title: Hydrodynamic optimization of membrane bioreactor by horizontal geometry modification using computational fluid dynamics.
abstract: Geometry property would affect the hydrodynamics of membrane bioreactor (MBR), which was directly related to membrane fouling rate. The simulation of a bench-scale MBR by computational fluid dynamics (CFD) showed that the shear stress on membrane surface could be elevated by 74% if the membrane was sandwiched between two baffles (baffled MBR), compared with that without baffles (unbaffled MBR). The effects of horizontal geometry characteristics of a bench-scale membrane tank were discussed (riser length index Lr, downcomer length index Ld, tank width index Wt). Simulation results indicated that the average cross flow of the riser was negatively correlated to the ratio of riser and downcomer cross-sectional area. A relatively small tank width would also be preferable in promoting shear stress on membrane surface. The optimized MBR had a shear elevation of 21.3-91.4% compared with unbaffled MBR under same aeration intensity.
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, THU-Beijing Origin Water Joint Research Center for Environmental Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Xiaoxu
authors.initials: X
authors.lastname: Yan
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, THU-Beijing Origin Water Joint Research Center for Environmental Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wu
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, THU-Beijing Origin Water Joint Research Center for Environmental Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Jianyu
authors.initials: J
authors.lastname: Sun
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, THU-Beijing Origin Water Joint Research Center for Environmental Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liang
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, THU-Beijing Origin Water Joint Research Center for Environmental Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Resource and Environment, University of Chinese Academy of Science, Beijing 100049, China.
authors.forename: Kang
authors.initials: K
authors.lastname: Xiao
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, THU-Beijing Origin Water Joint Research Center for Environmental Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China. Electronic address: xhuang@tsinghua.edu.cn.
authors.forename: Xia
authors.initials: X
authors.lastname: Huang
mesh_terms: D019149:Bioreactors; D003198:Computer Simulation; D005374:Filtration; D057446:Hydrodynamics; D008567:Membranes, Artificial; D008863:Microspheres; D008962:Models, Theoretical; D011137:Polystyrenes / Q000737:chemistry; D015203:Reproducibility of Results; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties; D062065:Wastewater; D018508:Water Purification / Q000379:methods*
chemical_list: D008567:Membranes, Artificial; D011137:Polystyrenes; D062065:Wastewater
keywords: Computational fluid dynamics; Geometry optimization; Hydrodynamics; Membrane bioreactor; Membrane surface shear