MIT Nuclear Research Reactor
Encyclopedia
The MIT Nuclear Research Reactor (MITR) serves the research purposes of the Massachusetts Institute of Technology
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...

. It is a tank-type 6 MW reactor that is moderated and cooled by light water and uses heavy water
Heavy water
Heavy water is water highly enriched in the hydrogen isotope deuterium; e.g., heavy water used in CANDU reactors is 99.75% enriched by hydrogen atom-fraction...

 as a reflector. It is the second largest university based research reactor
Research reactor
Research reactors are nuclear reactors that serve primarily as a neutron source. They are also called non-power reactors, in contrast to power reactors that are used for electricity production, heat generation, or maritime propulsion.-Purpose:...

 in the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 (after the University of Missouri Research Reactor Center
University of Missouri Research Reactor Center
The University of Missouri Research Reactor Center is home to a tank-type nuclear research reactor that serves the University of Missouri's . The MURR is currently the highest power university research reactor in the U.S. at 10 megawatt thermal output...

) and has been in operation since 1958. It is the fourth-oldest operating reactor in the country.

Technical specifications

The MITR-II design uses finned plate-type fuel arranged in a hexagonal pattern of rhomboid
Rhomboid
Traditionally, in two-dimensional geometry, a rhomboid is a parallelogram in which adjacent sides are of unequal lengths and angles are oblique.A parallelogram with sides of equal length is a rhombus but not a rhomboid....

 fuel assemblies. Power is controlled by 6 manual boron-stainless steel blade-type control rod
Control rod
A control rod is a rod made of chemical elements capable of absorbing many neutrons without fissioning themselves. They are used in nuclear reactors to control the rate of fission of uranium and plutonium...

s and one aluminum with cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...

 control rod which can be placed on automatic control. Light water flows upwards through the core and a tank of heavy water surrounds the core. A wall of dense concrete that serves as shielding surrounds the tank of heavy water. The maximum coolant temperature is 55 degrees Celsius. The light water and heavy water are cooled through forced circulation through heat exchanger
Heat exchanger
A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact...

s; secondary coolant is cooled in two cooling tower
Cooling tower
Cooling towers are heat removal devices used to transfer process waste heat to the atmosphere. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or in the case of closed circuit dry cooling towers rely...

s.

The reactor uses highly enriched uranium fuel, in the form of uranium-aluminum cermet
Cermet
A cermet is a composite material composed of ceramic and metallic materials. A cermet is ideally designed to have the optimal properties of both a ceramic, such as high temperature resistance and hardness, and those of a metal, such as the ability to undergo plastic deformation. The metal is used...

 with aluminum cladding.

Refueling takes place 3 to 4 times every year. A single refueling consists of rearranging the assemblies in the core or a combination of rearranging and replacement of old assemblies with new ones. This is more frequent than both nuclear power plant
Nuclear power plant
A nuclear power plant is a thermal power station in which the heat source is one or more nuclear reactors. As in a conventional thermal power station the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity.Nuclear power plants are usually...

s, which may go 17 to 23 months between refueling outages when they rearrange the entire core and replace 1/3 to 1/2 of the core, and most research reactor
Research reactor
Research reactors are nuclear reactors that serve primarily as a neutron source. They are also called non-power reactors, in contrast to power reactors that are used for electricity production, heat generation, or maritime propulsion.-Purpose:...

s (particularly university reactors), many of which go decades without refueling due to the high energy density of nuclear fuel and infrequent use at high power levels.

Uses

The MITR research program encompasses most aspects of neutron science and engineering including nuclear medicine. Some of these activities are:
  • Boron neutron capture therapy
    Boron Neutron Capture Therapy
    Boron neutron capture therapy is an experimental form of radiotherapy that uses a neutron beam that interacts with boron injected into a patient...

  • Radiation synovectomy
    Synovectomy
    Synovectomy is the surgical removal of a part of the synovial membrane of a synovial joint.-Indications:It is one of the treatment options for certain diseases involving the synovium like:* Severe rheumatoid arthritis or juvenile idiopathic arthritis...

  • Neutron activation
    Neutron activation
    Neutron activation is the process in which neutron radiation induces radioactivity in materials, and occurs when atomic nuclei capture free neutrons, becoming heavier and entering excited states. The excited nucleus often decays immediately by emitting particles such as neutrons, protons, or alpha...

     analysis for the identification of air pollutants and isotope ratios in geological specimens
  • Fission engineering
  • Materials testing
  • Training
  • Neutron transmutation
    Nuclear transmutation
    Nuclear transmutation is the conversion of one chemical element or isotope into another. In other words, atoms of one element can be changed into atoms of other element by 'transmutation'...

     doping of silicon
    Silicon
    Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...



The MITR is one of only six facilities in the world to be engaged in patient trials for the use of boron neutron capture therapy
Boron Neutron Capture Therapy
Boron neutron capture therapy is an experimental form of radiotherapy that uses a neutron beam that interacts with boron injected into a patient...

 (BNCT) to treat both brain tumors
Glioblastoma multiforme
Glioblastoma multiforme is the most common and most aggressive malignant primary brain tumor in humans, involving glial cells and accounting for 52% of all functional tissue brain tumor cases and 20% of all intracranial tumors. Despite being the most prevalent form of primary brain tumor, GBMs...

 and skin cancer
Skin cancer
Skin neoplasms are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises...

. The MITR fission converter beam is the first to be designed for BNCT.

External links

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