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Sodium-cooled Fast Reactor
A sodium-cooled fast reactor is a fast neutron reactor cooled by liquid sodium. The initials SFR in particular refer to two Generation IV reactor proposals, one based on existing liquid metal cooled reactor (LMFR) technology using mixed oxide fuel (MOX), and one based on the metal-fueled integral fast reactor. Several sodium-cooled fast reactors have been built and some are in current operation, particularly in Russia. Others are in planning or under construction. For example, in the US, TerraPower (using its Traveling Wave technology) is building its own reactors along with molten salt energy storage in partnership with GEHitachi's PRISM integral fast reactor design, under the ''Natrium'' appellation in Kemmerer, Wyoming. Aside from the Russian experience, Japan, India, China, France and the USA are investing in the technology. Fuel cycle The nuclear fuel cycle employs a full actinide recycle with two major options: One is an intermediate-size (150–600 MWe) sodium-cooled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium-24
There are 20 isotopes of sodium (11Na), ranging from to (except for the still-unknown 36Na and 38Na), and five isomers (two for , and one each for , , and ). is the only stable (and the only primordial) isotope. It is considered a monoisotopic element and it has a standard atomic weight of . Sodium has two radioactive cosmogenic isotopes (, with a half-life of ; and , with a half-life of ). With the exception of those two isotopes, all other isotopes have half-lives under a minute, most under a second. The shortest-lived is the unbound , with a half-life of seconds (although the half-life of the similarly unbound 17Na is not measured). Acute neutron radiation exposure (e.g., from a nuclear criticality accident) converts some of the stable (in the form of Na+ ion) in human blood plasma to . By measuring the concentration of this isotope, the neutron radiation dosage to the victim can be computed. is a positron-emitting isotope with a remarkably long half-life. It is used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water
Water is an inorganic compound with the chemical formula . It is a transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance. It is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a solvent). It is vital for all known forms of life, despite not providing food energy or organic micronutrients. Its chemical formula, , indicates that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds. The hydrogen atoms are attached to the oxygen atom at an angle of 104.45°. In liquid form, is also called "water" at standard temperature and pressure. Because Earth's environment is relatively close to water's triple point, water exists on Earth as a solid, a liquid, and a gas. It forms precipitation in the form of rain and aerosols in the form of fog. Clouds consist of suspended droplets of water and ice, its solid state. When finely divided, crystalline ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron Moderator
In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, ideally without capturing any, leaving them as thermal neutrons with only minimal (thermal) kinetic energy. These thermal neutrons are immensely more susceptible than fast neutrons to propagate a nuclear chain reaction of uranium-235 or other fissile isotope by colliding with their atomic nucleus. Water (sometimes called "light water" in this context) is the most commonly used moderator (roughly 75% of the world's reactors). Solid graphite (20% of reactors) and heavy water (5% of reactors) are the main alternatives. Beryllium has also been used in some experimental types, and hydrocarbons have been suggested as another possibility. Moderation Neutrons are normally bound into an atomic nucleus and do not exist free for long in nature. The unbound neutron has a half-life of 10 minutes and 11 seconds. The release of neutrons from the nucleus requires exceeding the binding ener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron
The neutron is a subatomic particle, symbol or , that has no electric charge, and a mass slightly greater than that of a proton. The Discovery of the neutron, neutron was discovered by James Chadwick in 1932, leading to the discovery of nuclear fission in 1938, the first self-sustaining nuclear reactor (Chicago Pile-1, 1942) and the first nuclear weapon (Trinity (nuclear test), Trinity, 1945). Neutrons are found, together with a similar number of protons in the atomic nucleus, nuclei of atoms. Atoms of a chemical element that differ only in neutron number are called isotopes. Free neutrons are produced copiously in nuclear fission and nuclear fusion, fusion. They are a primary contributor to the nucleosynthesis of chemical elements within stars through fission, fusion, and neutron capture processes. Neutron stars, formed from massive collapsing stars, consist of neutrons at the density of atomic nuclei but a total mass more than the Sun. Neutron properties and interactions ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transuranic Waste
Transuranic waste (TRU) is stated by U.S. regulations, and independent of state or origin, to be waste which has been contaminated with alpha emitting transuranic radionuclides possessing half-lives greater than 20 years and in concentrations greater than 100 nCi/g (3.7 MBq/kg). Elements having atomic numbers greater than that of uranium are called transuranic. Elements within TRU are typically man-made and are known to contain americium-241 and several isotopes of plutonium. Because of the elements' longer half-lives Half-life is a mathematical and scientific description of exponential or gradual decay. Half-life, half life or halflife may also refer to: Film * ''Half-Life'' (film), a 2008 independent film by Jennifer Phang * '' Half Life: A Parable for t ..., TRU is disposed of more cautiously than low level waste and intermediate level waste. In the U.S. it is a byproduct of weapons production, nuclear research and power production, and consists of protec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prototype Fast Reactor
Dounreay (; ) is a small settlement and the site of two large nuclear establishments on the north coast of Caithness in the Highland (council area), Highland area of Scotland. It is on the A836 road west of Thurso. The nuclear establishments were created in the 1950s. They were the Nuclear Power Development Establishment (NPDE), now known as NRS Dounreay, for the development of civil fast breeder reactors, and the Vulcan Naval Reactor Test Establishment, Vulcan Naval Reactor Test Establishment (NRTE), a military Nuclear marine propulsion, submarine reactor testing facility. Both these no longer perform their original research functions and will be completely decommissioned. The two establishments have been a major element in the economy of Thurso and Caithness, but this will decrease with the progress of decommissioning. NRS Dounreay will enter an interim care and surveillance state by 2036, and become a Brownfield land, brownfield site by 2336. An announcement in July 2020 tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rapsodie
Rapsodie was an experimental nuclear reactor built in Cadarache in France. It was France's first fast reactor, and first achieved criticality in 1967. Rapsodie was a sodium-cooled fast neutron loop-type reactor with a thermal output of 40MW and no electrical generation facilities, and closed in 1983. Rapsodie was operated in conditions considered representative of a commercial plant in terms of temperatures (inlet , outlet ) and neutron flux (3.2e15n/cm^2/s), and served to prove many elements used in later, larger, breeder reactors. Rapsodie operated for 15 years, and suffered two leaks, a sodium micro leak in 1978 that was so small it was never found, and a nitrogen gas leak in 1982. Rapsodie is currently in Stage 2 decommissioning. See also *Fast neutron reactor A fast-neutron reactor (FNR) or fast-spectrum reactor or simply a fast reactor is a category of nuclear reactor in which the fission nuclear chain reaction, chain reaction is sustained by fast neutrons (carrying ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CFR-600
The CFR-600 (Xiapu fast reactor pilot project) is a sodium-cooled pool-type fast-neutron nuclear reactor under construction in Xiapu County, Fujian province, China, on Changbiao Island. It is a generation IV demonstration project by the China National Nuclear Corporation (CNNC). Construction started in late 2017. These reactors are expected to be connected to the grid in 2023 and 2025. The reactor will have an output of 1500 MW thermal power and 600 MW electric power. The fuel will be supplied by TVEL, subsidiary of Rosatom, according to the agreement signed in 2019. The CFR-600 is part of the Chinese plan to reach a closed nuclear fuel cycle. Fast neutron reactors are the main future nuclear power technology in China. A larger commercial-scale reactor, the CFR-1000, is also planned. On the same site, the building of a second 600 MW fast reactor CFR-600 was started in December 2020 and four 1000 MW CAP1000 are proposed.CCCC-FHDI wins bid for quot;feasibility s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prototype Fast Breeder Reactor
The Prototype Fast Breeder Reactor (PFBR) is a 500 MWe sodium-cooled, fast breeder reactor that is being constructed at the same site as the Madras Atomic Power Station in Kokkilamedu, near Kalpakkam, in Tamil Nadu state, India. The Indira Gandhi Centre for Atomic Research (IGCAR) is responsible for the design of this reactor, the Advanced Fuel Fabrication Facility at the Bhabha Atomic Research Centre in Tarapur is responsible for MOX fuel fabrication and BHEL is providing technology and equipment for construction of the reactor. The facility builds on the decades of experience gained from operating the lower power Fast Breeder Test Reactor (FBTR). At first, the reactor's construction was supposed to be completed in September 2010, but there were several delays. The Prototype Fast Breeder Reactor is scheduled to be put into service in December 2024, which is more than 20 years after construction began and 14 years after the original commissioning date, as of December 2023 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phénix
Phénix (French for phoenix) was a small-scale (gross 264/net 233 MWe) prototype fast breeder reactor, located at the Marcoule nuclear site, near Orange, France. It was a pool-type liquid-metal fast breeder reactor cooled with liquid sodium. It generated 590 MW of thermal power, and had a breeding ratio of 1.16 (16% more plutonium produced than consumed), but normally had to be stopped for refueling operations every two months. Phénix continued operating after the closure of the subsequent full-scale prototype Superphénix in 1997. After 2004, its main use was investigation of transmutation of nuclear waste while also generating some electricity. Phénix was shut down in 2009.''PHENIX'' The [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EBR-2
Experimental Breeder Reactor-II (EBR-II) was a sodium-cooled fast reactor designed, built and operated by Argonne National Laboratory at the National Reactor Testing Station in Idaho. It was shut down in 1994. Custody of the reactor was transferred to Idaho National Laboratory after its founding in 2005. Initial operations began in July 1964 and it achieved criticality in 1965 at a total cost of more than US$32 million ($ in dollars). The original emphasis in the design and operation of EBR-II was to demonstrate a complete breeder-reactor power plant with on-site reprocessing of solid metallic fuel. Fuel elements enriched to about 67% uranium-235 were sealed in stainless steel tubes and removed when they reached about 65% enrichment. The tubes were unsealed and reprocessed to remove neutron poisons, mixed with fresh U-235 to increase enrichment, and placed back in the reactor. Testing of the original breeder cycle ran until 1969, after which time the reactor was used to test ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
