Uranium miningUranium mining is the process of extraction of uranium ore from the ground. Over 50 thousand tons of uranium were produced in 2019. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account for 68% of world production. Other countries producing more than 1,000 tons per year included Namibia, Niger, Russia, Uzbekistan, the United States, and China. Nearly all of the world's mined uranium is used to power nuclear power plants.
UraniumUranium is a chemical element with symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium radioactively decays by emitting an alpha particle. The half-life of this decay varies between 159,200 and 4.5 billion years for different isotopes, making them useful for dating the age of the Earth.
Enriched uraniumEnriched uranium is a type of uranium in which the percent composition of uranium-235 (written 235U) has been increased through the process of isotope separation. Naturally occurring uranium is composed of three major isotopes: uranium-238 (238U with 99.2739–99.2752% natural abundance), uranium-235 (235U, 0.7198–0.7202%), and uranium-234 (234U, 0.0050–0.0059%). 235U is the only nuclide existing in nature (in any appreciable amount) that is fissile with thermal neutrons.
Uranium oreUranium ore deposits are economically recoverable concentrations of uranium within the Earth's crust. Uranium is one of the most common elements in the Earth's crust, being 40 times more common than silver and 500 times more common than gold. It can be found almost everywhere in rock, soil, rivers, and oceans. The challenge for commercial uranium extraction is to find those areas where the concentrations are adequate to form an economically viable deposit. The primary use for uranium obtained from mining is in fuel for nuclear reactors.
Depleted uraniumDepleted uranium (DU; also referred to in the past as Q-metal, depletalloy or D-38) is uranium with a lower content of the fissile isotope than natural uranium. Natural uranium contains about , while the DU used by the U.S. Department of Defense contains or less. The less radioactive and non-fissile constitutes the main component of depleted uranium. Uses of DU take advantage of its very high density of , denser than lead.
Uranium marketThe uranium market, like all commodity markets, has a history of volatility, moving with the standard forces of supply and demand as well as geopolitical pressures. It has also evolved particularities of its own in response to the unique nature and use of uranium. Historically, uranium has been mined in countries willing to export, including Australia and Canada. However, countries now responsible for more than 50% of the world’s uranium production include Kazakhstan, Namibia, Niger, and Uzbekistan.
Uranium-238Uranium-238 (238U or U-238) is the most common isotope of uranium found in nature, with a relative abundance of 99%. Unlike uranium-235, it is non-fissile, which means it cannot sustain a chain reaction in a thermal-neutron reactor. However, it is fissionable by fast neutrons, and is fertile, meaning it can be transmuted to fissile plutonium-239. 238U cannot support a chain reaction because inelastic scattering reduces neutron energy below the range where fast fission of one or more next-generation nuclei is probable.
Reprocessed uraniumReprocessed uranium (RepU) is the uranium recovered from nuclear reprocessing, as done commercially in France, the UK and Japan and by nuclear weapons states' military plutonium production programs. This uranium makes up the bulk of the material separated during reprocessing. Commercial LWR spent nuclear fuel contains on average (excluding cladding) only four percent plutonium, minor actinides and fission products by weight.
Chemical elementA chemical element is a chemical substance that cannot be broken down into other substances. The basic particle that constitutes a chemical element is the atom, and each chemical element is distinguished by the number of protons in the nuclei of its atoms, known as its atomic number. For example, oxygen has an atomic number of 8, meaning that each oxygen atom has 8 protons in its nucleus. This is in contrast to chemical compounds and mixtures, which contain atoms with more than one atomic number.
BioremediationBioremediation broadly refers to any process wherein a biological system (typically bacteria, microalgae, fungi, and plants), living or dead, is employed for removing environmental pollutants from air, water, soil, flue gasses, industrial effluents etc., in natural or artificial settings. The natural ability of organisms to adsorb, accumulate, and degrade common and emerging pollutants has attracted the use of biological resources in treatment of contaminated environment.
