New Uranium fuel will convert US research reactors from highly enriched to low enriched uranium

The US National Nuclear Security Administration (NNSA) has submitted to the US Nuclear Regulatory Commission a preliminary report on a new uranium fuel that will enable the conversion of six US research reactors from highly enriched uranium to low-enriched uranium.

The preliminary report on uranium-molybdenum (U-Mo) monolithic fuel contains data about the performance of the new fuel in a reactor and how it performs under a variety of conditions.

The international community is working to minimise amounts of HEU material, which could potentially be used for nuclear weapons. To that end, programmes are underway to convert research reactors to the use of LEU fuel, which does not present a proliferation risk. In some cases – including six high-performance research reactors in the USA – this can mean designing a new LEU fuel.

MITR is a light-water cooled and moderated, heavy-water reflected reactor which currently uses fuel enriched to 93%. Conversion of MITR will eliminate the transit of about 3 kilograms of HEU fuel per year, the NNSA said.