Membrane bioreactor is a new type of wastewater treatment system that organically combines membrane separation technology and biological treatment technology. The membrane module replaces the traditional biological treatment technology at the end of the secondary sedimentation tank, in the bioreactor to maintain a high concentration of activated sludge, to increase the biological treatment of organic load, thereby reducing the footprint of wastewater treatment facilities, and by maintaining a low sludge load to reduce the amount of residual sludge. The membrane separation equipment immersed in the aerobic biological tank is mainly utilized to retain the activated sludge and macromolecular organic matter in the tank. The concentration of activated sludge (MLSS) in the membrane bioreactor system can be increased to 8,000 to 10,000 mg/l or even higher; the sludge age can be extended to more than 30 days.
Membrane bioreactor can retain microorganisms with long generation cycle due to its effective retention effect, which can realize the deep purification of sewage, while nitrifying bacteria can fully reproduce in the system, and its nitrification effect is obvious, which provides the possibility of deep phosphorus removal and denitrogenation.
Compared with the traditional biochemical water treatment technology, the membrane bioreactor has the advantages of high treatment efficiency, good quality of effluent, compact equipment, small footprint, easy to realize automatic control, simple operation and management.
The technology is still in the pilot stage in the livestock and poultry breeding sewage treatment.