Orlov M.A.
Innovation and Technology Center of the Proryv Project, Moscow, Russia
The article proposes simplified tools for maintaining the equilibrium reactivity mode (reactivity margin in a microcampaign below the effective delayed neutron fraction) throughout the entire service life of a fast reactor started with uranium nitride fuel and then operated in a closed nuclear fuel cycle. The neutronic analysis in view of partial refueling has shown that the basic "inherent safety" requirement can be met using just one or two modifications of the fuel load properties during a transition from a startup with a U fuel to a fuel with an equilibrium isotopic U-Pu composition. It is proposed to increase the burnup along the transition. The preferred option for adjusting the neutronic characteristics of the core is changing the gap between the fuel and the cladding in liquid metal sublayer fuel rods. A conservative option of modifying the fuel tablet density in gas gap fuel rods, and an advanced option where the low-absorption 15N isotope concentration in the fuel is changed are also considered. Optimization strategies for minor actinide utilization intended to decrease reactivity margin in the transition mode and to enable denaturation of Pu generated within the startup fuel load are suggested.
The research is relevant since fast reactors are expected to become more competitive (e.g., through power generation cost reduction) in the nearest future as they are started up with enriched uranium instead of U-Pu (this premise is being verified).
1. Naumov V.V., Orlov V.V., Smirnov V.S. Toplivnyy balans yadernoy energetiki s bystrymi reaktorami bez uranovogo blanketa [Fuel balance of nuclear power with fast reactors without uranium blanket]. Atomnaya energiya - Atomic Energy, 1994, vol. 76, no. 4, pp. 349–350.
2. Adamov E.O., Gabaraev B.A., Ganev I.Kh., Dzhalavyan A.V., Lopatkin A.V., Murav'ev E.V., Orlov V.V. Vklad NIKIET v formirovanie strategii razvitiya yadernoy energetiki Rossii [The contribution of NIKIET to the development of the strategy for the development of Russia's nuclear power industry]. Atomnaya energiya - Atomic Energy, 2007, vol. 103, no. 1, pp. 5–15.
3. Smirnov V.S., Umanskiy A.A. Start bystrykh reaktorov na obogashchennom urane – vozmozhnost' krupnomasshtabnogo razvitiya yadernoy energetiki bez vysokogo bridinga plutoniya [The launch of fast reactors on enriched uranium is an opportunity for large-scale development of nuclear power without high-grade plutonium breeding]. Byulleten' po atomnoy energii - Bulletin on Atomic Energy, 2008, no. 8, pp. 26–31.
4. Murav'ev E.V. Toplivoobespechenie yadernoy energetiki s vvodom bystrykh reaktorov [Fuel supply of nuclear power with the introduction of fast reactors]. Izvestiya Akademii nauk. Energetika - Proceedings of the Academy of Sciences. Power engineering, 2014, no. 5, pp. 75–86.
5. Baschwitz A., Mathonniere G., Gabriel S., Eleouet T. Deployable nuclear fleet based on available quantities of uranium and reactor types — the case of fast reactors started up with enriched uranium. Proceedings of Global 2015. Paris, France, 2015, pp. 31–40.
6. Orlov M. Complex discussion of inhereht safety fast reactors start-up with enriched uraniun concept (strategical, economical aspects, problems of neutron physics etc.). R&D program proposal. Proc. Int. Conf. on Fast Reactors and Related Fuel Cycles: Next Generation Nuclear Systems for Sustainable Development. Yekaterinburg, 2017, pp. 454.
7. Volkov I.A., Simonenko V.A., Makeeva I.R., Dyrda N.D., Belonogov M.N., Trapeznikov M.A. Ispol'zovanie obogashchennogo urana v bystrom reaktore so svintsovym teplonositelem [The use of enriched uranium in a fast reactor with a lead coolant]. Atomnaya energiya - Atomic Energy, 2016, vol. 121, no. 1, pp. 20–25.
8. Orlov V.V., Lemekhov V.V., Smirnov V.S., Umanskiy A.A. Sposob ekspluatatsii yadernogo reaktora na bystrykh neytronakh s nitridnym toplivom i zhidkometallicheskim teplonositelem [The method of operation of a fast neutron nuclear reactor with nitride fuel and a liquid metal coolant]. Patent RF, no. 2501100, 2013.
9. Chernobrovkin Y., Shevchenko A., Rodina E., Dedul A., Lopatkin A., Leonov V. Fundamental approaches to high-power fast reactors core development. Proc. Int. Conf. on Fast Reactors and Related Fuel Cycles: Next Generation Nuclear Systems for Sustainable Development. Yekaterinburg, 2017, pp. 19.
10. Lyon W.F., Baker R.B., Legget R.D. Performance analysis of a mixed nitride fuel system for an advanced liquid metal reactor. Proc. "LMR: a decade of LMR progress and promise". Washington, D.C., USA, 1990.
11. Bauer A.A., Brown J.B., Fromm E.O., Storhok V.W. Mixed Nitride Fuel Irradiation Performance. Proc. of ANS Conf. on Fast Reactor Fuel Element Technology, Materials Science and Technology Division. Hinsdale, Illinois, 1971, pp. 785-818.
12. Delage F., Carmack J., Lee C.B., Mizuno T., Pelletier M., Somers J. Status of advanced fuel candidates for Sodium Fast Reactor within the Generation IV International Forum. Journal of Nuclear Materials, 2013, vol. 441, pp. 515–519.
13. Grachev A.F., Zabud'ko L.M., Glushenkov A.E., Ivanov Yu.A., Kireev G.A., Skupov M.V., Gil'mutdinov I.F., Grin' P.I., Zvir E.A., Kryukov F.N., Nikitin O.N. Issledovaniya smeshannogo nitridnogo uran-plutonievogo topliva v ramkakh proekta "Proryv" [Studies of mixed nitride uranium-plutonium fuel in the framework of the project "Proryv"]. Atomnaya energiya - Atomic Energy, 2017, vol. 122, no. 3, pp. 156-167.
14. Mark J. Carson. Explosive Properties of Reactor-Grade Plutonium. Science&Global Security, 1993, vol. 4, pp. 111–128.
15. Avrorin E.N., Chebeskov A.N. Bystrye reaktory i problema yadernogo nerasprostraneniya [Rapid reactors and the problem of nuclear non-proliferation]. Izvestiya vuzov. Yadernaya energetika - Proseedings of Universities. Nuclear Power Engineering, 2014, no. 1, pp. 64–76.
