Lead—Bismuth Fast Reactor

SVBR-75/100 (Russian Federation) Svinetc-Vismuth Bystriy Reactor (Lead-Bismuth Fast Reactor)... 

Conservative approach was used in the design of SVBR-75/100 (lead-bismuth fast reactor of 75-100 MW equivalent electric power, depending on steam parameters), which provides for the retention of operation parameters of the primary and secondary circuits at the levels that have been already mastered in practice, for the use of qualified fuel and structural materials and proven technical solutions for the equipment components and reactor installation scheme. This approach assures that technological approaches implemented in other reactor installations, first of all, the propulsion reactors of nuclear submarines, have been to the maximum possible extent inherited by the SVBR-75/100 design. Adhering to this approach reduces the terms, scope and costs of necessary R D and investment risk, and secures high reliability and safety of the reactor installation. 

In Russia, two initiatives are currently being pursued. One of these is known as the SVBR (Svintsovo-Vismutovyi Bystryi Reaktor or Lead—Bismuth Fast Reactor ) (Zrodnikov et al., 2009). The SVBR-100 is generally considered a foUow-on technology to the prior submarine propulsion technology and is a small reactor cooled by LBE. The second major initiative, known as the BREST Bystry Reaktor so Svintsovym Teplonositelem or Fast Reactor with Lead Coolant ) (Dragunov et al., 2012), is a medium-sized reactor cooled by pure lead and detailed further in this chapter as one of the reference LFR reactor systems in the Generalion IV program (GIF-LFR-pSSC, 2014). 

SVBR Svintsovo-vismutovyi bystryi reactor (or in English lead—bismuth fast reactor )... 

Studies of lead-bismuth and lead-cooled fast reactors are being carried out in the Russian Federation (RF) organizations Institute of Physics and Power Engineering (IPPE) and EDO... 

Preliminary studies on lead-bismuth and lead cooled reactors and ADS (accelerator driven systems) have been initiated in France, Japan, the United States of America, Italy, and other countries. Considerable experience has been gained in the Russian Fedaration in the course of development and operation of reactors cooled with lead-bismuth eutectic, in particular, propulsion reactors. Studies on lead cooled fast reactors are also under way in this country. 

Studies of Jead-bismuth fast reactors are being carried out in the Russian Federation organizations IPPE and GIDROPRESS, in which a great deal of experience has been accumulated in the course of the development and operation of submarine reactors cooled with lead-bismuth eutectic. However, bismuth is expensive and the resources are limited. It is possible that its use must be confined to special applications, such as small reactors or to a limited number of fast reactors. For this reason lead cooling is also being studied. 

The lead-cooled fast reactor uses either lead or lead-bismuth eutectic in the primary coolant loop. This gives similar advantages as with the SFR in terms of operational safety. Several of these reactor designs were built and operated on Russian submarines. 

Small Lead- bismuth Cooled Reactor Japan XXI Fast reactor 50/132 30 (U-Pu) N 10.5-18.2 Natural circulation Pb-Bi 335/505 Indirect Rankine ... 

Despite the fact that the proposed reactor technology is backed by a long design and operating experience of the lead-bismuth cooled reactors for nuclear submarines and the fast spectrum reactors with sodium coolant for NPPs it is still innovative for civil nuclear power. Therefore, additional validation and testing, as well as licensing would be required. 

Small lead-bismuth cooled fast reactors SVBR-75/100 discussed in this paper are based on actual experience in the development and operation of lead-bismuth cooled reactors for nuclear submarines [1]. In fifteen-twenty years from now it will be possible to deploy SVBR-75/100 in both industrialized and developing countries. These reactors make it possible to resolve a contradiction between economic characteristics and safety requirements that is peculiar to reactors of traditional type. Due to their improved technical and economical characteristics and higher safety level, fast reactors with lead-bismuth coolant could be considered as one of the possible candidates for step-by-step replacement of thermal reactors [2]. 

Of the six liquid metal cooled SMRs, three are sodium cooled fast reactors (KALIMER, BMN-170 and MDP), and 3 are lead-bismuth cooled fast reactors (RBEC-M, PEACER-300/550, and Medium Scale Lead-bismuth Cooled Reactor). All designs implement indirect thermodynamic cycles. All sodium cooled SMRs incorporate intermediate heat transport systems (secondary sodium circuits to transport heat to a steam turbine circuit and to prevent the possibility of a contact of water with the primary sodium). All lead-bismuth cooled SMRs have no intermediate heat transport system. All designs use steam turbine power circuit. 

High conversion or breeding are generally inherent to all reactors with the fast neutron spectrum however, they could be improved by the use of dense metallic (KALIMER, BMN-170, MDP, PEACER) or nitride (RBEC-M, BMN-170, Medium Scale Lead-bismuth Cooled Reactor) fuel for the nitride fuel, an option of nitrogen enrichment by is being considered (RBEC-M, Medium Scale Lead-bismuth Cooled Reactor). 

The concept of PEACER [XXIV-1], a fast lead-bismuth cooled reactor for electricity generation and waste transmutation, was proposed in 1998. The present research includes innovative reactor design development for the transmutation of spent nuclear fuel, the development of three-dimensional (3D) virtual reality technology and the demonstration of Pb-Bi coolant technology. 

With a purpose of probing a commercially feasible fast reactor system, a feasibility study on commercialized fast reactor cycle systems (FS) was initiated in 1999 (Aizawa, 2001). In the FS, survey studies were made to identify the most promising concept among various systems such as sodium-cooled fast reactors, gas-cooled fast reactors, heavy metal-cooled fast reactors (lead-cooled fast reactors and lead-bismuth cooled fast reactors), and water-cooled fast reactors with various fuels types such as oxide, nitride, and metal fuels. The FS concluded to select an advanced loop-type SFR with mixed oxide fuel named Japan sodium-cooled fast reactor (JSFR Kotake et al., 2005). 

Lead bismuth eutectic Lead-cooled fast reactor Liquid metal embrittlement Oxide dispersion-strengthened (alloy)... 

Further away in time are possibilities of using fast reactors, though, at least for some decades, not as breeders. The Soviet navy has been using such reactors, using a lead/bismuth eutectic mixture as coolant, for some decades in some of their high performance submarines and it is understood that work is now going on to see whether this design could be made suitable for small commercial power production... 

In the earlier phases of breeder reactor development, especially in the 1950s and 1960s, high pressure gases, such as helium,C02 or superheated steam were studied. Between 1960 and 1970, H2 0-steam cooled and D2 0-steam cooled fast reactor concepts were studied in the USA and the former FRG. Helium cooled fast reactor concepts have been pursued as an alternative coolant concept in Europe and the USA. Some fuel development for a CO2 cooled fast breeder has been continued on a small scale in the UK. Lead-bismuth alloy as a coolant was studied in the former USSR for propulsion and land based reactors. 

Not only new innovative ideas as, for example, lead or lead-bismuth cooled fast reactors are being studied in Member States now, but almost all old ones mentioned above... 

Considerable experience has been gained in the Russian Federation with lead-bismuth (PbBi) eutectic alloy application as reactor coolant. Since Bi is sufficiently rare and expensive metal, and also it is a source of volatile a-active Vo, the proposal to use lead as a coolant in power fast reactors is now under consideration in several countries. Lead based alloys are currently being considered for hybrid systems (accelerator driven fast reactors) in which the coolant could double as the spallation source for driving the core. 

That is why this report is devoted to the comparative assessment of general characteristics of a standard fast reactor coolant (sodium) and innovative ones, such as lead and lead-bismuth alloy. 

V I. OUSANOV, D. V. PANKRATOV et al, Long-lived Radionuclids of Sodium, Lead-bismuth and Lead Coolants at Fast Reactors . Atomnaia Energia,V.87, 9,pp. 204-210, 1999(Rus). 

Long term residual activity of sodium, lead-bismuth and lead coolants of fast reactors have been studied and compared by V. Ousanov, D. Pankratov, et al. [7.4]. It was found, that specific a-activity of typical lead-bismuth coolant is determined by Bi-210m (half-life = 3.6 x 10 years) generated in reaction Bi-209 (n,y) Bi-210m. The long lived p-activity of Bi-208 (half-life = 3.65 XlO years) is produced in the reaction Bi-209 (n, 2n) Bi-208. 

COMPARATIVE ASSESSMENT OF THERMOPHYSICAL AND THERMOHYDRAULIC CHARACTERISTICS OF LEAD, LEAD-BISMUTH AND SODIUM COOLANTS FOR FAST REACTORS IAEA, VIENNA, 2002 IAEA-TECDOC-1289 ISBN 92-0-113602-1 ISSN 1011-4289... 

The need to exchange information on alternative fast reactor coolants was a major consideration in the recommendation by the Technical Working Group on Fast Reactors (TWGFRs) to collect, review and document the information on lead and lead-bismuth alloy coolants technology, thermohydraulics, physical and chemical properties, as well as to make an assessment and comparison with respective sodium characteristics. This report considering these issues has been prepared in response to the recommendation from TWGFR. 

The possibility and expediency of developing the NP based on unified small power reactor modules SVBR-75/100 with fast neutron reactors cooled by lead-bismuth eutectic coolant (LBC) is substantiated for the nearest decades in the paper. 

Analysis of the characteristics of liquid-metal coolants, such as sodium (Na), lead (Pb) and lead-bismuth eutectic (Pb-Bi), makes it possible to decide on the coolant for the new fast reactor considered as a basic component of large-scale nuclear power, which will be capable of taking over the greater part of the electricity generation increase and, possibly, of providing for other energy-intensive processes. 

The LFR is a fast-neutron spectrum reactor cooled by molten lead or a lead-bismuth eutectic liquid metal. It is designed for the efficient conversion of fertile uranium and the management of actinides in a closed fuel cycle. 

ZRODNIKOV, A.V., et al.. Lead-bismuth reactor technology conversion from NS reactors to power reactors and ways of increasing the investment attractiveness of nuclear power based on fast reactors, paper presented in the Conf Fifty years of nuclear power-the next fifty years, 27 June-2 July 2004, Moscow, Russian Federation. 

In the field of fast reactor design and operational data, the last reference document published by the IAEA was the 1996 Fast Reactor Database (IAEA-TECDOC-866). Since its publication, quite a lot has happened the construction of two new reactors has been laimched, and conceptual/design studies were initiated for various fast reactors, e.g. the Japanese JSFR-1500 and the Russian BN-1800 (both cooled by sodium), as well as for a wholly new line of LMFR concepts — modular reactors cooled by sodium and by lead-bismuth alloy, and prototype and demonstration conunercial size fast reactors cooled by lead. 

As indicated by Table 2 and several design descriptions given in the annexes, achieving a CR >1 appears feasible in the several concepts of small fast-spectrum reactors with lead and lead bismuth coolant, especially when dense nitride fuel is employed. Should it work out in practice, such reactors will not loose to larger-size LMFBRs in the efficiency of uranium ore... 

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