Prospect or suspect – uranium mining in AustraliA

Activity 3

The advantages and disadvantages of enriching uranium within Australia

Discussion about uranium in Australia does not end with the question of whether or not it should be mined. Further purification procedures are required to obtain a useful product. The stages between mining uranium ore and having a product for use in a nuclear reactor are:

  • milling (crushing and grinding);

  • leaching (dissolving the uranium and some other metals in sulfuric acid or similar solvent), with remaining solids being pumped to a tailings dam;

  • extraction of the dissolved uranium by a precipitation process to produce 'yellow cake' (uranium oxide);

  • concentration, where the yellow cake is purified and converted to uranium hexafluoride;

  • enrichment, where the proportion of the fissile uranium isotope is increased from about 0.7 to 3 per cent;

  • fuel fabrication, where uranium hexafluoride is converted to uranium dioxide and formed into pellets that can be loaded into fuel rods for the use in a reactor.

All these stages can release radioactive gases and dust unless precautions are taken. In addition, the solids left after leaching contain traces of the radioactive material from the original ore, so tailings must be buried.

At present ore mined in Australia is treated at the mine to the end of the extraction stage and uranium is then exported in the form of yellow cake, but some people argue that uranium ore should be enriched in Australia.

  • What are the advantages and disadvantages of carrying out enrichment in Australia?

Teachers notes

The following aspects of carrying out enrichment in Australia could be considered.

Advantages:

  • creates more employment;

  • adds value to the product and so increases the economic return;

  • reduces bulk and weight of material to be transported, so reduces transport costs and saves fuel;

  • Australia has more suitable sites than most countries in which to store stockpiled wastes.

Disadvantages:

  • increases the number of people in Australia who risk exposure to radiation;

  • increases the amount of radioactive waste that has to be stored in Australia.
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Posted February 1997.