The solid-liquid separation characteristics of pure LiCl-KCl eutectic salt using different types of crucibles

Uranium deposits were recovered at the solid cathode of an electrorefining system, and deposited uranium dendrite normally contains about 30-40 wt% LiCl-KCl eutectic salts. Therefore, a separation of the eutectic salts from deposited uranium is essential for reusing these salts and uranium. A process such as distillation was employed for cathode processing due to the advantages of a minimal generation of secondary waste, a compact unit process, and simple and low-cost equipment. However, the realization of a wide evaporation area or high distillation temperature is limited by various factors such as the material or structure of a distiller. Also, the electrical energy flow from outside has a lot of consumption to maintain the high temperature. Hence, in this study, solid-liquid separation experiments are proposed to increase the throughput of the salt removal process by the separation of the liquid salt prior to the distillation of the LiCl-KCl eutectic salt. The solid-liquid separation of salt was carried out in a vertical type distiller. The behavior of the solid-liquid separation of pure eutectic salt was investigated as a function of temperature, pressure, sieve size, and crucible shape. From the experimental results using pure eutectic salts, the amount of salt separation was achieved at more than 94 wt%. The rate of solid-liquid separation of salt using 600 deg C is higher than that of 500 deg C under the same condition. The influence of a vacuum for solid-liquid separation can be disregarded, and the separation rate of a 100 mesh was higher than that of a 150 mesh. In addition, the rate of separation for salts using a porous crucible is higher than that in a non-porous crucible. (author)