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Resin-based preparation of HTGR fuels: operation of an engineering-scale uranium loading system

Description: The fuel particles for recycle of /sup 233/U to High-Temperature Gas-Cooled Reactors are prepared from uranium-loaded carboxylic acid ion exchange resins which are subsequently carbonized, converted, and refabricated. The development and operation of individual items of equipment and of an integrated system are described for the resin-loading part of the process. This engineering-scale system was full scale with respect to a hot demonstration facility, but was operated with natural uranium. The… more
Date: October 1, 1977
Creator: Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AQUEOUS HOMOGENEOUS REACTOR FUEL PROCESSING--THE BEHAVIOR OF INSOLUBLE CORROSION AND FISSION PRODUCTS

Description: For presentation at the American Chemical Society's Nuclear Technology Symposium, Boston, Apr. 5-10, Information is presented from studies with materials and conditions simulating those expected in anm aqueous homogeneous reactor for the formation of insoluble corrosion and fission products in aqueous UO/sub 2/ SO/sub 4/ solutions used as a reactor fuel. Sulfate salts which become insoluble as the temperature inereases deposited preferentially and reversibly on hot walls. Oxides from hydrolysis… more
Date: May 31, 1958
Creator: Haas, P.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resin-based preparation of HTGR fuels: uranium loading development studies

Description: Uranium leading flowsheet conditions for recycle $sup 233$U were investigated and demonstrated in engineering equipment. Calculations made to estimate the capacities of equipment which is geometrically safe with respect to control of nuclear criticality indicate 100 kg/day or more of uranium for a single nitrate extraction line with four batch loading contactors. The four batch contactors might be replaced by a single continuous resin loading contactor of a modified Higgins contactor design. Th… more
Date: January 1, 1975
Creator: Haas, P.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solids Separation by a Hydraulic Cyclone With a Batch Underflow Receiver

Description: >Engineering correlations based on experimental studies are presented for the application of batch accumulation of solids separated from solid-liquid feed to a cyclone. This method of cyclone operation simplifies the problem of flow control involved with continuous underflow. The efficiency and capacity correlations for hydroclones with continuous underflow also apply to this type of operation. The volume flow exchanged with the underflow receiver may be varied from 0.2 to 6% of the feed flo… more
Date: March 18, 1960
Creator: Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preparation of thorium-uranium gel spheres

Description: Ceramic oxide spheres with diameters of 15 to 1500 ..mu..m are being evaluated for fabrication of power reactor fuel rods. (Th,U)O/sub 2/ spheres can be prepared by internal or external chemical gelation of nitrate solutions or oxide sols. Two established external gelation techniques were tested but proved to be unsatisfactory for the intended application. Established internal gelation techniques for UO/sub 2/ spheres were applied with minor modifications to make 75% ThO/sub 2/-25% UO/sub 2/ sp… more
Date: January 1, 1980
Creator: Spence, R.D. & Haas, P.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Partial thermal denitration of uranyl nitrate solutions in a screw denitrator

Description: Weak-acid ion exchange resin is loaded with uranium by acid-deficient uranyl nitrate solutions that have a nitrate uranium ratio of about 1.6. Processing this solution from an acid-excess uranyl nitrate solution by thermal denitration in a screw denitrator is described. Direct processing of this solution resulted in an insufficient acid deficiency of about C/sub N//C/sub U/ = 1.8. Therefore, the process was modified; a highly denitrated UO/sub 3/ slid was processed with C/sub N//C/sub U/ = 0.2,… more
Date: August 1, 1978
Creator: Ringel, H.D. & Haas, P.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design and test of a thermosiphon evaporator for acid-deficient uranyl nitrate

Description: The reference process to recycle /sup 233/U to HTGRs begins with the receipt of the /sup 233/UO/sub 2/(NO/sub 3/)/sub 2/ product solution from a reprocessing plant, which is fed to a resin loading system. The nitrate is removed by extraction with a liquid organic amine. By adding an evaporator to remove water, a continuous, high-efficiency process for loading uranium on ion exchange resin is possible. A vertical thermosiphon evaporator was designed, fabricated, and tested with natural uranium t… more
Date: November 1, 1976
Creator: Drago, J. P. & Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Drying of uranium-loaded cation exchange resin with microwave heating

Description: The reference fuel kernel for recycle of /sup 233/U to HTGRs (High-Temperature Gas-Cooled Reactors) is prepared by loading carboxylic acid cation exchange resin with uranium and carbonizing it at controlled conditions. The wet, uranium-loaded resin must be dried to a water content of 10 to 16 wt percent prior to carbonization to minimize handling problems. Microwave heating was demonstrated to give controlled and reproducible dried resin in a vessel whose dimensions were safe for nuclear critic… more
Date: December 1, 1976
Creator: Drago, J. P. & Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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HRP-CPP: Dissolution of Zirconium and stainless steel corrosion product oxides

Description: Dissolution methods were developed to permit representative sampling of the slurry of corrosion and fission products collected by the HRT chemical process-ing plant. The procedure selected for HRT-CPP application was to use 15 ml of 10.8 M H/sub 2/SO/sub 4/ per gram of solids with agitation by boiling in a tantalum-lined dissolver. (auth)
Date: August 1, 1958
Creator: Snider, J. W. & Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improved size uniformity of sol-gel spheres by imposing a vibration on the sol in dispersion nozzles

Description: A major part of the Th-- /sup 233/U fuel cycle program at ORNL has been concerned with the development of sol-gel processes to prepare ThO/sub 2/ and ThO/ sub 2/--/sup 233/UO/sub 2/ spheres. The formation of sol drops having a uniform and controlled diameter is important to any sol-gel process for preparing oxide kernels for High Temperature Gas-Cooled Reactor fuels. A recently developed technique that incorporates use of a sol disperser with vibration has met the dispersion requirements for OR… more
Date: May 1, 1973
Creator: Haas, P. A. & Lackey, W. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Method for producing nuclear fuel

Description: Nuclear fuel is made by contacting an aqueous solution containing an actinide salt with an aqueous solution containing ammonium hydroxide, ammonium oxalate, or oxalic acid in an amount that will react with a fraction of the actinide salt to form a precipitate consisting of the hydroxide or oxalate of the actinide. A slurry consisting of the precipitate and solution containing the unreacted actinide salt is formed into drops which are gelled, calcined, and pressed to form pellets.
Date: April 24, 1981
Creator: Haas, P.A.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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Literature information applicable to the reaction of uranium oxides with chlorine to prepare uranium tetrachloride

Description: The reaction of uranium oxides and chlorine to prepare anhydrous uranium tetrachloride (UCl{sub 4}) are important to more economical preparation of uranium metal. The most practical reactions require carbon or carbon monoxide (CO) to give CO or carbon dioxide (CO{sub 2}) as waste gases. The chemistry of U-O-Cl compounds is very complex with valances of 3, 4, 5, and 6 and with stable oxychlorides. Literature was reviewed to collect thermochemical data, phase equilibrium information, and results … more
Date: February 1, 1992
Creator: Haas, P.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Literature information applicable to the reaction of uranium oxides with chlorine to prepare uranium tetrachloride

Description: The reaction of uranium oxides and chlorine to prepare anhydrous uranium tetrachloride (UCl{sub 4}) are important to more economical preparation of uranium metal. The most practical reactions require carbon or carbon monoxide (CO) to give CO or carbon dioxide (CO{sub 2}) as waste gases. The chemistry of U-O-Cl compounds is very complex with valances of 3, 4, 5, and 6 and with stable oxychlorides. Literature was reviewed to collect thermochemical data, phase equilibrium information, and results … more
Date: February 1, 1992
Creator: Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Catalyzed reduction of nitrate in aqueous solutions

Description: Sodium nitrate and other nitrate salts in wastes is a major source of difficulty for permanent disposal. Reduction of nitrate using aluminum metal has been demonstrated, but NH{sub 3}, hydrazine, or organic compounds containing oxygen would be advantageous for reduction of nitrate in sodium nitrate solutions. Objective of this seed money study was to determine minimum conditions for reduction. Proposed procedure was batchwise heating of aqueous solutions in closed vessels with monitoring of tem… more
Date: August 1, 1994
Creator: Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reaction of formaldehyde and nitric acid in a remotely operated thermosiphon evaporator

Description: Conditions have been developed for the safe and successful use of a method for reacting formaldehyde with excess nitric acid, while simulataneously concentrating a fissile uranium nitrate solution. This process, which is being conducted in a remotely operated thermosiphon evaporator, has been adapted to plant scale and is being used to process multikilogram batches.
Date: January 1, 1985
Creator: Hall, R.; Patton, B.D. & Haas, P.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reaction of formaldehyde and nitric acid in a remotely operated thermosiphon evaporator

Description: A safe, controlled method for reacting formaldehyde with excess nitric acid, while simultaneously concentrating a fissile uranium nitrate solution, was developed and is being used successfully at Oak Ridge National Laboratory in a remotely operated thermosiphon evaporator. The operation was adapted from laboratory studies to semicontinuously process multikilogram batches. Thus far, experience with this system includes the successful processing of more than 260 batches (2.7 kg per batch) of solu… more
Date: January 1, 1986
Creator: Hall, R.; Patton, B.D. & Haas, P.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of the thermal denitration in-storage-can step in the CEUSP process

Description: A thermal denitration in-the-storage-can process has been developed for use in the Consolidated Edison Uranium Solidification Program Facility. This process is being used to convert approx.1000 kg of highly fissile and radioactive uranium to a solid form for safe long-term storage. The material being solidified also contains approx.300 kg of cadmium and approx.40 kg of gadolinium which had been combined with the uranium to provide criticality safety. The unique thermal denitration process was f… more
Date: January 1, 1986
Creator: Vedder, R.J.; Collins, E.D. & Haas, P.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sphere-cal process: fabrication of fuel pellets from gel microspheres

Description: The sphere-cal process uses gel-derived microspheres as feed material for fuel pellet fabrication. The basic sphere-cal process consists of microsphere gelation, drying, and calcining followed by pellet pressing and sintering. Each of these process steps were studied to try to determine the important parameters for the production of high quality UO/sub 2/, ThO/sub 2/, and (Th,U)O/sub 2/ fuel pellets. UO/sub 2/ sintered pellet densities increase both with decreasing calcination temperature (1000… more
Date: September 1, 1979
Creator: Tiegs, S.M.; Haas, P.A. & Spence, R.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Drying of ion-exchange resins for resin-based preparation of nuclear reactor fuels

Description: The reference fuel kernel for recycle of /sup 233/U to HTGRs (High Temperature Gas-Cooled Reactors) is prepared by loading carboxylic acid cation-exchange resins with uranium and carbonizing at controlled conditions. The loaded, dried resin must meet specifications for sphericity, composition, and other properties. Microwave heating is used to give controlled and reproducible drying of 11-liter batches of uranium-loaded (4 kg of uranium) resin in a vessel of safe dimensions for nuclear critical… more
Date: January 1, 1976
Creator: Drago, J. P.; Haas, P. A. & Million, D. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tests of a Higgins contactor for the engineering-scale resin loading of uranium

Description: The loading of uranium on weak-acid ion exchange resin is a basic step in the production of fuel particles for high-temperature gas-cooled reactors (HTGRs). In the work reported here, an engineering-scale continuous resin loader (2-in.-ID Higgins contactor) was tested with existing engineering-scale process equipment. The Higgins contactor was first successfully used to convert Na/sup +/-form resin to the H/sup +/-form; then it was evaluated as a uranium loader. Results show that the 2-in.-ID H… more
Date: January 1, 1978
Creator: Spence, R. D. & Haas, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical flowsheet conditions for preparing urania spheres by internal gelation

Description: Small, ceramic urania spheres can be prepared for use as nuclear fuel by internal chemical gelation of uranyl nitrate solution droplets. Decomposition of hexamethylenetetramine (HMTA) dissolved in the uranyl nitrate solution releases ammonia to precipitate hydrated UO/sub 3/. Previously established flowsheet conditions have been improved and modified at ORNL and have been applied to prepare dense UO/sub 2/ spheres with average diameters of 1200, 300, and 30 ..mu..m. Acid-deficient uranyl nitrat… more
Date: January 1, 1979
Creator: Haas, P.A.; Begovich, J.M.; Ryon, A.D. & Vavruska, J.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Chemical flowsheet conditions for preparing urania spheres by internal gelation

Description: Small, ceramic urania spheres can be prepared for use as nuclear fuel by internal chemical gelation of uranyl nitrate solution droplets. Decomposition of hexamethylenetetramine (HMTA) dissolved in the uranyl nitrate solution releases ammonia to precipitate hydrated UO/sub 3/. Previously established flowsheet conditions have been improved and modified at ORNL and have been applied to prepare dense UO/sub 2/ spheres with average diameters of 1200, 300, and 30 ..mu..m.
Date: July 1, 1979
Creator: Haas, P.A.; Begovich, J.M.; Ryon, A.D. & Vavruska, J.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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