CFD modeling and simulation of gas-phase extraction processes in fluidized bed reactor

Recently, the gas-phase organic ligand extraction of metals from low-grade sources using the fluidized bed reactor (FBR) technique has garnered significant attention owing to its simplicity and advantages in reducing energy costs. In this study, a computational fluid dynamics (CFD) coupled model including a three-phase Eulerian model, kinetic theory of granular flow model, and reaction kinetics model was proposed to investigate gas-phase extraction processes encountered in an FBR. The developed three-phase CFD coupled model was first validated by comparing the obtained simulation results with the experimental data of cumulative iron extraction at different reaction temperatures and the classical calculated data of the pressure drop. Subsequently, the effects of the inlet gas velocity and particle phase holdup on the extraction were studied. Accordingly, both particle fluidization behaviors and extractive reaction kinetics characteristics were obtained. The simulation results indicated that the mentioned operating conditions significantly affected the distribution of particle phase holdup and subsequently influenced the cumulative iron yield through an extractive reaction. Furthermore, the developed CFD coupled model is beneficial for optimizing gas-phase extractive reaction process in FBRs.