The BN-800 sodium-cooled fast reactor at unit 4 of Russia’s Beloyarsk NPP has registered a year of reliable and safe operation using an almost full load of uranium-plutonium mixed oxide (MOX) fuel. Russia says this proves the readiness of the closed nuclear fuel cycle technology for implementation on an industrial scale. Beloyarsk 4 is the world's first nuclear power unit to use MOX for an entire year at almost full load. The MOX fuel assemblies (FAs) were produced at the Mining & Chemical Combine (MCC) in Zheleznogorsk, (Krasnoyarsk Territory). Unlike the enriched uranium FAs traditionally used in NPPs, the raw materials for the MOX fuel pellets includes plutonium oxide obtained during the processing of used fuel from conventional VVER reactors alongside depleted uranium oxide, obtained by defluorination of depleted uranium hexafluoride (tails from enrichment production).

The first serial MOX-FAs were loaded into the BN-800 core in January 2020. The first complete refuelling of the BN-800 with MOX fuel took place in January 2021, and then, over the next two refuellings, all fuel assemblies were gradually replaced with innovative MOX assemblies.

“MOX fuel is called the fuel of the future, because the implementation of a closed nuclear fuel cycle on an industrial scale will allow us to increase the fuel base of Russia’s nuclear power industry tenfold and reduce the formation of radioactive waste,” said Beloyarsk NPP Director Ivan Sidorov. “Our next step on the path to a new two-component nuclear power industry, in which fast and thermal neutron reactors will work together, exchanging fuel, is the construction of a power unit with the prototype of the BN-1200M serial reactor. This will make it possible to fully realise all the environmental and economic advantages of fast neutron reactor technology.”

Rosatom Director General, Alexei Likhachev in 2022 confirmed Russia's decision to build a BN-1200 sodium-cooled fast neutron reactor at unit 5 of the Beloyarsk NPP. Rosatom plans to obtain a licence for the construction for the BN-1200 in 2027. It will be the world’s largest fast reactor breaking the record already held by Russia for the BN-800. Construction of Beloyarsk 5 is scheduled for 2035. Public discussions and a positive environmental review are planned for 2025, according to Valery Shamansky, Deputy Chief Engineer for Safety & Reliability at Beloyarsk NPP. All design work should be completed in 2025, and construction will begin at the end of 2026-2027, he noted.

Image courtesy of Rosatom

Date: Wednesday, 08 November 2023
Original article: neimagazine.com/news/newsmox-use-at-russias-bn-800-reactor-confirms-reliability-of-the-technology-11278025