Browsing by Author "Fane, AG"

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    Laboratory studies and development of a catalysed fluorox process for the production of UF6
    (Australian Atomic Energy Commission, 1974-07) Batley, GE; Ekstrom, A; Fane, AG; Janov, J; Johnson, DA
    Laboratory studies of a catalysed Fluorox process for the production of UF6 are described. The rates of the reactions of UF4 with oxygen, of UO2F2 with hydrogen and of U03 with hydrogen were greatly increased by the presence of small quantities of platinum and other metal catalysts, thus making it possible to carry out these reactions at economical rates at temperatures significantly lower than have been used by other workers. The rates of the catalysed reactions were studied as a function of temperature, catalyst concentration and the particle size of the reactants. The conditions for the preparation of the catalyst were studied to optimise catalytic activity, and methods for the recovery of the caisajyst from the reaction mixture were also investigated. Preliminary studies in a bench-scale fluidised bed reactor have demonstrated the feasibility of using fluidised beds for the catalysed Fluorox process- The applications of these catalysed reactions to the commercial production of UF6 are discussed.
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    The production of sinterable uranium dioxide from ammonium diuranate in a pulsed fluidised bed reactor - interim report
    (Australian Atomic Energy Commission, 1970-12-01) Fane, AG; Alfredson, PG
    Results and operational experience are reported for the batchwise production of uranium dioxide from amanium diuranate in a pulsed fluidised bed reactor. Alternative proposals for the batch/continous operation are assessed and compared with continuous operation. The future development programme is outlined.
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    The production of sinterable uranium dioxide from ammonium diuranate in a pulsed fluidised bed reactor - interim report
    (Australian Atomic Energy Commission, 1970-12) Fane, AG; Alfredson, PG
    Results and operational experience are reported for the batchwise production of uranium dioxide for ammonium diuranate in a pulsed fluidised bed reactor. Alternative proposals for batch/continuous operation are assessed and compared with continuous operation. The future development programme is outlined.
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    The production of sinterable uranium dioxide from ammonium diuranate, Part 1 - a review of gas/solid contractors
    (Australian Atomic Energy Commission, 1974-04) Fane, AG
    This report reviews the performance characteristics of a variety of contactors used for gas/solid reactions. A critical assessment is made of their suitability for the conversion of ammonium diuranate to sinterable uranium dioxide in terms of their heat transfer and powder handling characteristics, and the capability of obtaining a high conversion efficiency consistent with continuous operation. The pulsed fluidised bed is judged to be particularly promising for future development.
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    The production of sinterable uranium dioxide from ammonium diuranate, Part 3 - continuous production in a pulsed fluidised bed reactor
    (Australian Atomic Energy Commission, 1975-02) Fane, AG; Le Page, AH
    The development of a 0.13 m diameter pulsed fluidised bed reactor for the continuous production of sinterable uranium dioxide from ammonium diuranate is described. Calcination-reduction at 670 to 680 ºC produced powders with surface areas of 4 to 6 m2 g-1 giving pellet densities in excess of 10.6 g cm-3. Sinterability was relatively insensitive to changes in operating conditions, provided the availability of hydrogen was adequate, for gas flow rates in the range 0.95 to 1.4 ℓ s-1, pulse frequencies of 0.5 and 0.75 Hz and mean residence times of the solids from 0.6 to 1.4 hours. Sinterability was shown to be improved either by use of higher input concentrations, or by use of a secondary flow of hydrogen (about 5 per cent of input) fed into the powder collection system and flowing countercurrent to the U02 product. The maximum throughput of 17 kg U02 h-1 (0.6 hours mean residence time) required only 120 per cent of the stoichiometric requirement at an input concentration of 50 vol.% with secondary hydrogen flow. Results are given for studies of the kinetics of reduction of calcined ammonium diuranate in hydrogen and the residence time distribution of solids in a pulsed fluidised bed. Estimates based on these data suggested that the overall conversion of ammonium diuranate to uranium dioxide in the continuously operated pulsed fluidised bed reactor was in excess of 99 per cent. Continuous stabilisation of the U02 product was demonstrated at 12 kg h-1 of U02, in a 0.15 m diameter glass stabiliser, using 10 vol.% air in nitrogen and a temperature of about 50ºC.
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    Thermal denitration of uranyl nitrate in a fluidised bed reactor
    (Australian Atomic Energy Commission, 1974-07) Fane, AG; Charlton, BG; Alfredson, PG
    Commissioning and operating experience are described for the thermal denitration of uranyl nitrate in a 0.1 m diameter fluidised bed reactor. The effects of operating temperature, uranyl nitrate concentration and feed rate, nozzle air to liquid flow ratio, and the addition of sulphate to the feed, on the characteristics of the product and equipment performance were examined. Particle growth was a predominant feature which was strongly influenced by operating temperature. Changes in the main process variables exerted a minor influence on other properties of the product. The addition of sulphate to the uranyl nitrate feed solution produced an increase in surface area, and a decrease in pour and tap density. The wall-to-bed heat transfer coefficient was in the range 190 to 265W nf 2K-1, and shown to be an inverse function of the average particle size.