Study on an Optimal Condition of Closed Chamber Distillation Equipment for Regeneration of LiCl-KCl Eutectic Salt Containing Rare Earth Phosphates

In closed chamber distillation equipment, the distillation characteristics of LiCl-KCl eutectic salt containing rare earth phosphates were investigated to establish an operating condition to maximize the operating efficiency of the equipment. To understand the behaviors of LiCl-KCl eutectic salt in the distillation chamber, changes in the pressure in the distillation equipment were observed with a change in the temperature gradients between the vaporization chamber and condensation chamber, and the temperature distributions in the chamber were modeled using computational fluid dynamics software (ANSYS CFX). Based on these results, a model of the salt behavior in the chamber was established, and the most effective operating condition for over 99 wt% of salt recovery was determined. Many distillation experiments of LiCl-KCl eutectic salt containing rare earth phosphates were performed at the condition, and it was confirmed that the salt recovery efficiency (>99 wt%) could be consistently achieved at the condition.