Canada's nuclear fuel industry: An overview. Background paper

Canada was among the first countries to mine and process uranium-bearing ores. Such ores contain trace amounts of radium, which was in great demand for medical treatment and for use by research laboratories in the early part of the century. For the last half century, the same basic processes have been used to extract uranium from its ores and convert it to a form suitable for use in nuclear reactors. The process described here is that currently in use in Canada. Mining can take a variety of forms, from open-pit to deep, hard-rock. Mining is typically the most costly step in the process, particularly for lower-grade ores. The ore is crushed and ground in the mill to the consistency of fine sand from which the uranium is extracted chemically to produce the impure concentrate known as yellowcake. In the next step, the impure uranium concentrate is chemically refined into highly purified, nuclear-grade, uranium trioxide (UO3). Uranium trioxide is then converted, in two separate chemical processes, into uranium dioxide (UO2) which is destined for domestic consumption and uranium hexafluoride (UF6) which is exported. In Canada, fabrication is the final step of the fuel production process. Uranium dioxide powder is compressed and sintered into very dense ceramic pellets which are then sealed in zirconium tubes and assembled into fuel bundles for Candu reactors. This background paper will review the Canadian nuclear fuels industry. 1 fig