Presentation Transcript

1. Desalination

   Presentation by Group 7
2. Areas of Investigation Background – What is desalination? Ethical implications Economic implications Environmental implications Social implications Political implications
3. Our mission As a group of individuals with different science backgrounds, we hope to help create a better understanding of desalination.
4. WHAT IS DESALINATION?
5. Desalination Desalination is the removal of an amount of salt (sodium) or other various minerals from water. This is mainly used to remove sea salt water to fresh water, making it suitable for human consumption The process of desalination is not very energy-effective, and consumes large amounts of energy and resources Desalination can be used in small scale situations, such as on submarines and ships to provide fresh-water for it’s occupants Many by-products are produced from desalination, most commonly table salt
6. Desalination Continued The largest desalination plant is in the UAE (United Arab Emirates), which produces 300 million cub meters of fresh-water annually The second largest, is located in Tampa Bay, and only produces roughly one eighth fresh-water as the plant in the UAE Especially useful for irrigation systems, as it can be extremely beneficial for third-world countries and distributed quickly
7. Reverse Osmosis Most commonly used method of desalination Removes salt and other minerals Pressure is used to drive water through a membrane, leaving behind brine Costs associated with reverse osmosis are mainly for electricity, membrane replacement and labour Brine must be carefully disposed to avoid deleterious environmental impacts
8. Electrodialysis Another common method of desalination Uses an electrical potential to drive ions through a membrane leaving water behind Membrane attracts salt ions leaving behind clean water Considerably expensive compared to other methods
9. Distillation Not very common method of desalination Saline water heated to produce water vapour Vapour condensed to produce freshwater Relatively expensive method of obtaining fresh water Aside from brine, has minimal environmental impacts
10. ETHICAL IMPLICATIONS Seems like an interesting idea with pros and cons, but how does its use effect living creatures around us ethically.
11. Costly Savings To save costs, some companies dump waste brine into oceans and streams, contaminating and destroying ecosystems Some plants use fossil fuels to power themselves Can be costly, the poorer regions that need the water the most may not be able to afford it
12. The Hope FIX THOSE ISSUES! new “Zero Liquid Discharge” technology ensures no brine released, but stored or sold=Boost for efficiency! With proper designing, power plant waste heat can be combined to power desalination plants Each year, new technology allows for cheaper and cheaper desalinated water
13. The Pros WATER FOR ALL!-1/5 of the water does not have access to clean drinking water, (CNA) This can be changed! SAVE OUR STREAMS-2.5% of earths water is freshwater, the vast majority is unusable ice/glaciers-all humans and non-ocean animals share the remaining fraction for all our uses and we’re running out!-Desalination makes use of the other 97.5% of water, : THATS A LOT OF WATER! (NRC)END THE CONFLICT-no more conflicts over freshwater, no more lawsuits, more living with a common humanity! -Water can be available to all! Providing clean water to earthquake victims without proper access, globalgiving.org
14. ECONOMIC IMPLICATIONS
15. Economic Effects Desalination reduces reliance on importing water. This is a major cost to a nation- fresh water will always have demand from all members of the population. This is notoriously expensive to continue; for example the cost of 1 bottle of water: $1.50 USD per Litre or $1,500 USD/m³ Desalinated water, costs US$0.75 - 6.00/m³
16. Economic Effects Another key aspect of Desalination is that it allows economic activity to remain unaffected by seasonal conditions. Desalination drought proofs a country by removing reliance on freshwater sources. Provides fresh water and prevents water borne disease to bounce back from hurricanes, monsoons or floods.
17. ENVIRONMENTAL IMPLICATIONS "Ocean water is filled with living creatures, and most of them are lost in the process of desalination," says Sylvia Earle, one of the world's foremost marine biologists and a National Geographic Explorer-in-Residence. We need to develop a method that is more environmentally friendly and energy efficient.
18. Impact on Marine Habitants Brine released back into ocean has potential to kill marine life Marine habitants get sucked into desalination plant equipment Release chemicals (used for pre-treatment and cleaning) which harms marine life Discharged waste has potential to rise water temperatures, affecting the habitants
19. Desalination Plants and Energy Use Plants produce large amounts of greenhouse gasses due to high energy needs Reverse osmosis uses about 10 times for energy than traditional methods
20. Use of Land Most desalination plants are located by the sea shore The land is used for industrial purposes rather than for recreation and tourism
21. CASE STUDYDESALINATION IMPACTS IN THE SOUTHERN EAST MEDITERRANEAN SEA
22. Other Environmental Implications Rising water temperature Discharged waster has potential to raise water temperatures of coastal waters It has adverse effect on marine like and water quality Impact on aquifers Danger of seawater or brine pipes leaking and penetrating aquifers with salty water Noise High-pressure pumps and energy recovery turbines produce loud noises Noise causes location of desalination plants to be far from population centers
23. Gaza Strip Made up of a 40 km coastline Very little fertile soil – only 13% is arable Overpopulated with high growth rates Poor sewage system which leads to waste in the Mediterranean Sea Many Palestinians fish along the eastern coast of the Mediterranean Coastal zone is very wide Has potential as an industrial zone Large continental shelf Sewage flowing into the sea.
24. Potential Impact in Gaza Strip Severe impact of brine in water coastal water Concentration of brine in coastal water could kill marine life Continental shelf will prevent use of deep outfall tunnel Unsafe for fishers History of pollution and oligotrophoic nature of sea make the Gaza Strip an unsuitable location for a desalination plant
25. Israel Costal Plains Israeli Cost of the East Mediterranean Sea is used extensively for fisheries and tourism Much of the costal plain of Israel is used for desalination activities rather than using it for recreation and tourism This has a strong impact mainly because there is a limited costal plain, especially in the north More of the costal plain is used for desalination plants than for recreation and tourism purposes Discharged brine solution could affect important marine plants particularly those with important commercial and medical values
26. SOCIAL IMPLICATIONS
27. Water is a basic human necessity and should be available for all citizens. However, the cost of desalination comes down to the consumer. Most communities cannot afford over hiked prices for desalted water. Therefore, desalination contributes towards social injustice. The low income communities are the ones that will also be affected by the plants as they will be built in industrial areas. This would cause air pollution, noise and traffic in and out of the plants. Ocean desalination can wreck havoc on marine life and many fish and other organisms get dragged into the plant and die. This causes loss of revenue for the fisherman and is unethical. Desalinated water is not always perfect and the process itself is not mastered. The water could become acidic to the pipes and to the digestive system. A lot of the water that exist the plant is waste and not drinking water therefore, it can be said that desalination is not very efficient.
28. According to EPA, these intake structureskill at least 3.4 billion fish and other organisms annually.Larger organisms are trapped against the intake screens,and smaller ones, such as fish eggs and larvae, are drawn through the intake screens and destroyed in the cooling system. As a result, fishermen lose at least 165 million poundsof fish today and 717.1 million pounds of potential futurecatch. This is equivalent to a $212.5 million economic lossto anglers and commercial fishermen.
29. Political Implications What does desalination mean for the governments and peoples of the world?
30. The Water Problem Lead to greater regulation of the world’s water Countries drain and pollute from common ocean basin Who has the right to ocean water and how much can be taken? How can countries be held responsible for pollution?
31. The Water Problem Coastal territory of greater importance Means of revenue as well as drinking water for people Water trade business becomes more prevalent as countries and corporations take possession of water War on water is a concern
32. Conclusion Desalination is provides the world with fresh water Current methods of desalination are expensive and leave an environmental footprint There is room for improvement To help create a better understanding of desalination, we have posted this presentation on http://www.scribd.com/doc/46572586/Desalination#aboutCHECK IT OUT!
33. Bibliography Canadian Nuclear Association. Desalination [homepage on the Internet]. Ottawa (ON): Canadian Nuclear Association; 2010. [cited 2010 Dec. 24]. Available from: http://www.cna.ca/curriculum/cna_nuc_tech/desalination-eng.asp?bc=Desalination&pid=Desalination Desalination Fact Sheet [home page on the Internet]. Sydney, Australia: n.d. [cited 2010 Dec. 27]. Available from: http://www.ffc.org.au/FFC_files/desal/Whatisdesal inati on-factsheet-1.pdf Electronics. (n.d.). Desalination. Water & Process Technologies: Water, wastewater and process systems solutions. Retrieved January 7, 2011, from http://www.gewater.com/what_we_do/water_scarcity/desalination.jsp General Electric. Desalination [homepage on the Internet]. Fairfield (CT): General Electric; n.d. [cited 2010 Dec. 24]. Available from: http://www.gewater.com/what_we_do/water_scarcity/desalination.jsp. National Research Council. Desalination: A National Perspective. Washington (DC): The National Academies Press; 2008. 312 p. Pereira G. Desalination - A Sustainable Water Supply for the Future [home page on the Internet]. 2011 Jan. 9. [Desalination - A Sustainable Water Supply for the Future; cited 2011 Jan. 9]. 1 p. Available from: http://www.caribbeanconstruction.com/index.php?option=.... Qutob M A. Environmental Impacts of Water Desalination Along the Coastal Region of Israel and the Palestinian Authority [home page on the Internet]. n.d. [cited 2010 Dec. 10]. Available from: http://www.ipcri.org/watconf/papers/mutaz.pdf