Understanding natural organic matter fouling in low-pressure membrane filtration
Understanding natural organic matter fouling in low-pressure membrane filtration
复制标题
了解低压膜过滤中的天然有机物污染
DOI：
10.1016/j.desal.2004.11.030
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发表时间：
2005
期刊：
影响因子：
9.9
通讯作者：
J. Lozier
中科院分区：
文献类型：
--
作者：
Nohwa Lee;G. Amy;J. Lozier
天然水中的天然有机物（NOM）是低压膜污染的主要原因。膜污染的影响主要来自于纳米粒子的特性及其与膜的相互作用。本研究测试了三种不同的水源；河流水、污水处理厂二次出水及DOC和腐殖质含量高的水。选取了三种不同类型的低压平板膜（MF和UF）作为等效模拟商用中空纤维膜，进行了无端搅拌池过滤。从水源表征上看，通过SEC-DOC/UV分析，Scottsdale污水处理厂二级出水中胶体和/或大分子等高分子量化合物含量较高，且各膜过滤通量均呈明显下降趋势。与白河水相比，坦帕水含有相对较少的高分子量化合物，通量明显下降。这可能是由于其DOC含量比其他水源高出三倍以上。因此，含有高胶体和大分子以及高DOC含量的水在低压膜污染中是非常成问题的。反冲洗流的SEC-DOC/UV光谱结果表明，水力可逆污染物是高分子量化合物，这些分子可能通过在膜表面形成饼层而导致通量显著下降。
Natural organic matter (NOM) in natural water is responsible for significant organic fouling of low pressure membranes. Membrane fouling can be affected by the characteristics of the NOM and its interaction with the membranes and their associated properties. Three different water sources were tested for this study; river water, wastewater treatment plant secondary effluent and water with high content of DOC and humic substances. Three different types of low pressure flat sheet membranes (MF and UF) were selected which are equivalent simulation of commercial hollow fiber membranes, and dead-end, stirred cell filtrations were performed. From the water source characterization, Scottsdale WWTP secondary effluent has high content of high molecular weight compounds corresponding to colloids and/or macromolecules by SEC-DOC/UV and showed significant flux decline in all of membrane filtration. Tampa water contain relatively less high molecular weight compounds and showed significant flux decline comparing to White River water. This may be due to over three time higher DOC content than other water sources. Thus, the water containing high colloids and macromolecules as well as high DOC content is very problematical in low-pressure membrane fouling. SEC-DOC/UV spectrum of backwashed stream proved that hydraulically reversible foulants are high molecular weight compounds and those molecules are likely to cause significant flux decline by cake layer formation on membrane surface.