Hydrodynamics of annular centrifugal contactors: A CFD analysis using a novel multiphase flow modelling approach

Annular Centrifugal Contactors (ACCs) are a promising process intensification technology for liquid–liquid extraction. Still, there is a limited understanding of the hydrodynamic conditions observed within ACCs and Computational Fluid Dynamics has the potential to shed light on this. However, the presence of a broad range of interfacial scales prevents the use of standard multiphase flow models. Therefore, a generalized multiphase modelling approach has been proposed, which allows for the simulation of multiscale multiphase flows. This approach has been applied to the simulation of a laboratory-scale ACC. It is demonstrated that the approach can provide information on the hydrodynamic behaviour of the system including hold-up, droplet size distribution and residence time; this, in turn, allows evaluation of the mass transfer performance. It is concluded that the modelling technique represents a valuable tool for gaining in-depth understanding of the hydrodynamics of ACCs, thus allowing for the prediction of their performance.