Russia has loaded what it claims are the world’s first fuel assemblies containing uranium-plutonium mixed oxide (MOX) fuel along with minor actinides into the Beloyarsk-4 BN-800 fast breeder reactor (FBR) near Yekaterinburg in central Russia.
Russia’s state nuclear operator Rosenergoatom said the fuel loading with the “innovative” assemblies is designed to confirm the possibility of industrial disposal of minor actinides.
Minor actinides are the most radiotoxic and long-lived components contained in used fuel. The possibility of eliminating them using fast neutron reactors will reduce the volume of radioactive waste from the entire infrastructure of the nuclear fuel cycle resulting from the operation of nuclear power plants, said Beloyarsk NPP director Ivan Sidorov.
Three experimental MOX assemblies containing the minor actinides americium-241 and neptunium-237 manufactured at Rosatom’s Mining & Chemical Combine (MCC) were loaded into the reactor core after approval by the regulator. State nuclear corporation Rosatom said the Federal Service for Ecological, Technological and Nuclear Supervision (Rostekhnadzor) had confirmed the safety of the assemblies.
In the BN-800 reactor, the assemblies will undergo experimental industrial operation during three cycles.
Beloyarsk-4 is an 820-MW FBR that began commercial operation in October 2016.
An FBR is designed to generate more fissile material than it consumes, allowing a significant increase in the amount of energy obtained from natural, depleted and recycled uranium.
The technology also enables plutonium and other actinides to be used and recycled, considerably reducing the amount of long-lived radioactive waste.
MOX fuel is manufactured from plutonium recovered from used reactor fuel, mixed with depleted uranium. It provides a means of using surplus weapons-grade plutonium for civilian energy generation. This eliminates the need for the storage of surplus plutonium, which needs to be secured against the risk of theft for use in nuclear weapons.
