CFD modelling of alumina feeding

Abstract

The dissolution and distribution of alumina in molten cryolite bath is a complex process, involving heat and mass transfer, phase transition and dynamics for a particle population with variable size and properties. Although single particle models can describe essential features of the process, they necessarily fail to capture features involving the interaction between particles (i.e. collisions and adhesion) and detailed coupling to the flow field, for which computational fluid dynamics (CFD) is needed. Several strategies and assumptions have been proposed in the literature, focusing on separate phenomena of relevance. Coupled models considering the full history of alumina particles have however not yet been developed. In the current work we investigate and review recent developments in coupled CFD particulate flow, aiming for general guidelines for implementation and use, with applications to both the gas-solid flow between the feeder and bath surface, and from the bath surface to dissolved alumina.