平板膜污泥浓缩工艺中污染膜的膜清洗方式

Membrane Cleaning Patterns of Fouled Membrane for Flat-Sheet Membrane Sludge Thickening Process

该文研究了平板膜污泥浓缩工艺中污染膜的清洗，分析了不同种类、不同浓度化学药剂的清洗效果，重点评估了膜通量恢复率、膜表面形态、临界通量等性能。结果表明NaClO为最有效清洗药剂，清洗后膜水通量恢复最显著，膜表面孔隙率恢复最高，NaOH药剂不适宜于该工艺中膜的清洗。此外，试验确定0．1％草酸和1％NaClO的组合清洗方式为污泥浓缩工艺中膜清洗的最佳清洗方式，经组合清洗后的膜表面形态基本完全恢复，临界通量可高达32～35L／m2·h。

The membrane cleaning in process using flat-sheet membrane for thickening sludge was studied. The cleaning effect under different chemical cleaning agents and concentration was analyzed. Membrane flux recovery rate, the surface morphology and critical flux were assessed. The results show that NaClO is the most effective cleaning agent because the membrane water flux and surface porosity can be effectively recovered. Furthermore, NaOH is found to be unfit for the membrane cleaning in this process. In addition, it is found that the combined cleaning mode comprised of 0.1% oxalic acid and 1% NaClO is taken as the best membrane cleaning method for flat-sheet membrane sludge thickening process. After combined cleaning, the membrane surface morphology can be almost completely recovered and the critical flux is 35 ~ 38 L/m2· h.