A New Desalination Plant at Kavaratti to Supply Drinking Water from Monday

A new desalination plant is scheduled to become operational on Monday in Kavaratti in the presence of the Minister for Science and Technology and Ocean Development, Shri. Kapil Sibal and the Minister for Power, Shri. P.M. Sayeed.

The Plant will use "Low Temperature Thermal Desalination" technology. In this method relatively warm water is flashed inside a vacuum flash chamber and the resultant vapour is condensed using cold water.

The temperature difference which exists between the warm surface sea water (28 to 30 degrees Celsius) and deep sea cold water (7 to15 degrees Celsius) would be effectively utilized to produce potable water apart from power generation, air conditioning and aquaculture.

This technology has been utilized in the first ever low temperature thermal desalination plant which has been commissioned at Kavaratti. The plant is housed in a structure on the shore. The bathymetry at the island is such that 13 degrees Celsius water is available at a depth of 350m at a distance around 400m from the shore. The cold water is brought to the surface through a 600m long pipe. The technology was first demonstrated in a pilot project of 5000 liter/day at Chennai and is now being used for the first 100,000 liter/day plant at Kavaratti. The cost of desalination would be around 25 paise per litre and will progressively cost less as the capacity is increased.

Though the concept was known for a long time, due to practical difficulties it was never attempted. This approach of providing water is extremely useful for islands like Kavaratti where there is no other source of fresh water and the environment is extremely fragile.

This opens a new vista for setting up much larger barge mounted desalination plants to address our ever increasing need for potable water

Source : Ministry of Science & Technology
Date : May 20, 2005