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By R. D. MacDonald, John Dasher, A. M. Gaudin

ION exchange is a widely used unit operation in water treatment and elsewhere in chemical industries. It has occasionally been used in hydro-metallurgy for treating plating, pickling, and rayon wastes Concerning ion exchange in extractive hydrometallurgy—for treating ore leach solutions— the literature prior to the Geneva Conference has given only hints."-" Yet most of the ore leach plants now being built or completed in the last three years use ion exchange for this purpose. Most of these plants are used for extracting uranium. The overall process for leaching low grade uranium ores and the history of its development have been given in the authors' previous papers.',' The object of this paper is to discuss certain engineering aspects of the new application of ion exchange to recover dissolved values from ore leach solutions. Necessarily the illustrations will be taken from the first application—to uranium metallurgy. Although ion exchange processes have been devised in which separation of spent residue from pregnant liquor is not required, as in the RIP process,"-'I only ion exchange operation, in which the resin is contacted with a clear solution, will be discussed in this paper. Uranium exists in acid leach liquors mainly as the cation UO," and can be adsorbed completely by cation exchange resins, but the adsorption is not selective as other cations such as Fe++, Fe+++, Al+++, Mg++, Mn", and Ca++ are also adsorbed. Uranium, however, forms complex anions with sulfate, phosphate," Carbonate"~"~ and even with chloride if the solution is strong enough.15 These anions can be adsorbed by anion exchange resins. The strong base anion exchangers have a very strong preference for these complexes and hence this adsorption is very selective. In this paper, the examples concern acid sulfate leach liquors from which uranium is adsorbed as UO,(SO,),-% and UO,(SO,),". Materials and Equipment Ion Exchange Material—Ion exchange materials include natural and synthetic; organic and inorganic; cationic and anionic; and weak, intermediate, and strong varieties. They consist of fragments or beads normally in the size range —16 to $50 mesh. The newer varieties have been developed to have greater stability, chemical strength, and/or capacity than earlier varieties. The resin used for uranium recovery is a strong base anion exchanger.* To make * Such as Rohm and Haas Amberlite IRA-400 series, British Permutit DeAcidite FF. Permutit lonac SE. and Dow Nalcite SAR. this resin, styrene plus a few percent divinyl benzene are polymerized into long chains with occasional cross links. This resin in bead form is then reacted to introduce quaternary amine groups onto most of the aromatic rings.' These resins are water-avid gels of specific gravity of about 1.1, which shrink and swell by osmosis when the ionic content of the surrounding solution is changed. The beads which are shown in Fig. 1 can be broken like an onion by rapidly replacing 15 pct H,SO, with water. This organic gel can also be broken by mechanical handling as by a centrifugal pump. Otherwise it is remarkably stable. It is unharmed by fairly strong acid or alkali, oxidizing or reducing agents, and heat up to 70°C. The strong base resin when completely in the chloride form (with a chloride anion on each quaternary amine group) holds over 107 g of C1- per dry kg. As all these chloride ions can be displaced by other anions, the resin has an exchange capacity of over 3 g equivalents per dry kg. However, the resin is sold and used by moist volume. The moist resin contains about 50 pct water, weighs about 43 lb per cu ft, has 40 pct voids, and an exchange capacity of over 1 g equivalent per liter of bed volume. Ion Exchange Equipment—Ion exchange equipment used for recovery of uranium from leach solutions is substantially identical to that developed for water treatment and other applications.'" The resin beds are held in closed tanks or columns which, in the uranium plants, have been standardized at 7 ft diam and 12 ft high. The resin bed

Jan 1, 1958

By W. L. Kerlie, J. H. Richards

The variation in hydrogen content of basic open-hearth steels during refining and the effect of changing from steam to air atomization were studied. The water content of the furnace atmosphere, the slag basicity, and the degree of oxidation of the slag-metal system largely control the hydrogen in the steel. SMALL amounts of hydrogen have an adverse effect on the ductility of steel and a wide range of hydrogen contents has an adverse effect on the internal soundness of both ferrous and nonferrous castings. This has been of major concern to the metal industry, both manufacturers and fabricators, for many years. As one of the results of continuing investigations of the hydrogen problem, much has been learned about methods of reducing the hydrogen content of liquid metals below the relatively high levels that are normally associated with such phenomena as rising ingots and excessive porosity in sand casting. However, it was not until a reliable and simple method for sampling and analyzing liquid metal was developed that much progress was possible in quantitatively evaluating the effect of steelmaking practice on hydrogen contents at levels below 6 to 8 ppm. Throughout all the work described in the following presentation the Geffner pintube technique was used to obtain samples of liquid metal1 * and the tin-fusion method, developed at Massachusetts Institute of Technology,2 was used to analyze the samples. Before attempting a systematic experimental program for minimizing the hydrogen content of open-hearth steels, it was necessary to determine the variation in hydrogen in the open-hearth bath during the normal processing of a heat. The logs of ten heats are illustrated in Figs. 1 through 7. The number at each point on the graphs refers to the number of pintube samples analyzed for hydrogen. An increase in the hydrogen content of the liquid metal during the early period of refining is apparent in all heats. There is evidence of a decrease in hydrogen later in the refining period, see Fig. 2, for example. Therefore, the existence of a maximum hydrogen content at some intermediate time during the refining period is anticipated. To test for the existence of a maximum, the data illustrated in Figs. 1 to 5 were grouped together so that they could be examined on a collectively comparable basis. The grouping was effected, as illustrated in Fig. 8, by superimposing Figs. 1 to 5 so that the apparent hydrogen maxima coincided at a fixed position, indicated by the zero on the time axis. Also, by vertical adjustment until the graphs appeared to the eye to be superimposed, the hydrogen scale was made to show the change in hydrogen content. That is, a standard amount was subtracted from the hydrogen values for each heat. Therefore, Fig. 8 represents a generalized presentation of the data and, for this reason, cannot be used to predict the actual hydrogen content of the bath during refining, but rather to show the probable rate of change in hydrogen during refining. Statistical examination of the grouped data in Fi.g. 8 shows that the apparent. increase and suhsequent decrease in hydrogen are real and confirms the existence of a maximum in general. The average increase In hydrogen during the early period of refining is between 0.8 and 1.3 ppm per hr, and the

Jan 1, 1958

By W. B. Gogarty

With flow of non-Newtonian fluids in porous media, effective viscosities are needed for use in the Darcy equation. These viscosities depend on the rock parameters and flowing conditions. In this investigation, rheological and flow results were correlated to develop an expression for calculating effective viscosities. Surfactant-stabilized dispersions of water in hydrocarbon were used with consolidated sandstone cores of different permeabilities. The average shear rate in a core was related to the permeability and porosity of the core and the frontal velocity through the core. By using the correlation obtained for determining effective viscosity, experimental and theoretical values were compared for each fluid system by determining average and maximum errors. For the fluid system showing the largest average error, the correlation fit 38 experimental points with an average and maximum percentage error of 4.3 and 14.8, respectively. For the fluid system showing the least error, average and maximum percentage errors of 1.8 and 4.3, respectively, were calculated using 29 experimental points. INTRODUCTION Use of non-Newtonian fluids in the petroleum industry is not new. Fluids of this type have been used for many years as fracturing agents and drilling muds. Recently, attention has focused on the use of high molecular weight polymer solutions for secondary recovery. Results have been reported on studies relating to the flow behavior of polymer solutions in porous media.1-4 Each study gives the viscosity in the Darcy equation as a function of the rheological properties of the fluid, the characteristics of the porous medium and the pressure gradient. The functional forms of the reported expressions differ somewhat in each study. The first three studies used unconsolidated porous media while the fourth used a single consolidated core. Because of the limited information available on the flow of non-Newtonian fluids in porous media, further investigation was undertaken in this area. We selected non-Newtonian fluids that did not contain high molecular weight polymers in order to minimize core plugging. The over-all objective was to gain a better understanding of the flow behavior of non-Newtonian fluids in consolidated porous media. Specifically, our goal was to determine the relationship between the average shear rate in a core and the frontal velocity. Because of this goal, it was necessary to determine the effect of permeability on the shear rate-frontal velocity relationship. We wanted to replace the viscosity in the Darcy equation with an expression relating to the average shear rate in the core and the rheological properties of the non-Newtonian fluid. THEORY For a time-independent, non-Newtonian fluid, the apparent viscosity is a function of the shear rate. This relationship is given by µ = F(v')...........(1) With Eq. 1, a single value of shear rate determines the apparent viscosity at that shear rate. With flow in porous media, a spectrum of shear rates occurs at any average throughput. An average shear rate v' can be used to represent the spectrum of shear rates that exists within the core. By using v' and the rheological data given by Eq. 1, an effective viscosity is determined for the flowing fluid. If v' is the correct average, µe becomes the appropriate viscosity for use in the Darcy equation. Under these conditions, flow rate-pressure drop relationships can be determined for non-Newtonian fluids. HOW the correct average shear rate might be related to the frontal velocity through the core and the characteristics of the porous media will now be considered. Later, the experimental data are presented that indicate the validity of these

By M. Garfinkle, W. D. Klopp, W. R. Witzke

The tensile properties of binary W-Re alloys containing up to 33 at. pct Re were determined at temperatures from 78" to 3630°F. Elongations as high as 260 pct were observed in electron-beam-melted tungsten containing 23 at. pct Re when tensile-tested at 3630°F after a 1-hr anneal at 3090°F. All alloys tested under these conditions with rhenium contents between 20 and 28 at. pct exhibited elongations of at least 200 pct. These alloys also showed enhanced grain growth rates. The values of strain-rate sensitivity ranged between 0.2 and 0.3 for the alloys exhibiting high elongations. Houlezler, for swaged alloys tested just above the re-crystallization temperature, strain-rate sensitivities as high as 0.8 were observed. The high-temperature strengths of the high-rhenium-content alloys were also less than those of alloys with intermediate rhenium contents. ALLOYING with rhenium has two distinct effects on the mechanical properties of tungsten. One effect occurs in dilute solid solutions and is most clearly seen in the lowering of the hardness and of the ductile-brittle transition temperature at about 5 at. pct Re.1-3 The second effect occurs in the concentrated solid solution at about 25 at. pct Re, and is characterized by twinning and a larger decrease in the ductile-brittle transition temperature. An aspect of the high-rhenium-content alloy which has received little attention is the higher-than-usual tensile ductility at 3500°F.3 Anomalous high ductility has been observed in several other alloy systems. usually associated with a phase transformation or a solid-solubility limit.4'5 The phenomenon is now commonly termed superplasticity. High-strain-rate sensitivities6 and grain boundary sliding7 have been reported for materials that undergo superplastic deformation. Also, it has been found that superplastic materials usually have a very fine grain structure (less than 10 pm).8 and it has been proposedg that such a structure alone is sufficient for superplasticity. The purpose of the present study was to further characterize the high-temperature tensile properties of W-Re alloys to determine the conditions under which they might be superplastic. Tensile and selected strain-rate sensitivity tests were conducted on alloys containing 0 to 33.3 at. pct Re at temperatures from 78" to 3630°F. Grain-growth rates were also determined on most alloys at 3630°F. Fig. 1 indicates the compositions evaluated and their locations relative to the solvus line in the tungsten-rich end of the W-Re phase diagram. Twelve binary W-Re alloys containing up to 33.3 at pct Re were double electron-beam-melted and subsequently fabricated to 0.3-in. rod by extrusion and swaging. The starting materials were commercial powders of tungsten and rhenium with impurity levels as listed in Table I. The various blended W-Re compositions were hydrostatically pressed at 70 ksi. The pressed bars were drip-melted into 1.5-in.-diam ingots and then remelted into 2-in.-diam ingots at a chamber pressure of 10~5 torr. The ingots were canned in molybdenum and extruded to round bar at a reduction ratio of 6:l. The alloy extrusions were swaged to about an 80 pct reduction at 2100" to 2900°F. Buttonhead tensile specimens with a reduced section diameter of 0.16 in. and a gage length of 1.0 in. were centerless-ground from the swaged bars

Jan 1, 1970

No. Place Date Vol. 1. Wilkes-Barre, Pa May, '71 1 2. Bethlehem. Pa Aug., '71 1 3. Troy, N. Y Nov.,'71 1 4. Philadelphia, Pa Feb., '72 5. New York, N. Y.* May, '72 8. Pittsburgh, Pa Oct., '72 7. Boston, Mass Feb., '73 8. Philadelphia, Pa.* May, '73 9. Easton, Pa Oct.. '73 10. New York, N. Y.Feb., '74 11. St. Louis, Mo.* May, '74 12. Hazleton. Pa Oct., '74 13. New Haven, Conn Feb., '75 14. Dover, N. J.* May, '75 15. Cleveland, O Oct., '75

Jan 1, 1929

By Pol Duwez, Paul Pietrokowsky

Titanium and vanadium form a complete series of solid solutions at temperatures above 885°C. Below 885°C, vanadium is slightly soluble in a titanium (about 1.5 pct V at 650°C) and a two-phase a plus ß region extends to 18.5 pct V at 650°C. The alloys up to 15.0 pct V transform into a supersaturated a solid solution upon rapid cooling from the ß phase. Above 15 pct V the ß phase may be retained. The temperature at which the ß to a' martensite-type transformation takes place decreases steadily from 850°C for 0.5 pct V to 325°C for 12.7 pct V. IN the transition series of the periodic table, the six elements that have a body-centered cubic structure at all temperatures, namely chromium, vanadium, molybdenum, columbium, tungsten, and tantalum, fulfill the conditions required for the existence of complete series of solid solutions with the high temperature (ß) form of titanium. Up to the present time, complete solubility at temperatures above the a to ß transformation of titanium has been observed in the systems Ti-MO,1,2 Ti-Cb,2 Ti-W,³ and Ti-Ta.³ The two remaining elements, vanadium and chromium, have atomic diameters which are not as near that of titanium as the atomic diameters of the four other elements. Both are smaller than titanium and the difference, expressed in percentage of the titanium atomic diameter, is 12.3 pct for chromium and 8.2 pct for vanadium. On this basis, the least favorable conditions for solid-solution formation are therefore encountered in the Ti-Cr system. The early work on the Ti-Cr system4 revealed that up to about 1100°C the solubility of chromium in ß titanium is limited, and an intermetallic phase exists near the stoichiometric composition TiCr2. It was found later' that a continuous series of solid solutions extends across the diagram at higher temperatures, and TiCr2 forms by solid state reaction. It became apparent therefore that complete solubility would also be present in the Ti-V system. The present investigation confirms this possibility. The iodide-refined titanium used in this investigation was purchased from the New Jersey Zinc Co., New York. According to the manufacturer, a typical analysis of this product is 0.0065 pct Mn, 0.0022 pct Fe, 0.0015 pct Cu, and 0.0042 pct Pb. The Vickers hardness number (10 kg load) of the crystalline bar varies between 55 and 80. The vanadium metal was purchased from the Westinghouse Electric Corp., Lamp Div., Bloomfield, N. J. The purity of this metal is probably above 99 pct V. The oxygen content must have been quite low, since a bar about 1/4 in. square could be cold rolled into a ribbon 0.020 in. thick. To prepare the various alloys on the titanium-rich side of the diagram, the titanium rod was machined into cups 1 cm in diam and about 1.5 cm high. Pieces of vanadium, of the proper weight, were cut from the square bars and placed within the cups prior to melting. On the vanadium-rich end of the diagram, single pieces of the metals, in the proper weight pro-

Jan 1, 1953

By Zay Jeffries

THIS paper will include a brief discussion of Prof. Howe's paper on The Supposed Reversal of Inheritance of Ferrite Grain Size from that of Austenite.1 The general subject of grain refining in steel and iron will also be treated. The conclusions reached are stated in the following hypotheses which are discussed more in detail below. 1. The ferrite grain size in pure iron, the ferrite and pearlite grain size in hypoeutectoid steel, the pearlite grain size in eutectoid steel and the cementite and pearlite grain size of hypereutectoid steel are not inherited from the grain size of the mother austenite. 2. The only structural feature that is generally inherited from the austenite of hypo- and hypereutectoid steels on cooling through their transformation ranges is the position of the excess ferrite or cementite at the austenite grain boundaries, sometimes causing complete and sometimes incomplete networks which outline the old austenite grain boundaries. Rapid cooling through the transformation range will cause the non-inheritance of this structural (network) feature. 3. The austenite grain boundaries themselves are nearly always effaced in all steels and also in pure iron during the Ar transformations. 4. The grain-size refining of steel and iron is brought about by the combined. effect of non-inheritance of the transformation products on either heating or cooling, i.e., the austenite transformation .products do not inherit their grain size from the austenite on cooling through the transformation range for does austenite inherit its grain size from the products which form austenite on heating. 5. In general, in both iron and carbon steel the larger the austenite ,grain size, the larger will be the grain size of the transformation products on cooling. This, of course, assumes all other conditions constant except the austenite grain size. An exception is found to this general rule in very pure iron such as electrolytic iron. 1n this instance small austenite grains may form very large ferrite grains on cooling through Ar3.

Jan 11, 1917

THE subcommittee on Coal Mining, since its appointment, has been engaged in collecting data about subsidences in coal mines in this country, and it now feels that almost all of the available data about occurrences of this sort in bituminous mines has been collected. As most of the bituminous seams are nearly level, the records obtained give the problem in its simplest form, without complications due to the pitch of the seam. Similar data is being compiled for the anthracite regions and it is hoped that this will be ready for the 1927 meeting. Copies of the questionnaire, Appendix A, were mailed to all of the coal operators' associations, to most of the large operating companies and to many engineers, with the request that any data on the subject be returned to the committee, or that advice of any subsidences known be given. The replies to most of the questionnaires were general only, although some specific cases were given. Many of the companies were unable to reply to all questions, as they lacked the necessary data, but in nearly every case where accurate data was available, it was cheerfully furnished, and any additional information requested was secured. All specific cases of subsidence were followed up by correspondence, and in several cases by personal inspection. Figs. 1 to 31 were made from the information furnished. Table 1 gives measurements of elevations taken in one case at intervals from October, 1913, to May, 1918. With one exception, where the evidence cannot yet be released on account of a lawsuit, it is believed that the cases submitted with this report include practically all that have happened in bituminous coal mining in this country of which actual measurements were secured. Some of these have already been published in the excellent report by Young and Stoek,1 and some instances have been secured from other publications. In collecting these data, the subcommittee had the Engineering Societies Library extend the bibliography given in the bulletin mentioned above to date. This list is given in Appendix B.

Jan 2, 1926

By G. R. Kotler, W. A. Tiller, W. C. Johnston

Experiments carried out on 100 g samples of molten tin and Sn-Pb alloys showed that the magnitude of the field strength, H, does not effect the supercooling, aTn, at which the initial nucleus of solid forms. However, the nuwlber of nuclei forming per cc, n, is found to increase greatly with H for fixed ATN and to increase with ATN for fixed H. The value of n increases greatly with the presence of solute and is found to he indefiendent of the cooling rate of the simples. Further, the most effective time for stirring to enhance n is immediately following the initiation of recalescence. The effect of inducing nucleation with the aid of a mechanical impact both in the presence and absence of stirring has also been studied. All proposed mechanisms for the enhancement of n by physical means seem to be inadequate in accounting for these results. IN any real nucleation experiment there are two effects influencing the results that would not be predieted from classical homogeneous nucleation theory. These may be separated into chemical and mechanical effects. The chemical effects are twofold. 1) Nucleation catalysts are present which enhance the nucleation frequency of new grains over that predicted by classical homogeneous nucleation theory.' 2) Solute will restrain the growth of nuclei so that many others may form.2,3 The mechanical effects are also two-fold. 1) Vibration (sonic or ultrasonic) of the freezing liquid enhances the nucleation frequency of new grains over that given by the chemical effects alone.4-6 2) Macroscopic fluid-flow effects produce the same effect as l).'7' It is also possible to influence the nucleation experiment by certain physical effects such as the application of electric and magnetic fields.9 From classical homogeneous nucleation theory one would predict the following relationship between the nucleation rate, N1 (number of nuclei formed per unit volume per unit time), and bath supercooling, AT, for an isothermal experiment.

Jan 1, 1963

By L. W. Eastwood

The structure of eutectics has been studied by a number of investigators, and the complexity of the structural relationship of the components has been agreed upon, especially that of the "eutectic colony," type III of Portevin's1 classification. This paper does not attempt to alter the present classifications of eutectics; rather, it discusses the relationship between the macrostructure and the microstructure of the copper-cuprous oxide eutectic, and describes in detail the mechanism of the formation and the structure of the eutectic. Further, throughout the entire discussion it attempts to point out certain misconceptions in regard to the interpretation of the observed structure of the copper-cuprous oxide eutectic, one of the so-called "eutectic colony" types, and to correlate as much as possible the work done by the writer with that done by other investigators. Of the three types of eutectics listed by Portevin,2 the eutectic colony type has presented the greatest difficulty in interpretation. Although the copper-cuprous oxide eutectic is typical of the eutectic colony type in appearance, it may not be truly representative because the copper forms about 96 per cent of the eutectic and the cuprous oxide about 4 per cent. The interpretation of the origin and structure of the "eutectic colony" given here is strictly limited, therefore, to the copper-cuprous oxide eutectic. Macrostructure Fig. 1 shows the macrostructure of the eutectic at 3 diameters, the melt having been chill-cast into an iron mold, the resulting specimen sawed into two parts and the section polished and etched with the usual mixture of hydrogen peroxide and ammonium hydroxide. This specimen contains 0.48 per cent oxygen and is only slightly hypereutectic. If such a melt is allowed to cool slowly, large macrograins will form without the columnar structure of Fig. 1 and the well-known phenomenon of liquation will occur, forming copper oxide dendrites at the top and copper

Jan 1, 1934

By O. B. Hopkins

Essentially all production for Peru came from the three established fields in coastal northwestern Peru (Fig. 1). These fields are known as La Brea-Parinas, Lobitos, and Zorritos, in order of importance. Together they produced 13,496,880 bbl., as compared with 15,838,605 bbl. in 1938. Zorritos Field.—Of the total production shown on Table 1, the Zorritos field was responsible for a relatively negligible amount estimated at 40,000 bbl. This small field, which is over 50 years old, was purchased by the Peruvian Government in the spring of 1939 from the Piaggio interests. The Government operated this field along with its near-by National Reserve areas, largely under supervision of Department of Mines officials, and the total production rate for both old and newa-areas was estimated to have increased by Oct. 1 to 166 bbl. per day. as compared with the 1938 average of 110 bbl. per day. Construction is said to have begun on a refinery that is to have a capacity of 1000 bbl. per day and is to include a gasoline-extraction plant, and on a pipe line to bring fresh water 20 miles from the Tumbes River. Lobitos Fields.—The Lobitos fields, some 70 miles south of Zorritos, produced approximately 2,650,000 bbl., or almost the same amount a* in 1938. La Brea-Parinas.—The International's La Brea-Parinas property, immediately south of the Lobitos property, produced 10,806,880 bbl., or 80 per cent of Peru's production. During the year 73 wells were drilled on the Estate, mostly in the semiproved area: 44 by rotary, 13 by cable and 16 by star rigs, as compared with 34 by rotary, 11 by cable and 20 by star in 1938. The most important of the several semiexploratory wells sunk was No. 3075, which late in December was brought in at a depth of 4500 ft. with an initial production of 1500 bbl. per day, based on

Jan 1, 1940

By O. B. Hopkins

Essentially all production for Peru came from the three established fields in coastal northwestern Peru (Fig. 1). These fields are known as La Brea-Parinas, Lobitos, and Zorritos, in order of importance. Together they produced 13,496,880 bbl., as compared with 15,838,605 bbl. in 1938. Zorritos Field.—Of the total production shown on Table 1, the Zorritos field was responsible for a relatively negligible amount estimated at 40,000 bbl. This small field, which is over 50 years old, was purchased by the Peruvian Government in the spring of 1939 from the Piaggio interests. The Government operated this field along with its near-by National Reserve areas, largely under supervision of Department of Mines officials, and the total production rate for both old and newa-areas was estimated to have increased by Oct. 1 to 166 bbl. per day. as compared with the 1938 average of 110 bbl. per day. Construction is said to have begun on a refinery that is to have a capacity of 1000 bbl. per day and is to include a gasoline-extraction plant, and on a pipe line to bring fresh water 20 miles from the Tumbes River. Lobitos Fields.—The Lobitos fields, some 70 miles south of Zorritos, produced approximately 2,650,000 bbl., or almost the same amount a* in 1938. La Brea-Parinas.—The International's La Brea-Parinas property, immediately south of the Lobitos property, produced 10,806,880 bbl., or 80 per cent of Peru's production. During the year 73 wells were drilled on the Estate, mostly in the semiproved area: 44 by rotary, 13 by cable and 16 by star rigs, as compared with 34 by rotary, 11 by cable and 20 by star in 1938. The most important of the several semiexploratory wells sunk was No. 3075, which late in December was brought in at a depth of 4500 ft. with an initial production of 1500 bbl. per day, based on

Jan 1, 1940

By W. B. Weeks, H. K. Shearer

The year 1937 brought to south Arkansas increased drilling activity and production. Oil production amounted to 12,159,440 bbl., an increase of 1,504,500 bbl., or 14.1 per cent over 1936. This was the largest production since 1931, and the first annual increase since 1925, when the deeper sands at Smackover were developed. There were 177 wells completed during the year, with 103 oil wells, 6 gas wells, and 68 dry holes, an increase of more than 100 per cent over 1936. Of the 56 wildcat wells drilled, 52 were dry and 4 produced oil. Two new fields, one important extension and three minor extensions were discovered. The trend toward deeper drilling is shown by the fact that 97 wells were more than 5000 ft. deep, including 80 over 6000 ft. and 13 over 7000 ft., although the depth record of 7973 ft., made in 1935, was not exceeded. Geological Section Deeper and more extensive drilling during the past few years, not only in south Arkansas but also in adjacent parts of north Louisiana and east Texas, has furnished much important geological information and has brought out some very unexpected facts in regard to structural and depositional conditions in the series of formations laid down in the interval between the end of the Pennsylvanian and early Cretaceous time. It is now evident that an important basin of salt deposition existed in the Arkansas-Louisiana-Texas area, but it is still an open question whether this salt basin was contemporaneous and continuous with the even larger Gulf Coast salt basin extending from Mississippi to Mexico. The accompanying columnar section (Fig. 1) shows the producing zones and names that have been applied to the several subsurface formations, most of which have no outcrop equivalents. This is for the convenience of readers unfamiliar with recent developments, but the correlations and nomenclature cannot yet be considered final. These formations will be discussed in more detail in various papers to be published in the near future.

Jan 1, 1938

By J. W. Rutter, K. T. Aust

In previous studies of grain boundary migration in zone-refined lead, the authors used bicrystal specimens consisting of a striated crystal which was grown from the melt, and an adjacent striation-free crystal, introduced by artificial nucleation and growth.1 While this method permits the study of the motion of individual grain boundaries, it does not provide control of the relative orientations of the grains. The present note will describe a technique for controlling the orientations of the two crystals in this type of specimen. The technique consists essentially of placing a striated crystal and a striation-free crystal of controlled orientations end-to-end in a graphite trough, then melting a short zone at the junction of the two crystals and allowing it to freeze to form the desired grain boundary. The apparatus used to carry out this process is illustrated in Fig. 1. It consists of a trough milled from high-purity graphite,with grooves in the underside for the placement of thermocouples. The graphite piece fans out on one end at the level of the bottom of the trough; the sides of the trough are completed in this region by the attachment of a mating plate with a slot cut at any desired angle to permit reorientation of the crystal placed at this end of the assembly. The joint between the crystals is made at or near the point where the slotted plate joins the rest of the trough. The thermocouple slots are deepened in this region so that the thermocouples are separated from the melt by only 1/32 in. of graphite. An induction heater, with suitable temperature control, is used to obtain the molten zone. The two single crystals used are first chemically polished in a solution consisting of eight parts glacial acetic acid and two parts 30 pct hydrogen peroxide. They are then placed in the trough with the ends to be joined at the position of the thermocouples. Next, cooling is applied to the two crystals by means of air

Jan 1, 1962

By F. J. Tuck

THE Hayden mill of the Ray Mines Division, Kennecott Copper Corporation, is now equipped with two 9 by 12-ft. rod mills having a daily capacity of 6000 tons of coarse-crushing plant product from the mine. These two mills crush a 3/4-in. product to approximately 19 per cent on 14 mesh, with only one pass through the mills. Each rod mill has taken the place of four sets of 42-in. Garfield rolls with their attendant screens, and is making a product for the fine-grinding department comparable to that formerly made by rolls in closed circuit with screens. The rod mills are lined with wave-type liners of white iron, varying in thickness from 2 to 3 in. The shell and end liners last approximately 600 to 700 clays. Manganese-steel lifter bars, 3 5/8 in. thick, are used, spaced about 11 in. apart, and they give a life of 350 to 450 clays. Fig. 1 shows the general design and thickness of the wave-type liners and lifter bars; 1 1/2 -in. liner bolts are used to fasten the lifter bars to the shell. The shell liners are held in place by the tapered lifter bars. A ¾-in. wood hacking is used between the shell and the liners. The rod-mill scoop has removable manganese-steel lips, which last 250 to 300 days. The scoop proper has shown some wear in spots; and these spots have been protected by rubber bolted over them. Water and milk of lime are added to the elevator feeding the mill, but not enough water to cause a pounding of the rods against the shell. Roughly, the water added amounts to 2.5 to 33 per cent of the ore. Addi-tional water is added to the mill discharge to facilitate distribution to the classifier bowls in the fine-grinding department.

Jan 1, 1938

By W. G. Pfann

WHEN a molten zone traverses a long, solid ingot in a level, open boat the ingot becomes tapered. While the taper may be slight after one zone pass, it can be appreciable after repeated zone passes, even to the extent of causing an overflow of matter at the end of the boat. It will be shown here that such matter transport by a molten zone arises from the volume change on melting and that it corresponds in magnitude and direction to the magnitude and sign of the volume change. It will be shown also that the mechanism of matter transport is basically similar to that of solute transport by a molten zone, which has been discussed elsewhere,1,2 and that the two processes can be described by similar equations. Finally it will be shown that matter transport can be prevented by inclining the ingot at a critical angle. Contraction on melting results in forward transport, that is, transport in the direction of zone travel; expansion on melting results in reverse transport. The way in which forward transport arises from the contraction on melting may be seen as follows: At the starting end of a solid horizontal ingot of uniform rectangular cross section of height h., form a molten zone of length 1, as shown in Fig. 1. The height h of the liquid will be h. where a is the ratio of density of solid to that of liquid. Advance the molten zone, at constant length, a distance dx. The volume of solid melted will be hdx; the volume of solid frozen will be Izdx, because the height of the freezing solid will tend to be equal to that of the liquid. The resultant change, dv, in liquid volume will be the difference in these quantities multiplied by the density ratio. Hence the following equation may be used for a zone at any distance x from the origin: which is valid in all but the last zone length in the

Jan 1, 1954

By I. R. Kramer

Single crystals of aluminum were pulled in tension in a solution of paraffin oil and stearic acid. The critical resolved shear stress did not change with the concentration of the stearic acid solution; however, the extents and slopes of Stages I and II were affected greatly. The observations lend evidence that the weakening effect of surface-active agents is controlled by the rate of desorption of the metal soap formed by the reaction of the surface-active agent and the metal surface. IT has been shown by various investigators1-" that surface-active agents markedly affect the mechanical properties of single crystals. (A surface-active agent, for the purpose of this report, is defined as a long-chain organic molecule which contains one or more polar groups. Usually, however, investigations have considered only molecules having one polar group.) In general, when single crystals are deformed in some solutions containing surface-active agents, the creep rate, Fig. 1, is increased and the yield strength is decreased. The fatigue strength has been reported to be affected also.ll Rehbinder and his asociatesl' explained the "weakening" effect of surface-active agents in terms of physical adsorption. They assumed that a large pressure was created in microcracks which existed on the surface of the crystal." Harper and Cottrell,' from their study of the effects of surface conditions, found that the deformation characteristics of zinc single crystals were not altered by a solution containing a surface-active agent unless the surface of the specimen had an oxidized surface. They concluded that the role of the polar molecule was to remove the strengthening effect of the oxide coating. Later, And-radeetBpresented additional evidence which appeared to agree with this conclusion. In contrast, Klinken-berg et al.7 reported data which confirmed the results of Rehbinder. Using zinc and cadmium crystals which had been cleaned by electrolytic polishing, a large increase in the creep rate was observed when Lle specimens were tested in a 1 pct oleic acid-paraffin oil solution. They also reported that the creep rate

Jan 1, 1962

Jan 1, 1927

By B. Welber, R. Webeler

A CCORDING to accepted theory, fatigue in A] metals is connected with the occurrence of local strain hardening even at applied stresses below the yield point as a consequence of stress concentrations created by the presence of structural inhomogeneities.1 It seemed possible, therefore, that

Jan 1, 1954

By G. V. Sullivan, B. E. Davis, T. O. Llewellyn

The Bureau of Mines, US Department of the Interior, conducted studies to recover phosphate from four dolomitic southern Florida deposits not currently mined. The samples contained 5.8-10.2% P205 and 1.7-4.8% MgO. Chemical analyses of sized fractions indicated that no pebble concentrate, +1.2 mm (+14 mesh) could be produced from these samples. A scheme was developed that consisted of desliming, grinding, scrubbing, and redesliming the ore to produce a flotation feed. Conventional one-step fatty acid fuel oil batch flotation tests on the samples resulted in concentrates containing 29.0-31.3% P205 at flotation recoveries ranging from 72.4 to 96.1% of the flotation feed. The MgO content of the concentrates ranged from 0.47 to 1.36%. Continuous flotation of the Manatee No. 2 sample indicated that commercial-grade phosphate concentrates analyzing 31.3% P205 and 0.55% MgO could be produced with a flotation recovery of 89.9%. The MgO content of concentrates obtained from the Manatee No. 1 and Hardee samples was 1.20 -1.36 %, respectively. Leaching with aqueous SO2 reduced the MgO content of these phosphate concentrates to 0.5 and 0.8%, but with a concomitant loss in phosphate recovery of about 10%.

Jan 1, 1985