Transcript Slide 1

Image found @ cleanocean.org
The environmental impact of
desalination waste disposal
Darren Kimple
Freshwater
Lots of people = lots of freshwater needed
By 2025: worldwide demand >
freshwater supply, by 56%
97% of water → in oceans
…let’s clean it up and use it
Desalination
• How does the process work?
• What happens to the waste?
• Effects on the environment?
• What problems have been caused?
Image found @ projects.gsd.harvard.edu
Desalination
Who can use it?
• Those with access to water sources
• Coastal areas
• Brackish aquifers
• Those who can afford it
• Oil-rich (water starved) Arabian Gulf countries
• Other wealthy countries like the U.S.
How does the desalination
process work?
Image found @ wwn-online.com/articles/69197/
Image found @ coal2nuclear.com
Waste Disposal
45% → surface waters
25% → publicly owned treatment works
15% → deep well injection
Remainder → evaporation ponds and other
land applications
Desalination Waste
What’s in it?
Lots of salt (up to 2.5X more than
seawater)
Chemicals and metals used to initially purify water at intake
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Heat
biocides
anticorrosion chemicals
coagulants
corrosion metals
Deep Well Injection
Environmental concerns:
• A leak in the aquifer could cause
contamination to freshwater supplies
• Earthquakes
• Increase in fluid pressure
• Has caused several thousand
small earthquakes in the
Colorado Rockies
Image found @ www.simsenv.com
Landfill and Evaporation Ponds
Environmental concerns:
• Groundwater contamination
• Waste infiltration into subsurface
• Possible effects on drinking water
• Animals and their habitats
• Harmful chemicals in waste
• Vast space required
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River and Sewer (publicly owned
treatment works)
Environmental concerns:
• Contamination of streams
• Fish habitats
• Human resources
• Overload on local water treatment plants
Image found @ www.thameswater.co.uk
Solutions
• Dilution of discharge with power plant
cooling water
• Cools down outgoing water
• Possible only where desalination plant is near power plant
• Separation of harmful constituents before
discharge to water body
• U.S. facilities are required to aerate and adjust pH on
discharging concentrate
• Filtered chemicals can later be reused
• Monitoring
Effects of Direct Ocean Discharge
Negative effects:
• Southern Australia
– High salinity levels
– 50% mortality rate for certain organisms
• Sea urchins
• Starfish
Image found @www.yannarthusbertrand2.org
Effects of Direct Ocean Discharge
Negative effects:
• Kuwait Bay:
– Toxic chlorine concentrations
• Phytoplankton
• Vertebrates and invertebrates
– Dumped daily into the Red Sea:
• 2,708 kg of chlorine
• 36 kg of copper
• 9,478 kg of antiscalants
Image found @www.yannarthusbertrand2.org
Effects of Direct Ocean Discharge
No effect:
• Western Australia (Perth):
• Organisms and lush plants living in discharge area
• Island of Antigua (Caribbean):
• Elevated salinity
• No effect on tropical reef ecosystem
Image found @ www.caribda.com
Conclusions
• Right now, not a lot of negative reports
• Could this trend change with increased
desalination worldwide?
• Will concern over the environment one day
shut down a region’s desalination
capabilities and their freshwater supply?
Works Cited
Anslow, Mark. "Salt of the Earth." The Ecologist 38 (2008): 12.
Beitel, Curtis B. "Meeting Tomorrow's Water Needs." Public Works 135 (2004): 22-25.
Bistany, Andrea S. "Navigating the Rising Currents Of U.S. Water Reuse." Water Environment & Technology 18 (2006):
20+.
Brannan, Paul. "Debunking Desalination." E: the Environmental Magazine Mar.-Apr. 2008: 16-18.
Burtka, Allison. "Desalination: What Happens Downstream." Water Environment & Technology 16 (2004): 16-18.
Champ, Michael A., David A. Flemer, and Gary M. Noland. "The 21st Century Environmental Crisis." Sea Technology
49 (2008): 81.
Conway, McKinley. "The Desalination Solution." The Futurist 42 (2008): 23-24.
Energy Recovery Inc. "Energy Recovery Inc. Prospectus." 1 Apr. 2008. Energy Recovery Inc. 1
Feb. 2009
<http://ipo.nasdaq.com/edgar_conv_html%5C2008%5C04%5C01%5C000095
0149-08-000046.html>.
Graber, Cynthia. "Desalination in Spain." Technology Review 109 (2006): S1-S8.
Miller, Wade G., and Jeffrey J. Mosher. "Got Water?" Water Environment & Technology 17 (2005): 76-80.
Reuther, Christopher G. "Saline solutions: the quest for fresh water." Environmental Health Perspectives 108 (2000):
A78-80.
"Tampa Bay Seawater Desalination Process." Tampa Bay Water. 17 Jan. 2008. 1 Feb. 2009
<http://www.tampabaywater.org/index.aspx>.
(No author listed) "The Price of Drinking Water." Environment 45 (2003): 5.
Voutchkov, Nikolay. "That's Enough Salt, Thanks." Water Environment & Technology 19 (2007): 96-99.
Voutchkov, Nikolay. "The Ocean: A New Resource for Drinking Water." Public Works 135 (2004): 30-33.
Water Science and Technology Board. Desalination - A National Perspective. Washington
D.C.: National
Academic P, 2008.
Images found at:
projects.gsd.harvard.edu
dotearth.blogs.nytimes.com
www.yannarthusbertrand2.org
www.ifh.uni-karlsruhe.de
wwn-online.com/articles/69197/
www.thameswater.co.uk
cleanocean.org
coal2nuclear.com
www.simsenv.com
www.caribda.com
Image found @ www.ifh.uni-karlsruhe.de