Membrane bio-reactor (MBR) is a new type of wastewater treatment system that combines Membrane separation technology and biological treatment technology. The membrane module is used to replace the secondary sedimentation tank at the end of the traditional biological treatment technology to maintain a high concentration of activated sludge in the bioreactor and increase the organic load of biological treatment, so as to reduce the footprint of sewage treatment facilities and reduce the remaining sludge by maintaining a low sludge load. Membrane separation equipment is mainly used to intercept activated sludge and macromolecular organic matter in water. The concentration of activated sludge (MLSS) in the membrane bioreactor system can be increased to 8000~10,000mg/L or even higher. Sludge age (SRT) can be extended to more than 30 days.
Due to its effective interception, membrane bioreactor can retain microorganisms with a long generation cycle and achieve deep purification of sewage. Meanwhile, nitrifying bacteria can fully reproduce in the system, and its nitrification effect is obvious, which provides a possibility for deep phosphorus and nitrogen removal.