The membrane biological reactor (MBR) is a novel water treatment technology combining a membrane separation unit with a biotreatment unit, replacing the secondary settling tank by a membrane component to keep concentration of sludge with high activity in the bioreactor and to reduce occupation of wastewater treatment facilities, as well as keeping low sludge load to decrease output of sludge. The filtration of the MBR membrane makes microorganism completely intercept in the bioreactor, realizes thorough separation between the hydraulic retention time and active sludge age, and removes sludge expansion problem in the conventional active sludge method. Compared with conventional biochemical water treatment technology, MBR is featured with high treatment efficiency, good yielding water quality, compact device, little occupation, easily-realized automatic control and simple running management.

1. Efficient solid-liquid separation is performed with better separation effect than conventional settling tank. The yielding water has good quality, zero-close suspended substances and turbidity, so the yielding water can be recycled directly.

2. High-efficiency interception function of the membrane makes the microorganism completely intercept in the bioreactor, realizes thorough separation between the hydraulic retention time (HRT) and the sludge retention time (SRT), as well as realizes flexible and stably running and control.

3. As MBR combines the aeration tank with the secondary settling tank in the conventional wastewater treatment together, and substitutes total technical facilities in three-stage treatment, this technology reduces occupation a lot and saves civil engineering investment.

4. It is beneficial for interception and propagation of nitrobacteria and achieves high nitrification efficiency in the system. In addition, it can be added with functions such as deamination and dephosphorization by changing the running method.

5. The sludge age can be a long time greatly, which improves the degradation efficiency of difficult degradable organic matters.

6. The reactor runs under high volume load, low sludge load and long sludge age, so the residual sludge yield is very low. As the sludge is used for a long time, the zero-sludge discharge can be realized theoretically.

7. The system is controlled by PLC with convenient operation and management.