UNGG reactor

Nuclear reactors UNGG series (French Uranium Naturel Graphite Gaz, natural uranium graphite gas ') were built in France and Spain. The gas-cooled reactors in France program originally consisted of eight operated with natural uranium gas-cooled graphite-moderated reactors and the first generation. They are now all off. All eight reactors together had a net output of 2375 MWe and were aggregated 163 years in operation.

The natural uranium reactors use graphite as a moderator and carbon dioxide (CO2 ) under pressure as the coolant. In the French reactors, the reactor core consisting of a stack of graphite bricks in hexagonal form. Through each brick led a channel. In each of these channels the fuel was placed in the form of cassettes, wherein the gas circulated.

The French experience in operating gas-cooled reactors began in 1959 with the commissioning of the G2 reactor nuclear power plant in Marcoule.

The type of reactor has been developed jointly by the Commissariat à l' énergie Atomique (CEA ) and Electricité de France (EDF). The first UNGG reactor, the G1 in Marcoule, was put into operation in 1956. The last, Bugey 1, followed in 1972.

Both in France and in Spain it came in a UNGG each reactor of the most serious accident in a country's history. In France, took place on 17 October 1969, at March 13, 1980 accident (INES 4) in the reactors at the nuclear power plant Saint- Laurent, in which there was partial core meltdown, October 19, 1989 occurred in the reactor in a Vandellòs severe accident, in which the block was irreparably damaged, and he had to be shut down.

End of the 1960s, EDF decided to waive the UNGG series and build only pressurized water reactors from that date.

To shut down the UNGG reactors at Chinon, Bugey and Saint- Laurent, EDF chose partial or final dismantling that has lasted for decommissioning. In France, in Marcoule a recycling plant for steel from dismantled nuclear facilities under construction. This metal is expected to be radioactively contaminated, but can be recycled for other nuclear power plants.

Locations

On the following nuclear power plant sites UNGG reactors were in operation ( pcs):

• Bugey ( 1)
• Quinone ( 3)
• Marcoule ( 3)
• Saint -Laurent ( 2)
• Vandellòs ( 1)