China Nonferrous Metallurgy

In the process of copper electrorefining， the flow behavior and mass transfer characteristics of the electrolyte have a significant impact on electrolytic efficiency， product quality， and energy consumption. In industrial electrolytic cells， the electrode size is much larger than the spacing between electrodes， forming a special narrow space between the anode and cathode plates， making the electrolyte flow and mass transfer characteristics more complex and variable. This study establishes a two-dimensional finite element numerical model of a industrial-scale electrolytic cell and conducts an in-depth analysis of the electrolyte flow velocity distribution， copper ion concentration distribution， and transport characteristics within the narrow space between the anode and cathode plates， leading to the following main conclusions. The electrolyte flow velocity between the plates is uneven， slower in the upper region and faster in the lower region， with multiple vortex areas formed； near the surfaces of the anode and cathode， the horizontal velocity is almost 0， the vertical velocity fluctuates in the range of 0. 3-15 mm/s， the horizontal velocity along the centerline fluctuates in the range of 0-22 mm/s， and the vertical velocity fluctuates in the range of 0-9 mm/s. The vortices between the plates have a significant effect on the copper ion concentration distribution. Near the cathode surface， copper ion concentration fluctuates in the range of 440-620 mol/m3； near the anode surface， it fluctuates in the range of 530-740 mol/m3； along the centerline， it fluctuates in the range of 500-630 mol/m3， with the concentration fluctuations corresponding to the vortex areas. Copper ion transport is primarily driven by convection， and the lateral flow between vortices achieves direct transport of copper ions from the anode to the cathode. While transferring copper ions from the anode to the cathode， the vortices also carry suspended impurities formed near the anode to the cathode surface， resulting in higher impurity content on the lower region of the cathode surface compared to the upper region.