罗非鱼养殖尾水絮凝去除效果研究OA北大核心CSTPCD

Tilapia farming effluent contains a large amount of suspended particles such as uneaten feed and feces,which are the main carriers of nitrogen and phosphorus nutrients.Discharging the effluent into surrounding water bodies can lead to eutrophication.The common effluent treatment methods currently have disadvantages such as large land occupation,high investment,and low efficiency,affecting widespread adoption.To address this issue,this paper explores useing the flocculation process to treat tilapia farming effluent,selecting four flocculants:polyferric sulfate,ferric chloride,chitosan,and magnesium carbonate.By comparing the removal effects on turbidity,total suspended solids(TSS),and chemical oxygen demand(COD),a suitable flocculant for effluent treatment is selected.The results show that polyferric sulfate outperforms the other three flocculants(ferric chloride,chitosan,and magnesium carbonate).With a dosage of 0.4 g/L,pH=8,and flocculation time of 15 minutes,polyferric sulfate achieved removal rates of 96.7%for turbidity,92.6%for TSS,and 95.1%for COD.Evaluation of the flocculated flocs revealed that the height of floc settling has a certain correlation with the turbidity removal rate,and the growth of the flocs is affected by nucleation.The zeta potential before and after effluent treatment suggests that polyferric sulfate purifies the effluent by disrupting the stable structure of suspended particles in the water.Therefore,polyferric sulfate can be selected as a flocculant in treating tilapia farming effluent.