Treatment Effect of Printing and Dyeing Wastewater by Modified Filler Enhanced Combined MBR Process

The membranes bioreactor filled with modified fillers was used to treat the printing and dyeing wastewater,and its functions in removing the pollutants and reducing the membrane fouling were observed.The results showed that the reactor had a higher removal rate of COD and NH3-N,when the concentrations of influent and effluent COD were 436-1 722 mg/L and 43-79 mg/L,and the concentrations of influent and effluent NH3-N were 160-245 mg/L and 6.6-16.8 mg/L.The removal rates of COD and NH3-N were 88.99%-96.93% and 90.69%-96.94% respectively,and its effluent water quality can reach the second grade criteria of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB18918-2002).It was found that the membrane filtration resistance increased rapidly at the suction time of 20 min,and the membrane flux could better maintain the stability of membrane filtration performance at the suction time of 15 min.When the membrane flux was11.2 L/(m2·h),the transmembrane pressure showed an upward trend with the extending operation time,and the modified filling contributed the largest to reducing membrane fouling;the variation trend of ρ(MLVSS)/ρ(MLSS) ratio was similar to that of SOUR,the biofilm of system contained high content volatile organic compounds with high activity.Dosing of modified filler can effectively reduce the membrane fouling and greatly extend the membrane cleaning cycle.