Pilot testing was conducted to evaluate the relative performance of 4 filter media, including Ceraflow-50, as part of a reduction coagulation filtration (RCF) treatment process for the removal of hexavalent chromium (Cr(VI)) from groundwater. This evaluation was conducted at multiple well sites for a water utility in California.
The RCF process achieves Cr(VI) removal by reduction to the less soluble trivalent chromium (Cr(III)) using a reductant – i.e., ferrous iron, coagulation, followed by filtration of the chromium laden particulate. Following the reduction step, any remaining ferrous iron is oxidized to ferric hydroxide via aeration or chlorine addition, and then filtered, removing the chromium particles. RCF for Cr(VI) removal is akin to arsenic removal with coagulation filtration with the exception of the reduction step and the use of ferrous, rather than ferric iron as a coagulant