|
Graphite Moderated Reactor
:''"Graphite reactor" directs here. For the graphite reactor at Oak Ridge National Laboratory, see X-10 Graphite Reactor.'' A graphite-moderated reactor is a nuclear reactor that uses carbon as a neutron moderator, which allows natural uranium to be used as nuclear fuel. The first artificial nuclear reactor, the Chicago Pile-1, used nuclear graphite as a moderator. Graphite-moderated reactors were involved in two of the best-known nuclear disasters: an untested graphite annealing process contributed to the Windscale fire (but the graphite itself did not catch fire), while a graphite fire during the Chernobyl disaster contributed to the spread of radioactive material. Types Several types of graphite-moderated nuclear reactors have been used in commercial electricity generation: *Gas-cooled reactors **Magnox **UNGG reactor ** Advanced gas-cooled reactor (AGR) *Water-cooled reactors **RBMK **MKER **EGP-6 *High-temperature gas-cooled reactors (past) **Dragon reactor ** AVR ** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Reactor Uranium Pile (30502443888)
Nuclear may refer to: Physics Relating to the nucleus of the atom: * Nuclear engineering *Nuclear physics *Nuclear power *Nuclear reactor *Nuclear weapon *Nuclear medicine *Radiation therapy *Nuclear warfare Mathematics *Nuclear space *Nuclear operator *Nuclear congruence *Nuclear C*-algebra In the mathematical field of functional analysis, a nuclear C*-algebra is a C*-algebra A such that the injective and projective C*- cross norms on A \oplus B are the same for every C*-algebra B. This property was first studied by under the name " ... Biology Relating to the Cell nucleus, nucleus of the cell: * Nuclear DNA Society *Nuclear family, a family consisting of a pair of adults and their children Music *Nuclear (band), "Nuclear" (band), group music. *Nuclear (Ryan Adams song), "Nuclear" (Ryan Adams song), 2002 *"Nuclear", a song by Mike Oldfield from his ''Man on the Rocks'' album *Nu.Clear (EP), ''Nu.Clear'' (EP) by South Korean girl group CLC See also *Nucleus (disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RBMK
The RBMK (russian: реактор большой мощности канальный, РБМК; ''reaktor bolshoy moshchnosti kanalnyy'', "high-power channel-type reactor") is a class of graphite-moderated nuclear power reactor designed and built by the Soviet Union. The name refers to its design where, instead of a large steel pressure vessel surrounding the entire core, the core is surrounded by a cylindrical annular steel tank inside a concrete vault and each fuel assembly is enclosed in an individual 8 cm (inner) diameter pipe (called a "technological channel"). The channels also contain the coolant, and are surrounded by graphite. The RBMK is an early Generation II reactor and the oldest commercial reactor design still in wide operation. Certain aspects of the original RBMK reactor design, such as the large positive void coefficient, the 'positive scram effect' of the control rods and instability at low power levels, contributed to the 1986 Chernobyl disaster, in which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transient Reactor Test Facility
The Transient Reactor Test Facility (TREAT) is an air-cooled, graphite moderated, thermal spectrum test nuclear reactor designed to test reactor fuels and structural materials. Constructed in 1958, and operated from 1959 until 1994, TREAT was built to conduct transient reactor tests where the test material is subjected to neutron pulses that can simulate conditions ranging from mild transients to reactor accidents. TREAT was designed by Argonne National Laboratory, and is located at the Idaho National Laboratory. Since original construction, the facility had additions or systems upgrades in 1963, 1972, 1982, and 1988. The 1988 addition was extensive, and included upgrades of most of the instrumentation and control systems. The U.S. Department of Energy (DOE) decided to resume a program of transient testing, and planned to invest about $75 million to restart the TREAT facility by 2018. The renewed interest in TREAT was sparked by the 2011 Fukushima Daiichi nuclear disaster, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molten Salt Reactor
A molten salt reactor (MSR) is a class of nuclear fission reactor in which the primary nuclear reactor coolant and/or the fuel is a molten salt mixture. Only two MSRs have ever operated, both research reactors in the United States. The 1950's Aircraft Reactor Experiment was primarily motivated by the compact size that the technique offers, while the 1960's Molten-Salt Reactor Experiment aimed to prove the concept of a nuclear power plant which implements a thorium fuel cycle in a breeder reactor. Increased research into Generation IV reactor designs began to renew interest in the technology, with multiple nations having projects, and , China is on the verge of starting its TMSR-LF1 thorium MSR. MSRs are considered safer than conventional reactors because they operate with fuel already in a molten state, and in some designs in the event of an emergency, the fuel mixture is designed to drain from the core to a containment vessel where it will solidify in fuel drain tanks. This pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UHTREX
The Ultra-High Temperature Reactor Experiment (UHTREX) was an experimental gas-cooled nuclear reactor run at Los Alamos National Laboratory between 1959 and 1971The Bradbury Years from '''' Winter/Spring 1983 ().The Agnew Years from ''Los Alamos Science'' Winter/Spring 1983 (Los Alamos Scientific Laboratory). as part of research into reducing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prismatic Fuel Reactor
A gas-cooled reactor (GCR) is a nuclear reactor that uses graphite as a neutron moderator and a gas (carbon dioxide or helium in extant designs) as coolant. Although there are many other types of reactor cooled by gas, the terms ''GCR'' and to a lesser extent ''gas cooled reactor'' are particularly used to refer to this type of reactor. The GCR was able to use natural uranium as fuel, enabling the countries that developed them to fabricate their own fuel without relying on other countries for supplies of enriched uranium, which was at the time of their development in the 1950s only available from the United States or the Soviet Union. The Canadian CANDU reactor, using heavy water as a moderator, was designed with the same goal of using natural uranium fuel for similar reasons. Design considerations Historically thermal spectrum graphite moderated gas cooled reactors mostly competed with light water reactors, ultimately losing out to them after having seen some deployment in B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Very High Temperature Reactor
A high-temperature gas-cooled reactor (HTGR), is a nuclear reactor that uses a graphite-moderated reactor, graphite moderator with a once-through uranium fuel cycle. The HTGR is a type of high-temperature reactor (HTR) that can conceptually have an outlet temperature of . The nuclear reactor core, reactor core can be either a "prismatic block" (reminiscent of a conventional reactor core) or a "Pebble-bed reactor, pebble-bed" core. The high temperatures enable applications such as process heat or hydrogen production via the thermochemical sulfur–iodine cycle. The HTR is the predecessor of the Very-high-temperature reactor (VHTR), one of the future Generation IV reactor-models, which initially would work with temperatures of 750 to 950 °C. Overview The HTGR is a type of high-temperature reactor that conceptually can reach high outlet temperatures (up to 750 °C). There are two main types of HTGRs: pebble bed reactors (PBR) and prismatic block reactors (PMR).The pri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pebble-bed Reactor
The pebble-bed reactor (PBR) is a design for a graphite- moderated, gas-cooled nuclear reactor. It is a type of very-high-temperature reactor (VHTR), one of the six classes of nuclear reactors in the Generation IV initiative. The basic design of pebble-bed reactors features spherical fuel elements called pebbles. These tennis ball-sized pebbles (approx. in diameter) are made of pyrolytic graphite (which acts as the moderator), and they contain thousands of micro-fuel particles called TRISO particles. These TRISO fuel particles consist of a fissile material (such as 235U) surrounded by a ceramic layer coating of silicon carbide for structural integrity and fission product containment. In the PBR, thousands of pebbles are amassed to create a reactor core, and are cooled by a gas, such as helium, nitrogen or carbon dioxide, that does not react chemically with the fuel elements. Other coolants such as FLiBe (molten fluoride, lithium, beryllium salt)) have also been suggeste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fort St
A fortification is a military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region during peacetime. The term is derived from Latin ''fortis'' ("strong") and ''facere'' ("to make"). From very early history to modern times, defensive walls have often been necessary for cities to survive in an ever-changing world of invasion and conquest. Some settlements in the Indus Valley civilization were the first small cities to be fortified. In ancient Greece, large stone walls had been built in Mycenaean Greece, such as the ancient site of Mycenae (famous for the huge stone blocks of its 'cyclopean' walls). A Greek '' phrourion'' was a fortified collection of buildings used as a military garrison, and is the equivalent of the Roman castellum or English fortress. These constructions mainly served the purpose of a watch tower, to guard certain roads, passes, and borders. Though smaller than a real fortress, they a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
THTR-300
The THTR-300 was a thorium cycle high-temperature nuclear reactor rated at 300 MW electric (THTR-300) in Hamm-Uentrop, Germany. It started operating in 1983, synchronized with the grid in 1985, operated at full power in February 1987 and was shut down September 1, 1989. The THTR-300 served as a prototype high-temperature reactor (HTR) to use the TRISO pebble fuel produced by the AVR, an experimental pebble bed operated by VEW (Vereinigte Elektrizitätswerke Westfalen). The THTR-300 cost €2.05 billion and was predicted to cost an additional €425 million through December 2009 in decommissioning and other associated costs. The German state of North Rhine Westphalia, Federal Republic of Germany, and Hochtemperatur-Kernkraftwerk GmbH (HKG) financed the THTR-300’s construction. History On 4 June 1974, the Council of the European Communities established the Joint Undertaking "Hochtemperatur-Kernkraftwerk GmbH" (HKG). The electrical generation part of the THTR-300 was finishe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peach Bottom Nuclear Generating Station
Peach Bottom Atomic Power Station, a nuclear power plant, is located southeast of Harrisburg in Peach Bottom Township, York County, Pennsylvania, on the Susquehanna River three miles north of the Maryland border. The Philadelphia Electric Company (later "PECO") was a pioneer in the commercial nuclear industry when it ordered Peach Bottom 1 in 1958. The U.S.'s first nuclear power plant (the Shippingport Reactor) had gone on line a year earlier. Peach Bottom Unit 1 was an experimental helium-cooled, graphite-moderated reactor. It operated from 1966 to 1974. Peach Bottom 2 and 3, General Electric boiling water reactors, went on-line in 1974, and are still in operation on the 620-acre (2.5 km2) site today. Both Units 2 and 3, originally rated at 3,514 megawatts thermal (MWth), equivalent to about 1,180 megawatts of electricity (MWe) each, were uprated to 4,016 megawatts thermal (MWth), equivalent to about 1,382 megawatts net of electricity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AVR Reactor
The AVR reactor (german: Arbeitsgemeinschaft Versuchsreaktor) was a prototype pebble-bed reactor, located immediately adjacent to Jülich Research Centre in West Germany, constructed in 1960, grid connected in 1967 and shut down in 1988. It was a 15MWe, 46 MWt test reactor used to develop and test a variety of fuels and machinery. The AVR was based on the concept of a "Daniels pile" by Farrington Daniels, the inventor of pebble bed reactors. Rudolf Schulten is commonly recognized as the intellectual father of the reactor. A consortium of 15 community electric companies owned and operated the plant. Over its lifetime the reactor had many accidents, earning it the name "shipwreck." From 2011 to 2014, outside experts examined the historical operations and operational hazards and described serious concealed problems and wrongdoings in their final 2014 report. For example, in 1978 operators bypassed reactor shutdown controls to delay an emergency shutdown during an accident for six ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Graphite Moderated Reactor"){kind=spacer}
.svg "Click for more on -> Pebble-bed Reactor")
