The effects on treatment of wastewater from Channel Catfish slaughtering by using different flocculants were compared, the results showed that PFS was the most efficient flocculant. The effects of placed time, pH value, dosage of PFS, mixed time and temperature on treatment of wastewater from Channel catfish slaughtering were studied, the cross design with four levels and five factors showed that the optimum flocculation conditions were placed time 4 hours, pH value 9, dosage of PFS 6g/L, mixed time 6 min, temperature 20℃. And the removal rate of protein, CODcr and SS reached 91.65%, 88.42%, and 98.89% respectively.After that, the wastewater was treated by ultrafiltration and nanofiltration. The effects of operation pressure, pH value, temperature and time were studied, the results indicated that the optimum ultrafiltration and nanofiltration conditions were operation pressure 0.1Mpa, pH value 7, temperature 20℃, time 2h feeding flux of 10L/h and 0.6Mpa, pH value 7,temperature 20℃, time 2h feeding flux of 6L/h. The water flux recovery of the membrane was up to 96.71% and 96.00% by using cleaning reagent. The effluent with the pH value 7.06, protein value 5.82μg/ml CODcr value 109.00mg/ml, SS value 5.00mg/L can meet the Discharge Standard of GB 13457—92 and the main contamination CODcr is 100 mg/L. The amino acid and toxicity analysis indicated that the flocculation were abundant in protein and amino acid, and the concentration of As,Pb can meet the Discharge Standard of GB 13078-91. So they can be used in feeding and farming.
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