Reprocessing plants

If the spent fuel is processed in a nuclear fuel reprocessing plant, the radioactive iodine species (elemental iodine and methyl iodide) trapped in the spent fuel elements ate ultimately released into dissolver off gases. The radioactive iodine may then be captured by chemisorption on molecular sieve 2eohtes containing silver (89). 

Hafnium neutron absorption capabilities have caused its alloys to be proposed as separator sheets to allow closer spacing of spent nuclear fuel rods in interim holding ponds. Hafnium is the preferred material of constmction for certain critical mass situations in spent fuel reprocessing plants where hafnium s excellent corrosion resistance to nitric acid is also important. 

Lead bricks are generahy used as temporary shields for radiation sources at nuclear power stations, research institutes, hospitals, and fuel reprocessing plants. Plat, rectangular bricks requite a double layer with staggered seams whereas the interlocking bricks requite only one course. Lead shot can be poured into inaccessible areas like a Hquid. 

As of 1995, there were no nuclear fuel reprocessing plants operating in the United States. Other nuclear nations have constmcted second- or third-generation reprocessing faciUties. These nations have signed the nuclear nonproliferation treaty, and the faciUties are under the purview of the International Atomic Energy Agency (IAEA). 

Safety analysis Report, NFS Reprocessing Plant, Docket-50-201, Nuclear Euel Services, Inc., Rockville, Md., 1973. 

D. W. HoWid.2cy, A Eiterature Survey Methodsfor the Removal of Iodine Spedafrom Off-Gas andEiquid Waste Streams of Nuclear Power and Nuclear Fuel Reprocessing Plants, with Emphasis on Solid Sorbents, ORNL/TM-6350, Oak Ridge National Laboratory, Oak Ridge, Term., 1979. 

One feature of reprocessing plants which poses potential risks of a different nature from those ia a power plant is the need to handle highly radioactive and fissionable material ia Hquid form. This is necessary to carry out the chemical separations process. The Hquid materials and the equipment with which it comes ia contact need to be surrounded by 1.5—1.8-m thick high density concrete shielding and enclosures to protect the workers both from direct radiation exposure and from inhalation of airborne radioisotopes. Rigid controls must also be provided to assure that an iaadvertent criticahty does not occur. 

In plutonium-fueled breeder power reactors, more plutonium is produced than is consumed (see Nuclearreactors, reactor types). Thus the utilisa tion of plutonium as a nuclear energy or weapon source is especially attractive to countries that do not have uranium-enrichment faciUties. The cost of a chemical reprocessing plant for plutonium production is much less than that of a uranium-235 enrichment plant (see Uranium and uranium compounds). Since the end of the Cold War, the potential surplus of Pu metal recovered from the dismantling of nuclear weapons has presented a large risk from a security standpoint. 

Thermal oxide reprocessing plant, 6, 885 Thermal reactor fuels, 6,926 dissolution, 6,927 irradiated... 

A second source of plutonium, dispersed more locally, is liquid effluent from fuel reprocessing facilities. One such is the fuel reprocessing plant at Windscale, Cumbria in the United Kingdom where liquid waste is released to the Irish Sea(6). Chemical analysis of this effluent shows that about one percent or less of the plutonium is in an oxidized form before it contacts the marine water(7). Approximately 95 percent of the plutonium rapidly adsorbs to particulate matter after discharge and deposits on the seabed while 5 percent is removed from the area as a soluble component ). Because this source provided concentrations that were readily detected, pioneering field research into plutonium oxidation states in the marine environment was conducted at this location. 

Similar demands for reference materials also arise in connection with the monitoring of radioactivity in and around nuclear installations (nuclear power plants, nuclear fuel and reprocessing plants, and nuclear waste facilities). These, in fact, are now the main applications of radionuclide reference materials. 

Carlinford, Ireland (port city), impact from Sellafield Reprocessing Plant, 1991-1997 Ryanetal. 1999... 

Irish Sea, site impacted by Windscale Reprocessing Plant and reference sites, 1977 EPA 1984... 

Environmental Fate. The environmental fate of americium has been extensively studied in relation to its introduction into the Irish Sea from the BNFL nuclear fuel reprocessing plant at Sellafield, United Kingdom (Belot et al. 1982 Bennett 1976 Bunzl et al. 1994, 1995 Malcolm et al. 1990 McCartney et al. 1994 McKay et al. 1994a Murray et al. 1978, 1979 Pattenden and McKay 1994 Walker et al. 1986). 

Facilities were built for receipt and storage of spent fuel, clearance was obtained from major ports for its import, negotiations were carried out with nuclear utility operators and suppliers for its acceptance by the AEC, and research and development was carried out to permit reprocessing in H-canyon, the most successful and versatile reprocessing plant at SRP. 

The Multi-Purpose Processing Facility was installed in F Canyon (reprocessing plant) at SRP for separation of Californium and trans-californium elements using newly developed, high-pressure, chromatographic cation exchange processes. 

Perhaps there should be centralized areas for storage of spent fuel from present reactor types. These storage areas should be adjacent to reprocessing plants which would be built to process the spent fuel to provide the new fuel for the Fast Reactors going on line. 

The fast reactor high level waste is accumulated at the reprocessing plants and retains its toxicity for only a few hundred years, rather than the tens of thousands of years ofthe spent fuel wastes from our present reactors,. Thus, the nuclear waste disposal problems are minimal and arrangements for disposal could be made on a global basis. 

Because the concentration of "Tc in sea water is usually very low, there have been only limited reliable data, except for those cases in which the "Tc concentration is relatively high due to the release of nuclear waste from spent fuel reprocessing plants. However, the advent of highly sensitive detection by ICP-MS has changed this situation. 

Fig. 8. Variation with location of the mean levels of "Tc in samples of Fucus serrantus bioindicators along the French coast of the English Channel. The discharge outlet at the La Hague reprocessing plant is shown by an arrow. (Reprinted with permission from Ref. 43. Copyright (1987) Elsevier Science Ltd)...

Goldberg [44], surprisingly high concentrations were detected for the former 16, 000 Bq/kg, for the latter 43,000-46,000 Bq/kg. All these data indicate that technetium should be carefully recovered in reprocessing plants. The systematic recovery of technetium together with elements of the platinum group from high level wastes have been discussed by Kubota [45],... 

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