Russian fuel company TVEL plans to reach an agreement with the nuclear utility Rosenergoatom to irradiate reactor testing of accident-tolerant fuel (ATF) elements in a VVER-1000 reactor in the near future, TVEL Vice-President for Scientific and Technical Activities Alexander Ugryumov said on 27 September. He did not specify which version of the tolerant fuel is expected to be tested. Earlier TVEL listed four types of ATF being developed by Russian scientists including new fuel rod claddings and new fuel matrices. One option is the application of a heat-resistant coating based on chromium for fuel rod claddings to reduce the amount of hydrogen that could be generated in the event of a severe accident. This is the most advanced version which is now undergoing reactor tests at the Research Institute of Atomic Reactors (NIIAR) in Dimitrovgrad.
A second development is the use of the 42HNM alloy with mechanical properties that allow the thickness of cladding to be reduced. The third development involves changes to the fuel matrix, using uranium-molybdenum uranium dioxide fuel to increase the density of the fuel matrix and so increase the uranium capacity of the fuel assembly. TVEL is also working on the use of composite materials as shell materials, including silicon carbide, but some aspects of this remain problematic.
"Everything will depend on the first stage of reactor tests (at NIIAR’s MIR reactor), and the results obtained. We will then decide which options will be loaded for trial operation into one of the NPP units," Ugryumov said. This could be in 2020. He added that the Novosibirsk Chemical Concentrates Plant (NCCP – part of TVEL) is working on the ATF project and is producing pilot assemblies for irradiation at the MIR reactor.
TVEL is also developing new innovative fuel for research reactors at NCCP. TVEL president Natalia Nikipelova told a seminar at NCCP on 25 September that “the fuel market for research reactors is no less a priority for Fuel Company TVEL than the fuel market for power reactors” and that TVEL was “implementing a large-scale programme of cooperation with foreign partners in this field, offering our fuel for the specific needs of our customers”. Konstantin Vergazov, senior vice-president for scientific and technical activities, technology and quality at TVEL, said NCCP is the main producer of fuel for research reactors in Russia. "In recent years, NCCP has not only completely modernised the production of fuel for the Russian design, but has also mastered a whole range of new types of fuel for Russian and Western needs. NCCP chief designer Anatoly Enin told the seminar that plant produces more than 60 modifications of fuel assemblies for reactors operated in Russia and abroad. Ugryumov noted that fuel-based on uranium-molybdenum alloys was also being developed for research reactors.
On 21 September, TVEL and the European Organisation for Nuclear Research (CERN) signed an agreement on R&D within the framework of the Future Circular Collider (FCC) project. The document is in addition to the existing framework agreement on industrial partnership between the parties, which is aimed at cooperation in the field of superconducting materials. As part of the agreement TVEL’s Chepetsk Mechanical Plant (ChMZ) in Glazov, Republic of Udmurtia, is to manufacture several different superconducting niobium-tin wire constructions for CERN.
The FCC, which is to be built in Switzerland to replace the Large Hadron Collider, will require the delivery of a significant amount of superconducting wire. This can only be produced by joint international efforts by those states that have the technology. Development of wire for the FCC project is also underway in the USA, Europe, South Korea, Japan and China. In Russia, the development of niobium-tin superconductors involves the AA Bochvar Research Institute of Inorganic Materials (VNIINM) as well as ChMZ. Applied superconductivity is one of the strategic directions in the development of non-nuclear technologies at TVEL.
