Sodium fast reactors as potential nuclear power plants in Nigeria’s quest for nuclear electricity

Abstract

The sodium fast reactor (SFR) was x-rayed in this work as a possible candidate for the Nigeria nuclear programme. In particular, the fuel economy and effects of reactivity were analyzed using the BN 600 as a prototype nuclear power plant (NPP). In a regime of closed fuel cycle, fast reactors are reputed for utilizing a large variety of fuels in sharp contrast to conventional reactors. Reaction rates and isotopic compositions of fuel elements were computed using the software “TIME 26”. The radial heat profile in the reactor core (RC) was aligned. Alignment was carried out by fuel enrichment in the peripheral part of the Active Zone (AZ), that is, Zone of Big Enrichment (ZBE). The corresponding fuel enrichment in the Zone of Small Enrichment (ZSE) was equally determined via a prompt enrichment factor (a) that ranges from 1.2 to 1.3. Parameters such as fuel campaign time and time interval between refueling were also determined. These parameters were limited to the maximum allowable burn-up value of the fuel which was set at 10%. With a Breeding Ratio (BR) of 1.2865, it is shown in this work that SFRs are able to reproduce their own fuel in contrast to thermal reactors. Further, the computed reactivity margin of 0.01283 is a key requirement for the plant internal safety. The implication for the Nigeria nuclear energy programme is discussed.

Keywords: Nuclear energy, Sodium Fast Reactor, BN 600, Nuclear fuel, Reactivity Effects