超滤处理微污染地表水的膜污染化学清洗研究

针对超滤处理微污染地表水时产生的膜污染,利用电镜扫描和能谱技术分析其膜丝内表面污染物的组份,并考察了几种化学清洗剂对污染膜的清洗效果。试验结果表明,膜丝内表面的污染层是由有机物、微生物和无机物组成,其中有机物覆盖着无机物,以有机污染为主;膜清洗宜先碱洗后酸洗;单一清洗剂中NaOH、NaC1O和H2O2均有较好的清洗效果,但并不能使膜通量完全恢复,而复合清洗剂H2O2+柠檬酸具有显著的清洗效果,膜通量恢复率高达98%。

Chemical Cleaning Membrane Fouling of UF for Treating Micro-polluted Surface Water

In view of membrane fouling of UF for treating micro-polluted surface water, fouling matters on inner surface of membrane were analyzed by SEM and EDS. Several chemical cleaning agents had also been investigated for removing membrane pollutants. Results showed that membrane pollutants consist of organic, microorganism and inorganic matter, with organic matter as dominating pollutants and lying on top of inorganic fouling. Agents including NaOH, NaClO and H2O2 could achieve a better cleaning effect respectively, but cannot restore membrane flux totally. Alkaline agents should be used in advance of acidic ones. The combined cleaning agents with H2O2 and citric acid showed satisfying effect which made membrane flux being restored up to 98%.