Funding Agency: DOE-NEUP, 2024-2027

Abstract (link to NEUP abstract)

PI:

Prof. L. Vergari (University of Illinois Urbana-Champaign)

Collaborators:

Prof. T. Kozlowski (University of Illinois Urbana-Champaign)
Dr. C. Tsai (Idaho National Lab)
Dr. K Dolan (Kairos Power)
Dr. T. Drzewiecki (Kairos Power)

This project aims to investigate and quantify the behavior of tritium in advanced nuclear reactors, with a particular focus on Fluoride-Salt-Cooled High-Temperature Reactors (FHRs) and High-Temperature Gas Reactors (HTGRs). Tritium, a radioactive hydrogen isotope, is produced at significantly higher rates in FHRs and HTGRs compared to traditional Light Water Reactors (LWRs). However, current data on tritium concentration in graphite does not reflect the specific conditions of these next-generation reactors. In addition, tritium gets trapped in graphite, impacting the neutron moderation and so the reactivity, potentially altering the progression of postulated events. Furthermore, since tritium-graphite interactions are temperature-dependent, the fraction of trapped tritium released during reactor transients involving temperature increases remains uncertain.

To address these gaps, the project will measure tritium content in graphite components, evaluate its impact on reactor physics, and quantify its release during temperature fluctuations. By conducting experimental studies with hydrogen isotopes as surrogates, the project will generate critical data on tritium adsorption, its influence on neutron moderation, and release kinetics during reactor transients. The findings will contribute to enhancing the safety and efficiency of next-generation reactors, supporting the Department of Energy’s mission to improve nuclear reactor performance and reliability.

ABC Lab Researchers: G S Rakib, Erdem Yelmenoglu