Water Challenges - Past, Present, and Future. Perry L. McCarty Department of Civil and Environmental Engineering Stanford University

Transcription

1 Water Challenges - Past, Present, and Future Perry L. McCarty Department of Civil and Environmental Engineering Stanford University

2

3 Water Supply and Distribution Listed by the National Academy of Engineering as among the Greatest Engineering Achievements of the 20th Century

4 50 Years Ago - The arrival of new problems - bring a paradigm shift

5 Cuyahoga River, Cleveland, Ohio Burn on, Big River, Burn on Photographer - James Thomas

6 San Francisco Oil Spill National Geographic magazine photographs

7 Aerobic - Activated Sludge Treatment Toronto San Jose Chicago Los Angeles County

8 ABS Synthetic Detergents 1950s Photographer - Bruce M. Wyckoff

9

10 Whittier Narrows, CA 1962 Wastewater Reuse

11 1962

12 South Lake Tahoe Advanced Wastewater Treatment

13 Direct Potable Reuse, Windhoek, Namibia

14 Orange County, California Water Factory 21

15 Super Fund

16 Global Annual Production of Synthetic Organic Material (Source UNEP, 1987) Million Tons per Year

17 Emerging Chemicals of Concern Perchlorate (ClO 4- ) Nitrosodimethylamine (NDMA) 1,4-Dioxane Fire retardants PBDE Perfluoros Pharmaceuticals Endocrine disrupters Fish Feminization

18 Worldwide Problem Over 1 billion people lack access to safe drinking water 2.4 billion lack access to adequate sanitation facilities In 1998, 2.2 million people estimated to have died of diarrheal diseases Millions suffer from parasitic worm infections

19

20

21

22

23

24 An Inconvenient Truth San Jose Mercury News April 3, 2007 New York Times April 3, 2007 Wall Street Journal April 3, 2007 Supreme Court ruled that carbon dioxide and other so-called greenhouse gases are air pollutants Wall Street Journal, April 3, 2007

25

26 Question What is impact of wastes and waste treatment on greenhouse gas emissions?

27 Global Warming Potential CO 2 = 1 Gas Carbon Dioxide (CO 2 ) Methane (CH 4 ) Nitrous Oxide (N 2 O) GWP

28 Global Anthropogenic Greenhouse Gas Emissions N 2 O 8% Other 1% CH 4 15% CO 2 76% US EPA, Global Mitigation of Non-CO2 Greenhouse Gases, June 2006, EPA

29 Anaerobic Pathways to Methane Formation Anaerobic Digestion, Elsevier (1981)

30 Anaerobic Treatment

31 Anaerobic Treatment in China

32 2000 Non-CO 2 Emissions - % of Total CO 2 eq 25 Percent Wastes Other Agriculture Enteric Ferment Rice Fossil Fuels World USA US EPA, Global Mitigation of Non-CO2 Greenhouse Gases, June 2006, EPA

33 2000 Waste CH 4 +N 2 O Emissions - % of Total CO 2 eq 5 Percent CH 4 N 2 O Waste- Water Manure Solid Wastes World USA US EPA, Global Mitigation of Non-CO2 Greenhouse Gases, June 2006, EPA

34 TUESDAY, NOVEMBER 6, 2007 SAN JOSE MERCURY NEWS SAN JOSE MERCURY NEWS TUESDAY, NOVEMBER 6, 2007

35

36 Water-Related Energy Consumption in California (2001) 35 % of CA Energy Usage Electricity Heating & Cooling End Use T & T Natural Gas California Energy Commission, CEC SF (2005)

37 kwh/million Gallons for Urban Water in California Supply & Convey Water Treatment Water Distribution Wastewater Treat. Total North ,200 2,500 3,950 South 8, ,200 2,500 12,700 California Energy Commission, CEC SF (2005)

38 Rene Dubois Think globally, act locally

39 U. S. Anthropogenic Greenhouse Gas Emissions Passenger Car 8.7% Source: US EPA, Inventory of U. S. Greenhouse Gas Emissions and Sinks: , Draft, February 20, 2007

40 Question How can we reduce energy consumption and greenhouse emissions from wastewater treatment?

41 2007 Google-Map Data NAVTEQTM

42

43 Palo Alto Wastewater Treatment Plant Primary settling Aerobic BOD removal Nitrification Sludge incineration

44 San Jose Wastewater Treatment Plant Primary settling Aerobic BOD removal Nitrification Sludge digestion

45

46

47 Sunnyvale WTP Stabilization Ponds

48

49 2007Google-Map Data NAVTEQTM

50 Primary Tanks 2007Google-Map Data NAVTEQ TM Influent

51 Stabilization Ponds Primary Tanks 2007Google-Map Data NAVTEQ TM Influent

52 Stabilization Ponds Flotation Primary Tanks 2007Google-Map Data NAVTEQ TM Influent

53 Stabilization Ponds Nitrification Flotation Primary Tanks 2007Google-Map Data NAVTEQ TM Influent

54 Stabilization Ponds Nitrification Flotation Filtration Primary Tanks 2007Google-Map Data NAVTEQ TM Influent

55 Stabilization Ponds Nitrification Flotation Disinfection Filtration Primary Tanks 2007Google-Map Data NAVTEQ TM Influent

56 Stabilization Ponds Nitrification Flotation Disinfection Effluent Filtration Primary Tanks 2007Google-Map Data NAVTEQ TM Influent

57 Digesters Primary Tanks 2007Google-Map Data NAVTEQ TM

58 Flotation Digesters Primary Tanks 2007Google-Map Data NAVTEQ TM

59 CO 2 + CH 4 Flotation Digesters Primary Tanks 2007Google-Map Data NAVTEQ TM

60 CO 2 + CH 4 Flotation Digesters Primary Tanks Drying Beds 2007Google-Map Data NAVTEQ TM

61 BOD Conversion to Algae Particulate C 5 H 7 O 2 N BOD 5O 2 5CO 2 + 2H 2 O+ Soluble NH 3 C 5 H 7 O 2 N

62 Cogeneration at Sunnyvale Wastewater Treatment Plant

63

64 CO 2 & N 2 O Release in Nitrification CO 2 Plus trace of N 2 O NH NaHCO 3 = Power Air NaNO 3 + 2H 2 O + CO 2

65 CO 2 Equivalents (1000 kg/day) Treatment of 10,000 kg BOD 5 /day BOD Removal CH 4 Oxidation CH 4 Loss (1%) Nitrification Energy Usage Total Aerobic + Incineration 3.6 Incineration 20.4 Digestion-CO Aerobic + Digestion (3.3) 12.2 Algae + Digestion (6.6) 6.2

66 Energy Costs - US$1000/year Treatment of 10,000 kg BOD 5 /day Aerobic + Incineration Aerobic + Digestion Algae + Digestion Oxygen Supply CO 2 Penalty Excess Power (299) (378) Total 236 (97) (366) CO 2 penalty = US$20/tonC

67 Water Reuse in Monterey County

68 Monterey Regional Water Pollution Control Agency Largest wastewater recycle in U.S. for irrigated crops Irrigates 12,000 acres 34.2 billion gallons produced since 1997

69 Water Reuse in Monterey County

70 Conclusions for Sustainability A reevaluation of waste treatment alternatives is needed because of climate change concerns Methane from wastes must be contained Desired alternatives are those that reduce both greenhouse gas emissions and power consumption Anaerobic treatment is likely to be an attractive component of the alternatives Wastewater is a resource for water, energy, and plant nutrients

71 Rene Dubois "Trend is not destiny"

72 Ancient Chinese Proverb "Unless we change our direction, we are likely to end up where we are headed"

73 Thank you!