A CFD-kinetic model for the flotation rate constant, Part II: Model validation

Abstract A Computational Fluid Dynamics (CFD) model was validated against published experimental data for the prediction of the flotation rate constant. An Eulerian–Eulerian framework was applied for modelling the multiphase flow inside a standard laboratory scale Rushton turbine flotation tank. The dispersed k–e turbulence model simulated the turbulent effects inside the tank, while the collision, attachment and stability efficiencies were calculated using the local values of hydrodynamic parameters. Volume-weighted average flotation rate constants were simulated for chalcopyrite and galena and compared against published experimental data for the same physical setup. The results showed that both qualitatively and quantitatively the developed CFD-kinetic model can predict the flotation rate constants with an acceptable level of accuracy. Moreover, the validations of rate constants for the flotation of chalcopyrite and galena under various contact angles, agitation rates and gas flow rates confirmed the predictive capability of this numerical approach for further flotation modelling.

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