Particle Tracking Simulation In The Fluid Of Rare Earth Electrolysis Cell

Rare earth is a new type of energy with practical significance and development prospects,and it is receiving more and more attention from the country and the region.Molten salt electrolysis has a simple production process and high economic efficiency,and is widely used in the preparation of rare earth elements.The metal ruthenium is prepared by molten salt electrolysis.However,it is found during the preparation process that the graphite particles in the pores of the anode are peeled off due to the chemical attack of the porous structure of graphite and oxygen at high temperature,and the carbon particles will enter the metal collector as the molten salt flows.Thereby the purity of the metal is lowered.In this paper,the 3kA Nd electrolytic cell is taken as the research object.The numerical simulation method is used to study the trajectory of particles in molten salt.The measures to reduce the movement of particles to the metal collector and the optimization scheme of the electrolytic cell are proposed to improve the purity of the metal.The details are as follows:In this paper,based on the phenomenon of carbon inclusion in molten salt and metal products,the physical model of flow field-particle coupling in the electrolysis cell was established by ANSYS software,and the trajectories of carbon particles in different particle sizes were studied.The numerical simulation combines the main forces of the carbon particles insoluble in the electrolyte in the flow field.It is found that the drag force and gravity are the main forces of the particles in the movement of the electrolytic cell,and the drag force varies with the particle size.Increase and increase,drag is the influencing factor to change the trajectory of particle movement;100?m particle size is the critical value that distinguishes whether the main force is gravity or drag.When the particle is less than 100?m,gravity is the main force,which is expressed as floating.When the particle is larger than 100 ?m,the drag force is the main force,and the larger the particle size,the more obvious the effect of the offset effect.For the anode easy to fall off part,change the anode inclination and chamfer to simulate.Through the change of the force,gas content and angular vortex of the particles during the movement,the trajectories of the particles before and after the anode structure are changed and analyzed.Through the combination of theory and numerical simulation,it is found that changing the anode inclination and increasing the anode chamfer the particle motion trajectory has a tendency to be far away from the inner surface of the anode,and the collision of the particles on the anode wall surface is relatively weakened,which is beneficial to slow down the phenomenon of anode carbon spalling and reduce the impurity content of the product.However,compared with the dip anode,when the chamfered anode is used,the anode gas content in the electrolyte is less,and the bubble discharge is more obviously promoted,which is obtained for the two parts where the graphite anode is most severely consumed.In summary,the anode bottom surface and the side joints pre-machined chamfered anode structure,a certain role in promoting the reduction of carbon impurities.