为使膜生物反应器工艺在取得高质量出水的同时能更有效地延缓膜污染,从而延长膜的工作周期和使用寿命,向生物反应器中一次性投加了1500mg/L的粉末活性炭(PAC)。同时该膜生物反应器采用恒温(30℃)、恒定膜通量(7L/(m^2·h))和间歇抽吸(开10min,停3min)的方式连续运行120d,结果表明,PAC的加入使活性污泥中的一部分微生物以PAC作为载体形成生物膜,从而在膜生物反应器中形成了以生物膜和活性污泥2种形式构成的新的生态系统,大大提高了膜生物反应器的污水处理效果.由于PAC的加入,改善了膜表面滤饼层的水力特性,从而减小了膜过滤阻力,有效延缓了膜污染.
In order to ensure that the MBR not only obtains high quality effluent but also lessen the membrane fouling to prolong the working period of the membrane module, the powdered activated carbon(PAC) was added into the bioreactor(the concentration of PAC was 1 500 mg/L). And the MBR has run continuously for 120 days with constant temperature(30 ℃ ), constant membrane flux(7 L/(m^2· h))and intermittent pump (the outlet pump run for 10 minutes and rests for 3 minutes). The experimental results showe that the biofilm on the PAC as carrier is formed, thus the biofilm and the activated sludge in membrane bioreactor produce new ecosystem which can improve the wastewater removal efficiency. In addition PAC changes the properties of the mixed liquor and the structure of cake layer on the surface of membrane module, and the filtration resistance is reduced. It is an effective way to lessen membrane fouling.