| In recent years, the combination of membrane separation technology and bioreactors has led to a new focus on wastewater treatment, which produced membrane bioreactors (MBRs). In comparison with conventional biological treatment systems, MBRs offer several advantages: high biomass concentration, good effluent quality and low sludge production, etc. Organic membrane modules are predominantly applied in MBRs due to their low cost. However, the organic membranes are easily contaminated. In contrast, inorganic membranes have relatively high resistance to chemical and thermal abrasion so that they are supposed to be applied in corrosive environments and at high temperatures.A novel metallic membrane module with 0.2um membrane pore diameter was used to treat simulative domestic sewage in an aerated membrane bioreactor. The removal efficiency of COD and nitrogen were studied, in addition, the improved effect of online backwash, offline cleaning and PVA Gel to the membrane fouling was studied.The experiment lasted 239 days and the results were desirable. The experimental results indicated that the average COD removal efficiency achieved 97.6%, and the nitrification was comparatively complete due to the heading off effect of metallic membrane to nitrate bacteria. SS can not be detected using standard filter paper. Membrane fouling could be alleviated effectively by the online backwash and intermittent work mode, thus the bioreactor could run steadily for a very long period. In addition, membrane permeate flux can be resumed to 87.0 % of its original level after offline cleaning using 0.3% (weight) NaClO+NaOH solution. Furthermore, the adding of PVA Gels in MBR as proved to reduce the membrane fouling.
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