Revolutionizing LWR SMR reactors: exploring the potential of (Th-233U-235U)O2 fuel through a parametric study

• Published in: Energy sources. Part A, Recovery, utilization, and environmental effects Vol. 45; no. 4; pp. 10162 - 10175
• Main Authors: Lkouz, Mohamed, Kabach, Ouadie, Chetaine, Abdelouahed, Saidi, Abdelmajid, Bouassa, Taoufiq
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 02.10.2023
• Subjects: Criticality period; Neutronic characteristics; Reactivity coefficients; SMR; Thorium
• ISSN: 1556-7036; 1556-7230
• DOI: 10.1080/15567036.2023.2243859

Small modular reactors (SMRs) have garnered significant attention for their operational adaptability and ease of deployment. Thorium, with its well-documented advantages, shows promise as a viable fuel option for SMRs. However, the absence of intrinsic fissile components in thorium necessitates the exploration of different thorium-based fuel combinations. One such combination, (Th- 233 U)O 2 fuel, has limitations due to the presence of pure U-233. To overcome this challenge, a new fuel mixture, (Th- 233 U- 235 U)O 2 , was investigated for SMRs. This study examined the reactor physics characteristics of the (Th- 233 U- 235 U)O 2 fuel, including fuel burnup, neutron flux spectra, power distribution, the evolution of actinides, and reactivity coefficients. Results indicate that the (Th- 233 U- 235 U)O 2 fuel allows for a longer criticality period compared to UO 2 fuel, with up to a 14% improvement, while accumulating fewer plutonium and transuranic elements. Notably, it demonstrates significantly improved negative reactivity coefficients, particularly for moderator temperature, with an average improvement of 45% over (Th- 233 U)O 2 fuel. The conceptual (Th- 233 U- 235 U)O 2 fuel, therefore, exhibits promising neutronic properties, presenting possibilities for future studies. These findings contribute to the understanding and advancement of advanced fuel designs for SMRs.