基于平行因子分析的藻菌共生膜污染机制研究

Investigation on membrane fouling of microalgae-fungus/bacteria consortia by parallel factor analysis method

基于不同藻菌共生体系(微藻真菌、微藻细菌)处理畜禽养殖废水,采用死端过滤的超滤杯实验测试不同体系(A.纯微藻体系;B.微藻真菌体系;C.微藻细菌体系)混合液在超滤过滤中的污染状况,研究膜污染形成机制.实验结果表明,B、C组的通量衰减速度明显低于A组,A组膜污染模型以标准堵塞和滤饼层为主,而B、C组膜污染与标准堵塞、中间堵塞和滤饼层模型均有很高的拟合度.A组混合液粒径在1~30μm范围内比B和C组占比更多,在30~1000μm范围分布较少,导致膜孔堵塞更快,形成的滤饼层更为紧密,膜污染更严重.膜清洗液EEMs PARAFAC结果表明,膜面有机污染物主要为色氨酸和酪氨酸类蛋白质.B和C组藻菌共生作用大大减少了EPS类物质的产量,尤其是色氨酸类蛋白质,从而减轻了膜污染状况.

Microalgae-fungus consortia and microalgae-bacteria consortia were utilized for the treatment of digested swine manure wastewater,and their influence on ultrafiltration membrane fouling was investigated using filtration cell with dead end filtration mode.Three kinds of mixture from different groups(A.pure microalgae system;B.microalgae-fungal system;C.microalgae-activated sludge system)were tested for membrane fouling conditions.The results showed that the flux decreasing rates of group B and C were lower than that of group A.he membrane fouling mechanism for group A was dominated by standard blocking and cake filtration.However,the membrane fouling mechanisms for group B and C had a high degree of fitting with standard blocking,intermediate blocking and cake filtration models.The mixture from group A had a larger proportion in the particle size distribution of 1~30μm and less among the range of 30~1000μm in comparison with those of group B and C,resulting in faster blocking of the membrane pores,looser cake layer and more serious membrane fouling for group A.The analysis of EEMs coupled with PARAFAC modeling of desorbed solutions indicated that the organic pollutants on the membrane surface were mainly tryptophan,tyrosine proteins and polysaccharides.Both microalgae-fungus consortia and microalgae-bacteria consortia can form harmonious symbiotic relationship,which greatly reduced the EPS production,especially tryptophan proteins that contributes to the mitigation of membrane fouling.