The Anna reactor was a Polishresearch nuclear reactor of graphite-water design. Construction began in 1961 in a dedicated building in the Institute for Nuclear Research in Otwock near Warsaw. The Anna reactor was commissioned on June 12, 1963, thus becoming the second and eventually the third most powerful nuclear reactor in Poland (after Maria and Ewa).
The Anna reactor, was constructed of 14 by 14 cm graphite blocks, 245 cm long, which were arranged in an octagon with a diameter of 270 cm. The fuel was concentric tubes containing uranium enriched to 20%. According to the design assumptions, there could be a maximum of 25 fuel elements, however, most often 16 were worked on. The core was additionally surrounded by a reflector and had an external neutron source used for start-up. The purpose of the Anna reactor was scientific and research work, and for a certain period also small-scale production of radioisotopes.
Between 1964 and 1971, the Anna reactor was included in an international research program co-financed by the International Atomic Energy Agency. The purpose of the program was research in reactor physics, including studies of changes in neutron flux over time, operator training and exchange of operational experience.
In March 1972, the Anna reactor was extensively modified. In particular, the central part of the core was replaced, which was filled with natural uranium without a moderator (and thus becoming fast-neutron reactor). The outer part was a ring with a layout from the previous version. Modified reactor was named P-ANNA (short for Prędka Anna, meaning Fast Anna in Polish) and was used for research on fast neutrons.
The Anna reactor had a power of 10 kWthermal, its own control room and a separate reactor building, shared with the Agata reactor and the Helena subcritical reactor. The Anna reactor was a unit completely designed and built in Poland by Polish engineers and nuclear physicists. It operated on EK-10 nuclear fuel manufactured by the USSR. The reactor was decommissioned in the 1980s. The reactor hall, along with many pieces of equipment, is still[when?] located at the National Center for Nuclear Research in Otwock. The entire reactor body still[when?] exists, along with the control room and mostly dismantled auxiliary systems. After fuel removal and decontamination, further work with the Anna reactor was discontinued.
This article needs additional or more specific categories. Please help out by adding categories to it so that it can be listed with similar articles.(January 2023)
Related Research Articles
A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nuclear fission is passed to a working fluid, which in turn runs through steam turbines. These either drive a ship's propellers or turn electrical generators' shafts. Nuclear generated steam in principle can be used for industrial process heat or for district heating. Some reactors are used to produce isotopes for medical and industrial use, or for production of weapons-grade plutonium. As of 2022, the International Atomic Energy Agency reports there are 422 nuclear power reactors and 223 nuclear research reactors in operation around the world.
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.
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.
The RBMK 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. The channels also contain the coolant, and are surrounded by graphite.
A breeder reactor is a nuclear reactor that generates more fissile material than it consumes. Breeder reactors achieve this because their neutron economy is high enough to create more fissile fuel than they use, by irradiation of a fertile material, such as uranium-238 or thorium-232, that is loaded into the reactor along with fissile fuel. Breeders were at first found attractive because they made more complete use of uranium fuel than light water reactors, but interest declined after the 1960s as more uranium reserves were found, and new methods of uranium enrichment reduced fuel costs.
A fast-neutron reactor (FNR) or fast-spectrum reactor or simply a fast reactor is a category of nuclear reactor in which the fission chain reaction is sustained by fast neutrons, as opposed to slow thermal neutrons used in thermal-neutron reactors. Such a fast reactor needs no neutron moderator, but requires fuel that is relatively rich in fissile material when compared to that required for a thermal-neutron reactor. Around 20 land based fast reactors have been built, accumulating over 400 reactor years of operation globally. The largest of this was the Superphénix Sodium cooled fast reactor in France that was designed to deliver 1,242 MWe. Fast reactors have been intensely studied since the 1950s, as they provide certain decisive advantages over the existing fleet of water cooled and water moderated reactors. These are:
The light-water reactor (LWR) is a type of thermal-neutron reactor that uses normal water, as opposed to heavy water, as both its coolant and neutron moderator; furthermore a solid form of fissile elements is used as fuel. Thermal-neutron reactors are the most common type of nuclear reactor, and light-water reactors are the most common type of thermal-neutron 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 as of September 2021, China is on the verge of starting its TMSR-LF1 thorium MSR.
Nuclear fuel is material used in nuclear power stations to produce heat to power turbines. Heat is created when nuclear fuel undergoes nuclear fission.
Generation IV reactors are six nuclear reactor designs recognized by the Generation IV International Forum. The designs target improved safety, sustainability, efficiency, and cost.
A high-temperature gas-cooled reactor (HTGR), is a nuclear reactor that uses a 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 750 °C (1,380 °F). The reactor core can be either a "prismatic block" or a "pebble-bed" core. The high temperatures enable applications such as process heat or hydrogen production via the thermochemical sulfur–iodine cycle.
The gas-cooled fast reactor (GFR) system is a nuclear reactor design which is currently in development. Classed as a Generation IV reactor, it features a fast-neutron spectrum and closed fuel cycle for efficient conversion of fertile uranium and management of actinides. The reference reactor design is a helium-cooled system operating with an outlet temperature of 850 °C using a direct Brayton closed-cycle gas turbine for high thermal efficiency. Several fuel forms are being considered for their potential to operate at very high temperatures and to ensure an excellent retention of fission products: composite ceramic fuel, advanced fuel particles, or ceramic clad elements of actinide compounds. Core configurations are being considered based on pin- or plate-based fuel assemblies or prismatic blocks, which allows for better coolant circulation than traditional fuel assemblies.
A nuclear reactor core is the portion of a nuclear reactor containing the nuclear fuel components where the nuclear reactions take place and the heat is generated. Typically, the fuel will be low-enriched uranium contained in thousands of individual fuel pins. The core also contains structural components, the means to both moderate the neutrons and control the reaction, and the means to transfer the heat from the fuel to where it is required, outside the core.
The Molten-Salt Reactor Experiment (MSRE) was an experimental molten salt reactor research reactor at the Oak Ridge National Laboratory (ORNL). This technology was researched through the 1960s, the reactor was constructed by 1964, it went critical in 1965, and was operated until 1969. The costs of a cleanup project were estimated at about $130 million.
The University of Florida Training Reactor (UFTR), commissioned in 1959, is a 100 kW modified Argonaut-type reactor at the University of Florida in Gainesville, Florida. It is a light water and graphite moderated, graphite reflected, light water cooled reactor designed and used primarily for training and nuclear research related activities. The reactor is licensed by the Nuclear Regulatory Commission and is the only research reactor in Florida.
The Ewa Reactor was Poland's first research nuclear reactor. Its name was derived from the first letters of the Polish words: Eksperymentalny (Experimental), Wodny (Water), and Atomowy (Atomic) as a reference to Ève Curie.
The Maria reactor is Poland's second nuclear research reactor and is the only one still in use. It is located at Narodowe Centrum Badań Jądrowych (NCBJ) at Świerk-Otwock, near Warsaw and named in honor of Maria Skłodowska-Curie. It is the only reactor of Polish design.
The liquid fluoride thorium reactor is a type of molten salt reactor. LFTRs use the thorium fuel cycle with a fluoride-based molten (liquid) salt for fuel. In a typical design, the liquid is pumped between a critical core and an external heat exchanger where the heat is transferred to a nonradioactive secondary salt. The secondary salt then transfers its heat to a steam turbine or closed-cycle gas turbine.
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.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
