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Want total chromium removal from wastewater to below 0.6 mg/l

July 10, 2009

Hello,
We have an hexavalent chromium treatment plant successfully treating 10 Cu.M/day capacity that converts Cr+6 to Cr+3 on acidification and addition of sodium bisulphite using Oxidation-Reduction Potential meter. Thereafter it is precipitated with lime and settled and overflow liquid is filtered to reduce total chromium level to below 0.6 mgpl. Is it possible to reduce below 0.6 mgpl with some additional technology, etc. Kindly advice. Thanks

Glenn DSouza
Product Designer - Mumbai, India

Try extending the stirring period and/or lowering the pH in the metabisulfite step; also, add a bit of ferrous sulphate ferrous sulphate [affil links].

Dave Wichern
Consultant - The Bronx, New York
July 14, 2009

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