Experimental Design for Testing Materials Corrosion in Molten Fluoride Salt

摘要

One of the potential benefits of many of the GEN-IV concepts is that in addition to providing electricity, they also allow for thermo-chemical hydrogen separation from process heat. The interface between the reactor and the hydrogen production system will likely involve long heat transfer paths at elevated temperatures. A potential transport fluid for the heat exchange loop is a molten fluoride salt due to its large specific heat and thermal conductivity, high density at low pressures, resistance to radiolysis, and relative chemical inertness. These characteristics are conducive to minimizing the temperature drop in the intermediate heat transport loop and the required pumping power, thereby minimizing the delivered cost of the process heat. An immediate challenge for using molten fluoride salts is their corrosive nature at the desired high temperatures of use. Corrosion at high temperatures in fluoride salts is unlike high temperature corrosion in other environments in that the protective passive films that form on the materials surface are generally unstable.