The Desalination and Water treatment presents a summary of the water supply challenges facing the United States, and suggests areas of research and development that may lead to technological solutions to these challenges. This Road map is a living document – updates to the Road map may be made on a regular basis to ensure that it remains current and relevant. The Roadmap may also be complemented by a series of additional documents, created as a result of meetings to be held with experts around the nation, focused on:
Desalination systems have the ability to remove salts from sea water and produce fresh potable water. The major desalting processes are:
Thermal Distillation Processes
- Multi-stage Flash Distillation.
- Multiple Effect Distillation.
- Vapour Compression Distillation.
- Solar Distillation.
- Reverse Osmosis:a
- ) with energy recovery,
- b) without energy recovery.
A typical RO desalting plant consists of three sections, namely pretreatment section, membrane section and post treatment section. Conventional pretreatment section typically consists of particulate filtration, micron filtration and chemicals additions. Membrane section consists of membrane elements housed in pressure vessels through which pretreated saline water is passed under pressure in excess of its osmotic pressure with the help of a high pressure pump coupled with energy recovery device.
The notion that water is a freely available resource will no longer be encountered anywhere in the world in 20 years time”
Worldwide sea water desalination has been a very effective and economical way of producing potable water for drinking and industries. It is a myth that, sea water desalination is exorbitantly expensive. But the fact that it is affordable.
Reverse Osmosis plants to convert sea water to potable drinking water and for other usages have been prevalent throughout the world for more than 3 decades. The sea water Reverse Osmosis membranes have improved in technology and efficiency over the last 15 years.
The current technology available for seawater Desalination through Reverse Osmosis System has proven to be cost effective and easily maintainable. With proper process design and efficient conservation of energy sea water Desalination system with Reverse Osmosis can be a long-term solution at an affordable price.
With technologies to save power such as “energy recovery turbines” cost per ltr of Desalinated sea water to potable water can work as low as US$0.001 per litre, including cost of running, maintenance and power.