Effect of mechanical cleaning method on MBR membrane sludge cake layer
机械清洗法对MBR膜泥饼层的影响

Membrane fouling is an important factor of restricting the application of membrane bioreactor (MBR). The mechanical cleaning technology was used in MBR to control the sludge cake formation on membrane. The result indicated that the membrane flux was declined quickly in controlled MBR and membrane fouling was serious, where a thick sludge cake layer was deposited on membrane surface. In the ABS MBR, the membrane flux was declined slowly and the sludge cake on membrane was obvious less than that of the controlled membrane. The larger air flow rate was, the faster speed of particle was. Particles collision the membrane at a 45 degree angle could wash out down more sludge compared to particle straight collision. The static friction force and the force that protect the structure of larger sludge were became larger when more membrane silks were contained in sludge cake. SEM picture showed that the membrane hole of ABS MBR was clogged more serious than that of the controlled MBR and the membrane surface of controlled MBR was smooth than that of the ABS MBR.