Potential effects of loading nano zero valent iron discharged on membrane fouling in an anoxic/oxic membrane bioreactor

Lijie Zhou; Weiqin Zhuang; Xin Wang; Ke Yu; Shufang Yang; Siqing Xia

doi:10.1016/j.watres.2017.01.007

Potential effects of loading nano zero valent iron discharged on membrane fouling in an anoxic/oxic membrane bioreactor

Water Res. 2017 Mar 15:111:140-146. doi: 10.1016/j.watres.2017.01.007. Epub 2017 Jan 3.

Authors

Lijie Zhou¹, Weiqin Zhuang², Xin Wang³, Ke Yu⁴, Shufang Yang⁵, Siqing Xia⁶

Affiliations

¹ State Environmental Protection Key Laboratory of Drinking Water Source Management and Technology, Shenzhen Key Laboratory of Drinking Water Source Safety Control, Shenzhen Key Laboratory of Emerging Contaminants Detection & Control in Water Environment, Shenzhen Academy of Environmental Sciences, Guangdong Shenzhen 518001, China; State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
² Department of Civil and Environmental Engineering, University of Auckland, Auckland 1142, New Zealand.
³ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
⁴ School of Environment and Energy, Peking University Shenzhen Graduate School, Guangdong Shenzhen 518055, China.
⁵ Shenzhen Municipal Design & Research Institute Co., Ltd, 3007 West Sungang Road, Guangdong Shenzhen 518029, China.
⁶ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China. Electronic address: [email protected].

PMID: 28068534
DOI: 10.1016/j.watres.2017.01.007

Abstract

A laboratory-scale submerged anoxic-oxic membrane bioreactor for municipal wastewater was operated to investigate the potential effects of loading suspended nano zero valent iron (nZVI, 25 and 50 mg/L) discharged on the membrane fouling. nZVI transformed rapidly into Feⁿ⁺, generated reactive oxygen species (ROS) and caused oxidative stress. This result rapidly led to the cell lysis and bacteria death, and further resulted in the decrease of biomass and extracellular polymeric substances (EPS). nZVI also thinned the membrane fouling layer. But nZVI had no obvious effects on activated sludge particle size, EPS molecule weight distribution and VOCs constitution of membrane foulant. Additionally, nZVI released Feⁿ⁺ and mitigated the inorganic (mainly Si element) fouling through Feⁿ⁺ flocculation. Consequently, membrane fouling mitigation with nZVI discharged was mainly due to oxidative stress to bacteria and Feⁿ⁺ flocculation of nZVI.

Keywords: Membrane bioreactor; Membrane fouling; Nano zero valent iron (nZVI); Reactive oxygen species.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bacteria / metabolism
Bioreactors / microbiology*
Iron / metabolism*
Membranes, Artificial
Sewage / microbiology

Substances

Membranes, Artificial
Sewage
Iron