In a step to protect rivers especially Ganga from pollution, Environment Minister Jairam Ramesh on Sunday launched a new green technology that prevents water released by the leather processing units from contaminating the river.

"Close to 50 percent of the leather processing units in the Ganga river basin are located in Uttar Pradesh (Jajmau, Unnao and Banthar) and West Bengal. Together they use about 3,000 tonnes of salt each day to preserve 5,000 tonnes of raw hide," Ramesh said after launching the technology in Kanpur (Uttar Pradesh).

"Close to 90 percent of this salt finds its way into the Ganga and groundwater leading to pollution and contamination," he said.

The new lyophilisation technology developed and patented by the Environment Ministry's Central Pollution Control Board (CPCB) enables salt-free preservation of hides.

"It also brings down the amount of water used in the process, is low on chromium intake and makes for more cost-effective effluent treatment," the Minister said lauding the CPCB for its initiative.

The conventional process of leather preservation across various stages of processing uses large amounts of salt.

Owing to this, tannery effluent is characterised by high amounts of dissolved solids, making effluent treatment difficult and expensive.

Ramesh exhorted the leather industry to adopt this technology on a large-scale without the Union Environment Ministry having to pass laws to make its use compulsory.

He said over the next two years, the leather industry will need to install around 900 such lyophilisers with each unit costing between Rs 60 lakhs and Rs 2 crore.