Study of Pb2+ adsorption in a packed bed column of bentonite using CFD

• This MS investigated the Pb2+ adsorption in a packed bed of bentonite using CFD.
• A 2D two-phase model was successfully developed and applied to describe the Pb2+ adsorption.
• Advanced concepts of fluid flow and local mass transfer in packed beds were applied.
• The validated model results provided an in depth analysis of the transport phenomena.

ObjectivesIn this study, experiments and CFD (Computational Fluid Dynamics) simulations were conducted to investigate lead ion (Pb2+) adsorption in bentonite.MethodExperiments were carried out in a fixed bed column at 30°C, pH = 4.0 and average particle diameter of 0.127 mm. The influence of the flow rate on the breakthrough curves was examined with constant inlet concentration equal to 0.88 meq L-1. The CFD technique was used for the simulation of flow patterns and ion concentration profiles inside the fixed bed column during the adsorption process. A 2D axisymmetric model based on Navier-Stokes and diffusion-convection equations was used for simulating the fluid phase.ResultsExperimental data obtained for different inlet flow rates and Pb2+ concentrations were used for validating the model.ConclusionThe CFD simulations predicted the experimental behavior of the fixed bed adsorption very well in all conditions under study.