Values in Spent Fuel From Power Reactors

Projection of needs for gamma radiation sources and other radioisotopes and assessment of alternatives for providing radiation sources

“…The prices of the rare gases krypton and xenon as commercially obtained from liquid air processes are about $0.65 per liter (STP) for krypton and B .10 about $4.00 per liter for xenon, each for orders of one thousand liters or more. An Exxon study (Rohrmann 1968) indicated that, if obtained from spent fuel, the selling price for krypton (including all the 85Kr) would be about $31.00 per liter but only about $0.42 per liter for xenon. The reason for this great difference relates to the fact that krypton removal during fuel processing is required to isolate the radioactive 85Kr and that essentially all the costs are thus borne by the need for the krypton processing.…”

“…The 90sr content is further reduced by the natural decay process; thus, in time the product can become so dilute that too little heat is produced to be usable in most applications. Existing designs for power-generation equipment require a minimum 9Dsr/Sr ratio of 0.4 or greater at the start of life, but some thermal applications may use material with a ratio of 0.3 under special conditions (International Study 1966-67;Rohrmann 1968Rohrmann , 1971; 'Characteristics of Radioisotopic Heat Sources" 1973).…”

“…Krypton-85 has a half-life of 10.72 years and decays to stable 85Rb by emission of betas having a maximum energy of 0.687 MeV accompanied by a low yield (0.41%} gamma having an energy of 0.514 MeV. The heat produced by 85Kr decay is 0.623 Wt (watts thermal} per gram, and the specific activity is 392 curies per gram (Chart of the Nuclides 1977;Rohrmann 1968;and Rohrmann 1971). Thus 85Kr is a useful heat source, its beta energy can be used to produce light, and the gamma activity can be used in nondestructive testing applications (International Study of Terrestrial Applications of Radioisotopic Power Sources 1966Sources -1967Eggers and Gaurthrop 1975;and Rohrmann 1974).…”

“…Fission-product krypton has a yield of 27 grams of 85Kr per tonne of fuel when discharged from the reactor and consists of about 7% 85Kr (Table B.2} (Rohrmann 1974;Chart of the Nuclides 1977;Rohrmann 1968). recover reactor produced krypton in as concentrated a form as possible and separate the isotopes as cleanly as possible by advanced isotope separation processes in the future.…”

Waste Management Program. Technical progress report, Aporil-June 1983

“…(1) specify process equipment, (2) install and test the process equipment at TNX, and (3) to relocate the process equipment to the beta-gamma incinerator site in H Area.…”