Brest reactor and plant-site nuclear fuel cycle

Abstract

The fundamental design of BREST-OD-300 and BREST-1200 reactors is presented. It is shown that it is necessary to develop nuclear energy complexes based on the BREST nuclear system. The stages, the status of scientific research and development work over the entire nuclear power complex, and the results of an expert analysis of the BREST-OD-300 design are presented. Nuclear Power Complex.To meet the requirements imposed on large-scale nuclear power, the questions of a closed nuclear fuel cycle and fuel regeneration become fundamental, since the duration of the extra-reactor part of the cycle must be as short as possible.The residence time of fuel in the BN-800 fast sodium reactor is 1.4 years. In water-chemical fuel recovery at a centralized plant, the duration of the part of the fuel cycle outside the reactor is ~7 yr, i.e., there will be five times more fuel outside than inside the reactor. In addition, it will be possible to put six times fewer fast reactors into operation using the plutonium from the irradiated fuel of thermal reactors. The number of fast reactors operating on excess plutonium from fast reactors will also decrease by a factor determined by the ratio T in /(T in + T out ), where T in is the fuel run in the reactor and T out is the duration of the extra-reactor part of the fuel cycle, as if the excess breeding (BR − 1) was less by the same factor. Then, plutonium breeding in fast reactors becomes pointless.It follows that a closed nuclear fuel cycle for fast reactors must be on-site and fuel recovery must permit working with high-level fuel. This is also supported by the shipment of fresh and irradiated uranium-plutonium fuel to a centralized plant. Shipping fuel from one BREST-1200 reactor to a single plant (based on experience VVÉR-440) will require 10 railroad cars per year, and correspondingly 100 reactors will require 1000 cars (approximately 6 cars per day: three in and three out). In so doing, 8000 containers with high-level nuclear fuel (50-100 kg plutonium per container) will be used, which will require accident measures, radiation safety measures, and adherence to a nonproliferation regime, all of which are difficult to ensure at the present time.When long-lived actinides are burned in a reactor, only fission products will be present in the repository for radioactive wastes. After a holding time of 150-200, years the fission products can be buried at the uranium mining site without destroying the natural level of radioactivity and without long-distance shipments of high-level materials.Thus, a nuclear power complex must consist of a nuclear power plant, a nuclear fuel cycle on the plant site, and a waste repository on the plant site.Design of the BREST-1200 Reactor System. The BREST-1200 reactor system is a two-loop steam-generating power-generating unit, which contains a reactor with steam generators, pumps, equipment for reloading fuel assemblies, a safety and control rod system, a concrete shaft with a heat shield, a steam-turbine unit, systems for removing heat during

Thermal‐hydraulic analysis of wire‐wrapped rod bundle in lead‐based fast reactor with non‐uniform heat flux

“…As one type of the advanced fast reactor selected in the Generation IV Forum, the lead‐cooled fast reactor has the advantages of better neutron economy and higher boiling temperature, making the reactor safer and more compact 1 . There are some conceptual lead‐based reactors including BREST in Russia, 2 MYRRHA 3 and ALFRED 4 in Europe, SSTAR in America, 5 and CLEAR in China 6 . The fuel assembly is typically fixed by wrapped wires and arranged in a hexagonal duct for liquid metal fast reactors, which is remarkable compared to the grid spacers in most fuel assemblies 7,8 .…”

Lead-Cooled Fast Reactor Annular UN Fuel Design and Development of Performance Analysis Program

“…With the rapid development of the fast reactor technology, nitride fuel applied in lead-cooled fast reactors has attracted much attention, and nitride fuel is considered as one of the advanced fast reactor fuels (Yun et al, 2021;Glazov et al, 2007). Uranium nitride, as the main form of nitride nuclear fuel, is superior to conventional oxide fuels (MOX, UO 2 ) in multiple ways (see Table 1): it possesses higher heavy metal density as compared to oxide fuels, increasing the conversion ratio (CR); it has better thermal conductivity; the thermal conductivity increases as the temperature increases, which provides the fuel with better performance under transient conditions; and the fissile inventory ratio of UN is 10% higher than that of MOX fuel (Bo et al, 2013).…”

Heterogeneous Description of Fuel Assemblies for Correct Estimation of Control Rods Efficiency in BR-1200

“…The development of the reactor design is one of the directions for the implementation of the PROPYV project. The key requirement of the concept is exception of the most severe nuclear accidents mainly due to the properties and qualities of inherent natural safety in the neutron balance in the BR [1].…”