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By Carl Beal

Introduction. DURING the latter part of 1915 and the first half of 1916, the writer held the position of geologist in connection with the conservation work instituted by the U. S. Bureau of Mines, on oil and gas land belonging to the Indians of the Five Civilized Tribes in Oklahoma. The duty of the geologist was to correlate formations containing oil, gas,-and water, and to determine the relations of these substances in the different formations so that the conservation agents might carry on their work most intelligently. On account of the rapid development of the Cushing field, which lies in the western part of the Creek Nation, much work was clone there by the inspection force. In the course of the geologic studies a large amount of information was collected, which, on analysis, has disclosed some interesting facts worthy of publication. The report, of which the following remarks are an abstract, has been prepared and submitted to the U. S. Geological Survey for publication. This report is now (June, 1917) in the press and will doubtless be issued in a few weeks. Methods Used In addition to the structure maps showing the folding of the Pawhuska limestone, which crops out in several places in the Coshing field, separate structure maps of the three most important productive sands-the Layton (Fig. 2), Wheeler, and Bartlesville-have been prepared. These structure maps, were prepared by obtaining the logs of nearly all the wells

Jan 8, 1917

By L. Seigle, R. Resnick

An inert-marker movement experiment indicates that the ratio of the intrinsic diffusion coefficients DC:DTa = 80:l in TaC at 2500°C. Measurements of the diffmion coefficient of carbon in nonstoichiometric TaC at temperatures from 1700° to 2700°C reveal that Dc increases with decreasing carbon content, but much less than expected from the probable change in vacancy concentration with carbon content. A diffusion process involving two simultaneously operating mechanisms is postulated, and shown to be theoretically feasible. The average value of the carbon diffusion coefficient is given by DC = 0.18 exp[(-85,000 ± 3000)/RT] sq cm per sec over the composition range 46 to 49.5 at. pct C. BECAUSE of their high melting points and hardness, the carbides of the IV, V, and VI group transition metals, along with those of uranium, have attracted considerable interest for applications at high temperatures. In these applications the reactivity of the materials is important, and, since rates of diffusion within the compounds influence reactivity, a knowledge of diffusion kinetics and mechanisms is desirable. While many investigations of the mechanical and electrical properties of these compounds have been made, only two fundamental investigations of diffusion in the carbides are known. Chubb, Getz, and Townleyl measured the diffusivity of carbon and uranium in UC, and Gel'd and Liubimov2 measured the diffusivity of carbon and niobium in NbC. This paper describes an investigation of the diffusion of carbon in tantalum monocarbide and, in particular, the influence of carbon deficiency on this process. Tantalum carbide melts at approximately 3800°C, which makes it one of the highest melting materials known. The compound exists over a rather wide range of carbon Content.3-7 At the peritectic temperature, 3240°C, the phase extends from about 36 to 50 at. pct C. Although the compound can exist with a substantial carbon deficiency, the high carbon phase boundary remains near the stoichiometric composition over the entire temperature range; i.e., no carbon excess is observed. The structure of TaC is the NaCl type wherein carbon atoms normally occupy the octahedral sites in a somewhat expanded fcc lattice of tantalum. Decrease of the lattice parameter with decreasing carbon suggests that the removal of carbon introduces octahedral vacancies into the lattice. I) EXPERIMENTAL DETAILS AND RESULTS Inert-Marker Experiments. In a compound such as TaC the interstitial element would be expected to diffuse more rapidly than the metal. This was confirmed by an inert-marker experiment, following Srnigelskas and irkeendall.8 Ideally, the markers should be placed at the interface between a slab of low-carbon TaC and graphite, and their movement during subsequent inter-diffusion measured. Unfortunately, no solid could be found which is unreactive in contact with carbon at the high temperatures employed in these experiments. In order to circumvent this problem, a specimen was designed in which the markers consisted of several small canals running just below the surface of a tantalum slab. This specimen was prepared by machining grooves on the surface of the tantalum slab and then diffusion-bonding a thin plate of tantalum to the slab over the grooves. The surface of the plate was then ground down until the distance between the canals and surface was as small as possible (about 0.01 cm). Thus, the canals would lie entirely within the TaC phase after a short period of diffusion. The diffusion anneal consisted of immersing the metal sample in high-purity graphite powder and heating for approximately 10 hr at 2500°C under vacuum. At this temperature, the vapor pressure is sufficiently high and the transfer of carbon from graphite sufficiently rapid to allow the surface of the diffusion sample to attain the stoichiometric carbon concentration very quickly. Conclusions regarding the relative diffusion rates of carbon and tantalum in the compound layers (TaC and Ta2C) can be drawn from the location of the canals after the diffusion anneals. If the growth of the layers is governed mainly by the diffusion of carbon, as expected, the canals should remain close to the sample surface. If the diffusion of tantalum contributes appreciably to formation of the compound layers, the distance from the markers (canals) to the surface should increase. Fig. 1 shows, diagrammatically, the appearance of the specimens after diffusion, and Table I presents the depth below the surface at which the

Jan 1, 1967

By G. W. H. Norman

INTEREST in the mineral possibilities (gold, copper) of northern Quebec, north of the Quebec-Cochrane branch of the Canadian National railway, has centred for many years in the Chibougamau district (see Figure 1). Since 1934, however, promising gold discoveries in the Rose Lake-Florence River section, 115 miles southwest of Chibougamau lake, have widened the interest, and prospectors have examined other parts of the country between Chibougamau lake and Bell river and the surrounding districts. The object of this paper is to !resent an outline of the geology, and to describe the mineral deposits, o part of this region, or, more specifically, of the part embraced by the Opawica-Chibougamau and Waswanipi map-areas(l), which include the districts about Chibougamau lake and Rose lake-Florence river, where mineral deposits are now in course of development either by surface or underground work. Early discoveries, developments, and explorations in the Chibougamau district are well summarized in the report of the Chibougamau Commission, published in 1911(2). The Commission discredited previous optimistic accounts of mineral discoveries in the area, made initially in 1903, but at the same time they expressed the opinion that, from a geological standpoint, the district promised a reward to diligent and intelligent prospecting. Their general conclusion-that prospecting in the area was not then (1911) commercially advisable in view of its inaccessibility and other handicaps shifted interest from the district until, some years later, valuable discoveries were made in the Rouyn area, and aircraft widened the field of successful exploration. During the past ten years or so, considerable energy has been spent in promoting the development of the district. The net result has been the discovery of a number of prospects, the majority of which have been explored only by trenching and, in most cases, diamond drilling.

Jan 1, 1936

By Y. C. Liu, G. A. Alers

measurements of the anisotropy in Young's modulus produced in copper by rolling 95 pct reduction in thickness below room temperature have been carried out in order to study the dependence of the texture on rolling temperature. The results clearly show the transition from a copper-type texture to a brass-type texture as the temperature of rolling is lowered. The intermediate textures observed can be described very well as a simple mixture of the two terminal textures. These results cormbined with other texture measurements make possible afresh review of the experimental facts velating to rolling textures in fee metals and, as a consequence, a critical examination of the current theories is presented. PREVIOUS experiments have shown that the transition from the copper- to the brass-type rolling texture is clearly displayed and can be quantitatively analyzed by measurements of the anisotropy of Young's modulus.' Application of this method to the Cu-Zn alloy system showed that the description of the texture transition as a gradual rotation of the grains from the orientation characteristic of the copper texture to the {110}(112) texture of brass2 was inconsistent with the data. Instead, the data suggested that the texture within the transition region could be described as a simple mixture of the two terminal textures.5 Unfortunately, it was difficult to establish this point conclusively because of the inadequacy of corrections for the composition dependence of the single-crystal elastic constants. Since a rigorous establishment of the nature of this texture transition is essential to our understanding of the formation of rolling textures in fee metals, it is clearly important to undertake an investigation in which the composition dependence of the elastic constants would not enter. A suitable composition-independent texture transition is provided by the well-established variation in the rolling texture of copper with rolling temperature. This temperature-dependent texture transformation has been studied by smallman' in several fee alloys and by Müller5 and others"' in copper. They observed that the texture characteristic of copper rolled at room temperature changed to a brass-type texture when the rolling temperature was lowered to 77°K. Although it is not possible to decide unequivocally from the published pole figures whether or not the 77°K rolling texture of copper is entirely of the brass type,' this complication does not affect the main purpose of the present investigation. In addition to establishing the nature of the texture within the transition region, the modulus data should also provide a determination of the temperature at which the transition occurs as well as the temperature range over which the transition extends. This information when combined with the modulus data on Cu-Zn alloys would then provide a considerable body of new information on textures in fee metals. Since these modulus results and the data obtained from pole-figure studies must be internally consistent, it is appropriate to compile a brief summary of the experimental observations based on all available methods rather than on the pole-figure data alone as has been done in the past. The primary purpose of such a summary would be to yield a more precise definition of the experimental facts on the rolling textures of fee metals, and thus greatly facilitate our evaluation of various proposed theories in this field. The final section of this paper is devoted to this compilation of consistent, experimental facts and their application to the various theories. EXPERIMENTAL PROCEDURE Two 18-lb ingots of cathode copper of 99.99 pct purity were induction-melted under a nitrogen atmosphere in a graphite crucible and chill-cast into a steel mold. The ingots were repeatedly cold-rolled and annealed (I hr at 500°C) into slabs about 1 1/8 in. thick. Blocks 3 1/4 in. wide, 2 1/4 in. long, and 1.000 in. thick were machined from each slab. The rolling schedule used was the same as in the previous investigation1 and the final thickness of the sheet was 0.050 in. with a rolling reduction of thickness of 95 pct instead of 97.5 pct as in the previous work.' The compositions and temperatures of the cold baths used for the low-temperature rolling were as shown in Table I. After each pass the rolled strip was immediately immersed in the cold bath for about 1 min or until the bubbling of the bath had subsided. The modulus data were taken within 2 hr after the rolled strip was warmed to room temperature for the first time, so that effects due to recrystallization were minimized. The modulus specimens were in the shape of flat bars, 3 in. long, 4 in. wide, and 0.050 in. thick, cut with their long dimensions oriented at 15-deg intervals between the rolling direction and the transverse direction. The values of Young's modulus were deduced from measurements of the frequency at which these long narrow bars were set into longitudinal, resonant vibration as previously described.9 To excite the mechanical vibrations in the specimen, an electromagnetic drive similar to that employed by Thompson and lass" was used. The maximum in the amplitude of

Jan 1, 1968

By S. Brunauer

The hydration of portland cement is treated as a chemical reaction and the changes in matter, in energy and the rate of change of the process are discussed, Portland cement is a mixture of four major and at least as many important minor constituents. In the hydration process, the four major compounds (trical-cium silicate, dicalcium silicate, tricalcium alumi-nate and tetracalcium aluminoferrite), plus gypsum and water form five or six new compounds. In spite o the great complexity of the reaction, considerable progress has been made in its understanding, primarily with the help of such research tools as X-ray diffraction and electron microscopy. The rate of the reaction can be followed by direct and indirect methods of measurements. The effects o composition, particle size (or specific surface), temperature and water-cement ratio on the rates of hydration are discussed. The hydration of portland cement is a chemical reaction accompanied by such highly important physical phenomena as heat evolution, setting and hardening. It is a vast and complex subject, on which hundreds of papers have been published. At the time of the writing of this paper, in October 1962, a two-volume book, which alone contains dozens of papers pertaining to cement hydration appeared in print.' The present paper deals with a few aspects of this vast subject, and the selection was not easy. The work reported here deals with some of the most recent investigations in the field. In any chemical reaction, the physical chemist is primarily interested in three things: changes in matter, changes in energy and the rate of change of the process or the speed of the reaction. This is true also of the chemical reaction between portland cement and water, and all three aspects of the reaction will be discussed. These three aspects are of vital interest to the engineer as well. Portland cement is not a cementing material — the hydration products, the new materials which form in the reaction, have the cementing action. The energy changes manifest themselves in a considerable evolution of heat, which may be useful or harmful. It is useful, for example, in winter concreting, but in very large concrete structures like dams, a large evolution of heat, which cannot be easily dissipated, may produce distress in the structure. Primarily for such a purpose was the Type IV or low heat portland cement developed. The speed of the chemical reaction is important because it determines the time of setting and hardening. The initial reaction must be slow enough to permit placing of the concrete before setting occurs. On the other hand, after the placing of concrete it is often highly desirable to obtain as rapid chemical reaction as possible. For this purpose the Type 111 or high early strength portland cement was developed. CHANGES IN MATTER Portland Cement: In a basic investigation, before one begins to study a reaction, one either knows the quantities and compositions of the starting materials, the reactants, or one determines them. This is obvious; the chemist expresses the changes in matter that occur in a reaction by a chemical equation, which has the quantities and compositions of the reactants on the left side of the equation and the quantities and compositions of the reaction products on the right side. The first question is then what to put on the left side of the equation in the reaction between portland cement and water? It is not very easy to answer this question. Portland cement is not a single chemical compound but a mixture of many compounds. Four of these are considered the major compounds, and at least four of the minor compounds also play important roles in the hydration reaction. In order to avoid complicating matters, the present discussion will be restricted primarily to the four major compounds, which constitute usually more than 90% of a portland cement. The relative amounts of these compounds vary from cement to cement. Actually not only the amounts but the compositions of these constituents also vary to some extent, but the variation in composition of the individual components will be neglected for simplicity.

Jan 1, 1963

By T. J. Batchler

"INTRODUCTION A variety of standing supports are being applied in underground coal mining operations to assist in providing stable mine entries. Standing support performance requirements depend on the nature of the ground deformation behavior, and therefore require a good understanding of the interaction between the support and ground to achieve an optimum roof support system. Mining operations often employ standing support strategies that are unique to their mine. A support system that functions successfully in one situation could fail in another situation. It is important that the design and installation of the standing support systems provide the highest probability of preventing roof falls. Considerable research and development has been conducted by support manufacturers to develop standing support technologies for the mining industry. The National Institute for Occupational Safety and Health (NIOSH) researchers, with the cooperation of various support manufacturers, have developed a testing protocol that evaluates performance characteristics of these standing support systems.. Using this protocol, each of these support systems has gone through rigorous safety performance testing under controlled loading conditions in NIOSH’s Mine Roof Simulator (MRS). It is important to understand the unique performance characteristics of each type of standing support. This information allows mine operators to determine if the support system is compatible with the conditions in the mine and to compare each support system and determine if that support will provide equivalent or improved support capability. This paper provides a comprehensive summary of support performance to facilitate this objective. SUPPORT DESIGN CRITERIA AND THE GROUND REACTION CURVE Standing roof support systems are designed to prevent unplanned roof falls. The selection of the standing support is based on the interaction of the support with the surrounding rock mass, and its function is to assist the primary support system in maintaining the integrity of the immediate roof. The standing support works to control the immediate roof structure by resisting deformation that contribute to delamination of the bedded layers and displacements that lead to separation of the bolted zone from stable roof structures above the bolted horizon (Barczak, 2005). Standing supports should be installed early enough and develop sufficient capacity to bring deformation of the ground into equilibrium before a critical deformation is reached that leads to a detached block condition, at which point the standing support will be required to carry the entire dead weight of the detached rock mass to prevent a roof fall from occurring (Mucho, 1999). The ground reaction curve (GRC) can be used to assist in determining the compatibility and design requirements for a support system. It is important to understand the significance of the ground reaction relative to the support design requirements. The ultimate objective is to match the support behavior to the ground response and create equilibrium (stability) of the rock mass. This equilibrium is accomplished when the support loading intersects the ground reaction curve (Figure 1). Essentially, the ground reaction concept implies that the convergence in the mine entry is controlled by the magnitude of the support resistance. However, as a passive support, the standing support develops its loading through convergence. As such, the support needs to maintain its load capacity through the associated deformation of the ground and resulting entry convergence until the equilibrium condition is reached. This requirement causes factors such as the support stiffness, peak capacity, yielding characteristics, and stability to be fundamental to proper support design and application. NIOSH contributes to providing this understanding through full-scale performance testing of support products in the Mine Roof Simulator."

Jan 1, 2017

By Y. H. Hu, X. X. Zhang, Z. F. Dai, H. J. Huang, Q. S. Huang

"In order to get a more comprehensive understanding of the interaction of fine fluorite particles and bubbles, the electro-flotation was conducted, a high speed CCD was used to determine the bubble size distribution, and the results were analyzed using the models of collision and attachment. The electro-flotation was performed in a modified Hallimond tube. The results show that for different fluorite with size of 0 -10µm, 10 -38µm, 38-74um, there is a matching range between the different particle sizes and cathode aperture size (38um, 38um, 74um) to reach highest recovery. In addition, improving the concentration of collector is benefit for the flotation recovery due to the ability of collector to decrease the bubble size and prevent the merger of bubbles. Furthermore, theoretical calculation of collision, adhesion probability and collection probability is in agreement with the experimental data for electro-flotation recovery of fluorite.INTRODUCTIONFluorite is widely distributed, and has been found in more than 40 countries around the world. As fluorite minerals are easy to float, flotation is used as the best method of the current recovery of fluorite (Yang and Ai, 2016; Chen et al., 2017). In the field of mineral processing, the flotation of fine particles is particularly difficult, caused by the small quality and large surface (Sun et al., 2006). Flotation is now considered to contain three subprocesses, including the collision, attachment and detachment between the particles and bubbles (Sun et al., 2011). The collision of particles with bubbles is related to factors such as particle size and density, bubble size, bubble rise rate (Qin et al., 2012). Zongfu Dai et al. (2000) summarized the particle-bubble collisions models in detail and compared the experiment results with the model predictions. However, particle-bubble interactions occur in complex and turbulent flotation environments (Xing et al., 2017). Both thermodynamics and dynamic factors affect the adhesion of particles on bubbles surface (Schulze, 1989; Shahbazi et al., 2010). Scheludko et al. (1976) believes that the necessary condition for successful adhesion of particles on bubbles is that the contact time is greater than the induction time. The probability of adhesion between particles and bubbles increases with the increase of bubble size, but if the particle size is too small, the probability of adhesion decreases instead (Ren, et al. 2014; Norori- McCormac et al., 2017). After the particles adhere to the bubble surface, the particles will slide down to the bottom of the bubble due to gravity. At this point, the gravity, inertial centrifugal force and fluid force promote the desorption of particles from the bubble surface, while the surface tension, surface hydrophobic force maintain the stability of particles-bubble combination (Ralston et al.,2017). In addition, in the process of rising to the foam layer, desorption can also occurs. The purpose of this study is to observe the flotation behavior of fine fluorite with different size and to get a more comprehensive understanding of the interaction of fine fluorite particles and bubbles."

Jan 1, 2018

By W. M. McCardell, W. O. Winsauer, M. Williams

The mechanism by which an electrical potential difference is developed between two salt solutions separated by shale is shown to be a consequence of the electrical double layer of the shale surfaces. A mathematical derivation is presented to show -the dependence of the potential on the shale characteristic.? and on the concentration of the salt solutions. The equations developed describe adequately the potential-concentration behavior of a long shale core. The equations also describe the variation of potential of sand-shale mixtures with variation of clay content. Ion adsorption i* an important factor in he developments of the surface charge on the shale. and electrical resistivity and ion transference number data are emlployed to estimate the increase of surface charge with concentration. Since the potential is shown to be dependent on the characteristics of the particular .system. water salinities estimated from the potential log by previously proposed methods may be low in some rase;. INTRODUCTION That the electric well log exists today may he attributed to the ingenuity of the Schlumberger brothers who adapted to the logging of wells techniques which were originally developed as surface prospecting methods for the location of ore bodies Empirically it was found that the potential curve of the electric log usually gave values for clean sands which were negative with respect to the values for shales. It was suggested that the potential was responsive to porosity. It was postulated in explanation? that the potential was the sum of a streaming potential, which differed for sands and shales, and of an "electro-chemical" potential of undetermined origin. Mounce and Rust in 1943 showed that the streaming potential is small in most cases and that the potential is generated by a process in which shale and a salinity difference play-essential party. Dickey.:' in the same year, concluded that the potential is dependent upon adsorptive properties of reservoir rock. Wyllie in 1949. and Wyllie and Patnode, in 1950, measured the potential-: between two salt solutions separated by barriers of either naturally-compacted or artificially-compacted shales and concluded that the potential can be expressed by where E is the potential R is the gas content F is Faraday's constant T is the absolute temperature are the activities of the two uni-univalent solutions These authors postulated that shale. in the ideal case is impermeable to the migration of negative ions. Any potential less than the "ideal" shale potential was considered to be due to imperfections in the shale barrier. Although the studies by Wyllie and Patnode of the development of the shale potential are fairly recent. investigators in fields other than well logging have discussed the mechanisms responsible for analogous potentials over a period of several decades. Although it is evident that much thought has been devoted to the question of the origin of the potential observed in wells, it is also apparent that all of the explanations presented to

Jan 1, 1953

By Christian Hoyme, Jochen Maurer

Most of the current foundation projects are suffering from disconnected information silos. In the first silo there is the planning of the project with corresponding data, presented by paper or digital drawings. Here will Building Information Modeling (BIM) be one of the trends for the future. We will see more and more projects leaving the “old way” of 2D drawings and moving into 3D planning including metadata of the foundations. But even with a perfect BIM model of a jobsite, we are not at final end of digitalization. While execution of the project at the jobsite, a second data silo is evolving. Data collected directly from construction equipment and manual measurements is currently undervalued in most projects. Paper is passed to the equipment operator and major data from measurements on site are noted on paper and digitized afterwards. Automatically collected data is not be used to create site progress reports or similar report. So, the real “data” just flows around without connection to any other data already existing in projects. And then the third silo arises: The documentation of the project. Data collected on paper es reentered to create some basic documentation of the work handed over to the client. Spreadsheet software is still the “tool-to-be-used” to create at least some documentation. Finally, the documentation is not connected to the data created while planning and not connected to the automatically collected data from the jobsite. A connected jobsite in the foundation industry must link these information silos and have to create a full data-workflow from the design through the execution to the as-built documentation. INTRODUCTION Building information modelling (BIM) is currently the most popular term of construction business in Germany and probably all over the world. But as often there are many different definitions out there and everyone has his own definition or at least understanding what BIM is about. But for sure it is the most relevant for the construction industry in the near future. Most popular is the digital twin for the upper structure of a building. In most cases the BIM models just shows the building itself, but there is more to be implemented. For example: projects where a special foundation is needed, BIM should include also the foundation elements with meta data. There are several advantages. Not only the clash detection of anchors, but also the possibilities to check the interaction with neighbor constructions, power lines and so on are a use case. For sure most of the special foundation elements are not relevant for the whole lifecycle of a building. But during construction and later the demolition the information about the hidden elements is important and gives a benefit to all stakeholders. In the future there will be not the question: “What is already in the ground?”. The risk for following construction projects on the same ground will be minimized.

Jan 1, 2019

By Tell Ertl

THE Piceance Creek Basin in northwestern Colorado is believed to contain the richest large deposit of oil shale in North America. The major portion, about 1650 sq miles, is bounded by the White River on the north, the Grand Hogback, which runs from Meeker to Rifle, on the east, the Colorado River to the south, and the drainage basin of Salt and Douglas Creeks on the west. The Basin is a plateau 7000 to 9000 ft high, composed of 3000 ft of the Green River series of Eocene age and surrounded by a steep escarpment of 1000 to 3000 ft. From the escarpment the beds dip gently toward the center. Although oil shale is found in all members of the Green River series, the rich thick beds are found chiefly in the Parachute Creek member. This is normally capped by 100 to 200 ft of the Evacuation Creek, the youngest member of the Green River series. Actually the Piceance Creek Basin oil shale is not a shale, nor does it contain oil. It is magnesium marlstone holding solid organic matter capable of being broken down by heat into gases, some of which can be condensed into oil. The marlstone is resilient nonporous rock, difficult to sample by pick or hammer and moil. Many companies and individuals prospected the Colorado oil shale shortly after the first World War,' see Fig. 1, but because of the discovery of large quantities of petroleum in the late 1920's in Cali- fornia, Oklahoma, and East Texas, interest in oil shale development waned and did not revive until World War 11. In 1944 the writer, employed by the Bureau of Mines, prospected the high grade oil shale in numerous places along the southern outcrop of the Piceance Creek Basin. Several channel samples about 100 ft in length were cut, see Fig. 2. An eight-man crew needed a week to cut a satisfactory channel 80 ft long in the cliff face. The Phillips Petroleum Co., the Union Oil Co. of California and others also prospected the oil shale outcrop. In 1945 the Bureau of Mines initiated a core drilling program for the purpose of obtaining accurate samples from the Piceance Creek Basin. The U. S. Geological Survey set up a program for the geological study of the Basin that is still going on." Until the end of 1951 a total of 31 holes was drilled for core with diamond drills, and, in addition, cuttings through the oil shale have been obtained from 4 gas wells drilled by standard rotary oil well rigs. The Bureau of Mines drilled 12 of the holes, the Union Oil Company of California 8, the Standard Oil Company of California 6, the Sun Oil Company 3,

Jan 1, 1953

By B. G. Klugh

The present paper represents a preliminary investigation of the ultimate structure of iron-bearing materials which have been subjected to heat treatment for the purpose of agglomerating the fines, or for chemical changes, or for both. Primarily, the object of this inquiry was to determine the relation of the microstructure of each of these materials to its specific susceptibility to the action in the blast-furnace. It is hoped that this small contribution will serve as a nucleus to a line of research that will throw some light upon the debated questions involved in blast-roasting. Thus far the investigation has been conducted along lines of analogy of known principles, rather than through the application of any well-defined system of microscopic petrography. This is obviously due to the fact that we are dealing with ma-terials which are the artificial products of a new art, rather than with the natural materials from which the essence of the pure science has been evolved. In the limited time allowed for this research, it has been conducted upon those materials the chemical content of which allows of their use commercially in the blast-furnace. The following microphotographs are arranged in the order of the degree of complete fusion to which the mass in question has been subjected, in effectively binding the particles together. A very notable fact here clearly demonstrated is that the degree of fusion to which the material has been subjected is inversely proportional to the reducibility of the product. The characteristic of the material under consideration to which reducibility is almost universally attributed call be progressively traced in the following arrangement, through the identity of the obvious microscopic constituent. Furthermore, the degree of fusion to which a bod? has been subjected is recorded in the presence of resultant products of fusion in that body. Such readjustment is generally apparent

Jan 1, 1914

By P. V. Martin

SHORTLY after the middle of the nineteenth century, the invention of the regenerative open-hearth furnace and the development of the Bes-semer process stimulated a, rate of steel production whose magnitude created an unprecedented demand for pig iron. Revolutionary improvements in furnace design, auxiliary equipment, and operating technique enabled the blast furnace to keep abreast of the constantly increasing requirements of the steel mill. The development of improved blowing equipment, more adequate facilities for material handling, and particularly the general use of anthracite and coke to replace the physically weaker charcoal, led to a rapid expansion in both the height and volume of furnaces. Beyond a doubt,, however, the greatest single factor in blast-furnace improvement at this time was the use of the higher blast temperatures made available by the replacement of the recuperative iron pipe stoves by the regenerative Cowper brick stove. The increased blast tempera-ture not only resulted in greater output but also reduced fuel consumption far more than could be explained by the additional heat content of the blast. The progress of iron manufacturing was thus largely mechanical and thermal. Little attention was given tile chemistry of the process until the publication of the investigations of Sir Lowthian Bell.1 Bell's pains-taking experiments and investigations gave to the blast-furnace man his first real scientific conception of blast-furnace chemistry. Bell's recog-nition of the dual function of the carbon, the technical importance of reversible reactions and chemical equilibria, and his conception of the degree of oxidation of the carbon as shown by the analysis of the outgoing gases as a criterion of furnace efficiency, laid the foundation upon which has since been erected the structure of blast-furnace theory.

Jan 1, 1939

By Tell Ertl

THE Piceance Creek Basin in northwestern Colorado is believed to contain the richest large deposit of oil shale in North America. The major portion, about 1650 sq miles, is bounded by the White River on the north, the Grand Hogback, which runs from Meeker to Rifle, on the east, the Colorado River to the south, and the drainage basin of Salt and Douglas Creeks on the west. The Basin is a plateau 7000 to 9000 ft high, composed of 3000 ft of the Green River series of Eocene age and surrounded by a steep escarpment of 1000 to 3000 ft. From the escarpment the beds dip gently toward the center. Although oil shale is found in all members of the Green River series, the rich thick beds are found chiefly in the Parachute Creek member. This is normally capped by 100 to 200 ft of the Evacuation Creek, the youngest member of the Green River series. Actually the Piceance Creek Basin oil shale is not a shale, nor does it contain oil. It is magnesium marlstone holding solid organic matter capable of being broken down by heat into gases, some of which can be condensed into oil. The marlstone is resilient nonporous rock, difficult to sample by pick or hammer and moil. Many companies and individuals prospected the Colorado oil shale shortly after the first World War,' see Fig. 1, but because of the discovery of large quantities of petroleum in the late 1920's in Cali- fornia, Oklahoma, and East Texas, interest in oil shale development waned and did not revive until World War 11. In 1944 the writer, employed by the Bureau of Mines, prospected the high grade oil shale in numerous places along the southern outcrop of the Piceance Creek Basin. Several channel samples about 100 ft in length were cut, see Fig. 2. An eight-man crew needed a week to cut a satisfactory channel 80 ft long in the cliff face. The Phillips Petroleum Co., the Union Oil Co. of California and others also prospected the oil shale outcrop. In 1945 the Bureau of Mines initiated a core drilling program for the purpose of obtaining accurate samples from the Piceance Creek Basin. The U. S. Geological Survey set up a program for the geological study of the Basin that is still going on." Until the end of 1951 a total of 31 holes was drilled for core with diamond drills, and, in addition, cuttings through the oil shale have been obtained from 4 gas wells drilled by standard rotary oil well rigs. The Bureau of Mines drilled 12 of the holes, the Union Oil Company of California 8, the Standard Oil Company of California 6, the Sun Oil Company 3,

Jan 1, 1953

Discussion of the paper of CHESTER W. WASHBURNE, presented at the New York meeting, February, 1915, and printed in Bulletin No. 9S, February, 1915, pp. 469 to 471. ROSWELL H. JOHNSON, Pittsburgh, Pa.-I hope that this contribution of Mr. Washburne's is only the first of a series dealing more in detail with the very important problems involved. Pores are of two kinds: Those which are entirely inclosed, so that they do not belong to a system of communicating pores tapped by the bore hole or shot hole; second, those which do so communicate. Porosity, of course, includes both. But since pores of the first class are valueless to us, we should confine our attention to the latter, for which I propose the term "effective porosity." This should be measured by the Wisconsin method, based on the quantity of fluid that can be introduced by the aid of vacuum. Another factor which requires attention in this connection is the dependence of the extractability upon the rate of loss of pressure, as affected by the number of holes, and the rapidity of their completion, the existence of uncontrolled wells, the use by other operators of vacuum pumps upon the casing head, the exhaustion of a gas field in the same reservoir prior to the discovery of the oil, etc. The extractability depends upon the pressure available for the exclusion of the oil from the reservoir into the hole. The action of gravity in bringing oil into the hole is relatively small where the pores are very small, as is so frequently the case.

Jan 5, 1915

By T. H. Oxnam

INTRODUCTION. THE predominating value of the ores now being treated by the Palmarejo and Mexican Gold Fields, Ltd., is silver, although some gold is also carried. The present method of treatment consists of wet-crushing and concentrating, followed by the cyanidation of the unroasted sands and slimes. The sands are treated by leaching and the so-called accumulated slimes by a system of agitation and decantation. It is only within very recent years that the cyanidation of unroasted silver-ores has been commercially successful. In fact, at the time operations were begun at the cyanide-plant at Chinipas, February, 1902, I knew of no other leaching-plant treating similar ores successfully. The cyanide treatment of the Palmarejo ores differs but little from the ordinary practice in cyaniding gold-ores; and perhaps but little, if any, new information concerning the metallurgy of silver is to be gleaned from it. PALMAREJO MINE. The Palmarejo mines are located in the southwestern part of the State of Chihuahua, Mexico, on the foothills of the Sierra Madre mountains, at an elevation of 3,200 feet. The mills, 12. miles distant, are situated on the Chinipas river, near the town of Chinipas, which is about 150 miles northeast of Agiabampo, on the Gulf of California. Supplies are shipped via this port as this route is the best and most direct to the property. The ore-bodies in the Palmarejo mines have been deposited. along a series of rock-fractures, caused by an intrusion of eruptive rock. The most important of these fractures or fissures, both in width and value, are the Prieta and Blanca veins, which.

Jul 1, 1905

By Bhattacharyya AK

A two-dimensional finite element modelling technique is applied to predict the subsidence movements on a sloping ground surface above a completely mined panel. The modelling is carried out for the surface both directly and using a combination of an equivalent horizontal surface and a rays projection method and the result compared. The rays projection method provides the subsidence components on a sloping surface from the corresponding ones on an assumed equivalent horizontal surface through the point of mean elevation of the relevant part of the sloping surface. This method is used next to compare the subsidences, horizontal displacements and horizontal strains from the mining of a given panel at the surface for different inclinations. The results show that the magnitudes of the subsidence components are greater on the dip side of the slope from the point of the mean elevation, than the corresponding ones on the rise side and the asymmetry increases with the inclination of the surface. The findings are also compared with those of other research Workers.

Jan 1, 1992

By C. L. Clark, J. Russ

FOR many years attempts have been made to develop a laboratory test that would serve to indicate the proper temperatures to be used in the various hot-working applications to which metals may be subjected as they are being processed from the cast ingot to the desired finished products. That these attempts have not been very successful is indicated by the fact that most of the temperatures in use today in these operations have been developed over a period of years by trial and error. In other words, the selection of the proper temperatures for the hot-working of metals is generally an art rather than a science. Our knowledge with respect to the behavior of metals at elevated temperatures has been greatly extended during the past several years. While most of the work in this field has been done at proposed operating temperatures of equipment, rather than at processing or fabricating temperatures, one outstanding fact has been developed, which is applicable to the entire high-temperature range; that is, that the rate of deformation to which the metal is subjected is of the same order of importance as the temperature. The failure to properly recognize this fact has greatly retarded the development of a suitable laboratory test for determining hot-working temperatures. INFLUENCE OF RATE OF DEFORMATION ON HIGH-TEMPERATURE PROPERTIES It is not the intent of this paper to survey all the work that has been done on the effect of deformation rate on the properties of metals. The importance of this factor, however, was shown by Zay Jeffries1 as early as 1919, when he called attention to the existence of the so-called equicohesive temperature and to the effect of certain factors on the location of this temperature. Fig. I is a diagrammatic sketch showing the effect of temperature on the relative strength of the crystals and grain boundaries and the type of fracture that will result, depending on the location of the test, or working temperature with respect to the equicohesive temperature. Since the type fracture varies, it also follows that at temperatures below the equicohesive temperature the major deformation occurs in the grains; while at temperatures above, the deformation results either from the movement of the grains with respect to each other or recrystallization of the strained material occurs almost instantaneously, producing new crystals at the fracture. As previously indicated, it is an established fact that the position of this equicohesive temperature for any given metal is dependent on the deformation rate. For example, in 0.15 per cent plain carbon steel the location of this temperature under

Jan 1, 1945

By J. A. Sweet

The issues facing graduate training in the mineral processing industry are not too different today from those that prompted the initiation of the Anglo American Platinum Graduate Development Programme (AGDP) in 2002. Graduate metallurgists in South Africa enter the industry from different undergraduate programmes at various tertiary institutions, and so the knowledge and skills of the young graduates varies. Further, the geographical expansion of the industry combined with the downsizing of business units means that there are fewer opportunities for young graduates to be mentored through their first few years on site. Anglo American Platinum chose to address these issues by implementing an intensive, structured graduate training programme for all their new metallurgical graduates, known as the AGDP. The first two years of experience of the AGDP, from the viewpoints of both graduates and lecturers, were presented to the mineral processing community at the IMPC in Turkey in 2006 (Sweet et al, 2006). From the beginning, the programme was structured in a modular fashion to include a basic technical ?toolbox? including statistics, the scientific method and sampling protocols, while the mineral processing content comprised advanced learning in comminution, classification and flotation (later extended to include hydrometallurgy). Technical communication ? both written and verbal ? was included from the start. The programme was focussed very strongly on site work (?learning by doing?), with a major integrated site campaign conducted and analysed by each cohort. In 2012 the AGDP will accept its ninth cohort into the programme. This paper describes how Anglo American Platinum and the University of Cape Town have developed and adapted the programme over the last few years, in response to the challenges of the global recession, skills retention, and the changing operational needs of the company. The programme, which was drawn up to accommodate around 15 concentrator-only graduates, now accommodates 35-40 concentrator, smelter and refinery graduates annually. The programme has also been modified to facilitate new graduates spending most of their first year on the operations. The benefits of the programme for Anglo American Platinum have been tangible, and will be discussed in the paper. Keywords: graduate training, technology transfer

Sep 1, 2012

By G. H. Robbins

"Originally presented at TORONTO 94, CIM-AGM, this paper has been updated to reflect the present status of business development for theSO2/AIR process. The paper reviews the back-ground leading to the invention, discusses the process chemistry and historically tracks the commercial development. Engineering and cost considerations are presented.IntroductionThe year 1994 was particularly significant in terms of the technical and business development of the INCO SO2/AIR cyanide destruction process. The year marked a decade of service to the world mining community since INCO acquired the Canadian patent in 1984. In that time period, the technology had become widely recognized as the state-of-the-art process in the field of cyanide detoxification and today we enjoy the distinction of having licensed the process at over 50 project sites worldwide. The application for the process has mostly been in the mining industry in precious metal recovery plants where it offers treatment for a wide range of waste streams such as: CIP/CIL slurries, Merrill-Crowe barren bleed solutions and/or re-pulped filter cakes, tailings pond water recycle or discharge, make-up water to flotation circuits and feed to underground backfill plants. The process also applies to the treatment of high cyanide rinsewaters from metal plating shops. More recently the process is being applied to the rinsing and abandonment of heap leach pads where it has proven to be a very cost-effective application of the INCO process. The distinct advantages that have led to the success of the process are the ability to work on slurries as well as solutions and the significantly low cost of sulphur dioxide products. The process is safe and easy to manage and uses all forms of SO2(liquid, gas or salts) which gives the process tremendous versatility with respect to geographic application. Having more than ten years of service"

Jan 1, 1996

By John Furness Park

The mining district is located in the northeasterly part of Nevada, between the Jarbidge River on the west and the East Fork of the Jarbidge on the east. The northern boundary of the district is but a few miles south of the Idaho state line—the gold-bearing area extending from this point south, for 5 or 6 miles. • The Jarbidge Mountains, in which the ore deposits occur, range from 5000 to 11,000 ft. in elevation, the most important mines being situated about 7000 ft. or higher. The town of Jarbidge lies along the Jarbidge River and is reached by stage from Rogerson, Ida., the nearest railroad point. During the summer months, the camp may be entered from the south by way of Deeth, Nev., but no regular transportation facilities are available over this route. History The mineral deposits were not discovered until 1909, when D. A. Bourne, panning along the river bank, found gold in. the gravel at the mouth of a small stream flowing into the Jarbidge. He prospected in the vicinity of this stream, later known as Bourne Gulch, and shortly after located the North Star claims. During the following spring and summer (1910), the camp of Jarbidge grew from nothing to a town of 2000 people and the hills surrounding it were practically all taken up by mining claims. Most of the work done during the first year or two consisted of trenching and open-cut prospecting. Tunneling was started on a number of claims and many veins were uncovered. Mills were built and operated on a few properties, notably the Pavlak and the North Star. These ran only a few months, however, when they were closed down because of extraction and financial difficulties. A period of development followed in which the majority of the present producing mines were opened. The Elkoro Mines Co. acquired a number of claims in 1915 and started work on the present mill in 1917. Since that time other properties have been taken over until this company is by far the largest operator in the district. Only one other company is now actively engaged in mining, the Bluster Mining & Milling Co., which has

Jan 1, 1925