Removal Of COD And Turbidity From Urban Wastewater By Electrocoagulation Using Aluminium Electrodes: Process Optimization By Response Surface Methodology

Document Type : Primary Research paper

Authors

Department of Chemical Engineering, JNTUA College of Engineering Ananthapuramu, Ananthapuramu, India, 515002

Abstract

Due to extensive industrialization, increase in population and rapid urbanization, management of wastewater has become essential to prevent damage to the receiving water bodies. Urban wastewater includes wastewater from domestic, commercial and industrial areas. There are various conventional treatment methods in use. In this study electrocoagulation technique is adopted to reduce COD and turbidity. Urban wastewater is rich in organic matter and nutrients. It is subjected to the electrocoagulation treatment using aluminium electrodes and the reduction in the COD and turbidity was examined. Conductivity, pH, runtime, voltage and agitation speed are the factors that affect the performance of electrocoagulation. The experimental factors are optimized using response surface methodology (RSM) and a second order polynomial regression model is developed. At pH 6.95, conductivity 3.07 mS/cm, runtime of 48 min, voltage 6 V and agitation speed 215 rpm, the COD and turbidity removal efficiency are 88.42% and 85.16% respectively. The anodic dissolution at optimal conditions is 0.00432 g/cm2. The energy consumption for the optimal reduction of pollutants is 1.68 KWh/m3 and the quantity of sludge produced is 0.102 kg/m3. The treated water is fit to be discharged into natural water bodies.

Keywords