Tata Chemicals plans to invest Rs 50 crore to set up a new water purifier-making plant in 2010/11, a top official said on Wednesday.

"We are yet to finalise on the location of the plant, but since rice husk is the key raw material, it should be close to a rice producing belt," R Mukundan, told reporters.

The total capacity of the plant would be 500,000 units annually and the work at the plant would commence by the end of this fiscal, he added.

The firm already has a water purifier plant at Haldia in the eastern state of West Bengal with an annual capacity of 1 million units, he said.

The firm, which sells water purifiers under the brand name 'Swatch', expects to sell 1 million units during FY11, which would generate revenue of Rs 75 crore, Mukundan said.

"Currently, we are selling about 50,000 units a month and with the launch of low priced varients, by the end of the fiscal it would reach an average of 80,000 units a month."