Reed Research Reactor
Encyclopedia
Nuclear reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
located on-campus at Reed College
Reed College
Reed College is a private, independent, liberal arts college located in southeast Portland, Oregon. Founded in 1908, Reed is a residential college with a campus located in Portland's Eastmoreland neighborhood, featuring architecture based on the Tudor-Gothic style, and a forested canyon wilderness...
in Portland, OR
Portland, Oregon
Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...
. It is a pool-type TRIGA
TRIGA
TRIGA is a class of small nuclear reactor designed and manufactured by General Atomics. The design team for TRIGA was led by the physicist Freeman Dyson.TRIGA is the acronym of Training, Research, Isotopes, General Atomics.-Design:...
Mark I reactor, built by General Atomics
General Atomics
General Atomics is a nuclear physics and defense contractor headquartered in San Diego, California. General Atomics’ research into fission and fusion matured into competencies in related technologies, allowing the company to expand into other fields of research...
in 1968 and operated since then under licence from the Nuclear Regulatory Commission
Nuclear Regulatory Commission
The Nuclear Regulatory Commission is an independent agency of the United States government that was established by the Energy Reorganization Act of 1974 from the United States Atomic Energy Commission, and was first opened January 19, 1975...
. Maximum thermal output is 500 kW. The reactor has over 1,000 visitors each year and serves the Reed College
Reed College
Reed College is a private, independent, liberal arts college located in southeast Portland, Oregon. Founded in 1908, Reed is a residential college with a campus located in Portland's Eastmoreland neighborhood, featuring architecture based on the Tudor-Gothic style, and a forested canyon wilderness...
departments of Physics, Chemistry, and others.
Operation
RRR is the only research reactor in the world that is owned and operated by an undergraduate educational institution. It is operated and maintained primarily by undergraduate college students under the supervision of a director and associate director who are members of the college staff. The facility provides scientific irradiation services to a broad community outside the college, but its primary mission is for student initiated research, training, and hands-on education.RRR is a research reactor that is intended to produce thermal neutrons. It is used primarily for 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...
to produce radioisotopes or analyze composition of material samples.
Undergraduate leadership
The RRR distinguishes itself from other university research reactorResearch 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 by the fact that it is the only reactor run completely by undergraduate students and serves undergraduate degree programs almost exclusively. In fact, Reed College
Reed College
Reed College is a private, independent, liberal arts college located in southeast Portland, Oregon. Founded in 1908, Reed is a residential college with a campus located in Portland's Eastmoreland neighborhood, featuring architecture based on the Tudor-Gothic style, and a forested canyon wilderness...
does not have any nuclear engineering
Nuclear engineering
Nuclear engineering is the branch of engineering concerned with the application of the breakdown as well as the fusion of atomic nuclei and/or the application of other sub-atomic physics, based on the principles of nuclear physics...
or even any engineering
Engineering
Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes that safely realize improvements to the lives of...
program.
The facility still is host to research projects and is heavily used by the campus. As of May 2008, there are 46 students licensed to operate the reactor.
When the facilities were visited by ABC
American Broadcasting Company
The American Broadcasting Company is an American commercial broadcasting television network. Created in 1943 from the former NBC Blue radio network, ABC is owned by The Walt Disney Company and is part of Disney-ABC Television Group. Its first broadcast on television was in 1948...
's "Radioactive Roadtrip" Primetime special, the fact that the school had no Engineering program was purported as evidence that university reactors are sometimes kept as more of a status symbol than as a valid research tool. This is a quote from the ABC website:
University Reaction: The reactor is a "zero-risk facility," and there is no plausible way it is a threat, said Edward Hershey, director of public affairs at Reed College. Although the school has no nuclear engineering department — or any engineering department for that matter — chemistry and physics students use it as a resource. Hershey said the reactor is a "bragging point" for Reed. "It's just a neat facility," he said.
The "zero-risk facility" comment reflects the reactor design which is a pin-type Low Enriched Uranium natural circulation driven LWR, with a very strong negative temperature coefficient. As such, it is impossible to overheat the reactor, even in the case of a sudden reactivity insertion.
Irradiation Facilities
Irradiation facilities include equipment that is used to place, move, and organize samples that are to be irradiated.Pneumatic Transfer System
The pneumatic transfer system (known colloquially as the "rabbit system") consists of an irradiation chamber in the outer ring of the core with its associated pump and piping. This allows samples to be transferred in and out of the reactor core very rapidly, while the reactor is at power. Routine use of the pneumatic transfer system involves placing samples into vials, which in turn are placed in special capsules known as “rabbits.” The capsule is loaded into the system in the radiochemistry laboratory next to the reactor and is then transferred pneumatically into the core-irradiation position for a predetermined time. At the end of this period, the sample is transferred back to the receiving terminal, where it is removed for measurement. The transfer time from the core to the terminal is less than seven seconds, making this method of irradiating samples particularly useful for experiments involving radioisotopes with short half-lives. The flux in the core terminal is approximately 5x1012 n/cm2/s when the reactor is at full power.Rotating Specimen Rack
The rotating specimen rack (lazy susan) is located in a well on top of the graphite reflector which surrounds the core. The rack consists of a circular array of 40 tubular receptacles. Each receptacle can accommodate two TRIGA-type irradiation tubes, so that up to 80 separate samples may be irradiated at any one time. Vials holding up to 17 ml (2.57 cm internal diameter, 10 cm long) are routinely used in this system. Depending upon its geometry, a sample up to about 40 ml could be irradiated by joining two vials. Samples are loaded in the specimen rack prior to the start-up of the reactor. The rack automatically rotates during irradiation to ensure each sample receives the same neutron flux. Typically, the rotating rack is used by researchers when longer irradiation times (generally greater than five minutes) are required. The average thermal neutron flux in the rotating rack position is approximately 2x1012 n/cm2/s with a cadmium ratio of 6.0 at full power. The specimen rack can also be used for gamma irradiations when the reactor is shutdown. The shutdown gamma flux in the specimen rack is approximately 3 R/min.Central Thimble
The central thimble, which is a water-filled irradiation chamber about 3 cm in diameter, provides the highest available neutron flux, about 1.4x1013 n/cm2/s. However, it holds only one specially positioned irradiation container, containing a cavity 7.5 cm in length and 2.57 cm in diameter.Another in-core location is available by replacing one of the fuel elements with an irradiation chamber. The chamber fits into a fuel-element position within the core itself.
Foil-insertion holes, 0.798 cm in diameter, are drilled at various positions through the grid plates. These holes allow inserting special holders containing flux wires into the core, to obtain neutron flux maps of the core.