机械清洗法对MBR膜泥饼层的影响

膜污染是制约MBR发展的瓶颈。考察投加ABS颗粒对MBR膜组件上膜泥饼层的影响,并设对照实验。结果表明,对照MBR膜通量下降速度快,膜污染严重,膜表面上累积厚厚的泥饼层,而在ABS MBR中膜通量下降速度则缓慢的多,且膜上泥饼层积累量则明显少于对照MBR;曝气量越大,颗粒运行的速度也越快,泥饼层被撞落量也越多;颗粒以碰撞角度为45°冲刷膜的情况下,泥饼层掉落效果明显增加;泥饼层包裹的膜丝根数越多,泥饼层的静摩擦力和保持泥饼层不被破坏的力也越大,泥饼层就越难被冲刷掉。SEM照片显示,ABS MBR的膜孔堵塞要严重于对照MBR,表面的褶皱要较对照MBR多。

Effect of mechanical cleaning method on MBR membrane sludge cake layer

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.