Nuclear Fuel Cycle with Minimized Waste

Abstract

A uranium-based nuclear fuel and fuel cycle are proposed for energy production. The fuel composition is chosen so that during reactor operation the amount of each transuranic component remains unchanged since the production rate and nuclear reaction rate are balanced. In such a ‘balanced’ fuel only uranium-238 content has a tendency to decrease and, to be kept constant, must be sustained by continuous supply. The major fissionable component of the fuel is plutonium is chosen. This makes it possible to abandon the use of uranium-235, whose reserves are quickly exhausted. The spent nuclear fuel of such a reactor should be reprocessed and used again after separation of fission products and adding depleted uranium. This feature simplifies maintaining the closed nuclear fuel cycle and provides its periodicity. In the fuel balance calculations, nine isotopes of uranium, neptunium, plutonium and americium are used. This number of elements is not complete, but is quite sufficient for calculations which are used for conceptual analysis. For more detailed consideration, this set may be substantially expanded. The variation of the fuel composition depending on the reactor size is not too big. The model accounts for fission, neutron capture and decays. Using MCNPX numerical Monte-Carlo code, the neutron calculations are performed for the reactor of industrial nuclear power plant size with MOX fuel and for a small reactor with metallic fuel. The calculation results indicate that it is possible to achieve criticality of the reactor in both cases and that production and consuming rates are balanced for the transuranic fuel components. In this way, it can be assumed that transuranic elements will constantly return to such a reactor, and only fission products will be sent to storage. This will significantly reduce the radioactivity of spent nuclear fuel. It is important that the storage time for the fission products is much less than for the spent nuclear fuel, just about 300 years.

Stellarator–mirror fusion–fission hybrid – a fast route to clean and safe nuclear energy

“…2012; Ternovykha et al. 2017; Moiseenko & Chernitskiy 2019). In cyclic reprocessing, after the burning sequence, fuel is unloaded from the reactor, fission products are removed, the corresponding amount of depleted uranium is added and finally new fuel is made from this mixture.…”

“…The project Integral Fast Reactor (Chang 1989) is of special interest, in particular because of its closing for safety reasons (see https://en.wikipedia.org/wiki/ Integral_fast_reactor). Some different approaches with multiple-recycle fuel cycles for fast reactors, which could provide radically higher aggregate combustion percentages, should be mentioned here (Orlov et al 2005;Moiseenko et al 2012;Ternovykha et al 2017;Moiseenko & Chernitskiy 2019). In cyclic reprocessing, after the burning sequence, fuel is unloaded from the reactor, fission products are removed, the corresponding amount of depleted uranium is added and finally new fuel is made from this mixture.…”