投加粉末活性炭对一体式膜-生物反应器膜污染的影响研究

Study on effect of powdered activated carbon on the fouling in a submerged membrane bioreactor

通过试验考察了粉末活性炭(PAC)对一体式膜-生物反应器中膜污染的影响.在2种类型的污泥(膨胀污泥和非膨胀)中,投加适量PAC可以减轻膜污染,表现为临界膜通量的提高和连续运行中膜污染增长速率的降低.当污泥性质和浓度不同时,最佳PAC投加范围亦不同.PAC投量过大会引起临界通量下降.PAC的投加显著降低了混合液中溶解性物质的浓度,减轻了溶解性物质的吸附和膜孔堵塞污染,并改善了絮体结构.污泥比阻与污泥混合液膜过滤性能之间有很好的相关性,可作为污泥混合液膜过滤性能的快速评价指标.

The effect of powdered activated carbon （PAC） on the fouling in a submerged membrane bioreactor was investigated. For the two kinds of activated sludge （bulking sludge and non-bulking sludge）, the addition of PAC could alleviate membrane fouling, as the increased critical flux and reduced transmembrane pressure （TMP） during long-term run. The optimal PAC dose was different upon sludge characteristics and concentration, however, overdosed PAC led to a decrease of critical flux. The addition of PAC remarkably reduced the amount of solutes, which caused membrane fouling by adsorbing to the membrane or plugging the pores, as well as improve the sludge floc structure. The specific resistance to filtration （SRF） of sludge was found to have a good correlation with membrane fdterability of mixed liquor. SRF can be used as a convenient index for measurement of membrane filterability.