Neutron balance in two-component nuclear energy system
28th Symposium of AER on VVER Reactor Physics and Reactor Safety (2018, Olomouc, Czechia)
Spent fuel disposal and actinide transmutation
According to IAEA PRIS data most part of nuclear reactors under operation in the world are thermal reactors which consume U-235 in once-through fuel cycle. Such approach results in ineffective resource utilization and dramatic SNF volume growth. However, sustainable nuclear energy system (NES) should provide NFC closing for all hazardous radionuclides to minimize its life-time within NES and to make risk to be proportional to NES capacity, rather than total energy produced. These two basic principles require enough amount of neutrons for both energy generation and hazardous radionuclides transition to fission products. Therefore, taking into account politic, economic and technological risks and uncertainties, these issues can be solved in terms of two-component NES consisting of both thermal and fast reactors 1. In this work two methods to estimate neutron balance in NES are discussed. The fist method is based on the analysis of nuclear transformation chain due to radioactive decays and neutron induced reactions. The second one is the most complete one and relies on reaction rates comparison. Neutron balance estimation approach is demonstrated for two-component NES case study.
1. P.N. Alekseev, V.G. Asmolov, A.Yu. Gagarinskii et al. On a Nuclear Power Strategy of Russia to 2050. Atomic Energy, Vol. 111, No. 4, February, 2012 (Russian Original Vol. 111, No. 4, October, 2011)