Towards model based re-design of the copper electro-winning process

High purity copper, suitable for electrical applications, can only be obtained by electrowinning. One aspect of this process is its self-induced natural convection through density variations of the electrolyte at both anode and cathode. The eventual goal is to highlight convective effects as main copper-transport mechanisms between the copper-winning electrodes. In order to do this, first the full dynamic complexity of the process needs to be understood. Thus an OpenFoam® based 3D model of the process has been created. This finite-volume multiphysics approach, solves the laminar momentum and copper-ion species conservation equations, as well as local copper-ion conversion kinetics. It uses a Boussinesq approximation to simulate the species-momentum coupling, namely natural draft forces induced by variations of the spatial copper concentration within the fluid. The model shows good agreement with benchmark-cases of real-life electrochemical cells, found in literature. Now the software can be applied to investigate how different forced convection conditions affect the speed of the entire copper-raffination process.