Kinetics of acid leaching of high Ca and Si manganese ores by experiments and CFD simulation in dual impeller stirred tank.

In this paper, 3D dual impeller stirring tank was used as a model to simulation combine with experiments to explore the acid leaching kinetics of high-calcium and -silicon manganese ores. The effects of stirring speed, temperature, and aeration rate on the spatial distribution of gas and liquid phases were investigated, and the influence of the gas phase on the flow state was further explored by using CFD (Computational Fluid Dynamics). Meanwhile, the effects of stirring speed, temperature, and aeration rate on the leaching rate of target element manganese were studied by experiments. According to simulations and experiments, stirring speed at 500 rpm perfectly. The aeration rate was 7 m/s, the suitable leaching temperature was 140 °C by experiments. These results also showed that the leaching of high-calcium and -silicon manganese ores follows the control of Interface chemical reaction.The apparent activation energy of the reaction was 43.4 kJ.mol⁻¹. [ABSTRACT FROM AUTHOR]