Influence of solid loading on hydrodynamics of rectangular airlift bioreactor using CFD modeling

The hydrodynamic properties of a rectangular airlift bioreactor was investigated by three dimentional CFD modeling. The effect of solid on hydrodynamics of areobic bioreactor is rarely studied. In this work, the transient Eulerian multiphase model was applied to two- and three-phasereactors. The solution domain has been divided to 609783 unstructured tetrahedral meshes. The continuity and momentum equations were applied to all cells. Inert solid particles of 1 mm in diameter with 5, 10 % v/v loading and air with superficial velocities of 1-3 cm/s were cosidered as solid and gas media, repectively. It was observed that average gas holdup as well as liquid velocity decreased as a result of solid addition. The solids distribution was uniform along the reactor and there was no significant difference between solid holdups in the riser and the downcomer sections