A Critical Analysis of Molten Salt Reactor (MSR) Safety Systems

A criticality analysis of Molten Salt Reactor (MSR) safety systems is carried out in this research. These systems are design to work in the event of an accident scenario, where a solid freeze plug (frozen fuel salt) melts, and the fuel salts volume drains into a number of storage tanks of non-critical geometry. For the purpose of this research, MONK Version 9A Monte Carlo Program by ANSWERS Software Service was used to carry out the criticality analysis for the drain tanks using the design geometry and specifications of the Molten Salt Research Experiment (MSRE) at the Oak Ridge National Laboratory (ORNL), Tennessee-USA. We assumed the composition of the fluoride salt mixture in the fuel drain tank to be: 42.16wt% LiF, 35.79wt% BeF, 21wt% ZrF4, 1.02wt% UF4, and 0.02wt% PuF3. The safety margin for subcriticality was determined.