不同超滤组合工艺处理南水北调水源水效能及膜污染

Treatment Efficiency and Membrane Fouling Analysis of Different Ultrafiltration Combined Processes for Source Water of the South-to-North Water Diversion Project

为了探究不同超滤组合工艺对南水北调水源水的处理效能,开展了不同超滤组合工艺研究。考察了“混凝沉淀-臭氧/活性炭-超滤”全流程中试工艺对浊度、色度、CODMn、UV254等常规水质指标的去除效果,探究了直接超滤、混凝沉淀-超滤以及混凝沉淀-臭氧/活性炭-超滤这三种不同运行工况下的跨膜压差和膜污染情况。结果表明,混凝沉淀工艺对浊度和色度有着较高的去除率,但对有机物的去除效果较差;相比常规混凝沉淀工艺,混凝沉淀-臭氧/活性炭工艺对有机物的去除效能更好;超滤作为最后一道屏障,可进一步强化组合工艺对浊度、色度和有机物的去除。不同组合工艺工况下,标准堵塞和滤饼层过滤是拟合效果更好的膜污染类型;原水直接超滤时膜污染增速较快,膜前常规和深度处理工艺的组合可有效缓解超滤膜污染。

To explore the treatment efficiency of different ultrafiltration(UF) combined processes on the source water of the South-to-North Water Diversion Project,a study on various UF combined processes was conducted.The study examined the removal efficiency of conventional water quality parameters such as turbidity,color,CODMn,UV254,etc.,by different units combination of the coagulation sedimentation-ozone/activated carbon-UF full-scale process.Furthermore,the transmembrane pressure(TMP) and membrane fouling under three different operational conditions:direct UF,coagulation sedimentation-UF,and coagulation sedimentation-ozone/activated carbon-UF were investigated.The results indicated that the coagulation sedimentation process exhibited a higher removal rate for turbidity and color,but a relatively poor removal efficiency for organic matter.In comparison to conventional coagulation sedimentation processes,the coagulation sedimentation-ozone/activated carbon process demonstrated better removal efficiency for organic matter.UF,serving as the final barrier,could further enhance the removal of turbidity,color and organic matter in the combined process.Under different combined process conditions,standard blocking model and cake filtration model were identified as the predominant types of membrane fouling with better fitting effects.Membrane fouling increased rapidly during direct UF of raw water,whereas the combination of conventional and advanced treatment processes effectively mitigated UF membrane fouling.