Unit 1 of Balakovo nuclear power plant was connected to the grid on 27 December after scheduled repairs loaded with six Remix (regenerated mixture) fuel assemblies.
Remix fuel is an innovative Russian development for light-water thermal reactors. It is made from a mixture of reprocessed uranium and plutonium, which is formed during the reprocessing of used nuclear fuel, with the addition of enriched uranium. Compared with uranium-plutonium fuel for fast reactors (MNUP and mixed oxide), Remix has a lower plutonium content.
Balakovo 1 was closed for a regular maintenance and refuelling outage in November and was restarted five days ahead of schedule. The first batch of Remix fuel was loaded into the VVER-1000 unit on 21 December. Each of the Remix fuel assemblies of the standard TVS-2M design is fully equipped with fuel elements comprising a uranium-plutonium fuel (312 fuel elements in total).
During the outage, two dozen measures were taken to modernise equipment. Key operations include replacing the overheating part of the separator-superheater and replacing the generator rotors. “We carried out non-destructive testing of metal and welded joints of the main equipment of the power unit, including eddy current testing of heat exchange tubes of steam generators,” noted Aleksey Portnov, head of the Balakovo NPP repair management department.
Photo: First REMIX fuel assemblies loaded at Balakovo (Credit: Rosenergoatom)