The reason as to why we do not get our drinking water from the ocean is that the desalination of water requires a lot of energy. Energy and technology to desalinate water are both expensive which means that desalinating water can be pretty costly and also prefered the use of local fresh water than to desalinate seawater.
How energy is used to separate salt from water.
There are two methods of breaking the bonds in saltwater which are;
- Thermal distillation.
- Membrane separation.
Thermal distillation involves boiling water and turn it into vapour leaving the salt behind that is collected and condensed back into water by cooling it down.
most type of membrane separation which is commonly used is called reverse osmosis that force Seawater in a semipermeable membrane that separates salt from water. Technology typically requires less energy than thermal distillation which lead to most new plants to use reverse osmosis.
On my next research i will be looking on various ways in which water undergoes in order for it to be treated.