Graphite-moderated reactor
type of nuclear 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
Hanford N-Reactor (dual use)
ADE-2 (dual use)
High-temperature gas-cooled reactors (past)
Dragon reactor
AVR
Peach Bottom Unit 1
THTR-300
Fort St. Vrain Generating Station
High temperature gas-cooled reactors (in development or construction)
Pebble-bed reactor
Very high temperature reactor
Prismatic fuel reactor
UHTREX Ultra-high-temperature reactor experiment
Other
Molten salt reactor
Research reactors
There have been a number of research or test reactors built that use graphite as the moderator.
Chicago Pile-1
Chicago Pile-2
Transient Reactor Test Facility (TREAT)
Molten Salt Reactor Experiment (MSRE)
History
The first artificial nuclear reactor, Chicago Pile-1, a graphite-moderated device that produced between 0.5 watts and 200 watts , was constructed by a team led by Enrico Fermi in 1942. The construction and testing of this reactor (an "atomic pile") was part of the Manhattan Project. This work led to the construction of the X-10 Graphite Reactor at Oak Ridge National Laboratory, which was the first nuclear reactor designed and built for continuous operation, and began operation in 1943.
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