Advanced Test Reactor

Advanced Test Reactor

Advanced Test Reactor

Idaho National Laboratory

Operating Institution Idaho National Laboratory
Location Butte County, near Arco, Idaho, United States
Coordinates 43°35′09″N 112°57′49″W / 43.58583°N 112.96361°W / 43.58583; -112.96361Coordinates: 43°35′09″N 112°57′49″W / 43.58583°N 112.96361°W / 43.58583; -112.96361
Power 250 MW
Construction and Upkeep
Construction Began 1967
Technical Specifications
Max Thermal Flux 1015 s−1 cm−2
Max Fast Flux 5·1014 s−1 cm−2
Cooling Light water
Neutron Moderator Light water
Neutron Reflector Beryllium
Cladding Material Stainless steel and concrete

The Advanced Test Reactor (ATR) is a research reactor at the Idaho National Laboratory, located east of Arco, Idaho. This reactor is primarily designed and used to test materials to be used in larger-scale and prototype reactors. It can operate at a maximum power of 250 MW and has a "Four Leaf Clover" design (similar to the Camunian rose) that allows for a variety of testing locations. The unique design allows for different flux in various locations and specialized systems also allow for certain experiments to be run at their own temperature and pressure.

The ATR is ordinary (light) water moderated and cooled, with a beryllium neutron reflector. It is pressurized and housed in a stainless steel tank.

As well as its role in materials irradiation work, ATR is the USA's only source of Cobalt-60 for medical applications.

History

ATR core, powered up. The serpentine arrangement of fuel plates can be seen glowing bright blue (Cherenkov radiation).

Since 1951, fifty-two reactors have been built on the grounds of what was originally the Atomic Energy Commission’s National Reactor Testing Station, currently the location of Idaho National Laboratory (INL). Constructed in 1967, the ATR is the second-oldest of three reactors still in operation at the site.[1] Its primary function is to intensely bombard samples of materials and fuels with neutrons to simulate long-term exposure to high levels of radiation, as would be present in a commercial nuclear reactor. The ATR is one of only four test reactors in the world with this capability.[2] The reactor also produces rare isotopes for use in medicine and industry.[3]

National Scientific User Facility

In April 2007, the ATR was designated a "National Scientific User Facility" to encourage use of the reactor by universities, laboratories, and industry.[4] This status is intended to stimulate experiments to extend the life of existing commercial reactors and encourage nuclear power development. These experiments will test "materials, nuclear fuel, and instruments that operate in the reactors."[2] Under this program, experimenters will not have to pay to perform experiments at the reactor, but are required to publish their findings. The interest from the academic community was seen at the 2009 ATR NSUF User's Week Conference, held in Idaho Falls, that attracted 32 different universities. There were five different university experiments assigned to the ATR in 2008, and another two in 2009.[5]

ATR compared with commercial reactors

Test reactors are very different in appearance and design from commercial, nuclear power reactors. Commercial reactors are large, operate at high temperature and pressure, and require a large amount of nuclear fuel. A typical commercial reactor has a volume of 48 cubic meters with 5400 kg of uranium at 288 °C (550 °F) and 177 atm.[3] Because of their large size and stored energy, commercial reactors require a robust "containment structure" to prevent the release of radioactive material in the event of an emergency situation.

By contrast, the ATR requires a smaller containment structure—it has a volume of 1.4 cubic meters, contains 43 kg of uranium, and operates at 60 °C (140 °F) and 26.5 atm (conditions similar to a water heater).[3] The reactor vessel itself, which is made of stainless steel surrounded by concrete that extends more than 20 feet (6.1 m) underground, is hardened against accidental or intentional damage. The entire reactor area is also surrounded by a confinement structure (as opposed to a "containment structure") designed to further protect the surrounding environment from any potential release of radioactivity.

Reactor design and experimental capabilities

The ATR core is designed to be as flexible as possible for research needs. It can be brought online and powered down safely as often as necessary to change experiments or perform maintenance. The reactor is also powered down automatically in the event of abnormal experimental conditions or power failure.

Components of the reactor core are replaced as necessary every 7–10 years to prevent fatigue due to exposure to radiation and to ensure experimenters always have a new reactor to work with. The neutron flux provided by the reactor can be either constant or variable, and each lobe of the four-leaf-clover design can be controlled independently to produce up to 1015 thermal neutrons per second per square centimeter or 5·1014 fast neutrons s−1 cm−2.[6] There are 77 different testing locations inside the reflector and another 34 low-intensity locations outside the core (see figure at right), allowing many experiments to run simultaneously in different test environments.[7] Test volumes up to 5.0 inches (130 mm) in diameter and 4 feet (1.2 m) long can be accommodated. Experiments are changed on average every seven weeks, and the reactor is in nominal operation (110 MW) 75% of the year.[8]

Three types of experiments can be performed in the reactor:[8]

Very limited monitoring and temperature control are available for the static capsule configuration, and any instances would have to be built into the capsule experiment (such as temperature melt wires or an insulating air gap).

Research experiments at the reactor include:

References

  1. ↑ "INL's 52 Reactors". Idaho National Laboratory. Retrieved 2008-02-28.
  2. 1 2 "Idaho test reactor opens to universities". USA Today. 2007-12-08. Retrieved 2008-02-29.
  3. 1 2 3 "ATR Factsheet" (PDF). Idaho National Laboratory. Retrieved 2008-02-28.
  4. ↑ "ATR Home Page". Idaho National Laboratory. Retrieved 2008-02-29.
  5. ↑ INL.gov
  6. ↑ "Advanced Test Reactor Testing Experience: Past, Present and Future" (PDF). Idaho National Laboratory. Retrieved 2008-03-28.
  7. ↑ "ATR National Science User Facility". Idaho National Laboratory. Retrieved 2008-02-29.
  8. 1 2 Frances Marshall. "ATR Irradiation Facilities and Capabilities" (PDF). Idaho National Laboratory. Retrieved 2008-02-29.
  9. 1 2 3 Robert C. Howard. "Reactor Utilization for the Advanced Test Reactor" (PDF). Idaho National Laboratory. Retrieved 2008-04-03.

External links

Media related to Advanced Test Reactor at Wikimedia Commons

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