运行条件对给水超滤膜装置工作周期的影响

Effect of operation mode on filtration period of ultrafiltration membrane reactor in water supply system

杂质的截留和有机物的吸附使超滤膜通量降低,频繁的化学清洗或更换膜组件使制水成本上升。试验比较了几种运行方式对超滤膜装置过滤性能的影响,探讨其对延长超滤膜装置运行的效果,研究结果表明:超滤膜装置的反冲洗不能等到膜组件污染物聚集稳定后再进行;在一定的过滤时间间隔后设定短暂的反冲洗,其效果优于膜组件污染稳定后的反冲洗;当膜清洗采用压缩空气和滤后水联合作用,对膜的过滤通量恢复和稳定,过滤周期的延长比相同条件下的滤后水反冲洗效果成倍提高;而膜组件的间歇式运行更利于膜通量的恢复和化学清洗频率的降低。因此,选择合适的操作运行方式,充分利用物理清洗的便利与经济性,具有技术和经济双重意义。

The interception of impurity and adsorption of organic matters causes the decrease of uhrafihration membrane flux, frequent chemical cleaning or membrane module replacement enhances the cost of water making The influences of different operation modes on filtration performance and operation effect of uhrafiltration membrane reactor were compared and discussed. The results showed that： it was too late to carry out the backwashing of ultrafiltration membrane reactor after the stable accumulation of pollutants in membrane module; the effect of a short time backwashing carried out after a certain time interval of filtration was better than that of the backwashing carried out after the stable accumulation of pollutants in membrane module; for the recovery and the stability of membrane filtration flux as well as the extension of filtration period, the cleaning effect of the membrane by the condensed air-filtered water combined process was many times better than that by the filtered water backwashing under the same condition. It could be seen that, intermittent operation of ultrafiltration module was favorable for the membrane flux recovery and the decrease of chemical cleaning frequency. Therefore, to select a suitable operation mode and make full use of the convenience and economy of physical cleaning has significant meaning in both technical and economical aspects.