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HYDRAULIC CYCLONES FOR THORIUM OXIDE PARTICLE SIZE CLASSIFICATION

Description: Results are reported concerning studies of hydraulic cyclones (hydroclones) for application to particle size classification of ThO/sub 2/. Tests were run with a 0.50-in. diam. hydroclone. It was shown that a single pass through this hydroclone would reduce the material greater than 10 mu from 12 wt.% to less than 1% while the mean diameter was reduced from 1.7 to 0.9 mu . When the overflow (fine) fraction was again pumped through the hydroclone, the overflow solids from the second pass were 98 wt.% less than 2 mu in diameter. The mean diameter was reduced from 0.9 mu to about 0.7 mu by the second pass. A yield of 5 to 7 wt.% of solids (to the overflow streamn) and a ratio of overflow to feed volume of 0.25-0.30 were observed during the hydroclone tests. Although this low yield is undesirable, recommendations are made that would increase the yield sufficiently to make desirable the incorporation of hydroclones in the ThO/sub 2/ production flow sheet. (auth)
Date: February 1, 1958
Creator: Bennett, L.L. & Thomas, D.G.
Partner: UNT Libraries Government Documents Department

COMMENTS ON THE ANGLE OF REPOSE OF AQUEOUS ThO$sub 2$ SLURRIES

Description: aqueous thorium oxide slurries have arisen in connection with the design of the lower portion of the blanket pressure vessel and its associated piping. The literaiure review on the angle of repose of various dry solids by Mrs. B. S. Neumann in J. J. Hermans' book on''Flow Properties of Dispersed Systems'' is summarized. Mrs. Neumann points out that both a dynamic and static angle of repose have been observed with the angles for dynamic systems being larger than for static systems. Results are reported for two different types of experiments with slurry discharged from run 200A-14 which gave static angles of repose of 45 to 50 deg and dynamic angles of 65 to 75 deg . (auth)
Date: February 14, 1958
Creator: Thomas, D.G.
Partner: UNT Libraries Government Documents Department

Study of Dispersant Agents for Thorium Oxide

Description: S>A preliminary study of dispersing agents for thorium oxide was completed and several of the dispersants have possible uses. Also many of the industrial dispersing agents tested are not usable with thorium oxide due to induced behavior causing balling and caking. The effects of nitric acid concentration were observed to also effect each dispersing agent. (auth)
Date: August 1, 1959
Creator: Bate, L. C. & Leddicotte, G. W.
Partner: UNT Libraries Government Documents Department

SOME EXPERIMENTS ON THE ACCURACY OF THORIA SLURRY SAMPLES

Description: Tests were performed on a thoria slurry flowing in a pipe to determine the magnitude of the possible error involved in the sampling process. Evidence indicates that a correct sample is obtained by withdrawing the sample isokinetically (i.e., by facing the sampler into the flow and adjusting the sampler velocity to match the ambient velocity) provided that the sampler is larger than some minimura diameter that is dependent on the mean eddy length and/ or the mean particle size. (auth)
Date: April 21, 1960
Creator: Wichner, R P
Partner: UNT Libraries Government Documents Department

COMPENDIUM OF EXPERIMENTAL RESULTS OF THE CIRCULATION OF AQUEOUS THORIUM OXIDE SLURRIES IN TOROIDS

Description: Data are presented for all toroid runs which circulated aqueous thorium oxide slurries between August 1954, and October 1956. In addition, a tabulation of the properties of numerous thoria preparatiors is presented. (auth)
Date: April 30, 1957
Creator: Moore, G.E.; Benson, R.F.; McDaniel, F.E. & Wheeler, S.H.
Partner: UNT Libraries Government Documents Department

LOW-TEMPERATURE CAPILLARY-TUBE VISCOMETER FOR AQUEOUS THORIUM OXIDE SLURRIES

Description: As part of the over-all program of investigation of the rheological properties of aqueous thorium oxide slurries, a capillary-tube viscometer was designed for routine determiation of shear diagrams of slurries over a temperature range of 30 to 85 deg C. A particular feature of this viscometer is the vertical oricntation of the capillary tube which minimizes the effect on the results obtained with dilate, rapidly settling slurries. (auth)
Date: May 30, 1958
Creator: Bennett, L.L.
Partner: UNT Libraries Government Documents Department

ARC CALCINATION OF THORIUM OXIDE

Description: An over-all description of the background material on the use of electrical arcs for heating of powders is presented as well as a summary of experimental studies on the arc calcination of thoria. Favorable results have been indicated both with heating thoria powder in an arc heated gas and with thoria formed into a consumable electrode. Use of a consumable electrode produces thoria particles 0.1 to 0.01 mu in diameter. It is recommended that additional electrodes be fabricated and further arc calcination tests be run to produce a quantity of product sufficient for evaluation. (auth)
Date: June 25, 1958
Creator: Johnsson, K.O.
Partner: UNT Libraries Government Documents Department

STATUS REPORT ON ThO$sub 2$ CAKING STUDIES

Description: Review of ThO/sub 2/ caking and sphere forming experiences in the 200 and 100 gpm loops shows that cakes and spheres always formed in the first 100 hours of the run or did not form at all, suggesting that processes in addition to oxide particle degradation were present. Many ThO/sub 2/ circulation tests in which no major difficulties were experienced suggest that preparation of oxides suitable for reactor use may have been accomplished, at least insofar as the caking problem is concerned. Further research is required to distinguish between oxide preparations. Evaluation of ThO/sub 2/ batches by cake resuspension index'' studies are described. A qualitative indication of the caking tendency of various batches of ThO/sub 2/ is given. Observations of ThO/sub 2/ sphere growth in stirred systems at atmospheric pressure indicate that added electrolytes have a strong influence. The results of ThO/sub 2/ cake disintegration tests are reviewed. A cake disintegration method has been used successfully twice to remove hard cake from inaccessible points in loops. The proposed program for caking studies in the 30 gpm loop, which is under construction, is outlined. The potential usefulness of several avenues for investigation of ThO/sub 2/ surface chemistry is indicated and the need for pursuing such investigations is pointed out. (auth)
Date: September 26, 1957
Creator: Morgan, C.S.
Partner: UNT Libraries Government Documents Department

PREPARATION OF THORIUM OXIDE FROM ORNL THOREX THORIUM NITRATE

Description: Thorium nitrate, removed from irradiated Th metal processed in the Thorex pilot plant, was converted to the oxide and then to the fluoride in one pilot-plant-scale and two laboratory-scale runs. Activity distributions, decontamination factors, and safety of the process are treated. (D.L.C.)
Date: February 13, 1957
Creator: McDuffee, W.T. & Yarbro, O.O.
Partner: UNT Libraries Government Documents Department