Title: Sustainable criticality analysis of PCMSR fuel using thorium as sustainable fuel and low enriched uranium as starting fuel
Authors: Andang Widi Harto
Addresses: Engineering Physics Department, Faculty of Engineering, Universitas Gadjah Mada, Yogyakarta, Indonesia
Abstract: PCMSR is designed to utilise thorium. Thorium will be converted to fissile 233U. LEU will be used as initial fissile fuel to avoid the use of Pu or HEU. The criticality can be maintained by balancing the production and consumption of 233U, and the depletion of 235U. The composition of initial fuel is 6.3% mole of UF4, 23.7% mole of 232ThF4 and 70% mole of 7LiF. The initial uranium enrichment is 19% mole of 235U. The fuel composition and criticality will be analysed by solving the simultaneous nuclide balanced equations coupled with multi-group neutron diffusion equation. The calculations are performed for specific power of 9, 18, 27 and 36 MWth/(ton HM). The results show that the PCMSR can maintain its criticality for long-term operation (i.e. 100 years). The criticality depression is recognised at initial operation time and becomes more prominent as the specific power increases.
Keywords: PCMSR; passive compact molten salt reactors; thorium fuel; LEU starting fuel; sustainable criticality analysis; low enriched uranium; nuclear energy; nuclear power; long-term operations; simultaneous nuclide balanced equations; multi-group neutron diffusion equations.
DOI: 10.1504/IJNEST.2015.074098
International Journal of Nuclear Energy Science and Technology, 2015 Vol.9 No.3, pp.224 - 237
Received: 29 Apr 2015
Accepted: 11 Oct 2015
Published online: 08 Jan 2016 *