Article

30 Years of experience in operating the BN600 sodium-cooled fast reactor

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Abstract

Experience in operating the BN-600 sodium-cooled fast reactor during its nominal service life as well as its service life extension period, an additional 15 years, is described. Information is presented on the performance indicators which were achieved and deviations from the normal operating regime which occurred when the reactor was first started up. The degree to which they affect the safety and technical-economic performance of the facility is evaluated. It is concluded on the basis of an analysis of the BN-600 operating experience that sodium-cooled fast reactors have now been mastered commercially and that their prospects for further development are good.

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...  Proven technologies and experience acquired in the design, commissioning and operation of BN-600 and BN-800 reactors should have broad use in the BN-1200 design to the greatest extent possible [18,19];  Testing and validation of improvements in the reactor safety, economic competitiveness and effectiveness of fuel management incorporating innovative technologies through the appropriate RD&D activities using existing and newly developed research facilities;  Optimization of the infrastructure requirements can be achieved through the selection of the appropriate value of the BN-1200 electrical power rating 18 and may involve unification of requirements for the NPP siting and unification of the electric generators and electric components used for the plant connection to the grid;  Transportation of the NPP components to the construction site by railroad. ...
...  Proven technologies and experience acquired in the design, commissioning and operation of BN-600 and BN-800 reactors should have broad use in the BN-1200 design to the greatest extent possible [18,19];  Testing and validation of improvements in the reactor safety, economic competitiveness and effectiveness of fuel management incorporating innovative technologies through the appropriate RD&D activities using existing and newly developed research facilities;  Optimization of the infrastructure requirements can be achieved through the selection of the appropriate value of the BN-1200 electrical power rating 18 and may involve unification of requirements for the NPP siting and unification of the electric generators and electric components used for the plant connection to the grid;  Transportation of the NPP components to the construction site by railroad. ...
... [20]. 18 Installed electrical power rating of BN-1200 was defined as equal to the electrical power rating of the advanced Russian water cooled reactors (AES-2006 or VVER-TOI). Based on the optimization studies performed in the Russian Federation for both sodium cooled fast reactors and water cooled reactors, the concept of 1200 MW(e) monobloc was adopted for the BN-1200 power plant. ...
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... В расчетных ячейках БР встречаются ячейки с наличием внешнего стального чехла и центральной ячейки с гомогенно представленными в ней теплоносителем и какии миилибо конструкциями (концевиками твэлов в реакторах типа БН [10,11] или техх нологическими трубами, например, как на рис. 2). ...
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Such satisfactory behavior has been confirmed not only for the beginning-of-life core state, but also for the equilibrium closed fuel cycle.
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New aspects of the development of a future nuclear power system based on the advanced technologies of a closed nuclear fuel cycle with fast-neutron reactors are discussed on the basis of an analysis of systems problems pertaining to present-day nuclear power. The systems requirements ensuring adequate fuel for nuclear power with any installed capacity and maximum use of natural uranium and thorium brought into the fuel cycle are formulated. Sodium-cooled fast reactors, which thus far possess the highest level of technological readiness for commercialization, are given a special role in the formation of a new technological platform for large-scale nuclear power of the 21st century.
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The data are presented on the operation experience of the BN-600 reactor with the sodium coolant in the primary and secondary circuits. High reliability of the equipment and sodium circuit systems, operating during 23 years, is shown. Violations of the reactor normal operation were effectively fixed and localized by the NPP safety systems. The unique experience of service and maintenance of the sodium equipment is obtained.
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In the paper are presented the main results of the BN-600 power unit operation during the last 16 years. Operation of the reactor core, main equipment, fuel charging and recharging systems, steam generators, sodium and steam-water circuits and electric equipment is described. Disturbances of normal operation and introduced improvements and modernization are described. It is shown that the BN-600 power unit by its technical and economical performances is in the number of 50% of the best NPP in the world.
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The various types of reactor systems which OKBM designed for different purposes over the 60 years of its existence are reviewed: commercial uranium-graphite and heavy-water reactors, reactors and steam-generating systems for naval and for civilian (icebreakers) ships, fast reactors, low-and medium-capacity reactor systems for regional power generation, and high-temperature gas-cooled reactors. The results of work performed by OKBM on the development of the cores of propulsion reactors and alternative fuel for VVR-1000 reactors are also presented.
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Data on the experience in operating the BN-600 reactor with sodium coolant in the first and second loops are presented. It is shown that the equipment and the systems in the sodium loops, which have operated for more than 23 years, are highly realiable. The average installed capacity utilization factor for this period reached about 74%. The losses due to rupture of the heat-transfer pipes in the steam-generator modules and the sodium leaks from the loops were about 0.3%. Disruptions of normal operation are detected reliably and contained by the safety systems present in the unit. Unique experience in performing maintenance and repair work on the sodium equipment has been gained on the BN-600 reactor.
Assessment of the operating efficiency of a power-generating unit with a BN-600 fast-neutron reactor at the Beloyarskaya nuclear power plant over 25 years of operation
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  • V B A A Vasiliev
  • O V Rogov
  • M R Mishin
  • Farakshin
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  • P P Govorov
  • A V Kuznetsov
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  • R P Baklushin
  • Y I Zagorelko
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  • M V Bakanov
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  • B A Vasiliev
  • VI Kostin
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  • O M Saraev
  • N N Oshkanov
  • V V Vylomov
  • OM Saraev
Operating experience and direction of development of BN-600 reactor core
  • B A Vasiliev
  • V A Rogov
  • O V Mishin
  • M R Farakshin