|
|
|
Seawater desalination is a process that removes salt from water. While a swallow or two of salty water while swimming in the ocean or Gulf isn't bad, humans cannot survive on salt water. Salt water makes a person more thirsty and eventually would make you suffer from dehydration. Desalination can create additional sources for public water supply and help areas where the groundwater aquifers are having trouble supplying all the water that is needed. Even with seawater desalination we still need to conserve water. Desalination can only meet a small percentage of our water needs. The most common process of desalination involves using high pressure to force salty water through a semi-permeable membrane. A membrane is made from material that allows liquid, but not solids (like salt) to pass throught it. After the water has passed through the membrane, what is left is purified water and a concentrated byproduct (salt). This process is called reverse osmosis. Although there are other ways to desalinate, reverse osmosis is the most common. Florida is building the first large-scale (25 million gallons per day) seawater desalination plant in the U.S. This plant is scheduled to be in operation by the end of 2002. Two drawbacks to desalination have been the high cost of the energy needed to operate the plants and the safe disposal of the plant's highly concentrated salt byproduct. Researchers are finding new ways to desalinate water with less energy and ways to dilute the concentrated salt so it can be safely returned to the body of water it came from and not harm marine life. Desalination is one process that will help create an additional source of public water supply and help keep the groundwater aquifers from being drained dry. Using reclaimed water (water which has received at least 2 treatments in a wastewater treatment plant) to water lawns and landscapes, to cool power plants and to recharge groundwater supplies will also help conserve our natural water supply. Although it is often clean enough to drink, reclaimed water is kept out of the public water supply.
| ||||
|
|
