Waste formed by vitrification of liquid high-level waste.
The Hanford site represents 7-9 percent of America's high-level radioactive waste by volume. Nuclear reactors line the riverbank at the Hanford Site along the Columbia River in January 1960.
Liquid high-level waste is typically held temporarily in underground tanks pending vitrification. Most of the high-level waste created by the Manhattan Project and the weapons programs of the cold war exists in this form because funding for further processing was typically not part of the original weapons programs. Both spent nuclear fuel and vitrified waste are considered [2] as suitable forms for long term disposal, after a period of temporary storage in the case of spent nuclear fuel.
HLW contains many of the fission products and transuranic elements generated in the reactor core and is the type of nuclear waste with the highest activity. HLW accounts for over 95% of the total radioactivity produced in the nuclear power process. In other words, while most nuclear waste is low-level and intermediate-level waste, such as protective clothing and equipment that have been contaminated with radiation, the majority of the radioactivity produced from the nuclear power generation process comes from high-level waste.
Some countries, particularly France, reprocess commercial spent fuel.
High-level waste is very radioactive and, therefore, requires special shielding during handling and transport. Initially it also needs cooling, because it generates a great deal of heat. Most of the heat, at least after short-lived nuclides have decayed, is from the medium-lived fission productscaesium-137 and strontium-90, which have half-lives on the order of 30 years.
A typical large 1000 MWe nuclear reactor produces 25–30 tons of spent fuel per year.[3] If the fuel were reprocessed and vitrified, the waste volume would be only about three cubic meters per year, but the decay heat would be almost the same.
High-level waste is the highly radioactive waste material resulting from the reprocessing of spent nuclear fuel, including liquid waste produced directly in reprocessing and any solid material derived from such liquid waste that contains fission products in sufficient concentrations; and other highly radioactive material that is determined, consistent with existing law, to require permanent isolation.[4]
Spent (used) reactor fuel.
Spent nuclear fuel is used reactor fuel that is no longer efficient in creating electricity, because its fission process has slowed due to a build-up of reaction poisons. However, it is still thermally hot, highly radioactive, and potentially harmful.
Waste materials from reprocessing.
Materials for nuclear weapons are acquired by reprocessing spent nuclear fuel from breeder reactors. Reprocessing is a method of chemically treating spent fuel to separate out uranium and plutonium. The byproduct of reprocessing is a highly radioactive sludge residue.
High-level radioactive waste is stored for 10 or 20 years in spent fuel pools, and then can be put in dry cask storage facilities.
In 1997, in the 20 countries which account for most of the world's nuclear power generation, spent fuel storage capacity at the reactors was 148,000 tonnes, with 59% of this utilized. Away-from-reactor storage capacity was 78,000 tonnes, with 44% utilized.[5]
^Dept of Energy - RADIOACTIVE WASTE MANAGEMENT MANUAL - DOE M 435.1-1
^. martinfrost.ws. Archived from the original on 3 December 2012. Retrieved 16 April 2013.
Referencesedit
Fentiman, Audeen W. and James H. Saling. Radioactive Waste Management. New York: Taylor & Francis, 2002. Second ed.
Large, John H. Risks and Hazards arising the Transportation of Irradiated Fuel and Nuclear Materials in the United Kingdom R3144-A1, March 2006
External linksedit
NRC Backgrounder on Radioactive Waste
May 18, 2024
high, level, waste, also, high, level, radioactive, waste, management, type, nuclear, waste, created, reprocessing, spent, nuclear, fuel, exists, main, forms, first, second, cycle, raffinate, other, waste, streams, created, nuclear, reprocessing, waste, formed. See also High level radioactive waste management High level waste HLW is a type of nuclear waste created by the reprocessing of spent nuclear fuel 1 It exists in two main forms First and second cycle raffinate and other waste streams created by nuclear reprocessing Waste formed by vitrification of liquid high level waste The Hanford site represents 7 9 percent of America s high level radioactive waste by volume Nuclear reactors line the riverbank at the Hanford Site along the Columbia River in January 1960 Liquid high level waste is typically held temporarily in underground tanks pending vitrification Most of the high level waste created by the Manhattan Project and the weapons programs of the cold war exists in this form because funding for further processing was typically not part of the original weapons programs Both spent nuclear fuel and vitrified waste are considered 2 as suitable forms for long term disposal after a period of temporary storage in the case of spent nuclear fuel HLW contains many of the fission products and transuranic elements generated in the reactor core and is the type of nuclear waste with the highest activity HLW accounts for over 95 of the total radioactivity produced in the nuclear power process In other words while most nuclear waste is low level and intermediate level waste such as protective clothing and equipment that have been contaminated with radiation the majority of the radioactivity produced from the nuclear power generation process comes from high level waste Some countries particularly France reprocess commercial spent fuel High level waste is very radioactive and therefore requires special shielding during handling and transport Initially it also needs cooling because it generates a great deal of heat Most of the heat at least after short lived nuclides have decayed is from the medium lived fission products caesium 137 and strontium 90 which have half lives on the order of 30 years A typical large 1000 MWe nuclear reactor produces 25 30 tons of spent fuel per year 3 If the fuel were reprocessed and vitrified the waste volume would be only about three cubic meters per year but the decay heat would be almost the same It is generally accepted that the final waste will be disposed of in a deep geological repository and many countries have developed plans for such a site including Finland France Japan United States and Sweden Contents 1 Definitions 2 Storage 3 See also 4 Notes 5 References 6 External linksDefinitions editLong lived fission productsvte Nuclide t1 2 Yield Q a 1 bg Ma a 2 keV 99Tc 0 211 6 1385 294 b 126Sn 0 230 0 1084 4050 a 3 bg 79Se 0 327 0 0447 151 b 135Cs 1 33 6 9110 a 4 269 b 93Zr 1 53 5 4575 91 bg 107Pd 6 5 1 2499 33 b 129I 15 7 0 8410 194 bg Decay energy is split among b neutrino and g if any Per 65 thermal neutron fissions of 235U and 35 of 239Pu Has decay energy 380 keV but its decay product 126Sb has decay energy 3 67 MeV Lower in thermal reactors because 135Xe its predecessor readily absorbs neutrons Medium lived fission products further explanation needed t year Yield Q keV bg 155Eu 4 76 0 0803 252 bg 85Kr 10 76 0 2180 687 bg 113mCd 14 1 0 0008 316 b 90Sr 28 9 4 505 2826 b 137Cs 30 23 6 337 1176 bg 121mSn 43 9 0 00005 390 bg 151Sm 88 8 0 5314 77 b High level waste is the highly radioactive waste material resulting from the reprocessing of spent nuclear fuel including liquid waste produced directly in reprocessing and any solid material derived from such liquid waste that contains fission products in sufficient concentrations and other highly radioactive material that is determined consistent with existing law to require permanent isolation 4 Spent used reactor fuel Spent nuclear fuel is used reactor fuel that is no longer efficient in creating electricity because its fission process has slowed due to a build up of reaction poisons However it is still thermally hot highly radioactive and potentially harmful Waste materials from reprocessing Materials for nuclear weapons are acquired by reprocessing spent nuclear fuel from breeder reactors Reprocessing is a method of chemically treating spent fuel to separate out uranium and plutonium The byproduct of reprocessing is a highly radioactive sludge residue Storage editMain article High level radioactive waste management nbsp Spent fuel pool High level radioactive waste is stored for 10 or 20 years in spent fuel pools and then can be put in dry cask storage facilities In 1997 in the 20 countries which account for most of the world s nuclear power generation spent fuel storage capacity at the reactors was 148 000 tonnes with 59 of this utilized Away from reactor storage capacity was 78 000 tonnes with 44 utilized 5 See also editRadioactive waste Low level waste Transuranic waste Mixed waste Into Eternity film Notes edit M I Ojovan and W E Lee An Introduction to Nuclear Waste Immobilisation Elsevier Amsterdam 2005 Radioactive Waste Management WNO radwaste management Dept of Energy RADIOACTIVE WASTE MANAGEMENT MANUAL DOE M 435 1 1 Radioactive waste martinfrost ws Archived from the original on 3 December 2012 Retrieved 16 April 2013 References editFentiman Audeen W and James H Saling Radioactive Waste Management New York Taylor amp Francis 2002 Second ed Large John H Risks and Hazards arising the Transportation of Irradiated Fuel and Nuclear Materials in the United Kingdom R3144 A1 March 2006 1 External links editNRC Backgrounder on Radioactive Waste Retrieved from https en wikipedia org w index php title High level waste amp oldid 1176910609, wikipedia, wiki, book, books, library,
