中空纤维帘式与平板式膜组件在浸没式MBR中的对比试用研究

COMPARATIVE PILOT TESTS ON A SUBMERGED MEMBRANE BIOREACTOR(MBR) SYSTEM OF HOLLOW-FIBER AND FLAT-SHEET MEMBRANE MODULE

选取两种不同结构类型的膜组件进行化工废水处理的中试应用研究,对比研究了MBR膜系统的最佳气水比、临界膜通量、膜系统的分离与处理效果以及膜的污染和清洗方式。中试结果表明,在该类废水处理中,中空纤维帘式膜组件的最佳气水比为24,平板式膜组件的最佳气水比为20;在同等曝气强度下,用流量阶梯法测得,中空纤维帘式膜组件的临界膜通量为20L·m-2·h-1,平板式膜组件的临界膜通量为25L·m-2·h-1;两组膜在处理和分离效果上相差不大;在抗污染性能上,平板式膜组件更具优势,而且平板式膜组件更容易通过物理清洗-空曝气的方式使膜通量得以部分恢复,用次氯酸钠(NaClO)溶液对膜组件进行化学清洗,均能获得较好的通量恢复效果。

Pilot waste water treatment tests were conducted through submerged membrane bioreactor （MBR） with two membrane modules namely hollow-fiber membrane module and flat-sheet membrane module. Comparative studies were also conducted with the two different MBR modules in terms of the optimal ratio of gas to permeated effluent, critical membrane flux, the quality of the permeate, membrane fouling and membrane cleaning. The results showed that the optimal ratio of gas to permeated effluent was 24 and 20 for hollow-fiber and flat-sheet membrane modules, respectively. The critical membrane flux, which was determined under the same aeration intensity, was 20 L·m^-2·h^-1 and 25 L·m^-2·h^-1 for hollow-fiber and flat-sheet membrane module respectively. There was no reasonable difference of the quality of permeate of the two modules. However, fiat-sheet module was more anti-fouling than hollow-fiber module; the flux recovery rate of flat-sheet module was larger than that of hollow-fiber module. Membrane flux of two modules could also be recovered by chemical cleaning with NaClO solution.