|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