Inherently safe lead — bismuth — cooled reactors

Abstract

The strategic path toward the safest possible nuclear power plants is to switch to inherently safe nuclear reactors, capable of self-shielding, without interference by man, in any accident situations. Examples of such plants are modular medium and low-power plants based on fast reactors with a breeding ratio close to one. As a result, in such plants the operational reactivity margin is less than/~eff, negative temperature feedbacks are present, the void effect of reactivity is negative, and the colloant is a liquid metal whose aggregate state remains unchanged in the entire operating temperature range and at the temperatures reached during accidents. The physical properties of such reactors eliminate reactivity accidents with runaway on prompt neutrons and the chain reaction is self-quenched in any accident.Liquid-metal coolant, combined with the single-unit construction of the plant, implementing passive cooldown (when all other possibilities are precluded) through the reactor vessel to naturally circulating atmosphere air, will make it possible to avoid destructive overheating of the core. This concept is being implemented in the USA in the projects ALMAR (PRISM and others) and in Russia in lead-cooled reactors, which are being developed by the Scientific-Research and Design Institute of Energy and Fuels [1], and in designs with lead-bismuth coolant, which are being developed by the Institute of Physics and Power Engineering and the Special Design Office "Gidropress" [2]. Japan has also started the conceptual development of such lead-cooled plants.The transition to lead-bismuth liquid-metal coolant, which is inert with respect to water and air, makes the concept of an inherently safe fast reactor more complete than the ALMR concept, which is based on sodium as the coolant.Mastery of Lead-Bismuth Alloy as a Coolant. Russia was the first to use and has unique experience in assimilating and using this coolant in application to moving power plants. The scientific development was directed by the Institute of Physics and Power Engineering and the engineering development was directed by the Special Design Office "Gidropress" and the Special Design Office for Machines.Work on the application of the eutectic alloy lead-bismuth was started in this country at the initiative and under the leadership of A. I. Leipunskii in 1952. The fundamental problems arising in the development of a nuclear power plant with such a coolant, including the questions of heat transfer, hydrodynamics, coolant technology, corrosion, mass transfer, and many others, were solved. The required experimental base, equipped with unique test stands, was created. Commercial and prototype nuclear power plants, on which operation, repair, and refueling of the reactors were perfected and preliminary service-life tests of the equipment were performed, were constructed. The total service life of a nuclear power plant with lead-bismuth coolant was -80 reactor.years.During this work skilled teams of investigators, designers, and operating personnel, capable of ...

Idaho National Laboratory Lead or Lead-Bismuth Eutectic (LBE) Test Facility - R&D Requirements, Design Criteria, Design Concept, and Concept Guidance

“…18,19 A methodology for injection of gaseous mixtures of H 2 and H 2 O into the coolant flow to purify the Pb and Pb-Bi circuits of slag deposits. 20 The development of solid phase oxidizers to control the thermodynamic activity of Pb and Pb-Bi coolants. 20 The development of an absorption technique to extract dissolved impurities in liquid-metal coolants (e.g., Ga, Pb, Pb-Bi).…”

“…20 The development of solid phase oxidizers to control the thermodynamic activity of Pb and Pb-Bi coolants. 20 The development of an absorption technique to extract dissolved impurities in liquid-metal coolants (e.g., Ga, Pb, Pb-Bi). The technique is based on retention of dissolved and highly dispersed impurities in a liquid-metal by absorbent surfaces in a filter medium, through which the coolant is pumped.…”

Status of Research and Development of the Lead-Alloy-Cooled Fast Reactor

“…8, AUGUST 2003 the colder regions of the system. The Russians 6) have found that steels with relatively low concentrations of nickel (0.8%) and relatively high concentrations of silicon (1.3%) and vanadium (0.4%) seem resistant to corrosion when in contact with molten Pb-alloys at temperatures up to 600 • C. 5,79,80) Corrosion rates of steel by Pb-alloys have been reduced through the addition of oxidation inhibitors (e.g., zirconium, tungsten, and chromium) in the coolant 66,77,78) and surface coatings. Inhibitors require strict concentration control, as depletion of these minor additives adversely affects the corrosion rate.…”

An Assessment of Reactor Types for Thermochemical Hydrogen Production

“…Polonium-210 is very toxic and difficult to contain [7]. Nonetheless, the former Soviet Union developed and used PbBi-cooled reactors, and the PbBi-cooled approach has been proposed by several laboratories as an advanced power production reactor [17][18][19][20]. Bismuth possesses a higher melt temperature than the PbBi eutectic and offers no significant advantages over PbBi-cooled reactors.…”