A comparative study on membrane fouling alleviation mechanisms by using nanoscale Fe3O4 and poly dimethyldiallylammonium chloride

作者：Zhou, Jia-heng; Jiang, Sheng-feng; Yu, Hao-cheng; Wu, Chang-hua; Zeng, Tao; Zhou, Yun-cheng; Hong, Qian-kun; Wang, Hong-yu^*

来源：Environmental Technology, 2020, 41(12): 1477-1485.

DOI：10.1080/09593330.2018.1538260

• Membrane fouling
• nanoscale Fe3O4
• dehydrogenase activity
• soluble microbial products (SMP)
• interspecies electron transfer

Membrane bioreactor (MBR) has become a promising technology for wastewater treatment. However, membrane fouling frequently occurred which greatly increased operational expense. Two different membrane fouling alleviation mechanisms were explored in this study. Addition of poly dimethyldiallylammonium chloride (PDMDAAC) facilitated formation of flocs-flocs aggregates, which were more adaptable to the changing environment, resulting in less soluble microbial products (SMP) secretion. However, PDMDAAC lose activity gradually, and had a less sustainable effect on membrane fouling alleviation. Nanoscale Fe3O4 was applied to alleviate membrane fouling, and membrane sustainable filtration cycle extended 2-fold compared to the control group. Results showed that dehydrogenase activity in the reactor with optimal addition of nanoscale Fe3O4 increased 2.86 +/- 0.11 times compared to control group. SMP (especially tryptophan protein-like substances) decreased to 9.79 +/- 1.34 mg L-1 with the addition of nanoscale Fe3O4, which was lower than that in the control group (15.31 +/- 0.53 mg L-1). It's speculated that nanoscale Fe3O4 performed as conductive material, which intensified interspecies electron transfer. The sludge dehydrogenase activity was then enhanced, which facilitated the utilization and microbial degradation of SMP, suppressing membrane fouling consequently.

• 出版日期2020-5-24
• 单位浙江工业大学