One of the important independent lines of work for JSC “Afrikantov OKBM” within the framework of designing and construction of facilities for the fleet, as well as for small-sized nuclear power plants, is the development and integrated scientific-technical validation of reactor cores. This line of work includes the development of design, the validation of mechanical strength, physical and thermal-technical characteristics of cores, nuclear safety and lifetime reliability, necessary calculations and experimental research in test facilities.
Equipment for handling nuclear fuel
These works are performed in cooperation with leading scientific institutes of the industry, first of all, with JSC "VNIINM,» NRC Kurchatov Institute, JSC “SSC RIAR”, as well as with the manufacturer—PJSC MSZ.
Since the commissioning of the first icebreaker reactor plant for the civil nuclear fleet, JSC “Afrikantov OKBM” has developed more than twenty core designs, brought to the stage of manufacturing and operation. The core element base improved from design to design, as well as post-reactor material science studies into spent fuel assemblies ensured continuous improvement of their lifetime and technical-and-economic characteristics.
Currently, serial cores for nuclear icebreakers ensure their intensive operation for 5–7 years.
The fuel of nuclear icebreaker cores under maneuverable operation conditions ensures an average burnout of unloaded fuel 1.4 times higher than that achieved in power reactors of VVER and PWR type.
At the same time, there is no yield of fission products to the coolant, which provides high radiation-ecological characteristics of the reactor unit.
Cores for operating and under-construction submarines have been developed and put into serial production, meeting existing and advanced requirements of the Navy in terms of reliability, safety, efficiency, fuel life, and service life, resistance to extreme external influences.
All scientific-technical bases have been created for developing a core, the life of which is designed for the entire service life of the ship on the basis of unique Russian materials and mastered industrial process. The use of such a core will ensure higher rates and efficiency of the ship operation, as well as to considerably reduce operating costs associated with nuclear fuel.
In 2008, the team of core developers from JSC “Afrikantov OKBM”, jointly with JSC "VNIINM,» NRC Kurchatov Institute, and PJSC MSZ, developed and approved a detailed design of the array core—that meets international nonproliferation requirements—for the world's first floating nuclear power plant based on the KLT-40S reactor plant (Akademik Lomonosov).
In 2011, two manufactured core packages for the FPU successfully passed acceptance testing and are scheduled for loading into the FPU reactors in 2019.
In 2014, on the basis of the improved array fuel assembly, a detailed core design for the under-construction multipurpose nuclear icebreaker of Project 22220 (Arktika) was developed and approved.
In 2016, two manufactured packages passed neutronic tests in the test facility of JSC “Afrikantov OKBM”, and in 2017, the packages will be prepared for loading into the multipurpose nuclear icebreaker reactors.
In the 1990s, on the basis of the accumulated scientific-technical potential, the team of core developers from JSC “Afrikantov OKBM”, together with PJSC MSZ, JSC "VNIINM”, and NRC Kurchatov Institute under the guidance of JSC “TVEL” created the advanced TVSA fuel assembly for the VVER-1000 reactors. It allowed the core to have geometrical stability at deep fuel burnout and meet the requirements for the advanced fuel cycles.
High technical-economic indicators and successful implementation of the TVSA fuel assembly developed by JSC “Afrikantov OKBM” together with enterprises of JSC “TVEL” for the Russian VVER-1000 reactor paved the way for developing a competitive design of the TVS-K fuel assembly for non-Russian PWR reactors.
In the course of pre-reactor and reactor testing of the TVSA fuel assembly, all its design characteristics were fully confirmed, which makes it possible to implement in nuclear power industry cost-effective fuel cycles with fuel life up to 6 years, a capacity factor of about 0.9, an average TVSA fuel assembly burnout of 60 MW day/kgU and up.
Positive operation results and the potential for further improvement of the fuel assembly make it possible to consider the TVSA fuel assembly as the preferred and competitive nuclear fuel in the domestic market and in Russia's conventional foreign markets.
This was confirmed by the TVSA fuel assembly winning the international bid for fuel supply for the Temelin NPP in the Czech Republic, implementation of the TVSA fuel assembly at four units of the Kalinin NPP, and virtually at all VVER-1000 units in Ukraine and Bulgaria.
Starting from 2003, JSC “Afrikantov OKBM” has conducted a considerable amount of R&D works under contracts with JSC “TVEL.” The obtained results allowed JSC “Afrikantov OKBM” to submit a proposal to PWR NPP operators for pilot operation of the TVS-K fuel assembly. This proposal aroused interest among a number of PWR NPP operators, including the Swedish VATTENFALL operator. Design documents were developed and the Company was licensed by Swedish regulatory authorities.
In May 2014, four TVS-K fuel assemblies of the LFA series were put into operation in the core of Unit 3 of the Ringhals NPP. Currently, four TVS-K fuel assemblies are located in the core of Unit 3 of the Ringhals NPP running the second cycle of operation.
On the basis of operation results, a decision can be made to supply the TVS-K fuel assemblies as a complete fuel package to the Ringhals NPP. The works on the Kolumb project using the TVS-K fuel assemblies are in progress.