Investigation of Properties of KCl-MgCl2 Eutectic Salt for Heat Transfer and Thermal Storage Fluids in CSP Systems

Abstract

Eutectic molten salt MgCl2-KClis was considered as a high temperature heat transfer and thermal storage fluid, being able to work at temperatures up to 800 °C for concentrating solar thermal power. Thermophysical properties including vapor pressure, heat capacity, density, viscosity, and thermal conductivity, and the behavior of the corrosion of high temperature nickel-based alloys in the eutectic salt are investigated and reported in this work. Corrosion studies were carried out and measured at a temperature up to 800 °C over a time span of one week to one month. Low corrosion rate was observed for two types of high temperature nickel-based alloys under the environment that the salt is strictly processed to have a very low level of water and oxygen.