Numerical Simulation of Oxide Particle Melting in a 6 kA Rare Earth Electrolyzer

The dissolution and diffusion behavior of lanthanum oxide in molten salt was investigated. The results indicated that when the feeding duration of lanthanum oxide was controlled at approximately 60 seconds, dissolution was nearly complete. Hence, a 60 second feeding duration is considered optimal. When the feeding position is located within the region corresponding to the anode slit, the concentration of lanthanum oxide is not uniformly distributed in the molten salt, which may lead to uneven anode consumption and adversely affect the electrolysis process. The analysis of the motion of lanthanum oxide particles reveals that a vortex in the molten salt was formed near the anode gap, resulting in a higher concentration of lanthanum oxide here than at this location compared to other positions, which in turn intensified anode consumption. Multiple experiments have demonstrated that the four-sided symmetric feeding method facilitates adequate movement of lanthanum oxide within the electrolysis zone, thereby promoting efficient electrolysis. These findings provide valuable insights for optimizing the feeding configuration in electrolyzer.