First published 1999-12-28
Beloyarsk Nuclear Power Plant
Beloyarsk Nuclear Power Plant has the worlds largest fast-breeder reactor in operation. Since it was put in operation in 1980, there have been several grave incidents with this reactor. It has also been registered an increase of radioactivity in the areas surrounding the power plant.
Beloyarsk Nuclear Power Plant is situated by the city Zarechnij, in the Sverdlovsk region. The closest larger city is Yekaterinburg. The power plant was the first to put graphite-moderated reactors in operation, to produce electrical power. These reactors have now been shut down.
One of the reactors that are operational today at Beloyarsk Power Plant, is a BN-600 fast-breeder reactor, which has an effect of 600 MW. This is the larger of the two fast-breeder reactors that are in commercial use today. The other one is situated in Kazhakstan. Both France and Japan have test versions of the fast-breeder reactor in operation. The construction of the BN-600 commenced in 1966, and the reactor was put in operation in 1980.
The reactor-core is 1.03 metres tall and has a diameter of 2.05 meter. It has 369 fuel-assemblies, which each consist of 127 fuel-pins with an enrichment of 17-26% 235U. In comparison, the normal enrichment in other Russian reactors is between 3-4% 235U. The BN-600 reactors use liquid sodium as coolant. There are three turbines connected to the reactor.
In 1987, the construction of a new and bigger fast-breeder reactor, the BN-800 type began. The work was stopped in 1988 after vigorous protests from the people living in the region. In 1992 President Yeltsin ordered the construction resumed, but due to lack of finances, very little has been done. Construction costs has been estimated to 1 trillion roubles.
The two first reactors at Beloyarsk Power Plant were put in operation in 1964 and 1967, respectively. They were shut down in 1983 and 1989. These were of the AMB-100 and AMB-200 type, which are an earlier version of RBMK graphite-moderated reactors.
Incidents and safety problems
The two gravest incidents at Beloyarsk Nuclear Power Plant struck the two oldest reactors, which now are shut down. In 1977 half of the heat-elements melted down in reactor ABM-200. The operators were exposed to severe radiation doses and the repair-work proceeded more than a year. In December 1978 the same reactor caught fire when parts of the roof fell down on one of the turbines oil tank. Control-cables were destroyed by fire, and the reactor came out of control. Eight people, whom assisted to secure the cooling of the reactor-core, were exposed to increased radiation doses.
In the recent years there has been problems with a leakage of liquid metal, from the BN-600s cooling system. In December 1992 there was a leakage of radioactive contaminated water at the reactor. In October 1993 it was uncovered increased concentrations of radioactivity in the power plants fan-system. A leakage the following month led to the shut down of this reactor.
In January and May 1994 there was a fire at the power plant. In July 1995 another leakage of liquid metal from the cooling-elements, caused a two-week shut down of the reactor.
There is an increasing concern about radioactive contamination around the power plant. There has been discovered several hotspots in the region that now is monitored.
Increasing interest For Beloyarsk
There is a lot of international interest for the fast-breeder reactor in Beloyarsk. Both Japan and France has their own fast-breeder reactor in operation, though only as test versions. Japan has paid 1 billion for the technical documentation on the reactor in Beloyarsk. It is an international study in progress where Russia, France, Japan and England participate. The study focuses on the technical problems with the fast-breeder reactor.
EECs Tacis program has granted 1.2 million ECU, for safety studies of the BN-600 reactor.