Electro-coagulation Treatment of Wastewater from Paper Industry

摘要

The objective of this paper is to find the optimal operating conditions for the removal of Total Suspended Solid (TSS) and Chemical Oxygen Demand (COD) of wastewater from paper industries by electro-coagulation techniques. The electro-coagulation process is more effective, quick and feasible method for treatment than chemical coagulation. The effect of key operational parameters, including the type of coagulant, initial pH, current density, and duration of treatment, on the percent removal of TSS and COD were investigated. Iron (III) Sulphate Fe_2(SO_4)_3 (Fe), and Calcium Carbonate CaCO_3 (Ca) salts were used in this study, alone, and as an aid to the electro-coagulation technique. Under the optimal operational conditions (initial pH =8, t = 30 min and J =60 A/m~2), the treatment of wastewater from paper industries by electro-coagulation alone has led to a removal of TSS and COD of 82% and 84%, respectively. The electro-coagulation process was then combined with the addition of the Fe and Ca salts at the same optimal operational conditions. The addition of Fe resulted in about 95% and 96% removal of TSS and COD, respectively. The addition of Ca resulted in about 90% removal for both TSS and COD. The results indicated that the two salts when combined with electro-coagulation technique have minor effect on the % removal of TSS and COD. The two salts have similar effect on the % removal. The Fe salt, however, has slightly more effect than Ca on the percent removal of TSS and COD.