2023 journal article

A thermal natural uranium breeder reactor for large and small applications with passive safeguard designs

Progress in Nuclear Energy.

By: R. Hayes n‚ÄČ & M. Sawyers n

UN Sustainable Development Goal Categories
Source: ORCID
Added: July 2, 2023

This research explored a novel reactor design capable of hyper-breeding, potentially greater than any design previously evaluated (fast or thermal). Reactor breeding estimates at power were predicted to exceed 1.55 (Hayes, 2006) using only natural uranium making it of substantial interest for obtaining a high burnup fuel cycle. It has also been shown capable of starting with only natural uranium (NU) fuel making it highly attractive from a non-proliferation or small modular reactor (SMR)/microreactor perspective. The breeding capability also allows for partial refuelling with depleted uranium (DU) with a new core burnup capability >3 GW yr (Hayes, 2007, 2008). Previous scoping calculations demonstrated great promise having only evaluated metallic, unclad slab fuel geometries without considerations for material performance after irradiation or the thermal hydraulics of such a system. This work reviews the technical basis for such a neutron economy where reactor physics considerations demonstrate how such a heterogenous configuration enables apparently drastic changes in reactor performance. These changes subsequently create the potential for application in SMR/microreactor technology such that high enriched low assay uranium (HALEU), and its associated inherent limitations, may not be necessary. In addition, novel non-proliferation technology is also considered which could further mitigate closed fuel cycle models for this reactor concept by providing passive monitoring capabilities such that the design incorporates multiple layers of safety and security. Overall, the technology here argues for a novel set of technologies making for passively non-proliferation safe nuclear reactors.