Pilot-scale Study on Treatment of Micro-polluted Water With PAC and Ultrafiltration Integrated Process

The combined process of coagulation sedimentation and powdered activated carbon (PAC) addition in immersed ultrafiltration was used to treat Beijiang water for about 70 days continuous running. Effects of different PAC dosages on removal of turbidity, UV₂₅₄, COD_Mn, and membrane fouling were investigated, including the effect of retention-time on membrane fouling recovery.Resultsindicated that PAC could increase organic matters removal effectively, UV₂₅₄ removal increased to 27.00%, 43.17% and 52.97%, and COD_Mn removal increased to 6.70%, 20.91% and 22.98% at the dosage of 5, 10 and 20 mg/L, however, the function decrease gradually during 24h after dosing. PAC addition have an effect on mitigating membrane fouling at the same time. It could meet the demand of economics and effluent quality at the dosage of 5-10 mg/L. When cleaning the fouled membrane with NaClO, the membrane flux could recover at the retention time of 4-6h.