Numerical Simulation Of Impurities Trajectory In Rare Earth Electrolytic Cell

As the necessary key strategic resources of the emerging industry development, therare earth are widely used in electronic, aviation, environmental protection, new energyvehicles, wind turbines, especially for clean energy production. In recent years thedevelopment of domestic rare earth metals industry has become more and more faster, thetechnology of producing rare earth metals by molten salt electrolysis method has beendeveloped quickly. Currently, the3kA rare earth fluoride-oxide cell is widely used.Because of its simple structure, mature process technology and suitable for massproduction, has been get the favor of the industry. In recent years, by means of experimentand numerical simulation, the structure of3kA rare earth electrolytic cell and electrolysisprocess was optimized, the efficiency of electrolysis and the purity of rare earth metal havebeen greatly improved. But the plugged electrolytic cell have some unsolved problems,such as in the process of electrolysis, some suspended carbon particles will be generated inthe electrolytic cell, the carbon particles will cause the increase of the voltage drop inelectrolytic cell, affect the conductivity of the liquor and shorten the service life ofelectrolyzer, etc.This topic is mainly for carbon particles which generated in the electrolytic cellduring the electrolysis process, by the FLUENT simulation software, using the Eulermethod and the Lagrangian method to deal with the fluid and the trajectory of carbonparticles respectively, simulate the movement of the carbon particles in different particlesize. Gas plays a very important role in electrolytic process, it can prompt the molten saltflowing, it also promotes the movement of carbon particles directly. By the simulation indifferent conditions, the impurity can be wiped out directional in the actual productionprocess, and the production efficiency also can be improved in a relative degree. Thespecific work and results are as follows:(1) On the basis of the previous numerical simulation, using the optimal model of3kA electrolytic cell, the flow field distribution was simulated by Euler method, then themovement situation of different size particles were studied by the Lagrange method. (2) Comparing the movement situations of different size particles, found that thebigger particle size is, the greater range of movement.(3) Chang the electrolytic cell structure, such as the electrode insertion depth,simulate the movement of the particles, found that the deeper insertion depth is, the smallerimpact to particles, and the smaller distance of the particle deviate from anode, but whenthe electrolytic insertion depth is too deep, which is bad for electrolysis process.(4) Chang the spacing of electrolyzer cell cathode and anode, to get movementsituations of different size particles, found that the spacing of cathode and anode has littleeffect on the movement of carbon particle. When the anode diameter is same, the biggerthe size of the particles is, the greater distance of the particle deviate from the anode innerface.(5) Chang the current intensity of electrolysis, found that the distance range ofparticle movement away from the anode inner surface is not very big, but when the currentintensity is larger, the distance of particle movement is big relatively. The larger particlesize is, the greater distance away from the anode inner surface on the liquid surface.