低压膜净水过程中的膜污染控制

Membrane Fouling Control of Low Pressure Membrane in Water Purification Process

近年来,低压膜(LPM)技术在饮用水处理和废水回用等领域的应用越来越广泛,但膜污染会消耗更多的能源,增加运行和维护费用,是制约其发展的瓶颈。膜前预处理技术与低压膜组合工艺已被广泛用在减轻膜污染、提高污染物去除率和膜通量等方面。膜前预处理技术可以改变水中分子与颗粒物的尺寸,影响污染物之间和污染物与膜之间的相互作用关系,抑制不良微生物的生长或去除可生物降解的污染物,从而影响膜过滤性能。此外,采用适当的操作方式(如运行方式,反冲洗,曝气)也可以有效地减轻膜污染。该文介绍了近年来国内外各种预处理技术和操作条件在控制低压膜污染的最新研究进展,并阐述了其在缓解膜污染方面的机理。

The application of low pressure membrane （LPM） in drinking water treatment and wastewater reuse has become more popular in the past years. But membrane fouling would cost more energy, operating and maintain expense. Integration of pretreatment with LPM filtration has been widely applied to reduce membrane fouling and increase the removal of certain aquatic contaminants. In principle, pretreatment of raw water can impact membrane filtration in three ways： altering contaminant size distribution, changing mutual affinities of contaminants or their affinities to membrane surface, and suppressing undesirable microbial growth or removing biodegradable contaminants. Moreover, modest operation methods （running modes, backwashing, and aeration） can effectively obtain the fouling reduction. In the paper, the latest research progress at home and abroad on the pretreatment technology and operation methods controlling low-pressure membrane fouling in recent years were introduced, and the mechanism of mitigating membrane fouling was described in detail.