Use of Neptunium-containing Fuel in Lead-cooled Fast Reactor

Abstract

The paper analyzes a principal capability to transmute neptunium, the main component of transuranium radiowastes (TRW), in lead-cooled fast BREST-type reactor. High-energy neutron spectrum of the BREST-type fast reactor makes it possible either to eliminate neptunium in fission reactions or convert neptunium to plutonium with large fraction of ²³⁸Pu in radiative neutron capture reactions. According to the IAEA regulatory documents, plutonium containing above 80% ²³⁸Pu is regarded as an unsuitable material for manufacturing of nuclear explosive devices. Besides, good neutron-multiplying properties of ²³⁸Pu and ²³⁹Pu can prolong substantially the reactor core lifetime. Thus, introduction of neptunium into fresh fuel composition can eliminate the largest TRW fraction, strengthen regime of nuclear non-proliferation, produce some additional amount of thermal energy and prolong the reactor core lifetime.