title: Structure and distribution of inorganic components in the cake layer of a membrane bioreactor treating municipal wastewater.
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.
authors: 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.
authors: Lijie
authors: L
authors: Zhou
authors: 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.
authors: Siqing
authors: S
authors: Xia
authors: Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720-1710, USA.
authors: Lisa
authors: L
authors: Alvarez-Cohen
mesh_terms: D019149:Bioreactors; D007287:Inorganic Chemicals / Q000737:chemistry*; D008567:Membranes, Artificial; D012822:Silicon Dioxide / Q000737:chemistry; D062065:Wastewater; D018508:Water Purification / Q000379:methods*
chemical_list: D007287:Inorganic Chemicals; D008567:Membranes, Artificial; D012822:Silicon Dioxide; D062065:Wastewater
keywords: BCR sequential extraction; Cake layer; Inorganic distribution; Membrane bioreactor; SiO(2)–Al(2)O(3) crystal particles