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(12) United States Patent (10) Patent No.: US 8,502,179 B1 Zolli (45) Date of Patent: Aug

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(12) United States Patent (10) Patent No.: US 8,502,179 B1 Zolli (45) Date of Patent: Aug US008502179B1 (12) United States Patent (10) Patent No.: US 8,502,179 B1 Zolli (45) Date of Patent: Aug. 6, 2013 (54) AMAL.GAM OF CRUSHED HAZARDOUS (56) References Cited RADIOACTIVE WASTE, SUCH AS SPENT NUCLEARFUEL RODS, MIXED WITH U.S. PATENT DOCUMENTS COPIOUSAMOUNTS OF LEAD PELLETS, 3,696,636 A 10, 1972 Mille ALSO GRANULATED, TO FORMA MIXTURE 4,102,512 A 7/1978 Lewallyn N.WHICH LEAD GRANULES OVERWHELM 4.338,215 A * 7/1982 Shaffer et al. ................... 588, 15 5,278,879 A 1/1994 McDaniels, Jr. 5,711,016 A * 1/1998 Carpena et al. ................. 588.10 (76) Inventor: Christine Lydie Zolli, Oldwick, NJ (US) 2002/O122525 A1 9/2002 Rosenberger 2006/0233685 A1 * 10, 2006 Janes ................................ 423.3 (*) Notice: Subject to any disclaimer, the term of this 2009/0205363 A1* 8, 2009 de Strulle ........................ 62/533 patent is extended or adjusted under 35 * cited by examiner U.S.C. 154(b) by 175 days. Primary Examiner — Robert Kim (74) Attorney, Agent, or Firm — Hess Patent Law Firm LLC; (21) Appl. No.: 13/173,205 Robert J. Hess (22) Filed: Jun. 30, 2011 (57) ABSTRACT A method, a product and an apparatus Suited to transform (51) Int. C. radioactive waste by forming an amalgam of crushed hazard G2 IF 3/00 (2006.01) ous radioactive waste, such as spent nuclear fuel rods, mixed G2 IF L/12 (2006.01) with copious amounts of lead pellets, also granulated, to form U.S. C. a mixture in which lead granules overwhelm, and which is (52) then further enclosed between solid lead slabs and com USPC ................... 250/517.1; 250/515.1; 250/505.1 pressed between rollers under high pressure to render the (58) Field of Classification Search USPC .......... 250/505.1, 506.1, 515.1, 516.1, 517.1, rolled end product a compacted amalgam radiation-free for 250/518.1, 519.1 integration into the environment. See application file for complete search history. 32 Claims, 4 Drawing Sheets Radioactive waste Spent fuel rods Lead pellets YES w w Spent Cryogenic Fluid fuel pool cooling chamber V-Y- BREAKNG JP DEVICES CRUSHERS GRENDING MACHINES gyratory jaw roll autogenous rod ball grinding grinder grinder mill nil mill MIXERS Lead sheets Static Hictical Drim inline w ROL BENDERS TO CO. INTO CYLINDERS COMPACTORSTO FORMCUBES Baling press U.S. Patent Aug. 6, 2013 Sheet 1 of 4 US 8,502,179 B1 Radioactive waste Spent fuel rods Lead pellets Spent Cryogenic Fluid fuel pool cooling chamber NO BREAKING UP DEVICES CRUSHERS GRENDING MACHINES gyratory jaw ro autogenous rod ball grinding grinder grinder mill mill mill MIXERS Static Helical Drum Inline ROLL BENDERS TO COIL NTO CYL INDERS COMPACTORS TO FORM CUBES Baling press FIG. 1 U.S. Patent Aug. 6, 2013 Sheet 2 of 4 US 8,502,179 B1 HERMETICALLY SEALED ROOM Vacuum CUTTERS, CRUSHERS, GRENDERS ROTARY KILNS, ROLLING MILL ROLL BENDERS COMPACTORS Conveyor FIG. 2 U.S. Patent Aug. 6, 2013 Sheet 3 of 4 US 8,502,179 B1 FIG. 3 U.S. Patent Aug. 6, 2013 Sheet 4 of 4 US 8,502,179 B1 US 8,502,179 B1 1. 2 AMAL.GAM OF CRUSHED HAZARDOUS facilities containing radioactive sources for industrial RADIOACTIVE WASTE, SUCH AS SPENT applications are in operation. NUCLEARFUEL RODS, MIXED WITH If spent nuclear fuel is to be reprocessed, the fuel elements COPIOUS AMOUNTS OF LEAD PELLETS, and fuel rods are chopped into pieces, the pieces are ALSO GRANULATED, TO FORMA MIXTURE chemically dissolved, and the resulting solution is sepa N.WHICH LEAD GRANULES OVERWHELM rated into uranium, plutonium, high level waste (HLW), and various other process wastes. FIELD OF THE INVENTION According to Dr. Frank Settle, "Nuclear Chemistry Recy cling Spent Reactor Fuel, published online by Chemcas The present invention relates to an amalgam of crushed 10 es.com at http://www.chemcases.com/nuclear/nc-13.html radioactive waste materials, such as crushed spent fuel rods Three options are available for cooled spent fuel rods; they and other radioactive byproducts from nuclear reactors, and can remain at the sites from which they have been copious amounts of fine pellets of lead that together form a removed from service, be moved to a more permanent mixture in the amalgam. The mixture is compressed under site for storage or they can be reprocessed to remove the heavy pressure and then compacted and rolled between sheets 15 uranium and plutonium. In either case, these fuel rods of lead slabe that serve as a barrier against radiation penetra must cool in storage ponds near the reactor for several tion. The end product may be safely integrated into the envi months in order to reduce their short-lived radioactivity ronment for storage since the radiation is in effect neutralized and to allow them to dissipate their initial high thermal from the amalgam. If the spent fuel rods are too hot due to energy. Reprocessing involves chopping up the fuel rods their radioactivity, then they may cooled rapidly with a cryo and dissolving the pieces. The plutonium and uranium genic fluid and, before they can become hot again, the spent are then removed and chemically separated. The fuel rods are crushed into Smaller pieces and dispersed to mix byproducts of reprocessing, transuranic elements and with the copious amounts of fine pellets of lead to form the fission products can be encapsulated in glass and dis mixture in the amalgam. posed as waste. 25 The online encyclopedia Widipedia mentions the follow BACKGROUND OF THE INVENTION ing nuclear waste techniques: Vitrification, Ion Exchange, Synroc. Molecules of lead trap uranium radiation, essentially Vitrification: Long-term storage of radioactive waste blocking radiation from appreciably penetrating the lead. requires the stabilization of the waste into a form which That lead traps radioactivity is well known conventionally. 30 will neither react nor degrade for extended periods of U.S. federal safety standards set forth regulations governing time. One way to do this is through vitrification. M. I. nuclear medicine and radiology departments of hospitals. For Ojovan, W. E. Lee. An Introduction to Nuclear Waste instance, the transport of nuclear medicine to and from a Immobilisation, Elsevier, Amsterdam, 315 pp. (2005). radiology departmentata hospital may be in a lead pig whose Currently at Sellafield (a nuclear processing site close to dimension and construction must meet federal safety require 35 the village of Seascale on the cost of the Irish Sea in ments to prevent unacceptable levels of radiation exposure to Cumbria, England), the high-level waste (PUREX (plu handlers of the lead pig. Personnel in radiology departments tonium uranium extraction based on liquid-liquid wear lead aprons to protect themselves from excessive expo extraction ion-exchange) first cycle raffinate (a liquid Sure to radiation in their working environment. Lead walls are stream that remains after the extraction with the immis provided to isolate cobalt cancer treatment machines and 40 cible liquid to remove Soutes from the original liquor)) is diagnostic X-ray machines. Therefore, lead has proven to be mixed with Sugar and then calcined. Calcination an effective barrier against radiation exposure to prevent the involves passing the waste through a heated, rotating penetration of the radiation through the lead. tube. The purposes of calcination are to evaporate the According to the International Atomic Energy Agency water from the waste, and de-nitrate the fission products (IAEA): 45 to assist the stability of the glass produced. National Radioactive sources are used throughout the world for a Research Council (1996). Nuclear Wastes: Technolo wide variety of peaceful and productive purposes in gies for Separation and Transmutation. Washington industry, medicine, research and education, and in mili D.C.: National Academy Press. tary applications. These sources utilize radioactive The calcine generated is fed continuously into an induc materials that are firmly contained or bound within a 50 tion heated furnace with fragmented glass. "Laboratory Suitable capsule or housing; although some sources scale vitrification and leaching of high-level waste for involve radioactive materials in an unsealed form. the purpose of simulant and glass and glass property Until the 1950s, only radionuclides of natural origin, par models validation. Retrieved 2009 Jul. 7. ticularly radium-226, were generally available for The resulting glass is a new Substance in which the waste Sources. Since then, radionuclides produced artificially 55 products are bonded into the glass matrix when it solidi in nuclear facilities and accelerators have become fies. This product, as a melt, is poured into stainless steel widely available, including cobalt-60, strontium-90, cylindrical containers ('cylinders’) in a batch process. caesium-137 and iridium-192. When cooled, the fluid solidifies (“vitrifies”) into the The present inventor notes that uranium 235 should be glass. Such glass, after being formed, is highly resistant mentioned. 60 to water. Ojovanm M. I. et al. (2006). “Corrosion of Millions of radioactive sources have been distributed nuclear waste glasses in non-saturated conditions: Time worldwide over the past 50 years, with hundreds of Temperature behaviour' (PDF). Retrieved 2008 Jun. 30. thousands currently being used, stored, and produced. After filling a cylinder, a seal is welded onto the cylinder. Worldwide, the IAEA has reported on specific applica The cylinder is then washed. After being inspected for tions: more than 10,000 radiotherapy units for medical 65 external contamination, the Steel cylinder is stored, usu care are in use; about 12,000 industrial sources for radi ally in an underground repository. In this form, the waste ography are Supplied annually; and about 300 irradiator products are expected to be immobilized for a long US 8,502,179 B1 3 4 period of time (many thousands of years).
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