Passive safety characteristic at Innovative Molten Salt Reactor (IMSR)

The next generation of Nuclear Reactor Technology development is directed to increase of the aspects of safety, fuel utility, radioactive waste reduction, proliferation retention and economy. Innovative Molten Salt Reactor (IMSR) is a thermal breeder nuclear reactor that uses fluoride molten salt (7LiF-ThF4-UF4-MaFx). Using breeder reactor, the problem of natural nuclear fuel sustainability and radioactive waste can be solved. IMSR reactor system has inherent safe characteristics, i.e. negative temperature reactivity coefficient, and negative void reactivity coefficient. The passive safety features are passive shutdown systems, passive post shutdown cooling system and passive radioactive waste cooling system. In term of passive shutdown, the components failures act automatically as the shutdown mechanics. The IMSR passive shutdown systems are the fuel circulation system (fuel circulation pumps and fuel regulator valve) and primary coolant circulation system (primary coolant pumps). During shutdown, the primary coolant system will act as passive post shutdown heat removal system. (author)