Removal of pollutants from dilute wastewater by the PACTTM treatment process

Abstract

AbstractThe PACTTM wastewater treatment system, which incorporates the use of powdered activated carbon in a conventional activated sludge system, has been in use for the treatment of wastewaters from both municipal and industrial sources. The combination of physical adsorption with biological oxidation and assimilation in the PACT system has been shown to be particularly effective in treating dilute wastewaters which are variable in concentration and composition, highly colored, or contain materials which are refractive or potentially toxic to biological growth.Dilute wastewaters treated successfully in bench‐scale PACT systems include those from organic chemicals, pharmaceuticals, metal coating, shale oil retort water, evaporation ponds, leachates, and rainwater runoff. The COD of these wastewaters ranged from a low of 643 mg/l to 23,700 mg/l. Specific pollutants present included compounds such as phenols, cyanides, thiocyanate, pesticides, and priority pollutants. The PACT wastewater treatment process has successfully treated these wastewaters and produced effluents meeting POTW or direct environmental discharge requirements. Operational parameters and performance results obtained for a number of bench‐scale PACT systems are presented.