Study on Environmental Materials with Treatment of Sweet Potato Starch Wastewater by Coagulation Precipitation Method

Abstract

This study aimed at, pre-treatment of sweet potato starch wastewater and acquisition the application conditions of environmental materials though coagulation precipitation. The removal rates of COD and turbidity were investigated by process to find kind and quantity of suitable coagulant, quantity of coagulate aids, pH and setting time. The results showed that poly aluminum ferric chloride (PAFC) was chosen as an optimum coagulant for effective treatment. The optimal coagulation precipitation conditions were determined as follows: pH8, dosage of PAFC 1200mg/l, PAM100mg/l, sedimentation time 30 min. At optimum conditions of coagulation precipitation stages, the removal rate of COD and turbidity reached 25.8% and 67.5%, respectively. Therefore, coagulation process reduced the burden of subsequent wastewater treating.