A Toshiba and Westinghouse Electric company
UAM is working tirelessly to develop its business in what is considered a renaissance period for the nuclear industry. As part of its programme of self-analysis and improvement it continues to develop innovative solutions to material handling and transport issues to provide enhanced safety and also to deliver exceptional added value service for customers.
In addition, as part of its strategic development of the market, UAM continues to explore investment opportunities within the nuclear fuel cycle.
Uranium Fuel Cycle
The civil front end nuclear fuel cycle is a process of nuclear fuel and energy production, including research activities. The cycle consists of 4 stages:
Mining & Milling
Uranium is a radioactive element that occurs naturally in the earth’s surface. Uranium ores are mined, by either excavation or in situ techniques. At the mill the extracted ore is crushed and ground to a fine slurry which is leached to allow the separation of uranium from the waste rock. It is then precipitated as uranium oxide (U3O8) concentrate (yellowcake).
At the conversion facility, the uranium oxide concentrate is refined to uranium dioxide, which can be used as the fuel for those reactors that do not require enriched uranium. Most is then converted into uranium hexafluoride (UF6), ready for the enrichment plant.
U-235 (0.7% of natural uranium) is the isotope which, in most reactors, produces energy by fission. The concentration of this isotope needs to be enriched - typically to 3.5% - 5% U-235. The enrichment process separates gaseous UF6 into two streams, one being enriched to the required level and known as low-enriched uranium; the other is progressively depleted in U-235 and is called ‘tails’, or depleted uranium. The two enrichment processes in large scale commercial use are diffusion and centrifuge.
Enriched UF6 is transported to a fuel fabrication plant where it is converted to uranium dioxide (UO2) powder and pressed into small pellets and sintered at high temperatures. The pellets are inserted into metal tubes to form fuel rods. The rods are sealed and assembled to form fuel assemblies for use in the core of the nuclear reactor.