浸没板式MBR处理生活污水造成膜堵塞的关键因素

采用浸没板式膜生物反应器对大学学生宿舍与食堂混合排水进行处理，试验系统应用A/O工艺，设置硝化槽与反硝化槽，日处理生活污水4 m3.当进水ρ(BOD₅)和ρ(COD_Cr)分别为90～450和120～900 mg/L时，出水ρ(BOD₅)和ρ(CODCr)分别为5～25和8～45 mg/L，去除率均较高.同时对膜污染进行了试验研究，阐述了ρ(MLSS)，污泥粒径分布以及原水成分造成膜污染的机理.发现污泥粒径分布随ρ(MLSS)变化而发生改变，当ρ(MLSS)达到20.000 g/L以上时，污泥粒径明显减小，同时可导致膜污染的细微颗粒分布相对增高，这一现象得到ρ(MLSS)超过20.000 g/L时膜污染加剧的试验验证. 

The Mechanism of Membrane Fouling on Submerged Flat Membrane MBR Treating of Domestic Wastewater

A test with submerged flat membrane bioreactor (MBR) to treat the mixed wastewater from dormitory and the dining room of university was carried out. The experiment system applied A/O process with nitrification tank and denitrification tank, with daily treatment of 4 m3. The results showed that with BOD₅ concentration of 90～450 mg/L and COD_Cr concentration of 120～900 mg/L in the influent, the effluent BOD₅ concentration of 5～25 mg/L and COD_Crconcentration of 8～45　mg/L could be resulted, showing high removal efficiency. Meanwhile, the membrane fouling was studied, and the mechanism of membranefouling affected by MLSS, size distribution of sludge and composition of raw water revealed. It is found that the diameter of sludge particles changes with theMLSS. When MLSS is higher than 20.000 g/L, sludge particles diameter descends in evidence. Also, more small particles which can result in membrane foulingare resulted in. This phenomena was proved by experiment of membrane fouling when MLSS higher than 20.000 g/L.