Treatment of biological waste water using activated sludge process

A study was conducted to evaluate the feasibility of activated sludge process for the treatment of synthetic wastewater and to develop a simple design criteria under local conditions. A bench scale model comprising of an aeration tank and final clarifier was used for this purpose. The model was operated continuously for 210 days. Settled synthetic wastewater was used as influent to the aeration tank. Chemical oxygen demand of the influent and effluent were measured to find process efficiency at various mixed liquor volatile suspended solids and hydraulic detention time. The results of the study demonstrated that an efficiency of above 90% for COD could be obtained if the ASP is operated at an MLVSS concentration of 3,000 mg/L keeping an aeration time of 1 h. The results of this work might offer significant insights in the perceptive use of activated sludge process for the treatment of municipal and industrial waste water.