Gaseous diffusion enrichment process

To convert naturally occurring uranium oxide, yellow cake or U Og, to the gaseous UF, hydrofluoric acid is first used to convert the U Og to UF. Further fluorination using fluorine (generated from more HF) is employed to convert the UF to UF. The UF is then processed at gaseous diffusion enrichment plants. 

Although other technologies are now coming into use for this purpose, gaseous diffusion has played an important role in the enrichment of uranium for use in nuclear reactors. Natural uranium is mostly 2, which cannot be fissioned to prodnce energy. It contains only about 0.7% of the fissionable nuclide IfU. For uranium to be useful as a nuclear fuel, the relative amount of IfU must be increased to abont 3%. In the gas diffusion enrichment process, the natnral nraninm (containing IfU and a small amount of 9iU) reacts with fluorine to form a mixtnre of and UFg. Because these... 

The Silex fuel technology exclusively licensed to GE in 2006 was later licensed to Global Laser Enrichment (GLE) which is made up of GE, Hitachi, and Cameco. GLE now has an NRC license to construct and operate a laser enrichment plant in Wilmington, North Carolina. Also, GLE and DOE are currently negotiating a commercial contract to establish a uranium tails processing facility based on the Silex process at the closed down gaseous diffusion enrichment plant at Paducah, Kentucky. 

Uranium hexafluoride is used in the gaseous diffusion process for the separation and enrichment of uranium-235, which exists in low concentration in natural uranium. The enriched UF is converted back into an oxide and used as fuel for the nuclear power industry. 

The UFg is then isotopicaHy enriched by gaseous diffusion or gas centrifuge processes for nuclear appHcations. 

Natural uranium consists mostly of and 0.711 wt % plus an inconsequential amount of The United States was the first country to employ the gaseous diffusion process for the enrichment of the fissionable natural uranium isotope. During the 1940s and 1950s, this enrichment appHcation led to the investment of several bUHon dollars in process faciHties. The original plants were built in 1943—1945 in Oak Ridge, Teimessee, as part of the Manhattan Project of World War II. 

G. F. Mailing and E. Von H.a]le,Merocfnamic Isotope Separation Processes for Cranium Enrichment Process Requirement, paper presented at the Symposium on New Advances ia Isotope Separation, Div. of Nuclear Chemistry and Technology, American Chemical Society, San Francisco, Calif., Aug. 1976 CCC-ND Report K/OM-2872, Oak Ridge Gaseous Diffusion Plant, Oak Ridge, Term., Oct. 7, 1976. 

Enrichment, Isotopic—An isotopic separation process by which the relative abundances of the isotopes of a given element are altered, thus producing a form of the element that has been enriched in one or more isotopes and depleted in others. In uranium enrichment, the percentage of uranium-235 in natural uranium can be increased from 0.7% to >90% in a gaseous diffusion process based on the different thermal velocities of the constituents of natural uranium (234U, 235U, 238U) in the molecular form UF6. 

The gaseous diffusion method of isotope separation is based upon the difference in the rate of diffusion of gases that differ in density. Since the rate of diffusion of a gas is inversely proportionate to the square root of its density, die lighter of two gases will diffuse more rapidly than the heavier. Therefore, die result of a partial diffusion process will be an enrichment of the partial product in die lighter component. 

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