Water Quality in a Changing Environment

Transcription

1 Water Quality in a Changing Environment Coalbed Methane (CBM) Produced Water K.J. Reddy Department of Renewable Resources School of Energy Resources University of Wyoming Arsenic Poisoning in Bangladesh

2 Water Quality in a Changing genvironment Energy egydemands Climate Change and Water Resources Climate Changeand and Surface Water Quality Clean Energy and Groundwater Quality Arsenic Case Study 1: Coalbed Methane Natural Gas (e.g., groundwater) Arsenic Case Study 2: Drinking Water (e.g., groundwater) Conclusions

3 Water Quality in a Changing Environment TW = Tera Watts =1x10 13 W World Energy Consumption

4 Anthropogenic Carbon Dioxide Atmospheric CO 2 (g) is essential for physical, chemical, and biological processes: atmosphere, hydrosphere, and geosphere of the Earth. Increase in anthropogenic CO 2 in atmosphere due to fossil fuel burning is raising concerns over climate change and global warming. Intergovernmental Panel on Climate Change (IPCC, 2007) reported atmospheric CO 2 (g) concentration in 2005 as 379 ppm compared to 280 ppm of preindustrial levels.

5 Water Quality in a Changing Environment NOAA (2007) predicted that increase in global temperature melt glaciers and change rainfall patterns significantly For example, south and western US could become more dry (drought) and generate unpredictable flood events, which degrade quality of surface water Examples: Himalayas, Andes (South America), Katrina (New Orleans)

6 Water Quality in a Changing Environment Himalayas: Mount Everest Glacier (Top 1921 and bottom 2007) lost 40% of ice (Frontline, PBS, October 21, 2008) Himalayan glaciers supply water to several major rivers in Asia (Indus, Ganges, Brahmaputra, Yellow, Yancy) and support billions of people (e.g., Nepal, Tibet, India, Bangladesh, China) Peru's glacier meltdown threatens water supplies, Science News:2007, (Mark and Mckenzie, ES&T)

7 Water Quality in a Changing Environment Arsenic in Hurricane Katrina wood debris, Science News: esthagw/2007/jan/science/ee_katrina.html Drive towards clean energy: Example natural gas (methane and coalbed methane), DOI: /es062504o Climate change increase our dependency on groundwater Exploration of clean energy sources (e.g., natural gas) increase our dependency on groundwater Arsenic Case Study 1: CBM (e.g., Clean Energy) and Arsenic Case Study 2: Drinking Water (e.g., lack of clean surface water) % Trends In Energy Consumption

8 CBM Exploration in US Wyoming: Total Recoverable CBM is (Tcf) (1.4years for US) Powder River Basin Green River Basin Wind River Basin Montana: Powder River Basin Colorado: Piceance Basin Raton Basin New Mexico: San Juan Basin Other Countries: Canada, China, India, Australia, New Zealand

9 CBM Extraction Process Typically 2 10 CBM wells are combined together to discharge produced water as a single point (outfall) A single CBM outfall in the PRB can discharge 8 80 L of produced water per minute The production of CBM produced water depends on the aquifer system and well density CBM Extraction Well

10 CBM Produced Water Channel Disposal Reinjection Pond Disposal Number of wells in production = ~16,000 wells; ~30,000 wells Total produced water expected = ~2 3 billion m 3 ; years Produced water management options = disposal ponds, reinjection, or stream channels Other Managementoptions = irrigation, aquaculture, livestock and wildlife watering

11 CBM Development North West of the PRB

12 CBM Development South of the PRB

13 Tongue River Powder River Little Powder River Powder River Basin, WY Cheyenne River

14 Water Quality Monitoring CBM water samples from each outfall and disposal pond were collected and monitored over a period of 8 years Outfall Disposal Pond

15 CBM Produced Water Quality ph CBM Produced Water ph and Oxidation/Reduction Potential by Watershed CHR BFR LPR PR TR Outfalll ph Pond ph Outfalll ORP Pond ORP ORP (m mv)

16 µg/l Outfall Arsenic Concentration in CBM Produced Waters CHR BFR LPR PR TR Disposal Pond

17 Arsenic Concentrations in CBM Produced Water Pond Sediments Water Soluble Fraction A mg Kg -1 [for Fe, Ba] A AB B B B µg Kg -1 [for As, Se] Fe Ba As Se Arsenic Video

18 Worldwide Occurrences of Arsenic in Groundwater Global Arsenic Concentrations in Groundwater [Nordstrom, Science (2002)] Country Concentration (ug/l) Source Bangladesh <1 to 2,500 Natural India <1 to 3,200 Natural Taiwan 10 to 1,820 Natural Vietnam 1 to 3,050 Natural Thailand 1 to >5,000 Mining Inner Mongolia <1 to 2,400 Natural Europe <1 to 176 Natural/Mining South America <1to 9, Natural/Mining North America <1 to 100,000 Natural/Mining

19 Countries Affected by Arsenic Poisoning oso 1A 1.America 2.Mexico 3.Chile 4.Bolivia 5.Argentina 6.Hungary 7.Romania 8.India 9.Bangladesh 10.Thailand 11.Vietnam 12.Taiwan 13.China 14.Nepal Adapted from Pearce, New Scientist 2003

20 Countries and Population Effected by Arsenic Poisoning i Bangladesh ~30 Million Nepal ~11 Million India ~6 Million South America ~2.8 8Million Vietnam ~1 Million Taiwan ~200,000 Mongolia ~600,000 Europe ~600,000 Thailand ~15,000 North America No Documented Cases harvard rsenic_project_introduction.html

21 Arsenic in Natural Waters Inorganic and organic forms Inorganic forms include arsenite (III) and arsenate (V) Arsenite is more toxic than arsenate to humans >10 ug/l of dissolved arsenic in drinking water causes health problems (US National Research Council, 2001): New Arsenic Legislation for Human Drinking Water (10 ug/l) Effective fromjanuary 23, 2006 (US EPA)

22 Current Methods to Remove Arsenic from Water Precipitation Process Adsorption Process Anionic Exchange Process Membrane Filtration Processes Require oxidation step Require ph adjustments Effected by other components of water Not suitable for small communities and produce waste byproducts

23 A Novel Method to Remove Arsenic from We discovered that laboratory prepared CuO particles can remove both arsenite and arsenate from water This reaction was never tested before to remove arsenic species from water (Reddy et al., 2007, 9 th ICOBTE) Unlike other arsenic removal methods, CuO particles require no oxidation step and ph adjustments or produces no harmful byproducts (US Patent NO: 7,235,179 B2, K.J. Reddy) Water

24 Groundwater Sampling for Arsenic Analysis MT ND SD NV WY UT NH CO NE

25 Arsenic in Groundwater Across US NV Samples BF AF 1= 56.8 =1.2 ppb 2= =2.0 ppb 3= =23 ppb 4= 398 = 20.9 ppb Drinking Water Limit Sample ID

26 Arsenic in Groundwater Across US Arsenic Concentration Before Reaction with CuO (ppb) Arsenic Con ncentration (pp pb) Drinking Water Limit Arsenic Concentration After Reaction with CuO (ppb) Sample ID

27 Dissemination of Findings Landowner Letters: Each year complete water quality data and other pertinent information mailed to each individual landowner (NH, NE, SD, ND, MT, CO, UT, NV, and WY) Share information with agencies (e.g., EPA and DEQ Wt Water Quality Division), Wyoming Geological Survey and U.S. Geological Survey National and International Conferences Published in appropriate extension bulletins and refereed journals

28 Conclusions Unpredictable flood events and drought due to changing environment degrade surface water quality, which forces us to depend don groundwater resources Drive towards clean energy source (e.g., Natural Gas, CBM) also require pumping of groundwater, which is unavoidable Exploitation of groundwater transport trace elements such as arsenic into ecosystem (drinking water, plants, animals, humans) To protect quality of natural waters (surface and groundwater) require innovative techniques which balance energy, environment and natural resources. Clean and Quality Water Healthy Families and Communities Socially and Economically Productive Nation