title: Hydraulic optimization of membrane bioreactor via baffle modification using computational fluid dynamics.
abstract: Baffles are a key component of an airlift membrane bioreactor (MBR), which could enhance membrane surface shear for fouling control. In order to obtain an optimal hydraulic condition of the reactor, the effects of baffle location and size were systematically explored in this study. Computational fluid dynamics (CFD) was used to investigate the hydrodynamics in a bench-scale airlift flat sheet MBR with various baffle locations and sizes. Validated simulation results showed that side baffles were more effective in elevating membrane surface shear than front baffles. The maximum average shear stress was achieved by adjusting baffle size when both front and side baffles were installed. With the optimized baffle configuration, the shear stress was 10-30% higher than that without baffles at a same aeration intensity (specific air demand per membrane area in the range of 0-0.45m(3)m(-2)h(-1)). The effectiveness of baffles was particularly prominent at lower aeration intensities.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Xiaoxu
authors.initials: X
authors.lastname: Yan
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Kang
authors.initials: K
authors.lastname: Xiao
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Liang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Lei
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liang
authors.affiliation: Beijing Origin Water Technology Co., Ltd, Beijing 102206, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Xue
authors.affiliation: Beijing Origin Water Technology Co., Ltd, Beijing 102206, China.
authors.forename: Kaichang
authors.initials: K
authors.lastname: Yu
authors.affiliation: Beijing Origin Water Technology Co., Ltd, Beijing 102206, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Guan
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, 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; D004867:Equipment Design; D057446:Hydrodynamics; D008567:Membranes, Artificial; D013314:Stress, Mechanical; D014865:Waste Disposal, Fluid / Q000295:instrumentation*
chemical_list: D008567:Membranes, Artificial
keywords: Airlift membrane bioreactor; Baffle; Computational fluid dynamics; Hydrodynamics; Membrane surface shear