Experimental investigation and CFD simulation of turbulence effect on hydrodynamic and mass transfer in a packed bed airlift internal loop reactor

The experimental investigation and its simulation using computational fluid dynamics (CFD) of hydrodynamic and mass transfer for two phase bubbly flow in a split cylindrical airlift reactor were carried out. The turbulence influences on mass transfer and hydrodynamic parameters were considered when packing was installed in the riser zone. Further, CFD was properly able to simulate hydrodynamic and mass transfer in a bubbly flow. Packing existence in an airlift reactor increased gas hold-up and decreased liquid velocity. The lower velocity increased the delay time (residence time), which increased the mass transfer. Since there is random and erratic movement of liquid bulk layers and dynamic fluctuations in a packed bed airlift reactor so, Reynolds number increased and resulted in mass and momentum transfer enhancement. In an unpacked reactor, the superficial gas velocity enhancement changed the flow regime from homogenous to transition while in packed bed reactor the homogenous flow regime was only observed.