Performance of Thorium Uranium Nitride (Th, U233)N Fuel for 500 MWth GFR Long-Life Without Refuelling use FIITB-CHI Code

Performance of Thorium Uranium Nitride Fuel for 500 MWth GFR Long-Life Without Refueling use FI-ITB-CHI code has been done. Gas Cooled Fast Reactor use fast neutron spectrum, and belong to one of fast breeder reactor type. Thorium is three up to four times more abundant than uranium and is widely distributed in nature can be obtained in many countries. Natural thorium does not contain any fissile material and is made up of the fertile Th- 232 isotope only. Thorium fuel and fuel cycles are particularly relevant to countries having large thorium like Indonesia. The calculation use FI-ITB-CHI Code which has been verified by SLAROM code. The core calculation use R-Z geometry dimensional. The multi group diffusion calculation is carried out every year to get neutron flux distribution and power distribution. Then burn up calculation is carried out for each spatial mesh. The reflector radial-axial width is 50 cm. Parametric survey with various percentage of plutonium show the critical condition reach when 11% percentage of Pu and 60% fuel volume fraction. When the fuel volume fraction is increase, the reactor can be operated longer. The optimum value of heterogeneous core configuration when use 8% percentage of plutonium for F1, 10% for F2 and 14% for F3. The reactor can be operated almost 25 years without refueling.