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Bullets, Blast, Jets and Fragments
Published in Paul J. Hazell, Armour, 2023
Depleted uranium or ‘DU’ is uranium that has had some of its U-235 content removed and therefore is only weakly radioactive. Furthermore, most modern DU projectile materials are also alloyed with a small (0.75%) amount of titanium to improve strength and corrosion resistance.
The Range of Environmental and Social Concerns
Published in Karlheinz Spitz, John Trudinger, Mining and the Environment, 2019
Karlheinz Spitz, John Trudinger
As the naturally occurring element with the highest atomic number, uranium is 70% more dense than lead. This silver gray metal is weakly radio-active. Three isotopes occur: U234, U235 and U238, of which U238 is the most prevalent accounting for more than 99% of uranium. As for all radioactive metals, the metallic nature is of no concern for the end user -uranium is used as nuclear fuel to produce energy, and 20 kg of uranium produces as much energy as 400,000 kg of coal. U235, the fissile isotope used in nuclear reactions, must be enriched prior to use. Uranium is not particularly rare, being more abundant than tin, mercury or silver. Several types of uranium ore occur; the predominant uranium mineral is uraninite. Uranium is chemically reactive and oxidizes readily. It may accumulate in the bones; its toxicity is of more concern than its radioactivity. Depleted uranium, U238, is used for armaments and other applications requiring a highly dense material.
Nuclear Resources
Published in D. Yogi Goswami, Frank Kreith, Energy Conversion, 2017
If the uranium is to be enriched to 4% U235, then 1 kg of 4% U235 product will require 7.4 kg of natural uranium feed and will produce 6.4 kg of waste uranium (tails or depleted uranium) with a U235 isotope content of 0.2%. This material is treated as a radioactive waste. Large quantities of tails (depleted uranium) exist as UF6 in their original shipping containers at the enriching plants. Depleted uranium (a dense material) has been used as shields for radioactive sources, armor piercing shells, balancing of helicopter rotor tips, yacht hold ballast, and balancing of passenger aircraft.
Uranium oxide catalysts: environmental applications for treatment of chlorinated organic waste from nuclear industry
Published in Environmental Technology, 2019
Svetlana Lazareva, Zinfer Ismagilov, Vadim Kuznetsov, Nadezhda Shikina, Mikhail Kerzhentsev
Compounds of depleted uranium can be employed as inexpensive and accessible materials (after the creation of the necessary infrastructure) in the development of efficient catalysts for various processes. Certainly, special attention should be paid to safety because of radioactivity and chemical toxicity of depleted uranium. Depleted uranium is weakly radioactive. Its radioactivity is determined mainly by alpha decay of U-238 isotope, with the radioactive half-life being about 4.5 billion years. External irradiation from depleted uranium is not a serious problem because alpha particles emitted by isotopes pass only several centimeters in air and can be stopped even by a sheet of paper. So they are unable to penetrate even into the superficial keratin layer of human skin [39,40]. The main radiation and toxic hazards of depleted uranium are related to its penetration as a dust into the body. Chemical toxicity of depleted uranium is less or comparable to that of transition metal compounds. As an example, the maximum permitted concentration limit of uranium in water is 0.075 mg/L, whereas the permitted limits of chromium, manganese and zinc are 0.26, 0.05 and 15 mg/L, respectively [41].
Surveillance results and bone effects in the Gulf War depleted uranium-exposed cohort
Published in Journal of Toxicology and Environmental Health, Part A, 2018
Melissa A McDiarmid, Marianne Cloeren, Joanna M Gaitens, Stella Hines, Elizabeth Streeten, Richard J. Breyer, Clayton H. Brown, Marian Condon, Tracy Roth, Marc Oliver, Lawrence Brown, Moira Dux, Michael R. Lewin-Smith, Frederick Strathmann, Maria A. Velez-Quinones, Patricia Gucer
For more than 25 years, the U.S. Department of Veterans Affairs (VA) has provided medical surveillance and clinical care for a group of Gulf War I Veterans who were tank crew members injured in combat incidents involving depleted uranium (DU) penetrator fire (Office of the Special Assistant for Gulf War Illnesses 2000). Depleted uranium (DU) is a by-product of the uranium enrichment process which possesses approximately 60% of the radioactivity of natural uranium. Because of its density, DU was incorporated into projectiles and armor by the military with its first combat use in the 1991 Gulf War. This cohort’s exposure to DU occurred via three routes: (1) inhalation of particulate aerosol with deposition in the lung at the time of penetrator impact, (2) superficial wound contamination with DU particulate and (3) longer-term DU absorption from fragments embedded in soft tissue (Parkhurst and others 2005; Squibb and McDiarmid 2006). The VA surveillance effort was tasked with assessing the adverse health effects (if any) of exposure to DU and determine the medical management of these wounded veterans.
Development of a treatment process and immobilization method for the volume reduction of uranium-bearing spent catalysts for final disposal
Published in Journal of Nuclear Science and Technology, 2018
Kwang-Wook Kim, Min-Jeong Kim, Maeng-Kyo Oh, Jimin Kim, Hyun-Hee Sung, Richard I. Foster, Keun-Young Lee
Uranium catalyst wastes are usually stored at the site where they had been used while awaiting a management strategy before final disposal [1,3]. Depleted uranium is classified as low-level radioactive waste [9]. Although the disposal route of radioactive waste varies depending on different circumstances within each country, its volume and associated disposal costs are anticipated to gradually increase over time, as the management of radioactive waste becomes severe in many countries [10–12]. It is not thought economical to recycle the depleted uranium component of the spent catalysts. Therefore, it is desirable to minimize the volume of these uranium-bearing wastes prior to disposal as much as possible.