Experimental research on coagulation floating combination process used in oily wastewater

The flotation process were tested by the method of coagulating sedimentation in oily wastewater. The influence of PAC, PAFC, complex coagulation agent (PAFC + PAM) and the solution pH value on the oil removing effect after coagulation were studied. The coagulation tests showed that: the complex coagulation agent has the best effect, with the best dosage of PAFC 400 mg /L, PAM 1 mg /L and the best pH value range of 6 to 10, when the removal rate of oil was 95%. The flotation process experiments show that : in the optimization condition, with the PAFC dosage of 250 mg /L, PAM dosage of 1 mg/L, the removal rate of oil can reach 98%. Results show that: the flotation process has better effect than the coagulating sedimentation process on the treatment of oily wastewater.