浸入式短流程超滤膜生产工艺过程膜污染的形成与控制

Membrane Fouling Mechanism and Control Strategy for the Pilot-Scale Submerged PVC-UF Membrane Process

以江苏芦泾水厂膜技术改造工程为对象,从水质、膜工艺特征结合生产运行过程以及污染膜的清洗进行了分析,目的是了解膜污染的组分构成,评价不同清洗剂的清洗效果,获取较优的清洗顺序.结果表明,原水以憎水酸(HOA)和亲水组分(HIM)为主体,质量分数各占40.34%和28.48%.溶解性有机物(DOM)则以芳香性蛋白质Ⅱ类物质为主.工艺运行结果说明PVC合金膜能很好降低水中浊度至0.1 NTU,并部分截留DOM.膜污染是由无机离子和天然有机物共同作用造成.其中Ca和Si是膜污染的主要无机元素,而芳香性蛋白质Ⅱ类、SMP和富里酸类有机物均是造成膜污染的重要有机物.对采用不同清洗方法后的污染膜进行SEM表征发现,清洗的次序应先用盐酸清洗再用氢氧化钠清洗.

In this paper,Lujing water supply plant in Jiangsu was selected to carry out the investigation in order to understand the constitutes of the membrane fouling,comment on the membrane cleaning methods and obtain the proper cleaning sequences.In the experiments,water quality of the raw water was measured;membrane characteristics of the plant and membrane cleaning methods were thoroughly analyzed.The results indicated that the hydrophobic acids（HOA） and hydrophilic matters（HIM） are the major components in the raw water,40.34% and 28.48% respectively in mass fraction.EEM＇s results also demonstrated that aromatic protein Ⅱ are the main constitutes in the DOMs.In addition,the turbidity can reach around 0.1 NTU and the DOM can be removed partially by the PVC-UF membrane process during the water production.The constitutes of those emulations demonstrated that inorganic ions and NOM were both contributed to the membrane fouling.Ca and Si were the major inorganic contributors;aromatic protein Ⅱ,SMP and fulvic acid were the major organic ones.According to SEM observation the sequence of the membrane cleaning should be HCl first,then NaOH.