Modelling the Hydrodynamics of Gas-Liquid Packed Beds via Slit Models: A Review

Abstract

Packed bed columns are intensively used as multiphase contactors and reactors in chemical, biochemical, and petrochemical industries. Due to two-phase through the packed beds, the performance of multiphase contactors depends on the complex interaction of the interphase mass transfer, thermodynamics and hydrodynamics. Under reaction conditions, the intraparticle mass transfer and reaction kinetics have additional considerable impact on the reactor performance. The inherent complexity of multiphase systems leaves many issues unresolved and leads to many inconsistencies and questionable approximations, especially in the modelling of multiphase flow. Multiphase flow modelling in packed beds is a complicated task because of the difficulty incorporating the complex geometry into the flow equations, and the difficulty in accounting for the gas-liquid interactions in the presence of complex fluid-particle (e.g., partial wetting) contacting. This review focuses on recent advances made in the modelling of the hydrodynamics of two-phase downflow and counter-current flow in packed beds via two-fluid models coupled with slit and double slit phenomenological approximations relating the mutual three phase hydrodynamic interactions.