Study On The Movement Trajectory Of Unmelted Neodymium Oxide Particles In Rare Earth Electrolysis

Rare earth elements are a general term for lanthanide elements and elements with similar chemical properties.In the process of national development,it's widely used in many fields,including new energy,aerospace,missiles and nuclear submarines.Because the 3kA rare earth electrolysis cell has the advantages of convenient operation,mature technology and simple structure,it is still widely used in the rare earth industry.With the development of computer technology,we have a certain understanding of rare earth electrolysis cell through numerical simulation.But many problems remain to be solved.For example,in the process of cerium oxide particle blanking,the particle size of the raw material particles and the input point of the raw material have an influence on the electrolysis process.If not well solved,the particles will form nodules at the bottom of the cell and the life of the cell will be shortened.In this topic,the blanking process of neodymium oxide particle is taken as the main line in the blanking.By means of numerical simulation,the molten electrolyte in the electrolyzer and the particle movement in the blanking process are simulated to the particle movement under different particle sizes.Through the simulation of different working conditions,it can be helpful for the addition of particles and subsequent removal of nodules in the actual production process.The specific work is follows:(1)The model of 3kA rare earth electrolyzer is adopted.The Euler method is used to simulate the electrolyte flow field distribution,and the Lagrange method is used to simulate the particle motion.Through simulation,the larger the particle size,the farther the particle moves,but the trajectory is similar.At the same time,it is most suitable to have the particles in the middle of the two electrodes.(2)Study on the effect of changes in electrode insertion depth on particle motion.Through the simulation of the electrode insertion depth of 150 mm,185mm,220 mm,255mm,280 mm,it is find that the greater the electrode insertion depth,the larger the critical particle size of the particle.The farther the distance of motion,but the trajectory is similar.Through simulation of electrode insertion depth in different working conditions show that 220 mm is the optimal electrode insertion depth and the critical particle size is 0.7mm.It is also most beneficial for controlling the formation of nodulation.(3)Study on the effect of changes in pole spacing on particle motion.Through the simulation of five working conditions with pole spacing of 25 mm,50mm,75 mm,100mm and 115 mm,it is find that the larger the pole spacing,the smaller the critical particle size of the particle.The distance of particle motion does not change much,but the trajectory is similar.Through the simulation of the pole spacing of different working conditions show that the pole spacing of 75 mm is the best working condition and the critical particle size is 1.9mm.It is also most beneficial to control the formation of nodulation.(4)There are still many measures to inhibit the formation of nodular substances in the electrolytic cell.Such as,adding LiF in the electrolytic cell regularly,controlling the blanking speed,developing new electrolytic cell,etc.It is very helpful for extending the life of the electrolytic cell.