Landfill leachates are generated from municipal solid waste landfills under the action of water percolating through the landfilled waste. A treatment system Using a combined membrane engineering process was developed to effectively treat the landfill leachate in the Dahanzhuang sanitary landfill (Tianjin, China). The process combines a membrane bioreactor (MBR) and nanofiltration (NF) technology to treat the leachate. The results indicate that the NF system, including the hollow-fiber NF membrane, is an appropriate advanced treatment alternative for landfill leachates. This system provided good removal of chemical oxygen demand and color. The membrane flux renewal reached over 96% after washing with 0.01 mol/L HCl. As a result, the effluent water quality met effluent discharge standards (GB16889-2008). (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 116: 2343-2347, 2010