Hydrodynamic Optimization of Membrane Bioreactors Using Baffles with Different Geometries by Computational Fluid Dynamics

Broadly bioreactors are applied for wastewater treatment, bothe industrial and municipal.Baffles are one of the most importance key component in an airlift membrane bioreactor (MBR), which could increasing membrane surface shear for fouling control. In order to obtain an optimal hydraulic condition of the reactor, the effects of baffle geometry was systematically discovered in this study. Computational fluid dynamics (CFD) was used to peruse the hydrodynamics in a bench-scale airlift flat sheet MBR with various baffle geometries. Several geometrical configurations were considered for the membrane bioreactor. Validated simulation results showed that converging diverging sharp baffles were more effective in elevating membrane surface shear than simple and converging diverging smooth baffles. Comparison of the velocities of the liquid and gas phases in the Riser part of the airlift reactor for three different geometries shows that at a constant aeration rate the maximum velocity occurs in the throat of the converging diverging sharp baffle.

Keywords:

Membrane Bioreactors , Computational fluid dynamics , shear stress , Converging Diverging Baffle , Simple Baffle , fouling