预涂动态膜-生物反应器处理人工废水的试验研究

以公称孔径为1 μm的聚丙烯无纺布(NWF)为基膜,分别以粉末状活性炭、粉末状活性炭及聚合氯化铝为预涂剂,制作预涂动态膜膜组件,组成预涂动态膜-生物反应器处理人工废水.结果表明,预涂动态膜-生物反应器出水COD值低且稳定,粉末状活性炭预涂膜-生物反应器出水COD平均值为49 mg/L,粉末状活性炭及聚合氯化铝预涂膜-生物反应器出水COD平均值为29 mg/L,而NWF-膜生物反应器出水COD为54 mg/L.膜生物反应器对污染物质的去除虽然主要依靠活性污泥混合液,但附着在基膜上的动态膜的吸附、混凝作用也能去除部分污染物质.预涂膜能减少及防止污染物质向膜材料表面和内部扩散,减轻膜污染,使预涂动膜-生物反应器显示出一定的耐污染性能.但粉末状活性炭粒径过小,影响粉末状活性炭预涂动态膜-生物反应器的出水浊度(平均值为3.3 NTU);而粉末状活性炭与聚合氯化铝形成的预涂动态膜,在提高COD去除效率的同时,能减少活性炭对出水浊度(平均值为2.3 NTU)的影响,保证出水水质.

Synthetic wastewater treatment with pre-coating dynamic membrane bio-reactor

The pre-coating dynamic membrane bioreactor(PDMBR) was composed of membrane model made of polypropylene (PP) non-woven fiber (NWF) with nominal diameter 1 μm and pre-coated with powdered activated carbon (PAC) and with both of PAC and poly-aluminium chloride. The PDMBR was used for synthetic wastewater treatment. The experimental results showed that the effluent COD from PDMBR is low and stable, the average COD of effluent from PAC-MBR is 49 mg/L, and the average COD from MBR pre-coated with PAC and poly-aluminium chloride is 29 mg/L, but COD of effluent from NWF-MBR is 54 mg/L. It illuminates that pollutants removal mainly depends on mixed activated sludge, but absorption and flocculence of dynamic membrane attached on the model can also remove some pollutants. Pre-coating dynamic MBR can reduce and prevent pollutants diffusing into the surface and interior of the primary membrane so as to mitigate membrane fouling and to make PDMBR have antifouling performace. If particles diameter of PAC is too small, the effluent turbidity (average is 3.3 NTU) from PDMBR will be effected. However, the precoating dynamic membrane formed by PAC and poly-aluminium chloride can not only increase the efficiency of COD removal, but also reduce the effect on effluent turbidity (average is 2.3 NTU) by activated carbon and can ensure good effluent quality.