school energy&environment

Uranium resources

When you talk of “retrievable” uranium, it means that it is possible to extract the mineral from a reservoir and make it available for a fuel element, at a specific price that is expressed in dollars. Analysing the world map of reservoirs and knowing their nature it is possible to assess the exploitable quantity of uranium by forming cost ranges: up to 40 $, between 40 $ and 80 $ and between 80 $ and 130 $. Obviously the most economical are the ones that are exploited first.
All areas where there is an attested presence of uranium are denominated Reasonably Assured Resources (RAR).
One the reasonably safe reservoirs are known, through analyses coupled with adeguate radioactive measures, similar areas in geomorphologic terms can be individuated in order to obtain information on reservoirs similar to the ones being exploited. These reservoirs are considered esteemed and are part of the Estimated Additional Resources (EAR, also known as Inferred Resources, IR).
These extra resources are classified in two categories: EAR-I and EAR-II; the EAR II are less certain than the first ones. There is also another category called Speculative Resources (SR), which derive from another extrapolation of the geomorphologic characteristics of land that could easily obtain uranium.
The RAR resource types are the easier ones to exploit, thus cheaper; they are available in quantities that go between 507,400 t and 4,587,200 t in relation to how much money is available for the extraction.
The data relating to the Estimated Additional Resources of the second group (EAR-II) are much more precise in comparison with those on Speculative Resources and the estimates are of a quantity of uranium equal to about 2,200,000 tons at a price between 80 $ and 130 $.
The Speculative Resources also include uranium in phosphates and it can be estimated in about 22,000,000 tons of uranium. If we add the uranium container in the oceans’ water we reach a quantity of uranium equal to about 4 billion tons!
The technology of uranium extraction from phosphates is essentially developed: it is already used in Belgium and the United States. However it has a limited diffusion because it is not economically convenient: it is estimated that an extraction project of 100 tU/year would have a cost in the range 60-100 $/kgU (inclusive of investment costs).
For what concerns the extraction of uranium from the sea, encouraging research has been undertaken in Japan: however, it is still a technology tested at laboratory level with very high costs, estimated around 300 $/kgU.