No abstract

No abstract

No abstract

No abstract

In this study, coagulation-sedimentation process was adopted to treat harbor oily wastewater. Single-factor experiments showed that the optimum parameters were dosage of poly-aluminum chloride (PAC) of 150mg L -1 and polyacrylamide (PAM) of 2.5 mg L -1 ; pH of 7.5. The mixture was stirred vigorously for 1min at the rotational speed of 300r min -1 , then stirred for 10min at 100r min -1 , and 10min at 50r min -1 , then settled for 30min. Under these conditions, COD concentration was reduced from 481 ～510mg L -1 to around 200mg L -1 , oil content from 21～36 mg L -1 to 10～15 mg L -1 , and SS from 153～197 mg L -1 to 21～34 mg L -1 . Meanwhile, it was observed a linear relationship between removals of suspended solid (SS) and oil content, indicating the oil pollutant was mainly absorbed on the suspended solid.