Using inorganic coagulants to control membrane fouling in a submerged membrane bioreactor
Using inorganic coagulants to control membrane fouling in a submerged membrane bioreactor
复制标题
DOI：
10.1016/j.desal.2005.11.026
复制
发表时间：
2006-10
期刊：
影响因子：
9.9
通讯作者：
Jinling Wu;Futai Chen;Xia Huang;W. Geng;X. Wen
中科院分区：
文献类型：
--
作者：
Jinling Wu;Futai Chen;Xia Huang;W. Geng;X. Wen
研究了单体混凝剂和聚合混凝剂[Al2(SO4)3、FeCl3、聚合氯化铝（PAC）和聚合硫酸铁（PFS）]加入后活性污泥混合液的性能（比过滤阻力、絮凝粒径、上清TOC和zeta电位）的变化。结果表明，高分子混凝剂对混合液的过滤效果优于单体混凝剂。进一步研究发现，高分子混凝剂可以为有机颗粒和污泥絮凝体提供更多的正电荷，增强电荷中和功能，从而提高上清有机物的去除率，增大污泥絮凝体的粒径。为此，在浸没式膜生物反应器（MBR）中加入聚合混凝剂PAC、PFS和PAFC，研究其对膜污染的控制效果。高分子混凝剂可以通过降低初始TMP和TMP的增加速率来控制膜污染。高分子混凝剂对膜污染的控制有三个作用：抑制凝胶层的形成、减缓污染物的发展和去除膜表面的稳定污染物。在所选混凝剂中，PFS对膜污染的控制效果最好，最佳投加量为1.05 mM Fe。如果在MBR运行前添加混凝剂，可以获得较好的效果。
Changes of properties (specific filtration resistance, floc size, supernatant TOC and zeta potential) of activated sludge mixed liquor after monomeric and polymeric coagulants [Al2(SO4)3, FeCl3, PAC (polymeric aluminum chloride) and PFS (polymeric ferric sulfate)] addition were studied in this paper. It was found that polymeric coagulants had a better effect on filterability enhancement of mixed liquor than monomeric coagulants. Further research found that the reason was that polymeric coagulants could supply more positive charges for organic particles and sludge flocs, and enhance the functions of charge neutralization, which resulted in higher removal of supernatant organic matter and enlargement of sludge floc size. Thus, polymeric coagulants (PAC, PFS and PAFC) were added in a submerged membrane bioreactor (MBR) and the effect on membrane fouling control was investigated. It was found that polymeric coagulants could control membrane fouling by reducing the initial TMP and the TMP increase rate. Three functions of polymeric coagulants on membrane fouling control were supposed: restraining the formation of gel layer, decelerating the development of foulants and removing stable foulants from the membrane surface. Among the selected coagulants, PFS was the most effective in controlling membrane fouling and the optimal dose was 1.05 mM Fe. If coagulant was added before the MBR was run, a better effect could be obtained.