundwater recharge Treating groundwater to produce drinkable-quality water Requirements for the technology Easy to maintain Low capital cost Safety of treated water Membrane technology 20

21 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 Purified water Raw water21

22 Nanofiltration Membrane Reverse Osmosis NF RO Ultrafiltration UF Microfiltration MF Size ( m) Relative Size of Common Materials Application Cl - ion Na + ion Sea Water Desalination Pesticide, Organic Material Influenza Virus Zn 2+ ion F - ion Virus Pb 2+ ion Polio Virus NO 3- ion Hepatitis A Virus Trihalomethane Brackish Water Desalination Less-fouling Drinking Water Drinking Water Algae, Mad Vibrio Cholerae Coliform Cryptosporidium Bacillus anthracis Wastewater Treatment Drinking Water 22

23 Membrane Bioreactor (MBR) technology (key technology) Conventional activated sludge system Prescreening Biological tank Effluent Sludge withdrawal Settling tank Side stream MBR (1 st generation) Membrane Submerged MBR (2 nd generation) Effluent Kazuo Yamamoto (1989) 23

24 Hydrogen car H2 fuel cell Water Reuse Utilization H2 Waste- water MBR Sludge Supercritical gasification Nutrients Use Can be small scale Can be small scale 24

25 Problem for for MBR Electricity for for operation and and maintenance Load Operation Maintenance Community service Commercial wastewater MBR (anaerobic) MBR (aerobic) Treated water Nutrients (N and P) MBR with Microbial Fuel Cell (MFC) reuse 25

26 Water Water stock Periurban area Vegetable production and other farming activities Leisure for urban people Outside of the region Crop desalination Water stock Urban area Commercial activities Energy Production GW Stock Water stock Natural beauty Water Nutrient subsidy Water stock Safer products Agricultural products Sea $ for higher price products Water stock Energy 26

27 Decentralized water management system (combined with water reuse system) potentially attractive for developing Asian cities Asian cities need to develop new type of relationship with rural area Development needs time. However, we experience it much faster than western countries. 27

28 Thank you Special Thanks to: Dr. Tran Thi Viet Nga Dr. Ryo Honda Dr. Kazuo Yamamoto Sustainable Urban Regeneration Project Toray Co. Ltd. BOD 25 mg/l Ken Fukushi 28