The chemical treatability of municipal wastewater

The performance of chemical precipitation on soluble and particulate contam inants in the municipal wastewater is investigated by chemical precipitatio n. For this purpose, jar test studies are performed by adding alum, ferric salts and lime at optimal dosages to the effluent samples collected from Ba ltalimanl and Yenikapl Preliminary Wastewater Treatment Plants, which are t wo of the major wastewater treatment plants in Istanbul. Particulate COD removal efficiency is 90% around optimal dosage except for lime, for both of the wastewaters. If lime is used, then the removal effici ency for the particulate COD becomes lower than the other chemicals. Solubl e TP removal efficiency is more than 93% for both of the wastewaters, but p articulate TP removal efficiency is 60-77% and less than 50% for Yenikapl a nd Baltalimanl wastewaters, respectively. Particulate TKN removal efficienc y was about 80% for both wastewaters. However, the removal efficiency of so luble TKN was lower than 20%.