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Subcontract Work by the Ferrotherm Co.

Description: The Ferrotherm Company is undertaking a design study of a test radiator. Since January 21, 1955, preliminary designs of several radiators have been completed prior to the selection of one for the final design study. Ferrotherm has been given prototype design specifications for structural design, typical in-flight prototype performance specifications for core-size estimates, test core specifications for their design study, and a method whereby radiators may be evaluated. From analysis of the prototype specifications a matrix will be selected for the test core design study. Although the analysis has narrowed to both a plate-and-sheet-metal fin and a plate-and-pin-fin core geometry, Ferrotherm is more or less committed to pin-fins.
Date: April 20, 1955
Creator: Shaw, R.H.

VARIABLE MODERATOR REACTOR DEVELOPMENT PROGRAM. Quarterly Progress Report No. 1

Description: Development of the boiling water UO/sub 2/ fueled Variable Moderator Reactor (VMR) is conducted under contract for the USAEC. The initiation and progress of work under Phase I of the contract, Physics and Kinetic Analysis and Initial Evaluation,'' and the preparation for Phase II, Critical Experiment and Analysis of Results,'' are reported. A hydrodynamic flow sheet representing the sequence of calculations for the BOCH program was prepared. A preliminary block diagram of the kinetics model of the VMR was prepared. Work is reported on the PUREE code which is designed to give an accurate representation of the physics of the VMR core. A fuel element fabrication speciftcation was prepared and released for quotations. A study was made to select the most appropriate material for void simulation throughout the range of interest in the VMR. (W.D.M.)
Date: August 31, 1959

Influence of Radiation Upon Corrosion and Surface Reactions of Metals and Alloys

Description: A discussion of various factors in corrosion of irradiated metallic surfaces is presented. The usual mechanisms of metallic corrosion, such as direct chemi-cal reactions, direct solution (mass transfer), and electrochemical mechanisms, are considered in relation to the effects of light and x rays. In addition, corrosion of reactor materials in aqueous materials is considered. The effect of irradiation on gas -solid reactions is discussed as well as proton irradiation effects on surface reactions. Several tables and graphs are included. (J.R.D.)
Date: January 1, 1957
Creator: Simnad, M. T.

Calculation of Effect of Fuel Burnup on Fuel and Poison Distributions and on Flux Distribution in the Marine Reactor

Description: The changes in fuel and poison distributions and the changes in flux shape which accompany the consumption of fuel are studied. The technique employed is a perturbation calculation based on a one-velocity group treatment of the neutrons. The geometry is a spherical core surrounded by an infinite reflector. The programming forms for the IBM-650 which performs the computations using the Wolontis interpretative system are included. Two sample calculations were worked out using the code described and the results are plotted. (M.H.R.)
Date: January 29, 1957
Creator: Hinman, G.

Absorption Spectra of Plutonium and Impurity Ions in Nitric Acid Solution

Description: The absorption spectra for Pu(III), (IV), (VI), and the red Pu(IV)- peroxy complex were determined in HNO/sub 3/ solution. Extinction coefficients for the above species of Pu were measured. Temperature has little effect on the spectra, but variation of acidity causes shifting of absorption peaks and some changes in the extinction coefficients. The absorption spectra and extinction coefficients in the region 390 to 1200 m mu were measured for chromic, nickelous, manganous, calcium, lanthanum, aluminum, ferrous. ferric, and permanganate ions in HNO/sub 3/ solutions. In addition, the effects of nitrite, oxalic acid, sulfamic acid, hydrogen peroxide, and various HNO/sub 3/ concentrations on the extinction coefficients of some of these ions were determined. The chromic, nickelous, ferrous, and permanganate ions, and ferric ion with oxalic acid, have sufficiently high extinction coefficients to cause inaccuracies in valence determinations of Pu in solutions containing high concentrations of these ions, unless corrections are made. (auth)
Date: July 31, 1956
Creator: Myers, M. N.

Fission Products Recovery From Radioactive Effluents

Description: Processes are described for the recovery of cesium137 from Purex type, first cycle waste solutions which result from the solvent extraction reprocessing of reactor fuels. Flowsheets are presented for recovering cesium from neutralized wastes by coprecititation with zinc ferrocyanide or from acidic solution by precipitation with zinc ferricyanide or zinc cobalticyanide. Further processing converts the cesium to cesium chloride, a stable form suitable for use in high intensity gamma irradiation sources. Modification of the cesium recovery process enables isolation of other valuable products including rare earths, cerium-144, and strontium-90 activities. Experience at Hanford Atomic Products Operation in the use of similar procedures for rge to the ground is described. A comparison of objectives and gested for fission product recovery is made. The effect of recovering certain fission products, particularly longlived nuclides, from effluents on temporary or long term storage or disposal of the effluent is discussed. (auth)
Date: October 31, 1958
Creator: Moore, R. L. & Burns, R. E.

Gas Cooled Power Reactor Coolant Choice

Description: The current status of helium and carbon dioxide technology is described in the light of the Gas Cooled Reactor Program requiremoents. The problem of containing high-pressure helium at high temperature is discussed, and it is concluded that, by proper attention to the design, construction and maintenance of a plant, a high degree of helium leak-tightness can be achieved at small additional cost when compared with a carbon dioxide system. What is more, the cost of making up helium losses in a practically achievable system is estimated to be small compared with other fixed and operating costs. Graphite-carbon dioxide reaction data are reviewed. It is shown that carbon dioxide at atmospheric pressure and low flow rates should be compatible with a graphite mooderator up to 525 C. No data are available at the high pressures and fiow rates that would be encountered in power reactors. Significantiy higher oxidation rates may result, however, perhaps limiting bulk moderator temperatures to 450 to 500 C. Improved carbon materials, protective coatings and inhibitors, and/or operating practices may be developed that will allow significant future increases in these limiting temperatures. (auth)
Date: June 12, 1958
Creator: Heacock, H. W. & Nightingale, R. E.

Hanford Neptunium Oxalate-Oxide Process Experience

Description: The over-all recovery process consisted of isolation from Purex plant solutions by solvent extraction, to yield an impure neptunium nitrate solution contaminated principally with U, Pu, and fission prcducts; purification by anion exchange; precipitation of nepturium(IV) oxalate; and calcination of the oxalate to yield NpO/sub 2/. The oxalate precipitation process investigations and results are described. (W.L.H.)
Date: July 1, 1959
Creator: Pollock, C. W. & Schneider, R. A.

A Hydraulic Power Unit for Solvent Extraction Column Pulse Generators

Description: A power unit comprised of a reciprocating hydraulic cylinder controlled by hydraulic, mechanical, and electrical elements was developed to drive pulse generators for solvent extraction columns in the Purex Hot Semiworks. Design bases included remote control of continuouslyvariable pulse amplitudes between 1/ 2 and 1/2 inches, and pulse frequency up to 120 cycles/min. Each of nine power units operated 30 to 60 million cycles without serious difficulty, although minor modifications and corrections were made during scheduled shutdowns of the Semiworks. Operational irregularities, such as erratic or drifting amplitudes, occurred with sufficient frequency to indicate deficiencies in the original design. The triangular pulse wave which is characteristic of the power unit was suspected on several occasions as having an adverse effect on extraction column performance. However, no correlation was found to show that column performance is adversely affected by the triangular pulse. (auth)
Date: August 23, 1957
Creator: Kelly, V. P.

Hydrogen Production in the Calcium and Magnesium-Nitric Acid Reactions (Deleted Version)

Description: For greater understanding of possible explosion hazards, data are needed of the volume of H/ evolved in the Ca and Mg reactions with nitric acid. Nearly five liters of H/sub 2/ per mole of Ca are produced when 16M nitric acid reacts with Ca metal. The hydrogen evolved slowly increases with decreasing nitric acid to below 4M nitric acid, when a rapid increase occurs. The Mg--nitric acid reaction produces only one liter of H/sub 2/ per mole of Mg with 2M nitric acid, and the volume of H/sub 2/ decreases with increasing nitric acid concentration. (L.T.W.)
Date: August 19, 1955
Creator: Myers, M. N.

Chemical Stability of Purex and Uranium Recovery Process Solvent

Description: The desirability of operating the Purex columns at higher temperatures, 50 to 70 deg C, made it necessary to obtain data on the stabiliyy of solverts at these higher temperatures. Since the present diluent will not be entirely safe at the upper temperature limit, a number of diluents with higher flash points were investigated. (J. E. D.)
Date: March 1, 1955
Creator: Moore, R. H.

The Chemistry of Tributyl Phosphate: A Review

Description: The preparation, purification, and chemical properties of THP have been reviewed with emphasis on the hydrolytic reactions. TBP is chemically a very stable compound as evidenced by its thermal stability and resistance to oxidation. The most important reactions are hydrolytic which cleave the butyl or butoxy group and normally produce butyl alcohol together with dibutyl and monobutyl phosphate (DBP and MBP, respectively), and eventually H/sub 3/PO/sub 4/. Hydrolysis occurs in either the organic phase or the aqueous phase and is first order with respect to the ester. Although the rate in the aqueous phase is much faster than in the organic phase, the solubility is so low in aqueous solutions that the organic phase reactions become more important. Acid hydrolysis depends on both the nature of the acid and the concentration. The order with respect to acid concentration is close to one but often less than one. Hydrolysis is catalyzed by both acids and bases. In the latter case, the reaction occurs only in the aqueous phase and normally stops with the formation of dibutyl phosphate. The hydrolysis rate increases greatly as the temperature is raised and an activation energy of the order of 20 kcal is often found. The rates observed in the presence of 5 M acid at 60 and 70 deg C may be high enough to cause some concern in solvent extraction technology, since the product, dibutyl phosphate, has undesirable properties. Impurities produced during manufacture or by thermal degradation during purification such as the pyrophosphates, if present, would yield the same objectionable products as TBP hydrolysis, but at a faster rate. Included in the survey is a selected tabulation of physical properties of TBP. (auth)
Date: October 27, 1955
Creator: Burger, L. L.

Damage Effects to Graphite Irradiated Up to 1000 C

Description: Irradiation effects at 500 deg C in experiemtal graphites with varied density, crystallinity, surface area, and pore distribution are discussed. Changes in macroscopic properties are dependent upon the initial crystallite structure; however, the mechanism by which the increase of interlayer spacing and decrease of apparent crystallite size effect these changes is not well understood. Macroscopic properties are also dependent upon the arrangement of crystallites and whole coke particles within the over-all structure which raniation may change slightly. Graphite irradiations in the Materials Testing Reactor extend exposure temperatures from 800 to 1000 deg C. The temperature coefficient of property damage decreases with temperature, aad only slightly less damage occurs at 1000 deg C than at 500 deg C. Thermal conductivity decreases by a factor of 50 with 30 deg C irradiation, a factor of 3 with 500 deg C irradiation, and a factor of 2 with 750 deg C irradiation. Within the irradiation temperature range 500 to 1000 deg C, the contraction rate after the first 1500 Mwd/t is measurably the same: C/ sub 0/ spacing expands slightly: and apparent crystallite size decreases by one- half. The total stored energy content is decreased with increased irradiation temtemperature. The way in which damage effects in irradiated graphite are distributed may be measured by the ease with which they may be thermally annealed. By estimating an activation energy for a given temperaturetime annealing and measuring the amount of property annealed, at repeated increasing temperatures, it has been possible to characterize the damage with a damage distribution curve. Thermal annealing experiments on graphites with varied exposures and temperatures of irradiation have included property measurements of dimensions, thermal conductivity, interlayer spacing and crystallite size, A damage mechanism is discussed which attempts tp correlate and explain the changes in properties resulting from graphite irradiations at high ...
Date: October 31, 1958
Creator: Nightingale, R. E.; Davidson, J. M. & Snyder, W. A.

Density Monitor for Purex HA Column

Description: A densimeter system is described which was developed for use on HA column. Reproducibility of instrument readings is plus or minus 2 1/2% of recorder span for pulser frequencies of 44 to 104 cycles per minute. The effects of column pulsations and column static pressure at the feed point are small. Simulated column feed point static pressure of 10 psig caused improved precision due to added damping of float oscillations. (auth)
Date: July 16, 1958
Creator: Huck, C. E.

Aqueous Processes for Separation and Decontamination of Irradiated Fuels

Description: . A review of recent dcvelopments and improvements in aqueous processes for accomplishing separation and decontamination of irradiated fuels from power reactors is presented Research and development is currently being pursued in tbe United States on three distinct types of fuel processing methods; pyrometallurgical processes, fluoride volatility processes, and aqueous processes. Although the ultimate role of these processing methods in a nuclear power economy cannot be accurately assessed at the present time, it is felt that the proven reliabilita and versatility of aqueous processes guarantees them a prominent role in power reactor fuel reprocessing. Aqueous solvent extraction processes, for example, are ideally suited for installation in central processing plants which are designed to handle fuels from a number of power reactors generating a total of several thousand megawatts or more of power. Under these circumstances, nuclear fuels can be processed by continuous processes at high throughputs and at high on-stream efficiency and therefore at low unit cost. (auth)
Date: October 31, 1958
Creator: Cooper, V. R. & Walling, M. T., Jr.