Copyright © 2011 SciRes. ACES Pretreatment of Wastewater Streams from Petroleum/Petrochemical Industries Using Coagulation

Coagulation-flocculation processes using different types of conventional coagulants, namely, ferric chloride (FeCl3), aluminum sulfate (AL2(SO4)3·18H2O), lime and ferrous sulfate (FeSO4) were investigated using the Jar-test technique. A further aim is to determine the optimum conditions for the treatment of industrial wastewater effluents i.e. coagulant dosage, mixing rate, temperature and pH control. Under optimal condi-tion of process parameters, coagulation/flocculation process was able to lower the turbidity well below the permissible level (1.8 NTU). The results indicate that ferric chloride had superior efficiency compared with other coagulants with efficient dose of 800 mg/l. The optimal initial pH of the effluents that enhanced the turbidity removal was 8.6. The temperature showed no significant effect on the turbidity removal