Desalination is a process that takes away mineral components from saline water. Desalination technology is widely used in the world to produce industrial water, drinking water, agricultural water and other related uses.

Modern desalination techniques include thermal (distillation) techniques and membrane filtration techniques. The Water desalination Methods are listed as below:

• Distillation
• Multi-stage flash distillation(MSF)
• Multiple-effect distillation(MED)
• Vapor-compression(VC)
• Ion exchange
• Membrane processes
• Electro-dialysis reversal (EDR)
• Reverse osmosis (RO)
• Nano-filtration (NF)
• Membrane distillation (MD)
• Forward osmosis (FO)
• Electro-Deionization (EDI)
• Freezing desalination
• Geothermal desalination
• Solar desalination
• Solar humidification–dehumidification (HDH)
• Multiple-effect humidification(MEH)
• Seawater greenhouse
• Methane hydratecrystallization
• High grade water recycling
• Wave-powered desalination

Advantages of Seawater Desalination are listed below that shows why desalination is a viable alternative to existing freshwater resources:

• Provides people with potable water (clean & fresh drinking water).
• Provides water to the agriculture & industries
• Water quality is safe (not dangerous or hazardous to any living thing).
• Uses tried-and-tested technology (the method is proven and effective).
• Helps preserve current freshwater supplies.
• Unlimited ocean water as source.
• Independent of changing factors.
• Plants are safely located.
• Help with habitat protection.

Reverse osmosis system (RO)

Reverse osmosis is one of the oldest and most popular separation techniques used mainly for the purification of water. This water purification process removes ions, unwanted molecules and larger particles from drinking water using a partially permeable membrane. As a result, the solute is kept on the membrane's pressurized side and the pure solvent is allowed to pass to the other side.

Advantages of Reverse Osmosis:

• This process can be used to effectively remove many types of dissolved and suspended chemical particles as well as biological entities (like bacteria) from the water.
• This technique has a wide application in treating liquid wastes or discharges.
• It is used in purifying water to prevent diseases.
• It helps in desalinating seawater.
• It is beneficial in the medical field.
• Bacteria, viruses and pyrogen materials are rejected by the intact membrane. In this respect, RO water approaches distilled water in quality.
• Available units are relatively compact and require little space. They are well suited to home dialysis.
• In average use, the membrane has a life of a little more than one to two years before replacement is necessary.
• Periodic complete sterilization of the RO system with formalin or other sterilant is practical.