A sodium-cooled fast reactor is a fast neutron reactor cooled by liquid sodium. Important safety features of the system include a long thermal response time, a large margin to coolant boiling, a primary system that operates near atmospheric pressure, and intermediate sodium system between the radioactive sodium in the primary system and the water and steam in the power plant. 'r��N�i����si|��F�h)Ǟ�K�?��R%�'�j:��ʥPq��g���ص�ݷe]��~���!�H��Dsf��O [2] The high temperatures reached by the coolant (the Phénix reactor outlet temperature was 560 C) permit a higher thermodynamic efficiency than in water cooled reactors. There have been two main design approaches to sodium-cooled reactors. When nuclear fission was discovered in 1938, 235U existed at 0.7% in naturalUranium (decayed down from over 25% when Earth was formed). The surface alloying by the so-called GESA method enhances corrosion resistance of the structural material further, at least up to 870 K The SFR's fast spectrum also makes it possible to use available fissile and fertile materials (including depleted uranium) considerably more efficiently than thermal spectrum reactors with once-through fuel cycles. [3], A disadvantage of sodium is its chemical reactivity, which requires special precautions to prevent and suppress fires. Reactivated in 2010, then permanently closed. world’s first operational sodium-cooled reactor. IAEA NUCLEAR ENERGY SERIES PUBLICATIONS STRUCTURE OF THE IAEA NUCLEAR ENERGY SERIES Under the terms of Articles III.A and VIII.C of its Statute, the IAEA is authorized to foster the exchange of … 3 0 obj The US EBR-2, French Phénix and others used this approach, and it is used by India's Prototype Fast Breeder Reactor and China's CFR-600. for Fast Reactors Cooled By Sodium, Lead, and Lead-Bismuth Eutectic No. Let me explain how this came about. <> It was a liquid metal … Each reactor design is given a three-character designation consisting of: 1. 1 0 obj Sodium-23 is a very weak absorber of neutrons. þ  neutron poison (thermal neutron capture cross section greater than 3k barns) The SFR design benefits … Few lead-cooled reactors have been constructed, except for some Soviet nuclear submarine reactors in the 1970s, but a number of proposed new nuclear reactor designs are lead-cooled. As a fast reactor, the SFR appeals to the Gen IV requirements of greater fuel efficiency and the reduction in waste production. 4 0 obj %PDF-1.5 With innovations to reduce capital cost, such as making a modular design, removing a primary loop, integrating the pump and intermediate heat exchanger, or simply find better materials for construction, the SFR can be a viable technology for electricity generation.[11]. A consecutive generation number 3. %���� Air flowing past the outside of the tubes removed heat, cooling the liquid sodium inside. Design Study on Sodium-Cooled Fast Reactor Core Loaded with LLFP Transmutation Sub-Assemblies Naoyuki TAKAKI * and Tomoyasu MIZUNO JAPAN NUCLEAR CYCLE DEVELOPMENT INSTITUTE O-arai Engineering Center, 4002, Narita-cho, O-arai-machi, Higashi-Ibaraki-gun, Ibaraki, 311-1393 Japan ... V. Sodium-Cooled Core with LLFP Sub-Assemblies 1. <>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 612 792] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> The USS Seawolf submarine initially used a Na-cooled reactor that was replaced in 1959 by a PWR to standardize the fleet, because of superheater bypass problems causing mediocre performance and as a result of a sodium fire.The steam turbines had their blades replaced to use saturated rather than superheated steam.The reactor was housed in a containment vessel designed to contain a sodium fire. A letter for the reactor's designer ("W" for Westinghouse, "G" for General Electric, "C" for Combustion Engineering, and "B" for Bechtel) For example, a S9G reactor represents a submarine (S), ninth-generation (9), General Electric designed reactor (G). The concept is generally very similar to sodium-cooled fast reactor, and most liquid-metal reactors have used sodium instead of lead.Few lead-cooled reactors have been constructed, except for some Soviet nuclear submarine reactors in the 1970s, but a number of proposed new nuclear reactor designs are lead-cooled.. [10], The SFR is designed for management of high-level wastes and, in particular, management of plutonium and other actinides. In theory a liquid sodium, or liquid lead cooled reactor core could be very very small for it's power loading. Fuel-to-cladding chemical interaction (FCCI) has to be designed against. Reactor Database. ƒ  fissile For operational vessels in 1997, Bellona lists 109 Russian submarines (plus four naval surface ships) and 108 attack submarines (SSN) and 25 ballistic missile ones apart fro… SABRE4 (Dobson and O’Neill, 1992) is widely used in the UK; it is a 3-D sub-channel code designed to predict the thermal-hydraulics of a sodium fast reactor fuel assembly. Without isotopic enrichmentavailable (of uranium or hydrogen in water), only a handful of configurations couldsustain a chain reaction. Sodium features a reasonably low melting temperature, but also a low boiling point (1156 ... class submarines and its effectiveness up to 820 K has been confirmed by the EU ADS research. ThePowerReactorInnovativeSmallModule(PRISM) designedbyGEHitachiNuclearEnergyisasmall,mod- ular, sodium-cooled fast reactor. In these types of steam generators two phase length … containing more liquid sodium Control rods Reactor core Heat exchanger Sh Steam generator Turbine … Although the USS Seawolf have completed her sea trials, some major draw-backs in the sodium cooled project made it less attractive than the water cooled project, and the sodium-cooled reactor was deemed by Admiral Hickover as ex-pensive, complex, and difficult to repair. Will be followed by BN-1200M as a model for export. Rather, it was cooled by liquid (molten) sodium. [2], Another problem is sodium leaks, regarded by critic of fast reactors M.V. On November 30, 2019, CTV reported that the 3 Canadian provinces of New Brunswick, Ontario and Saskatchewan are planning an announcement about an interprovincial plan to cooperate on small sodium fast modular nuclear reactors from New Brunswick-based ARC Nuclear Canada. SLTHEN is a modified version of ENERGY, specifically developed for LMR (e.g., sodium fast reactor), providing improved computational efficiency and simplified energy equation mixing model ( Yang, 1997 ). Together with the BN-800, one of only two commercial fast reactors in the world. The fuel sub-assembly consists in a hexagonal duct wall wrapped around the fuel pins (Fig. Moreover, the high thermal conductivity of sodium effectively creates a reservoir of heat capacity which provides thermal inertia against overheating. �ē��!��E8X��tY%�־�Åu���. ~����؋�F�8���h�FZm�����i(�x��ή�T!O~ ֋�P��C�c�q�������+�9���V���pP�]���e����.O��8�%�ڏ��"�#tDD�z���#n�뱗 The Westinghouse Lead Fast Reactor (LFR) is a medium-sized, passively safe modular reactor being developed to reduce front-end capital cost and generate flexible and cost-competitive electricity. However, the end-of-core-life arrived and the boat was put in the hands of its builders in December 1958 to begin conversion to the water-cooled plant. When combined with the Soviets efforts for … Reference Core Specification The neutronic and … Suffered a terrorist attack during its construction. Sodium features a reasonably low melting temperature, but also a low boiling point (1156 K), which raises safety concerns regarding unprotected transients leading to a coolant heat-up. Several sodium-cooled fast reactors have been built, some still in operation, and others are in planning or under construction. Ramana as "pretty much impossible to prevent".[4]. The nuclear fuel cycle employs a full actinide recycle with two major options: One is an intermediate-size (150–600 MWe) sodium-cooled reactor with uranium-plutonium-minor-actinide-zirconium metal alloy fuel, supported by a fuel cycle based on pyrometallurgical reprocessing in facilities integrated with the reactor. Because of its compact core, Admiral Hyman G. Rickover, the father of the US nuclear navy, had a sodium-cooled reactor built for the second US nuclear submarine. New sodium-cooled reactors are under construction in Russia, China and India. To achieve greater efficacy and power density, the Navy built Seawolf with a liquid metal (sodium) cooled nuclear reactor. endobj In development. Despite sodium's low specific heat (as compared to water), this enables the absorption of significant heat in the liquid phase, even allowing for safety margins. Seawolf traveled over 71,000 miles on her sodium-cooled plant, and interestingly not one single reactor compartment entry was made during the roughly two year time span in which the SIR Mark B, later known as S2G plant was operated. The alloy that forms has a low eutectic melting temperature. However, the end-of-core-life arrived and the boat was put in the hands of its builders in December 1958 to begin conversion to the water-cooled plant. In addition, neutrons cause it to become radioactive; however, activated sodium has a half-life of only 15 hours. A primary water circuit transfers heat generated from nuclear fission in the fuel to a steam generator; this water is kept under pressure so it does not boil. №  primarily a naturally occurring radioactive material (NORM) Westinghouse is currently developing a Lead-cooled Fast Reactor (LFR) concept – a next-generation nuclear plant designed to compete even in the most challenging global energy markets. Nautilus sported the former, and Seawolf the sodium-cooled S2G Submarine Intermediate Reactor (SIR). The S1G reactor is a naval reactor used by the United States Navy to provide electricity generation and propulsion on warships.The S1G designation stands for: S = Submarine platform 1 = First generation core designed by the contractor; G = General Electric was the contracted designer; This nuclear reactor was constructed by General Electric as a prototype for the USS Seawolf submarine. Liquid metallic sodium may be used as the sole coolant, carrying heat from the core. A letter for the type of ship the reactor is intended for ("A" for aircraft carrier, "C" for cruiser, "D" for destroyer, and "S" for submarine) 2. Bill Gates' TerraPower is planning to build its own reactors named Natrium.[1]. The Soviets were pushing very very high speeds out of their submarines to help them run the various NATO ASW defences. More recent fast reactors under construction: – CEFR (China) 2008 25 MW e – PFBR (India) 2010 500 MW e – BN-800 (Russia) China has an ambitious vision to deploy 200 GWe of sodium-cooled fast breeder reactors by 2050 (12% of projected capacity). The S2G designation stands for: S = Submarine platform 2 = Second generation core designed by the contractor The French Rapsodie, British Prototype Fast Reactor and others used this approach. In once through type steam generators water enters as single phase liquid (sub cooled) gets evaporated and superheated and leaves as super heated steam. A sodium-cooled fast reactor is a fast neutron reactor cooled by liquid sodium. The Seawolf submarine reactor was unique because it was not a light-water cooled reactor like that installed in the Nautilus. The submarine’s operational life was cut short due to a reactor accident. 1 SODIUM TECHNOLOGY . The primary advantage of liquid metal coolants, such as liquid sodium, is that metal atoms are weak neutron moderators. SODIUM COOLED FAST REACTORS: 1. After the previous success applying SHARP to challenging SFR problems, the focus in FY19 and FY20 expanded to additional fast reactor applications including lead cooled fast reactors (LFR) and sodium cooled fast reactors (SFR). By comparison, the liquid temperature range of water (between ice and gas) is just 100K at normal, sea-level atmospheric pressure conditions. 100–210 ka ... Legend for superscript symbols At that time, in 1947, we did not know which one would work. The lead-cooled reactor design has been proposed as a generation IV reactor.Plans for … FCCI is eutectic melting between the fuel and the cladding; uranium, plutonium, and lanthanum (a fission product) inter-diffuse with the iron of the cladding. Sodium has only one stable isotope, sodium-23. Most of these were experimental plants, which are no longer operational. Workers additionally increased the maximum limit on the temperature of the primary loop’s liquid sodium to enable SRE to operate at a higher power level. endobj Each PRISM produces 311 MW of electricity. Another advantage of liquid sodium coolant is that sodium melts at 371K and boils / vaporizes at 1156K, a total temperature range of 785K between solid / frozen and gas / vapor states. 2 0 obj The PRISM core is lo- cated in a pool-type containment vessel and is fueled with metallic fuel. While actually a sub-actinide, it immediately precedes actinium (89) and follows a three-element gap of instability after, This is the heaviest nuclide with a half-life of at least four years before the ", https://www.reuters.com/article/us-usa-nuclearpower-terrapower/bill-gates-nuclear-venture-plans-reactor-to-complement-solar-wind-power-boom-idUSKBN25N2U8, "TerraPower Quietly Explores New Nuclear Reactor Strategy", "Neutronic Assessment of Transmutation Target Compositions in Heterogeneous Sodium Fast Reactor Geometries", https://www.ctvnews.ca/politics/three-premiers-plan-to-fight-climate-change-by-investing-in-small-nuclear-reactors-1.4709865, Idaho National Laboratory Sodium-cooled Fast Reactor Fact Sheet, Generation IV International Forum SFR website, "Meet the Man Who Could End Global Warming", Small sealed transportable autonomous (SSTAR), https://en.wikipedia.org/w/index.php?title=Sodium-cooled_fast_reactor&oldid=996274778, Short description is different from Wikidata, Creative Commons Attribution-ShareAlike License. (Bellona gives 247 subs with 456 reactors 1958-95.) totype to be installed on land, an operational reactor to be installed in the sub-marine, and a spare reactor [4]. Basic operation of naval ship or submarine Most naval nuclear reactors are of the pressurized water type, with the exception of a few attempts at using liquid sodium cooled reactors. NP-T-1.6 Guides INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA ISBN 978–92–0–131810–7 ISSN 1995–7807. The outlet temperature is approximately 510–550 degrees Celsius for both. The S2G reactor was a naval reactor used by the United States Navy to provide electricity generation and propulsion on warships, and the only liquid metal cooled reactor yet deployed by the US Navy. New sodium-cooled reactors are under construction in Russia, China and India. (1). stream A liquid metal cooled nuclear reactor, liquid metal fast reactor or LMFR is an advanced type of nuclear reactor where the primary coolant is a liquid metal.Liquid metal cooled reactors were first adapted for nuclear submarine use but have also been extensively studied for power generation applications.. Metal coolants remove heat more rapidly and allow much higher power density.This … Suspended for 15 years. <>>> Enrico Fermi and co. figured it out by 1942, and operated thefirst nuclear reactor, the Chicago Pile 1 (CP-1), using pieces of natural uranium metaldispersed carefully in a lattice of high-purity graphite blocks in a Chicago squash court. Magnesium oxide has been proposed as the inert matrix. endobj [12], Type of nuclear reactor cooled by molten sodium, Actinides and fission products by half-life, Plus radium (element 88). [3] The molten sodium, being electrically conductive, can also be pumped by electromagnetic pumps. When it does absorb a neutron it produces sodium-24, which has a half-life of 15 hours and decays to magnesium-24, a stable isotope. 2). Largest SFR ever built. x��Z[o�:~/���}s�D�(R�E�I�6mNP�8=���t��-������P�E�T�8�Ij���\��f��aU�35�٧O�úV�LOٯ�q����x�����5/T���� ��|�n�?\?,�=����㇀��_��H���"��b���^�_>~�5^�����������&)�$���5x1��NM��s�Z�. This was the case at the Monju Nuclear Power Plant in a 1995 accident. It also needs no pressure vessel, as the liquid metal is typicaly at atmospheric pressure. FCCI causes the cladding to reduce in strength and could eventually rupture. The reactor powering the Nautilus was a pressurized water reactor (PWR) built by Westinghouse. have a half-life In the pool type, the primary coolant is entirely contained in the main reactor vessel, which therefore includes not only the reactor core but also a heat exchanger. �-���wo�H댘�0�b���3�����g�_S�+���0Z����O�:�K e� <> Inside a fast reactor Liquid sodium from heat exchanger heats water in a steam generator Steam drives a turbine to generate electricity Liquid sodium pumped through baffle to be heated by reactor core Baffle coolant (sodium) Pump SOURCE: GE HITACHI Heated sodium passes through a heat exchanger. The acronym SFR particularly refers to two Generation IV reactor proposals, one based on existing liquid metal cooled reactor (LMFR) technology using mixed oxide fuel (MOX), the other based on the metal-fueled integral fast reactor. ‡  over 200 ka: Long-lived fission product, The operating temperature should not exceed the melting temperature of the fuel. The second is a medium to large (500–1,500 MWe) sodium-cooled reactor with mixed uranium-plutonium oxide fuel, supported by a fuel cycle based upon advanced aqueous processing at a central location serving a number of reactors. Highly powerful reactors seems to be one way to do it. Seawolf traveled over 71,000 miles on her sodium-cooled plant, and interestingly not one single reactor compartment entry was made during the roughly two year time span in which the SIR Mark B, later known as S2G plant was operated. Russia built 248 nuclear submarines and five naval surface vessels (plus nine icebreakers) powered by 468 reactors between 1950 and 2003, and was then operating about 60 nuclear naval vessels. Seawolf was built by the Electric Boat Division of General Dynamics in Groton, Conn., and commissioned on March 30, 1957. The … in the range of No fission products m  metastable isomer 1.1.1 Modeling of precipitation of oxides and hydrides in a Cold trap (Contact person: Shri M.G. A design work-around has been proposed to have an inert matrix. ₡  has thermal neutron capture cross section in the range of 8–50 barns Was used to power a water de-salination plant. She was the U.S. Navy ’s second nuclear submarine. The amount of transuranic transmutation is limited by the production of plutonium from uranium. During a discussion of the SIR or Submarine Intermediate Reactor, the sodium cooled submarine plant, Rickover said the following on the record: "At the time we started working on the nuclear propulsion program, sir, we went to two equivalent approaches. In fact, there were two nuclear powerplants being developed simultaneously: a pressurised water reactor (PWR) by Westinghouse and a more efficient Sodium-cooled reactor by General Electric. Does not include submarine (S1G/S2G) or space reactors (SNAP). When creating the new nuclear Navy in the 1950s, then-Captain Hyman Rickover determined that two types of reactor power plants would be evaluated to power submarines, a water cooled reactor and a molten sodium cooled reactor. In the loop type, the heat exchangers are external to the reactor tank. Water is a much stronger neutron moderator because the hydrogen atoms found in water are much lighter than metal atoms, and therefore neutrons lose more energy in collisions with hydrogen atoms. If sodium comes into contact with water it reacts to produce sodium hydroxide and hydrogen, and the hydrogen burns when in contact with air. Sodium has a melting … The concept is generally very similar to sodium-cooled fast reactor, and most liquid-metal reactors have used sodium instead of lead. Magnesium oxide has an entire order of magnitude smaller probability of interacting with neutrons (thermal and fast) than elements like iron. Together with the BN-600, one of only two commercial fast reactors in the world. The sodium-cooled fast reactor (SFR) Gen IV system is considered to be the design with the greatest maturity for the burning of minor actinides (MA) because fast spectrum neutrons generally have a greater probability for the fission of MA than thermal. [2] Sodium also need not be pressurized since its boiling point is much higher than the reactor's operating temperature, and sodium does not corrode steel reactor parts. This makes it difficult to use water as a coolant for a fast reactor because the water tends to slow (moderate) the fast neutrons into thermal neutrons (though concepts for reduced moderation water reactors exist). This page was last edited on 25 December 2020, at 15:50. 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