Essay on Seawater: Water and Drinking Water

Submitted By Josh Divona-Jen Norr
Words: 621
Pages: 3

Joshua DiVona
January 9, 2015
Frank Laccone

The Sea water has many different features then regular water. Seawater is a solution of dissolved organic molecules, dissolved gasses, and inorganic salts. The solution only makes up about 3.5 percent of the water while the other 96.5 percent is pure water. Much of the properties depend on the depth of the water how close to land it is and its latitude.
When it comes to our drinking water, we use fresh river water or water from the aquifer. The reason for this is the price. If we were to convert ocean water into drinking water it, would cost between one and two dollars for every 264 gallons. Using the fresh water we use now the price is closer to 10-20 cents. The reason for this price difference is it takes a lot of energy to dissolve the salt. This will not be the case years from now because the water sources will deplenish. Even if they were to build dams that would cause the cost to rise as well. There are roughly about 13,000 desalination plants worldwide. These plants will make about 14.7 billion gallons of drinking water a year. Most of the plants are in a location where oil is more readily available and cheaper. Saudi Arabia is one of the countries that take advantage of using the salt water. The United States also uses salt water as well it just isn't as common. The largest plant in the United States is located in Tampa, Florida.
There are two basic methods to convert seawater into drinking water. You have membrane separation and thermal distillation. Thermal distillation is a simple process. This process makes vapor by boiling the water. When the water boils just as you do on the stove it produces the steam. This vapor is then collected and cooled down providing the salt-free water. When it comes to the method of membrane separation, the most typical process is known as reverse osmosis. This method is more cost effective and is the reason the plant in Tampa uses it. During the reverse osmosis process, there are five steps. Step 1 removes the minerals that cause hard water using an ION Exchange water softener. Step 2 is the use of an Activated charcoal filter, and this removes the bad taste and odors. The third step removes the partials larger than five microns using the five