Simulations of unsteady flows with adsorption equilibrium in dynamic axial compression column

Abstract

Simulated moving bed chromatography process, which is a multicolumn chromatography process, has been used in various industrial applications. Dynamic axial compression columns are key elements in simulated moving beds, and their flow characteristics are worth exploring using state-of-the-art numerical methodologies. In this study, new fluid distributors for the dynamic axial compression column were designed and fabricated based on mass conservation in fluid mechanics and the computer-aided design in the preliminary stage. Computational fluid dynamics was employed to resolve the flow field, and the numerical chromatograms were validated by laboratory experiments. For the computational fluid dynamics–based simulation of flow in the dynamic axial compression, the transient laminar flow fields were described by the momentum and species transport equations with Darcy’s law to model the porous zone in the packed bed. In addition, reverse engineering processes were applied to obtain the unknown physical parameters, such as viscous resistance and adsorption equilibrium coefficients. Moreover, including the adsorption equilibrium equation in the fundamental governing equations made the simulated results agree with the experimental data in chromatograms, providing a more feasible result for practical applications.