Abstract: Based on Computational Fluid Dynamics (CFD), a stirring-process simulation model of solid-liquid two-phase flow in the 25 m³ vertical reactor of copper anode mud leaching is established by using Euler-Euler multiphase model, multi-reference flame(MRF) model and standard k-ε turbulence model and the numerical simulation results of stirring power at different rotational speeds are further compared with those by the empirical formula. Meanwhile, the stirring speed, the blade installation angle, the blade distance and the damping baffle height are selected as the factors to evaluate the solid volume section concentration of vertical reactor. The orthogonal design method is applied to optimize the stirring conditions. The results show that the mathematical model is fit well with the empirical Nagata formula and it can be applied well in stirring simulation. The optimal combination is determined as follows: the stirring speed of 100 r/min, the blade installation angle of 45°, the blade distance of 1.615 m and the baffle height of 2 m. Under these conditions, the solid volume section concentration of the reactor is increased by 13% while compared with the actual production conditions.