Effect of Enhanced Coagulation with Diatomite on the Treatment of Oilfield Produced Water

Diatomite was used as core material to enhance the flocculation efficiency, the optimum parameters and the economic analysis of the compound coagulant, which composed of diatomite and PAC, used to treat oilfield produced water was determined in this study. The results showed that diatomite could improve the flocculation efficiency, when the reaction parameters were as below: PAC/diatomite = 1/4, compound coagulant dosage = 70~80 mg/L, pH = 6~9, temperature was 40degC, the removal rate of turbidity and suspended solid could reach over 88%. Compared with the only use of PAC as coagulant, the use of compound coagulant could save chemical cost by 28%.