Desalination

__**Desalination**__ is : a process of removing salt from ocean water. The reason people are doing this process of desalination is because there is a big demand for fresh water for things such as: drinking water, industry, and irrigation. We can meet these needs by converting ocean water to fresh water. This is one way to increase fresh water supply. These methods are very costly($). There are 3 methods for desalination. The first method of desalination is : //**__D____istillation__**.// This is when you get ocean water and heat it up to remove salts. This heat causes the liquid water to evaporate leaving the salts behind. The salts stay behind because when water evaporates only the molecules are evaporated. Then when the water vapor condenses what you are left with is fresh water. This is a very good method but it requires a large amount of costly heat energy. The second method of desalination is __**//Freezing//**__. This is when you get ocean water and freeze it. What occurs in this process is that when the water freezes only the first ice crystals that form do not contain salt. This ice can be removed and melted to get the fresh water. This process requires about 1/6 of the energy needed for distillation. The third and last method for desalination is __//**Reverse Osmosis**//__. This is when you put ocean water through very high pressure. What happens in this process is that you use these special membranes that have holes large enough to let water trespass but still small enough not to let salts go through it. This entire process occurs under very high pressure.
 * **//Distillation//**
 * **//Freezing//**
 * **//Reverse Osmosis//**