26 October 2007

How much Uranium is there in the world??

Commodity Online Special
Uranium is a relatively common metal, found in rocks and seawater. Economic concentrations of it are not uncommon.
Its availability to supply world energy needs is great both geologically and because of the technology for its use.

Quantities of mineral resources are greater than commonly perceived.

Uranium is ubiquitous on the Earth. It is a metal approximately as common as tin or zinc, and it is a constituent of most rocks and even of the sea.

An orebody is, by definition, an occurrence of mineralisation from which the metal is economically recoverable. It is therefore relative to both costs of extraction and market prices. At present neither the oceans nor any granites are orebodies, but conceivably either could become so if prices were to rise sufficiently.

Measured resources of uranium, the amount known to be economically recoverable from orebodies, are thus also relative to costs and prices. They are also dependent on the intensity of past exploration effort, and are basically a statement about what is known rather than what is there in the Earth's crust.

Changes in costs or prices, or further exploration, may alter measured resource figures markedly. At ten times the current price, seawater might become a potential source of vast amounts of uranium. Thus, any predictions of the future availability of any mineral, including uranium, which are based on current cost and price data and current geological knowledge are likely to be extremely conservative.

From time to time concerns are raised that the known resources might be insufficient when judged as a multiple of present rate of use. But this is the Limits to Growth fallacy, a major intellectual blunder recycled from the 1970s, which takes no account of the very limited nature of the knowledge we have at any time of what is actually in the Earth's crust. Our knowledge of geology is such that we can be confident that identified resources of metal minerals are a small fraction of what is there.

Australia has a substantial part (about 24 percent) of the world's low-cost uranium, Kazakhstan 17 percent, and Canada 9 percent.

Current usage is about 66,500 tU/yr. Thus the world's present measured resources of uranium (4.7 Mt) in the cost category somewhat above present spot prices and used only in conventional reactors, are enough to last for some 70 years. This represents a higher level of assured resources than is normal for most minerals. Further exploration and higher prices will certainly, on the basis of present geological knowledge, yield further resources as present ones are used up.

There was very little uranium exploration between 1985 and 2005, so the significant increase in exploration effort that we are now seeing could readily double the known economic resources. On the basis of analogies with other metal minerals, a doubling of price from present levels could be expected to create about a tenfold increase in measured resources, over time.

If those covering estimates of all conventional resources are considered - 10 million tonnes (beyond the 4.7 Mt known economic resources), which takes us to over 200 years' supply at today's rate of consumption. This still ignores the technological factor mentioned below. It also omits unconventional resources such as phosphate/ phosphorite deposits (22 Mt U recoverable as by-product) and seawater (up to 4000 Mt), which would be uneconomic to extract in the foreseeable future.

Widespread use of the fast breeder reactor could increase the utilisation of uranium 50-fold or more. This type of reactor can be started up on plutonium derived from conventional reactors and operated in closed circuit with its reprocessing plant. Such a reactor, supplied with natural or depleted uranium for its 'fertile blanket', can be operated so that each tonne of ore yields 60 times more energy than in a conventional reactor.

Courtesy: World Nuclear Association

Yes, and what about the poison ...???

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