Structure and distribution of inorganic components in the cake layer of a membrane bioreactor treating municipal wastewater

Lijie Zhou; Siqing Xia; Lisa Alvarez-Cohen

doi:10.1016/j.biortech.2015.08.026

Structure and distribution of inorganic components in the cake layer of a membrane bioreactor treating municipal wastewater

Bioresour Technol. 2015 Nov:196:586-91. doi: 10.1016/j.biortech.2015.08.026. Epub 2015 Aug 14.

Authors

Lijie Zhou¹, Siqing Xia², Lisa Alvarez-Cohen³

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720-1710, USA.
² 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: siqingxia@gmail.com.
³ Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720-1710, USA.

PMID: 26298402
DOI: 10.1016/j.biortech.2015.08.026

Abstract

A laboratory-scale submerged anoxic-oxic membrane bioreactor treating municipal wastewater was operated to investigate the structure and distribution of the inorganic cake layer buildup on the membrane. BCR (European Community Bureau of Reference) sequential extraction, X-ray photoelectron spectroscopy (XPS), and both map and line scan of energy-dispersive X-ray analysis (EDX) were performed for cake layer characterization. BCR results showed that Si, Al, Ca, Mg, Fe, and Ba were the predominant inorganic elements in the cake layer, and they occurred mostly as crystal particles. Crystal SiO2 was the dominant inorganic compound while Ca in the form of CaSO4 (dominant) and CaCO3 were also present, but exerted little effect on the cake layer structure because most of these compounds were deposited as precipitates on the reactor bottom. EDX results indicated that Si and Al accumulated together along the cross-sectional cake layer in the form of Si-Al (SiO2-Al2O3) crystal particles.

Keywords: BCR sequential extraction; Cake layer; Inorganic distribution; Membrane bioreactor; SiO(2)–Al(2)O(3) crystal particles.

Publication types

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

MeSH terms

Bioreactors*
Inorganic Chemicals / chemistry*
Membranes, Artificial*
Silicon Dioxide / chemistry
Wastewater*
Water Purification / methods*

Substances

Inorganic Chemicals
Membranes, Artificial
Waste Water
Silicon Dioxide