Heavy-Water Reactor

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Related to Heavy-Water Reactor: Fast breeder reactor, CANDU reactor

heavy-water reactor

[′hev·ē ¦wȯd·ər rē′ak·tər]
A nuclear reactor in which heavy water serves as moderator and sometimes also as coolant.

Heavy-Water Reactor


a thermal reactor in which heavy water (D20) serves as the moderator. Because heavy water has a small neutron capture cross section, a heavy-water reactor may contain an extremely large fraction of fuel in the process of being generated as the original fuel is burned; the ratio of the weight of newly produced fuel to that of the burned fuel may be as high as 0.9. Ordinary water, heavy water, and certain gases, for example, steam and carbon dioxide, are used as coolants in heavy-water reactors.

Table 4. Production of diesel engines in the USSR1
1 Excluding motor-vehicle and tractor engines
General-purpose diesels:    
units. . . . . . . . . . . . . . . . . . . . . .12,14054,32259,62765,235
total horsepower. . . . . . . . . . . . . . . . . . . . . .469,9008,830,70016,158,00018,230,600

Construction and operating costs of heavy-water reactors are high because of the price of heavy water. The reactors are therefore used in industry only in countries where heavy water can be produced relatively cheaply, such as in Canada, where the electric power supplied by the country’s hydroelectric power plants costs very little.

References in periodicals archive ?
Removing the core of the heavy-water reactor to produce less plutonium is a crucial step before the relief from sanctions starts.
A diplomat familiar with the negotiations said China was ready to help in modifying the heavy-water reactor at Arak, France in reprocessing nuclear waste and Britain in the field of nuclear safety and security.
UN nuclear inspectors who were banned earlier this year by Iran from visiting a heavy-water reactor will now be allowed to inspect it before the end of July, says the International Atomic Energy Agency.
Also in the letter, the intergovernmental body monitoring nuclear efforts around the world, also expressed concern that Iran may be moving ahead with work on its heavy-water reactor without submitting to inspections and other verification measures, as it had agreed to.
But the spent fuel from a heavy-water reactor can be reprocessed to extract plutonium for use in a bomb.
But in exchange, the Iranians would have to suspend totally and sine die any uranium enrichment activities and scrap plans to build a heavy-water reactor capable of producing plutonium.
Prior to the deal, it was repeatedly stated over the years that Iran's key facilities of Fordow, an underground uranium enrichment plant; and Arak, a heavy-water reactor suitable for plutonium production, would have to be shut down.
Secondly, with regard to the plutonium produced by any other reactor, such as Bushehr, there will be no reprocessing to extract plutonium, no reprocessing research and development, no other heavy-water reactor for at least 15 years, "and any excess heavy water will be sold on the international market," he said.
Iran says it is scaling down plutonium production plans at the nation's partially constructed heavy-water reactor, an announcement seen as a gesture toward negotiations with world powers over Iran's controversial nuclear program.
An explosion at Iran's heavy-water reactor will delay the construction of the controversial nuclear plant at Arak in western Iran, according to Israeli website Debkafile, which has close contacts with Mossad and other intelligence services in the Jewish state.
According to Banerjee, "We will add eight to ten 700-megawatt pressurized heavy-water reactors, several fast-breeder reactors and an advanced heavy-water reactor, all of indigenous design.
Iran has been a building a heavy-water reactor near the plant for two years, but the reactor is not scheduled for completion until 2009, the Associated Press reported.