Feasibility Study of Conventional Coagulants and Fenton Reagent for High Chemical Oxygen Demand Wastewater

Attempts were made in this study to examine the effectiveness of conventional chemical coagulation and flocculation process using ferrous sulphate, alum and Fenton process for the treatment of high chemical oxygen demand (COD) industrial wastewater. Removal of organic matter (expressed as COD) was investigated for highly organic wastewater having COD of 15000 mg/L. Also, the optimum conditions for coagulation/ flocculation process, such as coagulant dosage, Fenton dosage and pH of solution were investigated using jar-test experiment. The results revealed that in the range of pH tested, the optimal operating pH was 7.5-8 for FeSO4 and alum and 3 for Fenton process. Percentage removals of 26, 42 and 88 for COD was achieved by the addition of 1.0 g/L alum, 1.2 g/L of FeSO4 and 1:20 Fe2+/H2 O2 ratio, respectively. It can be concluded from this study that coagulation/flocculation may be a useful pre-treatment process for high organic load industrial wastewater prior to biological treatment.