BALANCE OF HEAVY-METALS THROUGH A SEWAGE-TREATMENT WORKS .1. LEAD, CADMIUM AND COPPER

Concentrations of lead, cadmium and copper have been determined in the sewage sludges, sewages and effluent of a sewage treatment works. Treatment at this works is by primary sedimentation prior to biological treatment in a diffused air activated sludge plant. By analysis of composite samples corresponding to a 24-h input of raw sewage to the works, a mass balance of metals through the works has been estimated. The partition of the metals from raw sewage into the settled sewage and primary sludge, and from the settled sewage into the activated sludge and final effluent has been quantified. © 1979.