Indian researchers develop leather pollution technology
The India-based Central Leather Research Institute (CLRI), a constituent body of the Council of Scientific and Industrial Research (CSIR), claims it has developed a technology that checks pollution due to effluents from leather units.
The technology, called SRIOM (Salt Recovery from Inorganic and Organic Mixture), helps separate sodium chloride and calcium chloride contained in the evaporated residue of reverse osmosis (RO) rejects.
“It is a one-time disintegration process. There is no single report available on the recovery of sodium and other chlorides from the evaporated residue of RO rejects stream containing high concentration of organic salts,” said G Sekaran, head and deputy director (environmental technology division), CLRI.
“This process not only helps the leather industry to achieve zero liquid discharge (ZLD) but also makes use of this high purity salt in the chemical and pharmaceutical industries apart from using it as edible salt,” Mr Sekaran pointed out. The technology got an Indian patent in 2010. “The existing data suggest the treated tannery wastewater contains high amount of total dissolved solids (TDS), besides dissolved organics estimated as BOD5 and COD. Hence, the secondary biological treated waste water is subjected to membrane separation process for the recovery of water in the presence of refractory organics and inorganic salts,” Mr Sekaran said.
Mr Sekaran said since the technology had been successfully tested on a pilot basis, it would be soon taken up at the cluster level and then on a mass basis.
He added that the centre had been approached to give the technology a major push in the 12th Five-Year Plan with necessary monetary support. According to Mr Sekaran, there are 925 leather units in Tamil Nadu with 9 common effluent treatment plants (CETPs), where this technology can be used. Mr Sekaran said CLRI or CSIR could license this technology to leather clusters in India, while holding the patent for it.
