MUMBAI, FEBRUARY 10: There is relief in the offing for coastal areas receiving scanty rainfall. The Bhabha Atomic Research Centre (BARC) has come up with an indigenously developed desalination plant now in the process of being set up at Kalpakkam in Tamil Nadu.More importantly, the project has come in time to rescue the Russian-aided Kudankulam Atomic Power Station situated in a belt south of Thirunelveli in the state, where the annual rainfall ranges between nil to 100 mm, never exceeding 400 mm in any given year. The 1000x2 power plants slated to begin construction in 2003 were strapped for water and it was planned to draw the water from Pechiparai dam 65 kms away through a pipeline and that only to the extent of 4 cusecs (cubic feet per second). However with BARC's "demonstration" scale plant "positively" set to go operational in March 2002 at Kalpakkam where it will supply water to the Kamini research reactor, Kudankulam's problem will be solved and in addition, the entire belt is set to benefit by theexercise.Speaking to The Indian Express on Thursday, a reliable source said that the pilot prototype plant had been in operation in Trombay for the last five years. Based on that experience, the indigenoulsy developed plant was now being fabricated with an investment of Rs 31 crore sanctioned in the Ninth Plan for the prestigious showcase achievement of the BARC.Desalination of sea water uses two types of technology. One is by the evaporation or distillation process and the other through the membrane process. Through the first method, water to the purity of 10 parts per million (PPM) saline content and by the membrane process a purity of 400 PPM saline content has been achieved. The salinity of sea water is 35,000 PPM and the permissible limit for potable purposes is at 500 PPM but, this, said the source, was extendable up to 1000 PPM. The BARC had now perfected both technologies. The evaporation process uses the multistage flash technoloy (MSF) and the membrane process uses reverseosmosis.The design for the Kalpakkam plant was such that both technologies would be utilised and the two waters blended to the level of 150 to 200 PPM to achieve the salinity level of river Palai from where water is now being drawn. The cost works out to around Rs 45 per 1000 litres, the source said.The Kalpakkam demonstration plant would be precursor to the Kudankulam plant which will be a commercial venture and produce 20,000 cu metres of water for the plant and the township.The cost effective desalination technology developed by BARC is bound to be a boon for coastal Tamil Nadu and also for Mumbai as a back up for failure of monsoon or inadequate rainfall or even to augment water supply to the city in the future.
