Physical aspects for involvement of thermonuclear reactors into nuclear power systems

The paper analyzes a possibility to involve hybrid thermonuclear reactors into the existing nuclear power systems. The possibility is related with production of non-traditional nuclear fuel in thorium blanket of hybrid thermonuclear reactors on D-T plasma. Non-traditional peculiarity of such a fuel consists in significant amounts of some non-traditional isotopes, namely 231 Pa and 232 U, together with traditional uranium isotope 233 U in the fuel. High-energy (14.1 MeV) thermonuclear neutrons can provide accumulation of significant 231 Pa and 232 U quantities through threshold (n,2n) and (n,3n) reactions. The promising features of the non-traditional fuel composition for nuclear power thermal reactors, basic component of the existing world-wide nuclear power industry, are defined by the following factors. As is known, 233 U is able to provide more economical neutron balance in thermal reactors than 235 U and reactor-grade plutonium. The better neutron balance can result in higher values of the fuel breeding ratio and, as a consequence, in relaxation of the thermal reactors fuel self-sustainability problem. Isotopes 231 Pa and 232 U, being fertile and moderate fissionable nuclides, are able to stabilize time-dependent evolution of the thermal reactors power, prolong the thermal reactors lifetime through higher values of the fuel burn-up. Isotope 232 U, being intense α-emitter, is able to prevent any attempts for unauthorized usage of 233 U in nuclear explosive devices, i.e. 232 U can strengthen regime of nuclear non-proliferation. Thus, the hybrid thermonuclear reactors on D-T plasma with thorium blanket can be involved into nuclear power systems for generation of non-traditional, very promising fuel compositions for traditional nuclear power reactors.