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Chemical Techinology Division, Unit Operations Section Monthly Progress Report, April 1960

Description: Experiments showed that 30% tributyl phosphate will not extract acid- deficient species of uranyl nitrate. Flooding throughputs for the Mark I stacked- clone contactor ranged from 600 cc/min organic at zero aqueous to 60 cc/min organic at 1950 cc aqueous. A large electronic vibrator of 5000-lb thrust was found somewhat inferior to pneumatic vibration for compacting oxide fuels into stainless-steel tubes. Tests were started on the use of fixed-bed CuO oxidizers for removing hydrogen contamination from helium gas streams. None of the variables studied within this period effected an increase in particle size in the denitration of thorium nitrate to produce ThO/sub 2/. The rate of uranyl sulfate loading on nitrate equilibrated Dowex 21K appears to be essentially independent of the loading solution sulfate concentration. The nitric acid concentrations corresponding to maximum UO/sub 2/-ThO/sub 2/ pellet dissolution rate were 15.5 M for Thorex solution and 13 M for the adjusted Darex solution. Two additional Semicontinuous Sulfex declad and Thorex core dissolutions of prototype Consolidated Edison fuel assemblies were made to complete the series of runs. The effective area of cylindrical UO/sub 2/ pellets dissolving in nitric acid was estimated from experimental rate measurements as a function of the fraction dissolved. A prototype SRE fuel rod was hydraulically expanded about 45 mils at 1300-psig pressure. Flooding capacities were determined for the compound extraction scrub columns with the acid Thorex flowsheet. A controlled cold-bath was installed for the condensation pressure analyzer to be used for UF/sub 6/ stream analysis. Tracer studies with the 8-in.-diameter by 84-in.high waste calcination vessel showed the solid deposition pattern to be a radial growth from the side wall and a vertical growth from the bottom. (For preceding period see ORNL CF-60-3-61.) (auth)
Date: July 28, 1960
Creator: Whatley, M E; Haas, P A; Horton, R W; Ryon, A D; Suddath, J C & Watson, C D
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Chemical Technology Division, Unit Operations Section Monthly Progress Report, August 1961

Description: Engineering studies of a 6-in.-ID countercurrent foam column were started. The capacity of Mark II Stacked Clone Contactor was found to be limited by gradually increasing entrainment. Thoria sols were prepared from trough denitrator products in a conical bottom tank agitated by circulation through an external centrifugal pump. Experimental results agreed favorably with predicted results for the reaction of CO with CuO and fur the simultaneous reactions of H/ sub 2/ and CO with CuO. In a 2-in. dissolver, Modified Zirflex dissolution rates of Zircaloy-2 increased non-linearly with F/S. The 250-ton prototype shear was received and installed. Priorities were established for development work on graphite fuels. A total of 5 SR Core I fuel clusters were mechanically dejacketed from the second carrier shipment of SRE Core I fuel. Degradation of NaK to a solid or waxy form required that the slugs be ejected by the jackscrew. The NaK disposal system operated satisfactorily for the Iast ~3000 ml of NaK. A procedure for estimating the temperature rise of spent reactor fuels during shipping gives reasonably good results. A puIse column was operated with the light phase c nt-nuous using an external phase separator. Zirconium ates were dissolved by HF in molten salt at rates at least twice as great as for Zircaloy-2 metal in the same system. Magnesium additive to high sulfate Purex waste was tested. (auth)
Date: March 1, 1962
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
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Chemical Technology Division, Unit Operations Section Monthly Progress Report for August 1959

Description: The concentration gradients of uranyl ion in aqueous and organic solutions were analyzed by taking a macro photograph of the desired gradient by monochromatic (436 m mu ) light transmitted by the solution normal to the gradient in an appropriate diffusion cell. Two Druhm runs were terminated due to malfunction of the sodium metering system and the third run was terminated when the UF/sub 6/ nozzle ruptured. Calculations of particle temperature versus time relations for the flame denitration-calcination method of preparing metallic oxide from nitrate solutions indicate that the times required for heat transfer are controlled by the rate of radiant heat transfer to particle surfaces instead of by conductive heat transfer within the particles. A completed experimental study indicated that electrolysis in a cell with a mercury cathode and a platinum anode is a practical process for removing nickel from HRT fuel solution. The apparent diffusion coefficient of uranium loading on Dowex 21K was shown to be directly related to the resin size. An explosion of sufficient violence to blow apart the Pyrex pipe dissolver occurred during the fifth Darex dissolution of simulated SRE fuel probably from a rapid gas phase reaction between hydrogen and oxidizing gases such as NO/sub 2/. Materials handling flowsheets were completed for (A) decladding, washing, recanning and storing spent SRE uranium fuel slugs and (B) the shearing and leaching of stainless steel clad UO/sub 2/ and UO/sub 2/- ThO/sub 2/ fuels. A literature survey is being conducted dealing with reactor coolant and coolant loop contamination and decontamination. During run R-17 for calcination of evaporated Darex waste, the same as run R-16 which deformed the bottom calcination vessel except that one of the three added pressure probes was vibrated to keep it unplugged, the bottom of the calcination vessel did not deform, and there was …
Date: December 31, 1959
Creator: Bresee, J. C.; Haas, P. A.; Horton, R. W.; Watson, C. D. & Whatley, M. E.
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Chemical Technology Division, Unit Operations Section Monthly Progress Report for February 1959

Description: A gamma scintillation spectrometer was used to measure diffusivity of uranyl nitrate in water during preliminary capillary experiments. During Fluorox run FBR-22, 90.4% of the theoretical amount of UF/sub 6/ formed was collected in cold traps and chemical traps. Toroid tests of flame calcined mixed Th-U oxide showed low corrosion rates, small changes in particle size and a low solubilization of uranium, while denitration of uranyl nitrate in a fluidized bed resulted in particle growth with uniform layers of uranium oxide. A half-time of 30 min for uranium anion exchange was measured in differential bed studies of uranium sorption on Dowex 21K. The Darex Reference flowsheet operation resulted in chloride removal to less than 50 ppm in solvent extraction feed from APPR head- end treatment. Unirradiated prototype Consolidated Edison pins were dejacketed with 6 M H/sub 2/SO/sub 4/ with uranium losses to the dejacketing solution of approximately 0.2%. An optimum procedure was developed for clarifying large batches of solvent extraction feed by sand bed filtration. Sheared sections of stainless steel clad UO/sub 2/ were completely leached in onehalf the time required for equal lengths of stainless tubes containing uncrushed pellets. Abrasive disc wheel to metal removal ratios were measured at cutting rates from 10 to 60 in./min. Dissolution of Zircaloy-2 dummy fuel elements in an INOR-8 dissolver with the NaF-LiF salt system resulted in vessel wall corrosion rates of 1-2 mils/run (approximately 8 hr of HF exposure). At a heat generation rate of 60 Btu/hr/gal of solid wastes, the maximum temperature rise in a 0.75 ft radius infinite cylinder (k = 0.1 Btu/hr sq ft ction prod- F) was 1270 ction prod- F in soil, 1150 ction prod- F in rock, and 1020 ction prod- F in salt. (For preceding period see CF-59-1-74.) (auth)
Date: June 11, 1959
Creator: Bresee, J. C.; Haas, P. A.; Watson, C. D.; Whatley, M. E. & Horton, R. W.
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Chemical Technology Division, Unit Operations Section Monthly Progress Report for May 1959

Description: The measured diffusivity of uranyl nitrate in water at 25 ction prod- C was 0.7 x 10/sup -6/ cm/sup 2//sec with about 40% average deviation. A program was started to develop nonnuclear uses for depleted uranium. Two continuous DRUHM reaction runs were terminated due to erratic operation of the sodium metering system. In the second Fluorox run with crude UF/sub 4/ which lasted for 29 hr, a total material balance of 94.8% was obtained and 17.9% of the theoretical amount of UF/sub 6/ was collected in cold traps and chemical traps. Room temperature flow rate-pressure drop calibrations of a multiclone (thirteen 0.60-in. diam hydroclones in parallel) for installation with the HRT replacement circulating pump were completed. Mixed oxides of U : Th = 0.08 : 1 and all have low yield stresses of 0.02 to 0.05 lb/sq ft compared to 0.2 to 1.0 lb/sq ft for normal Th-U or Th oxides of 1.5 to 2.5 micron mean diameter. The rates of uranium anion exchange from solutions containing between 0.025 and 0.20 M sulfate were measured and apparent uranium diffusion coefficients between 1.2 x 10/sup -7/ cm/sup 2//sec and 1.6 x 10/sup -7/ cm/sup 2//sec were calculated. In bench scale studies, the Darex reference flowsheet was successfully applied to stainless steel-clad UO/sub 2/ fuels (Yankee Atomic) and to aluminumuranium foreign reactor fuels. The corrosion of titanium A-55 was measured in the vapor and liquid phases of a modified boiling Thorex dissolvent (13 M HNO/sub 3/, 0.04 M F/sup -/, 0.1 M H/sub 3/BO/sub 3/) containing 0.0, 0.5, and 1.0 M thorium from dissolved Consolidated Edison pellets and the maximum corrosion rate was 0.6 mils/ month. Siliceous filter cakes resulting from the filtration of Darex solvent extraction feed solutions through porous metal filter elements were easily washed to a uranium loss of …
Date: August 25, 1959
Creator: Bresee, J C; Haas, P A; Horton, R W; Watson, C D & Whatley, M E
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Chemical Technology Division, Unit Operations Section Monthly Progress Report, July 1960

Description: A critical review of the literature revealed no experiments on uranyl ion transfer from an aqueous to a tributyl phosphate phase which positively measured the kinetics of the chemical reaction at the interphase. Drawing isorhythmic lines on a three component diagram gives a complex correlation for the compaction of three sizes of glass beads. Neither the use of thoria sols nor high feed solution concentrations of thorium nitrate gave any significant increase in mean particle diameters over those obtained from nitrate solutions of lower concentrations in flame denitration. A hydraulic film resistance has been detected in the anion exchange of uranyl sulfate into Dowex 2lK, and chloride elution was found to give a higher apparent uranium diffusion coefficient than nitrate elution. The rate of dissolution of mixed thorium-uranium oxides was determined as a function of the per cent of mixed oxides dissolved. Mixing in tanks packed with boron glass Raschig rings is being continued. The SRE hydraulic dejacketer has been operated successfully with prototype fuel rods. Excessive foaming was encountered when sheared stainless-clad UO/sub 2/ was suddenly contacted with boiling 13 M nitric acid. While attempting to shear a prototype Yankee subassembly with Kanigan brazed diffusion bonded joints, a five tube aggregate was formed at one of the two ferrule locations sheared. Of the 91 protective coatings exposed to ionizing radiation from the HRE, 25 of the coatings outside of the shield and 10 coatings inside the shield exhibited satisfactory resistance. HETS values in the acid Thorex flowsheet are reported. Waste calcination of simulated Purex waste in a 7-in.-diameter vessel gave rates slightly higher than predicted by the radial deposition model because of loss of feed due to excess foaming. (For preceding period see CF-60-6-11.) (auth)
Date: October 27, 1960
Creator: Whatley, M E; Haas, P A; Horton, R W; Ryon, A D; Suddath, J C & Watson, C D
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Chemical Technology Division Unit Operations Section Monthly Progress Report June 1956

Description: The primary objective of this report is the monthly distribution of experimental data as acquired during that period in the course of engineering studies. Much of the data is of preliminary nature and, therefore, reasonable care should be exercised in its application. You are invited to contact the individual authors for substantiation.
Date: June 1, 1956
Creator: Eister, W. K.; Long, J. T.; Nurmi, E. O.; Suddath, J. C. & Watson, C. D.
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Chemical Technology Division, Unit Operations Section Monthly Progress Report, June 1961

Description: An interfacial viseometer was built for use in an interfacial phenomena study. Installation of a 6-in.-ID foam separation column system was completed. The dispersiondrying-sintering characteristics of six low-nitrate batches of thoria sol material were studied. The average effective porosity of the CuO pellets used for reactor helium purification was determined to be 0.0545 for H/ sub 2/ transport and 0.0526 for CO transport. In continuous Zirflex dissolution studies, no H/sub 2/O/sub 2/ decomposition was observed when 10% H/sub 2/O/sup 2 was fed into boiling dissoivent through a water-cooled nozzle and the oxygen concentration in the scrubbed off-gas could be used to control the H/sub 2/O/sub 2/ concentration in the dissolver. The free fluoride in Zirflex solutions must be maintained above 1 molar in order to prevent uranium precipitation at low concentrations of uranium even though the F/sup -//U ratio exceeds 100. Chopped stainless steel-clad UO/sub 2/ sections were leached in a 4 stage pyrex leacher model using 6, 7, and 8 M nitric acid as the dissolvent. The temperature distribution expected within fuel elements consisting of square arrays of tubes was calculated for shipping conditions assuming heat to be transferred only by radiation. HETS values were calculated for uranium stripping under 5% TBP flowsheet conditions. Very fine particles were obtained by quenching fused salt droplets in water. A waste calcinatron run was made using TBP-25 waste and the close coupled evaporator-calciner system. (auth)
Date: January 23, 1962
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
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