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By Thomas V. Falkie

Of the various critics of federal energy and minerals policy we are hearing these days--and they are legion--few make their points more vividly than our fellow SME member and eloquent spokesman for the mineral industry. Mr. Eugene Guccione. In a moment of comparative mellowness. Mr. Guccione recently characterized Washington's time-honored legislative and bureaucratic machinery as a case of "...scientific illiterates asking the incompetents to do the unnecessary." I hope the prevailing industry view of government is not quite that harsh, and yet one cannot deny that government intervention is indeed pressing in on the mineral industry with increasing force. What is happening today in Washington and in state capitols will have enormous impact--both short and long term--on the future of coal and mineral production in the United States. Symptoms of this trend are everywhere. In the first place, there is a sentiment, widely held and still spreading, that the government must become involved-- that no matter what the problem, the solution lies in more government intervention. Free enterprise versus statist, reflex reaction organizations. When it cones to regulation in the resource field, there is too often a tendency to start out by assuming guilt on the part of the mineral industry. This can lead to laws governing mineral recovery that are more punitive than constructive...laws drawn up with little research into the scientific or economic considerations involved.

Jan 1, 1975

By Mahmoud A. Rabah

"In this work, metal values were prepared from used beverage cans. The cans are made of aluminum and minor alloying metals and printed with a multi-color printing ink. A method has been investigated to remove the printed coating using organic solvents or by sand blasting technique in a rotating drum. Metal values of the cleaned cans are prepared applying combined hydro and pyrometallurgical treatments. Factors affecting the efficiency of the suggested method have been studied.The results show that the extent of removal of the printing coating is successfully performed with recyclable methyl ethyl ketone I dimethyl formarnide mixture. With sand blasting, it proceeds regularly with the inner diameter, the rotation speed of the drum, the size of the sand grains and temperature. The removed coating is stripped with the same solvent. Metal alloy(s) are prepared in two ways. In the first way, the cans are pressed into solid blocks using hydraulic press before melting at temperatures up to 1000°C using borax-sodium chloride salt mixture as a flux. The quality of the metal obtained is a function of the salt and temperature. The slag so formed was leached with mineral acid solutions. In the second way, the used beverage cans are directly dissolved in mineral acids whereby different metal values are selectively precipitated. The undissolved part is fused with sodium carbonate at 800°C and processed in the same manner. Results were explained in the light of the thermodynamic properties of the species involved."

Jan 1, 2000

By W. C. Knopf, G. Samsel

For several years International Minerals & Chem-ical Corp. has used a radiation method to assay potassium content of products from potash and feldspar beneficiation. The procedure is rapid, accurate, and inexpensive and is easily handled, if necessary, by nontechnical personnel. Data are presented to show the accuracies that may be expected if the technique is used for control of pilot plants or large-scale plants. Natural potassium is composed of three isotopes —K, K and K. Five other isotopes, artificially produced, have been detected. In natural potassium only the K isotope, with a half life of 1.4x10 years, is radioactive. Its modes of decay are beta and gamma rays, positrons, and x-rays. Only the more abundant beta rays, however, are important in radiation measurements using geiger tubes. Barnes and Salley' measured radiation of potassium salts in solution in 1943. Gaudin and Parnell2 first reported the use of solid salts arranged in a vessel surrounding the ß counter in 1948. Later, Scheel used the method to assay potassium content of various crude and finished potash salts. Experimental: Dip-type Geiger-Muller tubes (TGC-5) supplied by Tracerlab Co. were used in all radiation counting measurements. The tube was encompassed by a glass container about M in. larger in diameter than the tube. This container, which served as a sample holder, was closed at the bottom with a rubber stopper to facilitate removing the samples. Samples were not weighed, but about 40 g of sample were needed for each test. Electrical impulses from the tube were counted on either a Tracerlab scaler or a rate meter. To obviate the need for constant attendance, preset features were incorporated into the scalers, so that at a predetermined time or count the units were automatically deactivated. When rate meters were used, counting rates were read directly from instrument or from a recorder used in conjunction with the rate meter. Each tube was calibrated, according to the manufacturer's instructions, to determine the correct operating voltage to insure reproducible results. A linear calibration plot of percent K2O vs counting rate was also obtained for each tube by recording the counting rate plus background count of several standards of different K2O content chemically analyzed by the chloroplatinate method.' These standards were of approximately the same particle size distribution as samples to be assayed. Specific background count caused by cosmic rays and other surrounding radiation was checked periodically by counting a sample of pure NaCl. Fig. 1 is a representative calibration plot. Assays were determined directly from the standard plot or calculated by subtracting the background count from the counting rate, then multiplying by the slope of the line. Chemical assays of the test samples were made by the Sherril method," a flame photometric technique, or the chloroplatinate method. Data: The radiation assay method has been used for three years by International Minerals & Chemical Corp. in the laboratory and in pilot plants processing ores containing potassium. These dry concentration plants process sylvinite and langbeinite ores at Carlsbad, N. M., and feldspar ores at Top-sham, Maine. Sylvinite ore is predominantly a mixture of syl-vite (impure KCl) and halite (impure NaCl). Contaminants include sulfates, such as langbeinite (2MgSO - K2SO4), kieserite (MgSO H2O), poly-halite (MgSO4.K2SO, 2CaSO, . 2H2O), and slimes. Langbeinite ore is predominantly langbeinite and halite with small amounts of sylvite, sulfates other than langbeinite, and slimes. Several variables, in addition to correct calibration and standardization of tubes, were found to be important in obtaining reproducible results. Particle size distribution of standard samples should be

Jan 1, 1959

Soon after the Rosebery concentrator commenced operations in 1936, an investigation was begun in an attempt to discover a substitute for cyanide in lead flotation. Cyanide is an excellent depressant for zinc and iron, but it also powerfully depresses the copper, silver and gold bearing minerals present in Rosebery ore, thus allowing them to pass through to the zinc concentrate or final residue where they are of little or no value.The investigation was not entirely successful, but it did indicate that sodium bisulphite or sodium sulphite could be used as a depressant for zinc without depressing the copper, silver and gold bearing minerals. The sulphites were, however, much inferior to cyanide as apyrite depressant.At about this time, I. W. Wark, using the captive bubble technique, had shown that, at the concentrations normally used, sodium aerofloat is not a promoter for pyrite or galena in alkaline solutions (see his book "Principles of Flotation", p. 188). Some preliminary tests on the production of a copper concentrate from Rosebery ore were therefore carried out using sodium sulphite as depressant and sodium aerofloat as promoter.The results of this work were promising but, since Rosebery ore usually carries only about 0·5% copper, there did not seem to be much incentive to carry the work further. With the outbreak of war, however, Australia became desperately short of copper and the relatively small amount in the ore. became of sufficient importance to...

Jan 1, 1952

By D. W. Mitchell

While pure magnesium does not corrode rapidly the presence of even very small quantities of certain other metals accelerates corrosion remarkably. Because magnesium is such an electropositive metal (E° = +2.34 volts)' the presence of substances that permit galvanic activity is extremely undesirable. It is stated that as little as 0.017 pct of iron in magnesium causes a marked increase in the corrosion rate.2 Magnesium and its alloys are commonly melted in iron or steel pots; consequently the commercial metal has the opportunity to pick up iron if it has that tendency. Quantitative data on the solubility of iron in magnesium are of practical as well as of academic interest. Some magnesium alloy castings tend to have large grain size unless suitable treatment is given to the liquid metal just prior to casting. One method of grain refinement consists of "superheating" the metal just prior to casting. "Superhcating" is heating to a temperature 100 to 200°C above the casting temperature and holding for a short period of time. Superheated metal has a much finer grain than unsuperheated metal. A satisfactory explanation of this phenomenon has not been forthcoming. One hypothesis attributes the grain refinement in the superheated metal to precipitation of some phase that is mis-cible at the temperature of superheat but not miscible just below the casting temperature and which is thought to provide nucleating centers for crystallization. This phase, if the foregoing hypothesis is correct, would probably be a metal or an intermetal-lic compound. Of the metals likely to be found in magnesium alloys, iron is one of the most likely candidates for the role of grain refiner for iron occurs in small quantities in all commercial magnesium and magnesium alloys. A. Beck³ states that magnesium, in either the liquid or the solid state, cannot dissolve iron and that iron exists as a finely divided suspension which does not settle out because of its extreme fineness. Beck also presents a micrograph showing a large iron dendrite in magnesium but does not comment on the crystallization of iron from a solution supposed to contain none. It is doubtful that dendrite formation from suspended iron -would be possible. This suspension theory is the basis of patents4 covering the removal of iron from magnesium by allowing the iron particles to act as nuclei for the formation of primary magnesium crystals which can be separated by segregation. Also covered by patents is the removal of iron by the addition of another metal to form an intermetallic compound with the iron which, because of its increased particle size, is able to settle out of the molten metal. Here, too, quantitative information on the extent of iron solubility in liquid magnesium is of more than theoretical interest. M. Hansen,5 in his critical collection of the data on binary alloys, states that iron is not soluble in liquid magnesium. W. R. D. Jones% ho studied the physical properties of low iron magnesium alloys observed a 57°

Jan 1, 1949

By I. Koliabina

In this paper, the results of mathematical modeling of casing pipes decontamination from radio-active new mineral forms directly in boreholes using hydrochloric and hydro-silicic-fluoric acids are presented. Modeling for highly and low radioactive coatings on the walls of casing pipes of Anastasievka oil-and-gas deposit was performed using GEMS software, based on the method of Gibbs energy minimization. Calculations have shown that thorianite and goethite, that are present in low-active crusts, detected in casing pipes uplifted from comparatively low depths, are well dissolved in hydrochloric acid, but radiobarite is almost insoluble. For the same acid concentrations, almost all radiobarite of high-active coatings detected in pipes uplifted from considerable depth is dissolved. To evaluate the possibility of decontamination of pipes from radiobarite of low-active coatings, modeling of crust dissolution under the action of H2SiF6 has been performed. The results have shown that for acid concentrations of more than 13 % almost all Ra and Ba are dissolved while all iron and thorium remains in goethite-thorianite solid solution. For the same acid concentration, almost all radiobarite from high-active coatings is dissolved. Therefore, no reagent allows decontamination of pipes from coatings of both types. It seems that successive or simultaneous use of both reagents (HCl and H2SiF6) in certain ratio is required. To clarify this issue, further experimental and model investigations are necessary. The issue of decontamination of casing pipes from galena that is present in high-active crusts also needs to be clarified.

Jan 1, 2005

By D. Nilsson, B. Aaro

To find out if there are any potential savings in "in-the-wall haulage for open pits," the Swedish companies ASEA and Kiruna-Truck in 1984 gave us financial support to study this solution in more detail. In the study, the use of in-the-wall haulage was studied for three hypothetical open pits with different sizes and shapes. Annual ore production rates also varied. A part of this thorough study was published by the Swedish Mining Research Foundation (see Report F 8444, "The Use of Electric Trucks and In-the-Wall Haulage in Open-Pit Mining," in Swedish with an English Summary). Although in-the-wall haulage is of interest in some open pits, the local terrain is important for profitability. The authors do not think in-the-wall haulage is of any major interest for the mining industry. The following is a summary of some of the author's findings. To place the haul road in the wall is not of interest in open pits with declining metal contents in the bedrock. In such mines, the volumes from the haul roads will not yield revenues. The cost per m3 for an underground haul road is much higher than for a haul road in the pit. This means that it is only of interest to place the haul road in the wall when mining gets deeper than about 50 m (165 ft). In-the-wall haul roads will reduce flexibility in the pit, and it will make necessary the use of smaller equipment with lower productivity and higher costs per ton. As Hustrulid, et al. show (Table 4), excavation savings of material hauled are very low, $0.10 to $0.25/t (0.09 to 0.27 per st). The extra operating cost, due to lower productive equipment, will normally be much higher and thus destroy the whole idea with in-the-wall haulage. If electric trucks are profitable for in-the-wall haulage, it is normally also profitable to use electric trolley assist for trucks on the haul road in the pit. But the profitability of using electric power is different in different countries, and depends on the relation between the cost for electric power and diesel fuel. In the US, diesel fuel is inexpensive compared with electricity, but in a country like Sweden, diesel fuel is much more expensive. In most open pits, the trucks have to move a considerable distange from the loader until they reach a final haul road in the wall. A trolley line along such temporary haul roads will be exposed to flyrock. It is normally less expensive to perform rock support from the open pit than from underground ramps in the wall. In Fig. 8, Hustrulid et al. gives the impression that the underground haul roads will be very close to each other. This is seldom the case. Figure 1 shows a haul road in the wall. The haul road passes through each cross-section only once. Arranging a reliable dewatering and rock support system from only one underground ramp is probably impossible. Many more drifts are therefore necessary. In our report, we also studied what would happen if the final pit slope is increased by 5°, using underground drifts in the wall. Our conclusion was that, the extra cost for drifts, rock support, pumps, etc. destroys the whole idea, and that it was better to accept a higher stripping ratio with the haul road in the pit and to use conventional low-cost open pit equipment. Finally, we think it is would be difficult to try to reduce the safety factor when determining the slope angle by moving the haul road in the wall. Minimizing the risk for pit wall collapse is also important with in-the-wall haulage, primarily because men and equipment will be working in the pit, but also to guarantee many accesses between the pit and the haul road in the wall.

Jan 1, 1990

By R. W. Hertzberg, R. W. Kraft

A study of the fracture behavior of unidirectwn-ally solidified Cu-Cr eutectic alloy was performed. Fractured whiskers, grain boundaries, and the interface between proeutectic Cr dendrites and the Cu matrix were the predominant failure initiation sites where grain size was larger. Strain induced void formation was restricted at lower solidification rates. This was attributed to a lack of adequate plastic constraint and a probable preferred orientation. A modification of the Crussard et al. model is presented to explain the appearance of "elongated dimples" on the shear fracture surface. A Cu-Cr alloy containing about 1.8 at. pct Cr solidifies by a eutectic reaction forming filamentary crystals of chromium within a continuous copper solid solution matrix.' Webb and Forgeng2 have shown by bend tests that the extracted chromium filaments, which are ordinarily curved and branched (due to random solidification), have the high strengths associated with whiskers. If an ingot of the eutectic alloy is unidirectionally solidified and appropriate control exercised over the thermal gradient, growth rate, and impurity level, the chromium fibers can be forced to solidify as fibers which are substantially parallel to the growth direction, Fig. 1. Uniaxial tensile tests on these straight chromium fibers extracted from controlled ingots3 have confirmed the earlier bend test results on curved fibers. Combining the facts that the strength and modulus of the chromium filaments are higher than the more ductile copper matrix and assuming that a "good bond" exists between the two phases, the Cu-Cr controlled eutectic system fulfills the requirements for effective fiber reinforcement of ductile matrices as established by studies on fiber glass reinforced plastics and other two-phase systems.4 Therefore, it was decided to study the fracture characteristics of morphologically simple specimens of chromium fiber reinforced copper (i.e., specimens of the controlled eutectic with substantially parallel reinforcing fibers) with the objective of establishing the dominant aspects of fracture. PREVIOUS WORK Comparatively little work has been done to understand the manner in which ductile alloys fail be- cause of the limited demand for this kind of information. Ordinarily ductility is specified for safety or similar reasons and when a part deforms plastically its useful life is terminated. In recent years, however, a number of investigators have begun to

Jan 1, 1963

By Paul A. Beck, M. N. Parthasarathi

The vecrystallization texture. formed by selective growth of random nuclei in an 80 pct volled 99.997 pct A1 crystal of initial orientation mear (123) (41.21 was found to consist of components related to the single-component rolling texture by 40 deg. rota-tiows around [111]axes. The relative-volume fractiovz of the various recrystallization-texture componezts may be accouzted for 012 the basis of the Lou) mobility of twist boundaries, if it is assumed that the mobility of the tilt boundaries also varies with their orientation. Similar results with a, aluminum-alloy cystal of the (110) [112] orientation, containing iron, silicon, and zinc, show that these solute contents do not impair the effectivezess of the oriented growth mechanism of re cry s-tallization- texture formation. In a previous investigation1,2 it was found that a sharp recrystallization texture is formed as a result of the oriented growth of random artificial nuclei in an aluminum crystal rolled to 80 pct RA, on the (110) plane in the [ 112] direction. Four recrystallization-texture components were found to occur, with orientations corresponding to 40-deg rotations around [111 1 axes of the deformation texture. Reorientations of this type were already found in earlier work,3,4 where the presence of random nuclei could be reasonably assumed, but was not rigorously documented. The same orientation relationship was found also by Lucke and Liebmann, who actually measured the orientation dependence of boundary-migration rates in the recrystallization of A1 crystals slightly deformed in tension.5,6 The occurrence in the recrystallization texture of only four of the eight crystallographically equivalent orientations of the type referred to above remained unexplained,1,2 although it was clearly not a result of the absence of suitable nuclei. Recently Burgers7 suggested that this effect may be due to the aniso-tropy of boundary mobility observed2'6; it was found that the recrystallized grains of the 40-deg [111]-rotated type grow much faster in directions perpendicular to the [ 111] they have in common with the matrix than parallel to this direction, i.e., the tilt boundaries have much higher mobility than the twist boundaries. The four orientations corresponding to

Jan 1, 1962

By H. C. Chang, N. J. Grant

REEP studies and measurements in most in-V> stances are based on a relatively gross gage length. Even in some recent theoretical studies on the mechanism of creep, changes were followed by means of X-rays and metallography without regard for the behavior of the individual grains and grain boundaries.'" Analytical studies of creep have frequently indicated that more than one competing process is operative and that the ultimate creep performance depends on the effects of temperature, time, and strain rate as well as grain size.'-" he grains and grain boundaries are known to respond differently to these variables but the extent of the response is still little known, especially in poly-crystalline materials where the relative orientations of grains and grain boundaries are important. This paper reports some experimental observations of the behavior of the grain boundaries and their effect on the deformation in the grains. High purity aluminum was used to avoid complications of aging reactions, second phase, inclusions, etc. Experimental Procedure A small vertical nichrome wound furnace was built to permit direct loading on the test specimen. This furnace is capable of operating up to about 1300°F with reasonable temperature distribution. A ground rectangular quartz window, 1.25x0.5 in., is imbedded in the external stainless steel tube to permit observations of the creep process with a microscope. An argon atmosphere ,was provided to prevent oxidation. The quartz window caused a temperature gradient between the back and front surfaces of the specimen of 15" at 700°F. The temperature gradient could be cut down to 3°F along the length of the specimen by adjusting shunts across the furnace windings. An ordinary metallurgical microscope with a working distance of 14 mm was rebuilt so that it could be moved in three mutual perpendicular directions. Visual examination could be made with either a 30X eyepiece or a 15X filar eyepiece. Using an objective of focal length 24.3 mm and a numerical aperture 0.20 a total magnification of 120X or 240X could be obtained. High purity aluminum rated at 99.995 pct was supplied by the Aluminum Co. of America as % in. then the gage portion was further machined to 3/16 in. diam. The ends were Y4 in. diam and threaded to fit available specimen holders. Two opposite flat surfaces of the gage portion were obtained by milling, giving final dimensions of the gage portion of 3/4x3/16x3/32 in. Machined specimens were first electropolished in Jacquet's solution.' Reference marks were produced by pressing a thin sewing needle into the surface of the specimen. The specimen was then annealed at 900°F for 24 hr and at 1150°F for 12 hr. Typical macrostructures of specimens treated in this manner are shown in Fig. 1. The range of the grain size was 1 to 5.5 mm (see Fig. l), but most of the grains were of 2.5 mm and went through the whole thickness of the specimen. The specimen was re-electropolished and etched electrolytically to reveal the grain boundaries. In order to reveal the orientation difference of the grains, etch pits were produced on the surface of the grains by etching in a mixture of hydrochloric and nitric acids (HC1, 45 pct; HNO,, 10 pct; H,O, 45 , by volume). The specimens were very carefully put into the holders and furnace; yet even with this care, fine slip lines were developed on the specimen surface.

Jan 1, 1953

By J. Groyecki, M. Markuszewicz, J. Lassota, A. Zawada

The ratio of stable to unstable inclusions was found to ploy an essential role in the process of sccorldar-y recrystatlizalion in Si-Fe. The analysis of the free energy of inclusions in the range of heat-treatment of individual inclusions to be predicted. The effects MnS. ns inslable inclusions. were investigated. TO secure a high induction, the secondary recryslulliztt-lion associated wilh the texture is necessary. To obtain a low core loss an additional refiuing in the solid state is required. It has been found that sulfur can be more easily removed in racunm than in hydrogen and thai this process was hindered by the prescrzce of INCLUSIONS play an essential role in the development of cube-on-edge texture in Si-Fe. Their function consists in restraining the growth of primary grains up to about 900°C and in passing subsequently into solution at higher temperatures. This process is accompanied by the selective growth of secondary grains with (110)[001] orientation. The general effect of inclusions depends on such factors as the type of impurities, their amount. dispersion and stability, the conditions of diffusion in the space of lattice of metal, and the reactions at the metal/gas interface. In recent years, some of these factors were the subject of a special investigation. A positive influence of Mns, siN,' and vN3 has been established. The quantity of impurities4 and their dispersion5 have been found to be of major importance. Attention was called to the vital importance of diffusion and the conditions under which the impurities are removed from metal., It has also been demonstrated that in Fe-Si alloys by the techniques of powder metallurgy a special opportunity exists to obtain the (110)[001] type texture. 6 The aim of this work was to conduct qualitative investigations on the influence of inclusion stability on the development of cube-on-edge texture in a metal containing approximately 3 pct Si. Experiments were carried out on cast alloys and on those manufactured by powder-metallurgy techniques. The results obtained from these experiments were utilized to explain the phenomena involved and to analyze the relationships between stable and unstable inclusions and the magnetic properties of alloys. EXPERIMENTS AND RESULTS The raw materials used in these experiments were the powder of carbonyl iron with the analysis (in pct) 0.044 C, 0.01 Mn, 0.005 Si, 0.009 P, 0.002 S, traces of Cu, 0.06 Ni, 0.0015 Al, 0.03 Cr, 0.02 Mo, 0.01 Ti, 0.002 Co, traces of Pb, and the powder of silicon containing 94.14 Si, 0.003 S, 0.048 C. The powders were ground and mechanically mixed in 100-g batches. and then pressed at 9 tons per sq cm into 74 by 24 by 8 mm blocks. Sintering was carried out at 1100°C for 12 hr in vacuum (2 x lo-' Tr) or in hydrogen. In this instance the material was heated slowly and subjected to prolonged soaking at 350°, 650°, and 750 2C, respectively, to secure reduction of ferro-oxides. This was checked by making measurements of the dew point, which was found to change from -15" to -35°C after reduction. The compacts after sintering were hot-rolled to 2.4 mm, annealed at 800 C, and finally cold-reduced to 0.35 mm with intermediate annealing at 800°C at a gage of about 0.8 mm. Impurities were added in the powdered form and mixed with iron and silicon powders. Sulfur in the elemental state, electrolytic manganese, and pure aluminum oxide were employed. Besides, to obtain a material with low contents of impurities, especially

Jan 1, 1967

By D. L. Garthwaite, F. M. Stewart, F. K. Krebill

Pressure has been maintained in the Elk Basin Ten-deep reservoir since the initiation of inert gas injection in Sept., 1949. Oil is being produced under conditions favorable for gravity drainage, including high angle of dip, appreciable structural closure, and fairly good per~neability. Results being obtained are high per cent recovery of oil-in-place, sustained field productivity, reduced operating problems, and recovery of plant products. The high recovery has been calculated by alpplication of the gravity drainage theory described in an earlier AIME paper.' It is also confirmed from field performance by comparing nil recovery to date with gas cap spuce voided. GENERAL INFORMATION The Elk Basin field lies in Park County, Wyo., and Carbon County, Mont., approximately 50 miles east of Yellowstone Park. Located at the northern end of the Big Horn Basin. the field is situated on an elongated asymmetrical anticline (Fig. 1). The pressure maintenance project covered by this paper involves the Embar-Tensleep reservoir in this multi-pay field. Discovered in Nov., 1942, it has a proved productive area of over 6,300 acres. It consists of the 210-ft thick Tensleep sandstone of Pennsylvanian Age overlain by 40 ft of Embar dolomite of Permian Age. The two formations apparently are in communication with each other and are produced as a common source of supply. As 98 per cent of the reserves are contained in the Tensleep sandFtone, in this paper the Embar-Tensleep reservoir will he called simply the Tensleep. The reservoir is found at an average depth of 4,900 it, is approximately 7 miles long and 2 miles wide, and has a maximum oil productive closure of 2,330 ft. The strata dip an average of 21" on the west flank and 45" on the east. There are presently 132 Tensleep wells in the field drilled on 40-acre spacing; of these, 17 are shut in because of high gas-oil ratio (GOR) and eight are gas injection wells. Rock characteristics and related information for the pay section follow: Porosity, avg 10.7 per cent Permeability (air) from cores, avg 118 mds Permeability from PI'S 91 mds Connate water, avg 8 per cent Initial pressure (-400 ft) 2,234 psia Pressure April 1954 (-400 ft) 1.327 psia At high structural positions much of the better sandstone has connate water content of only 2 to 5 per cent as indicated by the coring of wells with oil in nearby Tensleep fields. In special imbibition tests, samples readily imbibed oil but repelled water. In tests on crushed samples, the sand grains rapidly settled in oil and carbon tetrachloride but formed a stable unsinking floc in water. This information indicates that the Tensleep sand is preferentially oil wet. The oil produced averages 29' API gravity and has a high sulfur content. Extensive sampling and testing have established the fact that characteristics of reservoir oil in this field vary greatly with structure, see Fig. 2. Additional detail on the variation of oil characteristics with structure at Elk Basin may be found in Reference 2. At original reservoir pressure the oil was undersatu-rated with gas, the bubble point being 1,250 psi at the crest but only 500 psi at the lowest elevation sampled. As noted on Fig. 2, other fluid properties—reservoir volume factor. solution ratio, gravity, viscosity, and hydrogen sulfide content—likewise vary greatly. These variations complicate mathematical analysis, for it is necessary to average these characteristics in order to enter them into reservoir engineering expressions. To further complicate analysis, sand-face pressure also varies greatly because of the increase in fluid head down structure. As an approximation, average properties under initial conditions may be read from Fig. 2 at the -450-ft elevation.

Jan 1, 1956

By S. S. Cole, H. Sigurdson

The melting points of mixtures of titanium dioxide and other titanates have been reported to a limited extent as binary systems and some results have been reported in conjunction with silicon dioxide. The limited data indicated that a low melting zone might exist in a ternary or quarternary system of CaO-MgO-TiO2-Al2O3, since the eutectics reported in the binary systems of MgO.TiO2-TiO2, Al2O3TiO2-TiO2 and CaO.TiO2-TiO2 were of about equivalent composition of TiO2. The importance of a low melting region with a high titanium oxide value in the developing of high titanium slags is fully appreciated by metallurgists. A comprehensive study was undertaken to establish basic information on low melting titanate mixtures. Compounds in the System CaO-MgO-TiO2 -Al2O3 Preparation of the titanates of CaO, MgO and Al2O3 confirmed reported data that the following compounds could be formed under oxidizing conditions in solid state reactions: CaO.TiO2, 2MgO.TiO2, MgO.TiO2, MgO-2TiO2 and Al2O3.TiO2. Under oxidizing conditions it was not possible to react MgO with TiO2 in mol ratios higher than 1:2 without having unreacted TiO2 in the product, nor was it possible to form calcium or aluminum titanates with a higher mol ratio of CaO and A12O3 to TiO2 than 1:1. By fusing mixtures of Al2O3-TiO2 and MgO-2TiO2 together a series of solid solution products were obtained, which showed an MgO-2TiO2 X ray diffraction pattern shifted to smaller inter-planar spacings. Range of Investigation Data in the literature1 indicated that these titanates had melting points which ranged from 1645 to 1860°C. Since the purpose of the study was primarily to provide useful data for smelting titaniferous ores, the work was restricted to the zone of the system which would include the crystalline phases present in the slags. The explored limits were bounded by CaO.-TiO2-MgO.TiO2-TiO2in the base plane. The system was extended to a fourth component Al2O3-TiO2 since many titaniferous ores contain appreciable amounts of A12O3. In the quarternary system CaO-TiO2-MgOTiO2-TiO2-Al2O3TiO2, a tetrahedron was used to represent graphically the components, with one component at each point of the tetrahedron. In the base plane, mixtures were pre- pared to represent fairly uniform changes of composition over the desired range expressed on a mol percent basis. Al2O3-TiO2 was brought into the system in increments of 10 mol pct up to 40 pct. Mixtures were then made up for each of the Al2O3-TiO2 planes. The ranges employed were then represented by five planes cutting the tetrahedron at 10 mol pct Al2O3-TiO2 intervals. Choice of Equipment Although it was necessary for all smelting work to be done in a strongly reducing atmosphere, it was decided that all melting point determinations should be done under oxidizing conditions. This decision was prompted by the fact that TiO2 reduced to lower oxides in a reducing atmosphere with consequent changes in melting points. The use of a micropyrometer and a platinum strip furnace for work of this type is adequately described in the literature.2 With modifications, equipment was selected which provided a fairly rapid method of determining melting points of refractory oxides. The final assembly, which was used, consisted of a platinum strip furnace and a Leeds and Northrup disappearing filament optical pyrometer attached to a special telescope which magnified the sample about 20 diam. The furnace assembly consisted of a platinum strip 0.005 X 0.3 X 2.2 in. mounted on brass posts on a refractory base. This was enclosed in a black steel shell which had a 2-in. opening at the top for purposes of sighting the telescope. The platinum strip was in series with two 0.04 ohm nichrome resistors connected to the secondary of a 2 kw transformer which supplied 17 volts. The current to the primary was varied

Jan 1, 1950

By Paul A. Beck, John Towers, W. D. Manly

Recent work on grain growth in high purity aluminum and in a solid solution type alloy of aluminum and magnesium1 showed that the isothermal increase of the average grain diameter D with time follows the equation D = K(tg + A)2 Eq 1 Here tg is that portion of the total annealing time 1, which is available for grain growth, that is the annealing time less the time necessary for complete recrystallization. The parameters A and n depend only on the temperature. A has the dimension of time, and is usually of the same order of magnitude as the time for recrystallization: R. In some instances R may be substituted for A in Eq I. This is the case for example at long periods of annealing or at high temperatures, where both A and R become small in comparison with t. In such instances Eq I is simplified to D = K, tn Eq 2 For high purity aluminum the exponent n increases in the ratio of about I to 5 in. the temperature range of 350' to 6w°C. 70-30 brass has been long known to exhibit grain growth of the continuous type, such as occurs in pure metals. For this reason, it was of interest to determine whether grain growth in brass also follows Eq I and 2 as it does in aluminum. Isotherma1 grain growth data for 70-30 brass were published in recent years by R. S. French2 and by H. L. Walker.' Fig I shows a log D vs. log t plot of French's data, together with the 500, 600 and 700°C data by Walker for 42.8 pct reduction by rolling. In such a log D vs. log t plot Eq 2 corresponds to a straight line with a slope of n. As seen in Fig I, the data of French and the 600°C data of Walker can be represented by straight lines. However, the 500 and 7c0°C data of Walker give curved lines and the average slope of his 500°C line is very different from the slope of the line representing French's data for the same temperature. Furthermore the curvature of the 700°C line suggests a tendency for grain growth to stop after 8 hr. If confirmed, this would constitute a definite deviation from Eq 2, not explainable on the basis of the specimen thickness effect found in high purity aluminum.' Walker's specimens were 0.125 in., or 3.18 mm thick, while the deviation occurs at a grain size of approximately 0.4 mm. A further point of divergence arose recently, when J. E. Burke suggested4 on the basis of Walker's data, that, instead of Eq 2, grain growth in 70-30 brass follows the equation D - D, = K . tgn Eq 3 Here D, is the grain size as recrystallized at the temperature in question. Although it was possible to show5 that, for pure aluminum, for which isothermal grain growth has been carefully investigated, Eq 3 is incompatible with the experimental facts, the situation remained somewhat obscure with respect to 70-30 brass. In view of the discrepancies between the published data on brass from different

Jan 1, 1949

By John Towers, Paul A. Beck, W. D. Manly

Recent work on grain growth in high purity aluminum and in a solid solution type alloy of aluminum and magnesium1 showed that the isothermal increase of the average grain diameter D with time follows the equation D = K(tg + A)2 Eq 1 Here tg is that portion of the total annealing time 1, which is available for grain growth, that is the annealing time less the time necessary for complete recrystallization. The parameters A and n depend only on the temperature. A has the dimension of time, and is usually of the same order of magnitude as the time for recrystallization: R. In some instances R may be substituted for A in Eq I. This is the case for example at long periods of annealing or at high temperatures, where both A and R become small in comparison with t. In such instances Eq I is simplified to D = K, tn Eq 2 For high purity aluminum the exponent n increases in the ratio of about I to 5 in. the temperature range of 350' to 6w°C. 70-30 brass has been long known to exhibit grain growth of the continuous type, such as occurs in pure metals. For this reason, it was of interest to determine whether grain growth in brass also follows Eq I and 2 as it does in aluminum. Isotherma1 grain growth data for 70-30 brass were published in recent years by R. S. French2 and by H. L. Walker.' Fig I shows a log D vs. log t plot of French's data, together with the 500, 600 and 700°C data by Walker for 42.8 pct reduction by rolling. In such a log D vs. log t plot Eq 2 corresponds to a straight line with a slope of n. As seen in Fig I, the data of French and the 600°C data of Walker can be represented by straight lines. However, the 500 and 7c0°C data of Walker give curved lines and the average slope of his 500°C line is very different from the slope of the line representing French's data for the same temperature. Furthermore the curvature of the 700°C line suggests a tendency for grain growth to stop after 8 hr. If confirmed, this would constitute a definite deviation from Eq 2, not explainable on the basis of the specimen thickness effect found in high purity aluminum.' Walker's specimens were 0.125 in., or 3.18 mm thick, while the deviation occurs at a grain size of approximately 0.4 mm. A further point of divergence arose recently, when J. E. Burke suggested4 on the basis of Walker's data, that, instead of Eq 2, grain growth in 70-30 brass follows the equation D - D, = K . tgn Eq 3 Here D, is the grain size as recrystallized at the temperature in question. Although it was possible to show5 that, for pure aluminum, for which isothermal grain growth has been carefully investigated, Eq 3 is incompatible with the experimental facts, the situation remained somewhat obscure with respect to 70-30 brass. In view of the discrepancies between the published data on brass from different

Jan 1, 1949

By C. N. J. Wagner, E. N. Aqua

Dilute Fe-Si alloys (0 to 5 wt pet Si) were cold-worked by making filings at room temperatuve. The analysis of the broadening of the X-vay powdev pattern peaks yields anisotropic particle sizes normal to the (110), (100), and (112) planes which are a consequence of deformation faults (probability a) and twin faults (probability p). The combined fault probability (1.5a +ß) increases from 0.01 in pure iron to 0.02 in Fe-5 pct Si. The root mean square stvains vary with crystallographic ovientation due to elastic anisotropy of the alloys, and increase from about 0.0035 in pure iron to 0.005 in Fe-5 pct Si measured in the [100] direction. Assuming that deformation and twin faults occur with equal probability, the X-ray data would imply that the stacking-fault energy does not change upon alloying. THE crystallographic aspects of the plastic deformation of dilute Fe-Si alloys has been studied many times since the observation of glide band structures by Barrett et a1.l These glide bands were much straighter than the wavy bands observed by Gough2 in unalloyed iron nearly 40 years ago. This difference in the morphology of the slip band structure has been verified many times, most recently by replication electron microscopy3 and dislocation etch-pitting methods.4,5 These observed differences in deformation behavior have been considered to result from the degree of cross slip that occurs in pure iron and in the Si-Fe alloys. The lowered tendency for cross slip would result from a lowering of the stacking-fault energy of iron by the silicon alloying addition. Experimental evidence for this lowered stacking-fault energy in the Si-Fe alloys, obtained with transmission electron microscopy, is the observation of dissociated dislocations in Fe-6 pct si6 and Fe-3 pct Si alloys,7 and the observation of sharply defined cellular substructures in Fe-3 pct si6,7 compared to the more diffuse substructure in zone-refined iron.' The activation energy for recovery of cold work is greater in the Si-Fe alloys than it is in pure iron, indicating that cross slip has become a more difficult process.9 The purpose of this investigation is to determine the change in stacking-fault probability from the broadening of powder pattern peaks in dilute silicon-in-iron solid solutions, when cold-worked at room temperature. The knowledge of the stacking-fault probability and the dislocation density, both of which can be deduced from line-broadening analysis of two orders of reflections from (110), (200), and (112) planes, will permit us to calculate the change in stacking-fault energy upon alloying silicon into iron. Previous X-ray investigation of cold-rolled Fe-5 wt pct Si (100)[001 ] single crystals did not reveal any line broadening, whereas cold-rolled Fe-3.1 wt pct Si (001) [110] and (001)[100] single crystals10 showed line bro2dening as a consequence of small particle sizes (-200A) and root mean square strains (-0.25 pct), which are comparable to those found in cold-worked iron filings.11 EXPERIMENTAL PROCEDURE A series of five Fe-Si alloys containing nominally 1 to 5 wt pct Si and pure iron were cold-worked by making filings at room temperature. The actual silicon content deviated at the most by +0.1 pct which is of no significance in the present study. The carbon contents of these materials were less than 0.02 pct. The X-ray diffraction patterns were measured with molybdenum, cobalt, and iron radiation using a GE and a Philips diffractometer. The (110)-(220), (200)-(400), and (112)-(224) pairs of reflections were

Jan 1, 1968

Branch Minutes of the General Meeting held at President Steyn Gold Mine canteen on Wednesday, 10th May, 1978, at 4.00 p.m. Erratum We apologize to Mr J. G. Taylor for the error in one of his qualifications. Bio-engineering monograph The selection of papers presented at the International Bio-engineering Conference at the University of Cape Town organized by the South African Institution of Mechanical Engineers and held in April 1977, and which are appearing in The South African Mechanic al Engineer during April to June this year, will shortly be available in book form. Mathematics The Institute of Mathematics and Its Applications is planning the following conferences and symposia: The Nand F Proposals in Relation to Mathematics, 1st July, 1978: London School of Pharmacy. NIM reports Report no. 1917 The instrumental neutron-activation analysis of granites from the Bushveld Complex. (31st Mar., 1978.) Report no. 1951 Potentialities and limitations of four-parameter equations for the correlation of formation constants of metal-ion complexes in aqueous solution.(15th May, 1978.) Report no. 1963 An evaluation of the methods used at the National Institute for Metallurgy for the analysis of base-metal concentrates. (28th Apr., 1978.) Report no. 1964 The separation, by anion exchange, of noble metals on substituted cellulose. (28th Apr., 1978.) Guide To The Preparation Of Papers For Publication In The Journal Of The South African Institute Of Mining And Metallurgy The following notes have been compiled to assist authors in the preparation of papers for presentation to the Institute and for publication in the Journal.

Jan 1, 1978

By Richard Pearce

In the treatment of auriferous copper containing bismuth, I have recently observed a small quantity of a grayish-white alloy, which on examination, proved to be Bi containing in solution, as it were, a crystalline alloy of Bi and Au. This compound makes its appearance on the surface of the auriferous Cu in small globules as the latter cools. These globules are rapidly attacked by nitric acid, and fine needleshaped crystals of Bi and Au separate out. They arc insoluble even in strong nitric acid. On examination, the crystals mere found to contain : Gold, 69.94 per cent.; silver, 0.63 per cent. ; bismuth, 29.43 per cent. (No. I).* The residue is very fusible, and at a temperature considerably below its melting-point it oxidizes rapidly, changing from its original gray color to a greenish-yellow (No. 2). On melting in a crucible under flux, a bronze-colored alloy is formed that has the specific gravity 15.47—somewhat higher than the calculated specific gravity of a simple mixture of the two metals in the proportions named. Alloys of Gold and Silver.—In following out my investigations by repeated examinations of this alloy formed at different times, I found that, in dissolving a miscellaneous lot of the alloy in nitric acid, some gold-yellow crystals were formed, which I succeeded in separating from the BiAu alloy by washing. These yellow crystals, under the microscope, showed distinct, regular, octahedral faces, and on examination they were found to be a crystalline alloy of Au and

Jan 1, 1885

By A. Hayatdavoudi, E. Apande

Introduction Troublesome shales have plagued the petroleum industry for more than 50 years. Unstable boreholes have been experienced when drilled into shale formations; sane have been studied almost at the beginning of rotary drilling. A little progress has been made since then, but much is still to be learned. No simple solution exists so far, but good drilling practices combined with good mud practices have been helpful. It is well known that shales in general have a strong affinity for water, and when water is adsorbed, the stability of the shale section of a well is reduced; cohesive strength will be re- bed, properties will be altered and shale will generally expand and/or crumble. The amount of water a shale will adsorb depends on the characteristics of its clay mineral and the ionic concentration of surrounding fluid. Fluid loss and the resulting hydration of an unstable formation can lead to serious downhole problems. The rate of fluid loss depends greatly on the permeability of the deposited cake. In impermeable formations, however, there is no loss of fluid into the formation. As such, shale, because of its very low porosity and almost no permeability, could be termed impermeable. Yet there is strong evidence that shale surfaces are wetted by an invasion of fluid into the formation through microfractures and jointed planes. It is this wetting that causes the shales to swell and slough into the hole, resulting in problems such as increased mud volume and treating costs, bridges and fill-up, stuck pipe, overgauge hole, poor cement jobs and increased cement requirements, and logging and completion difficulties. Drilling operations have been defeated by severe shale problems, resulting in & hole being plugged and abandoned after several weeks of drilling. Shales are we1l known as being difficult and costly to drill. Numerous fishing jobs have plagued drilling operations, and the cost of reaming tight holes ad weighting up the drilling mud to control shale sloughing has been high. The concept of controlling water loss to stop sloughing was introduced in the 1920's. It was known-then that calcium in fresh water re- strains clay £ran excessive swelling (theory of osmosis) . This reinforced the belief that calcium-based muds such as lime, gypsum and calcium chloride should minimize hydration of clays. Lime muds were then introduced for this purpose and others in the 1930-1940 decade1. They were used for shale inhibition but were not effective. In an attempt to improve them, a special calcium-type mud beam popular during the 1950's. Hole enlargement continued and they too were considered ineffective. During & early 1960qs, papers were published claiming that shale swelling could be prevented by using high concentrations of chemical thinner called Chrane Lignosulfonate1. This began the era of highly treated lignosulfote muds. Unfortunately, the hole enlargement problem continued. During & mid-1960’s, oil based muds were used for the purpose of inhibition of shales. Not until 1966 did Mondshine2 suggest that the water phase be saturated with calcium chloride. The cost of using oil based mud was considered by most operators not worth the additional hole stability. The potassium chloride-polymer muds were also used in many fields in the United States and western Canada. The use of these muds has been claimed to prevent clay swelling by inhibition and encapsulation in sane areas of western Canada. They are also expensive and their ueneral application is still experimental. To reduce filtrate loss when sloughing shale becomes a problem during drilling is a reasonable practice. This study will investigate the use of cationic organic additives to mud to form a protective barrier between the shale - which are primarily composed of clays - and water that will keep water from entering the microfractures and will also prevent them from hydrating. In so doing, an understanding of modern clay chemistry and & dispersive properties of cationic additives in water based systems will be our most valuable tools. This study will also present and solve a mathematical model for simulating cation transport phenomena in fractured shales using the Framdlich equilibrium adsorption isotherm. The studies will analyze wellbore failure and stability as affected by cationic organic material.

Jan 1, 1986

By R. E. Somers

Discussion of the paper of R. E. SOMERS, presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 101, May, 1915, pp. 957 to 996. A. C. LAWSON, Berkeley, Cal.-One point to which Mr. Graton (in summarizing the paper for us) called attention is that the author had not explained why some copper was fixed in the zone of oxidation. I recollect very well puzzling over that question at Ely, Nev., some years ago. Mr. Sales, in his paper on Butte,1 suggests the explanation. It is clue according to him to the paucity of pyrite in the primary ore. Where there is abundant pyrite sufficient sulphuric acid is formed by oxidation to take all the copper into solution and carry it to lower levels; but where the pyrite is scant so that insufficient sulphuric acid is formed, some of the copper is carbonated and so fixed in the gossan. The hypothesis, or some modification of it, as for example the combination of the sulphuric acid with lime, would appear to explain satisfactorily the fixation of the copper in the gossan as carbonate. I have, however, had no occasion in recent years to study the phenomenon. L. C. GRATON, Cambridge, Mass.-As I remember, the rocks in which the chrysocolla occurs in the Burro Mountains are both silicified and kaolinized. It seems probable that in surroundings deficient in carbon dioxide, complete oxidation of chalcocite may yield chrysocolla up to a maximum of half the copper in the chalcocite; while in rocks, like garnet contact zones and certain easily decomposable porphyries, surface decomposition appears often to yield silica in the necessary form to convert the copper of primary sulphides into chrysocolla immediately and directly upon oxidation.

Jan 12, 1915