通过 MBR 膜分离单元处理污水处理厂生物池混合液的中试,分析了平板膜和中空纤维膜的跨膜压差(TMP)与间歇出水时间、曝气强度、膜通量、污泥浓度等运行参数的关系,比较了两类膜的运行特性。结果表明,两类膜的 TMP 上升速率随抽停比的增加而增大,最佳抽停比均为9 min∶1 min,抽停比变化对平板膜 TMP 的影响更为明显；平板膜和中空纤维膜的适宜曝气强度分别为1.20 m3/(m2·h)和0.60 m3/(m2·h)；两膜的临界通量介于20~25 L/(m2·h),平板膜的临界通量稍低于中空纤维膜；在8000~15000 mg/L 的污泥浓度内,平板膜的最佳运行污泥浓度高于中空纤维膜。对于处理规模为1万 m3/d 的市政污水 A2/O-MBR 项目,采用平板膜时项目总投资为4200万元、运行成本为1.36元/m3,采用中空纤维膜时项目总投资为3900万元、运行成本为1.19元/m3。%The effluent of biological reaction tank of a wastewater treatment plant was treated simultaneously by a flat sheet membrane (FSM)and a hollow fiber membrane (HFM)in a pilot test.To compare the operation characteristics of the two membranes,the relationship between transmembrane pressure (TMP)and parameters such as relaxation duration/frequency,aeration intensity,flux and MLSS were analyzed.According to the results of the pilot test,the TMP rising rate of the two membranes increased with the increasing of on/off ratio and their best on/off ratio were both 9 min∶1 min;meanwhile,the TMP of FSM was more susceptible to the change of on/off ratio.The optimum aeration intensities of FSM and HFM were 1.20 m3/(m2·h)and 0.60 m3/(m2 ·h)respectively.The critical flux of both membranes were in the range of 20 ~25 L/(m2·h)but compared with HFM,the range of FSM was relatively lower.In the MLSS range of 8 000~15 000 mg/L,the optimum operation MLSS of FSM was higher than that of HFM.In a project of A2/O-MBR project to treat the municipal wastewater with the capacity of 10 000 m3/d,the total invest-ment of the project using FSM was 42 million YUAN,the operation cost was 1.36 YUAN/m3 . While,if HFM was used in the same project,the total investment was 39 million YUAN,the op-eration cost was 1.1 9 YUAN/m3 .
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