正渗透膜生物反应器(OMBR)作为一种新兴的技术,有很好的应用前景,但是关于其膜污染的研究尚且不多.本文研究了在OMBR运行过程中膜表面所形成滤饼层的性质.结果显示,在OMBR运行初期,大粒径颗粒先沉积在膜表面;随着运行,生物反应器内的颗粒变小,小的颗粒沉积在膜表面.滤饼层韧性比较强,很容易将其从膜表面冲刷下来.扫描电镜显示滤饼层与正渗透膜接触一侧很光滑,冲洗后的膜只有少量污染物残留.这是由于正渗透膜表面粗糙度小,孔隙小,污染物很难进入膜孔中,滤饼层与膜之间连接不紧密.滤饼层中51%重量组分的物质是有机物,其余是无机污染物.通过红外测定,主要的有机污染物是多糖和蛋白质,是生物聚合物的主要成分.通过能量散射X射线分析仪(EDX)显示主要无机元素是Si、Ca、Mg、Al和Fe.综上,正渗透膜生物反应器产生的膜污染易清洗,要减少其膜污染需要控制生物聚合物和无机污染物的量.%Osmosis membrane bioreactor (OMBR), as a new emerging technology, has a bright prospect in wastewater treatment, while the membrane fouling behavior of OMBR has not been explored.The characterization of the cake layer formed in OMBR was studied.The results indicate that the bigger particles in activated sludge would deposit on the membrane earlier.As the OMBR running, the particles in the bioreactor turned small, and then the smaller particles would deposit on the membrane.The cake layer formed on the membrane has well strength and it was easy to flush away from the membrane.The SEM analysis exhibited that the side contacted to the FO membrane of the cake layer was very smooth and the flushed FO membrane was very clean with little foulant on it.This is because the osmosis membrane has small roughness and tiny pores, so the foulant can't enter into the membrane pores and connected loosely with FO membrane.In the cake layer, 51% weight percent was biofoulant and 49% weight was inorganic foulant.Biofoulant and inorganic matter have strong impacts on membrane fouling process.The main components of biopolymers were identified as proteins and polysaccharide materials by the FTIR.The examination by EDX demonstrated that Si, Ca, Mg, Al and Fe were the major inorganic elements in fouling cake.Therefore, during the operation of OMBRs, the biopolymers and inorganic matter in the bioreactor should be controlled to minimize membrane fouling.
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