HYBRID MEMBRANE FILTRATION PROCESS FOR LEACHATE TREATMENT

A hybrid technology known as the ultrafiltration-biologically active c arbon (UF-BAC) process that amalgamates adsorption, biodegradation and membrane filtration is found to be highly efficient for treatment of landfill leachates. The process employs bioactive powdered activated c arbon (PAC) with a leachate-acclimated microbial culture for the simul taneous sorption and biodegradation of organic constituents. Tubular c ross-flow ultrafiltration membrane modules separate out colloids and m icroorganisms, and a high quality permeate is obtained. Batch biokinet ic studies were performed for the two leachates to evaluate their exte nt of biodegradability and biodegradation kinetics. The process effici encies for both leachates were in the range of 95-98% in terms of TOC removal, and exceeded 97% for specific organic pollutants. The UF-BAC process compared well with the PACT process in terms of organic remova l, and produced higher quality effluent in terms of suspended solids ( 100% removal). The study demonstrated that addition of 1% PAC mitigate d permeate flux deterioration attributed to membrane fouling and conce ntration polarization, and enhanced permeate transport. Possible mecha nisms for flux amelioration are discussed. Copyright (C) 1996 Elsevier Science Ltd