[2F14-17] Molten Salt Reactor 1

[2F17] Feasibility Study of Integral Molten Chloride Salt Fast Reactor (II)

(4) Charasteristics of a small molten-salt fast reactor

*Koshi Mitachi¹, Yoichiro Shimazu¹ (1. Beyond Energy Research & Development Association)

Keywords:Molten Salt Reactor, Fast Reactor, Chloride Salt, NaCl-CaCl2, Trans Uranium Elements

Characteristics of a small molten salt fast reactor (MSFR) of 700MWth output was studied to utilize Trans Uranium Elements (TRU) and depleted uranium (U) effectively. The fuel salt used is a mixed salt of NaCl, CaCl₂, UCl₃ and TRUCl₃. This fuel salt is expected to have solidification temperature of about 530C and heavy-elements (TRU+U) solubility of about 30mol%. From the analysis of this study, the effective neutron multiplication factor of the MSFR could be more than 1.010, thus the feasibility of the reactor is cleared. The density coefficient of reactor reactivity is 20 times larger than the Doppler coefficient and the temperature coefficient of reactor reactivity becomes 1.1x10^-4 [1/K]. Reactor kinetic parameters (delayed neutron fractions and decay constants) could be evaluated based on the fractional compositions of fissile plutonium because the salt uranium is assumed to be u-238. The detailed data would be evaluation in the next fiscal year. These characteristics of MSFR were analyzed by SRAC2006 with SRACLIB-JDL40.