CFD Analysis of the Effect of Baffle Plates on the Fluid Flow in an Anaerobic Sequencing Batch Reactor

Abstract

With the development of agro-industrial processes, the waste generation has increased. Fermentation of organic wastes has attracted considerable attention, as it is an effective production route of hydrogen and it reduces environmental organic pollution. In this work, a numerical study is presented, with the aim of optimizing an anaerobic sequencing batch reactor (ASBR) for biohydrogen production. The Computational Fluid Dynamics (CFD) technique was used to provide accurate results for the fluid flow, which directly influences the mass transfer, momentum, and hence the kinetics of the reactions involved. An Eulerian-Eulerian approach was applied to describe the flow of the phases, using the OpenFOAM code. The inclusion of baffles in the bioreactor was studied, to verify the configuration which provides higher mixing. It was found that the inclusion of a baffle with length equal to ¼ of the bioreactor radius caused the largest increase in the turbulent kinetic energy, with little effect on the pressure drop.