Membrane Bio Reactor (MBR) technique, a new method for wastewater treatment, integrates membrane separation and biotechnology, rejects activated sludge and macromolecular organic matter in aerobic tank/MBR tank with membrane separation plant, thus saving the use of secondary sedimentation tank. Consequently, the concentration of activated sludge rises greatly, the HRT and the SRT could be controlled separately, and difficult degraded matters are constantly degraded and reacting in reactor. Therefore, compared to traditional biological treatment methods, MBR technique greatly strengthens the function of the bioreactor with the using of membrane separation. Fig. shows the typical MBR concept of combination of Activated sludge process and membrane filtration.