| At present,small rare earth electrolytic cells are still the mainstream equipment for many enterprises to prepare rare earth metals,but the equipment has problems such as low output,low electrolytic efficiency and scattered distribution.Many large enterprises have transformed to develop large current rare earth electrolytic cells to solve the problems and meet the demand for high-quality rare earth metals.However,during the electrolysis process,there will be phenomena such as rapid consumption of graphite anodes,short effective working time and large residual waste,and the consumption of anodes will affect the distribution of physical fields in the cell,reducing the electrolysis efficiency of the cell.This paper takes the 15 k A rare earth electrolytic cell as the research object,simulates the anode consumption process,and observes the change law of the three-dimensional electric field and temperature field in the cell with the anode consumption.On this basis,the anode structure parameters are improved to achieve the purpose of more durable graphite anodes and reduced residual waste,and to obtain the best parameters of the optimized anode structure.The detailed research contents are as follows:(1)A transient simulation model of the consumption process of graphite anode in a 15 k A rare earth electrolytic cell was established,and the change law of the shape and size of the graphite anode with the electrolysis time during the consumption process of the graphite anode was simulated,and the consumption law of the graphite anode was obtained by analyzing the data.At the same time,three anode structure optimization schemes are proposed for "α angle","β angle" and "trapezoid" optimization.(2)Use finite element software to model the three-dimensional electric field of the electrolysis cell,simulate the change of the three-dimensional electric field distribution in the cell during an electrolysis cycle,and compare the electric field distribution at the beginning of anode consumption and the time of replacement,and analyze the uneven distribution of the electric field caused by anode consumption.Impact.Then,the three-dimensional electric field after the anode structure optimization is simulated,and the electric field distribution,cell voltage and current density change with the optimized angle and distance are obtained,the optimal parameters of the optimized anode structure are obtained,and the rationality of anode structure optimization is explored.(3)The electro-thermal coupling model of the electrolysis cell was also established to simulate the change of the three-dimensional temperature field in the cell in one electrolysis cycle,and compared the three-dimensional temperature field distribution in the cell at the beginning of anode consumption and the time of replacement.It was found that the maximum temperature in the cell increased with the increase of electrolysis time.decreased,and the range of the high temperature area was reduced.However,after the anode structure is optimized,the maximum temperature in the tank has recovered,and the area where the temperature distribution range fits the optimal temperature of the electrolysis is large,which can promote the efficient electrolysis reaction.Three kinds of anode structure optimization are analyzed to improve the effective use time of anode and reduce the waste of residual anode,and establish a simulation model of anode electrochemical transient consumption for the optimized electrolytic cell.It is found that the effective use time of the anode is greatly improved after the optimization of the anode structure.After the optimization of the graphite anode structure,the volume of the graphite anode increases,and the residual waste of the anode is reduced.Therefore,a single graphite anode is more resistant to consumption,and the effective use time of the anode can be extended by up to 43% before the optimization.%,the anode replacement frequency is reduced,and the reduction of the temperature in the tank due to frequent anode replacement is avoided. |
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