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By Timothy A. Clancy

To help reduce the Nation's dependence on imported chromite, the Bureau of Mines is conducting research on the use of dolomites as an alternate material. Dolomite is a plentiful domestic resource and offers certain advantages as a refractory raw material. A review of the literature has indicated that there are many sources of high-purity dolomite in this country and that European nations use a greater proportion of dolomite refractories, primarily in steelmaking, than the United States, The Bureau of Mines characterized 14 domestic dolomites as to chemistry, density, mineralogy, microstructure, and thermal behavior, to develop baseline data on their suitability as refractory raw materials.

Jan 1, 1983

By Charles F. Coleman

Kinetics studies and other rate measurements are reviewed in the amine extraction of uranium and of some other related and associated metal ions. Equilibration' is relatively fast in the uranium sulfate systems most important to uranium-hydrometallurgy. Significantly slow; equilibration-has ' been encountered' in some other systems. Most of the recorded rate information, both qualitative and quantitative; has come from exploratory and, process-development development work, while some kinetics studies have been directed specifically toward elucidation of, extraction mechanisms. In contrast to some other extraction systems, relatively little attention has been given to the kinetics of uranium extraction by amines. This is because investigators have not been troubled by slow extractions. Instead, when rate limitations have been of concern in amine extraction (Amex) process developments, they have been mainly from slow phase disengagement rather than from slow equilibration. Nevertheless, taking uranium together with several other elements that are closely related to it or associated with it in typical processes, a considerable body of rate information has been recorded.

Jan 1, 1979

By David J. Hoadley

This report describes the development and limited testing of a semi-automatic, raise climber, Compact Service Hoist System designed for stope access in underground metal and nonmetal mines. Demonstrated capabilities of the system include a 1,000-lb payload capacity, control from the traveling cage and from up to three remote stations, operating in vertical or inclined raises 3 ft in diameter and up to 300 ft in length and a travel speed of 50 ft/min. The system has the capability of operating in crooked raises because the conveyance climbs two stationary wire ropes suspended down the raise. The drive unit is electrically powered with power and control signals supplied to the drive unit through an umbilical 'cable also suspended down the raise. The system has been designed for portability, ease of installation and minimum raise development. The hoist has been demonstrated successfully in an above ground test tower. This report provides a detailed description of the hoist design and its demonstrated performance to date.

Jan 1, 1985

New Trade Status for Mainland China--On January 24, the Congress approved a most-favored-nation trade status with Mainland China for both imports and exports. A Presidential Proclamation had been issued earlier in anticipation of the Congressional action. Import duties on such commodities as tungsten, mercury, and antimony are automatically decreased. Defense Production Act Extended--The Defense Production Act of 1950 was extended 60 days to March 28, 1980. The provision for the usual 2-year extension of the Act is reportedly included in an omnibus energy bill that is tied up in committee. The Act under Title III provides for the expansion of productive capacity and supply and, more specifically, it gives priority to defense contracting where defense and non-defense interests conflict

Jan 1, 1980

By A. Fawcett, B. C. Dyer

Abstract - The basis of the tomographic velocity imaging technique is briefly described and an application of the method to detect and image a cross-section through a chromite pod is presented. Using the chromite application as an example, the relative costs of tomographic data acquisition and processing are compared with those of diamond drilling to obtain similar resolution. A number of different tomographic survey configurations and the potential role of the method in surface and underground exploration are discussed.

Jan 1, 1994

By M. D. Cooper

IN spite of the uncertainty in the bituminous coal industry during 1933, progress worth recording has been made. Along with other industries, coal has felt the effects of business stagnation, but even in the worst weeks of the past four years, .the total production of bituminous coal in the United States was seldom less than half the production in some of the best weeks of the more prosperous years, a record better than that of many industries. However, the competition of other fuels and sources of power, together with the increased efficiency in the use of coal, has brought anxiety to producers. This has resulted in pressure for reduction of costs, not always by the wisest means. On the other hand, the effort to survive has directed increasing interest toward research, a wholesome development in a difficult situation. Wages, limitation of hours of labor, and the NRA have occupied much time and thought. Following a period .of wage cutting paralleling price cutting, the industry found itself rather suddenly faced by the President's Agreement, followed in due course by the Code, and then in many places by the agreement with the United Mine Workers. Although there is still some uncertainty in regard to the detailed working out of the new arrangements, there seems to be an honest endeavor by the signatories to the Code and Agreement to work them out in a straightforward manner.

Jan 1, 1934

By A. Fahimifar, H. Soroush

Abstract: Triaxial tests were conducted on the schist specimens with various anisotropic angles under confining pressures of 0, 7 and 15 MPa, and axial stress-axial strains, were measured and plotted for various conditions. The results obtained reveal the effects of schistose on the strength and deformability of the rock very clearly. Peak strength of the specimens for 00 and 900 schistose orientations are nearly the same. Modulus of elasticity of this rock varies with anisotropic angle. For 0 orientation modulus of elasticity increases to a maximum. Confining pressure increases the peak strength and improves the rock deformability. However, this effect is not the same for various orientations, and there are no similar trends for each anisotropy direction. Analysis of the results shows that consideration of a linear failure criterion such as Mohr-Coulomb is appropriate for the prediction of rock behaviour up to 10 MPa, rather than a non-linear one. The analysis also reveals that the friction angle and cohesion are affected by the anisotropy orientation, and this effect is more important for the cohesion than the friction angles. Resume: Les esseys triaxiales sur les echantillon d un roch schist avec les differents angles non-isotrop sous les tension lateral zero et sept et qoinze mega pascal (mpa) est fait et les covtraite et allongment unitaire sont mesure et leur curues est destine sous different condition les resultats obtenues montre les effets du schistosite sur le resistance et le ductilite vissiblement. Le resistance final sur les echantilions pour les angles o degre et 90 degree est equivalent. Le modoule d elasticite de ce roch sera difere par a port de l angle de stratification. Pour l angle o degree le valeur de modoule est le maximum. le pousse lateral augmenterai le resitance final, et sera amilterai le toleran le de ductilite. Mais cette effet bn est pas unigue pour les different stratification, et pour les diferents directions no– isotrop it n y a pas le meme solution. L analyse des resulitats montre que le criterre de ruin comme mohr–colomb est moderate pour le pousse lateral jusq av lo mega pascal , et ce n est pas neccesaire d utiliser de criterre no–linear . Cette analyse aussi montre que l angle de frottement et cohsion est en relation de la direction no–isotrop, et cette effet est olus important pour le cohsion par a port de l angle de frottement . Abriß : Dreiachsige Prüfung wurde auf den schist Exemplaren mit verschiedenen anisotropic Winkeln unter Bestätigen von Drücken von 0.7 und 15 MPa geleitet, und axiale Spannung axiale Spannungen, wurden gemessen und für verschiedene Bedingungen wurde geplant. Die Ergebnisse haben die Wirkungen von schisocity auf der Kraft und dem deformability des Felsen sehr deutlich erhalten offenbart. Maximale Kraft der Exemplare für 0° und 90 sind° schistos Orientierungen beinahe das gleiche. Modulus der Elastizität von diesem Felsen ändert sich mit anisotropic Winkel. Für 0° vermehrt Orientierung modulus der Elastizität zu einem Maximum. Einschränkender Druck vermehrt die maximale Kraft und verbessert den Felsen deformability. Aber ist diese Wirkung nicht das gleiche für verschiedene Orientierungen, und es gibt keine ähnlichen Tendenzen für jede anisotropic Richtung. Analyse der Ergebnisse zeigt jener Überlegung Kriterium eines linearen Ausfalls wie zum Beispiel Mohr Coulomb passend für die Voraussage von Felsen Verhalten bis zu 10 MPa, anstatt eines nicht linear ist. Die Analyse offenbart auch, daß der Reibung Winkel und Bindekraft werden beeinflußt von der anisotropic Orientierung, und diese Wirkung wichtiger für die Bindekraft ist, als der Reibung Winkel

Jan 1, 2003

The Kaiser Aluminum and Chemical Corp. announced plans to raise June ingot prices by 4 cents to 57 cents per pound. Producers? April value for 99.5 percent unalloyed aluminum ingot was at 53 cents per pound. Domestic merchants last month were quoting the metal at 48-49 cents per pound. Primary aluminum producers began restarting production facilities following the settlement of the coal strike. Noranda Aluminum Inc. recalled workers to prepare potlines for production at its plant at New Madrid, Mo., which had closed February 14, 1978 due to the shortage of coal. Eastalco Aluminum Co. resumed full capacity production at its Frederick, Md. smelter where production had been cut by 30 percent. Anaconda Aluminum Co. resumed full capacity production at its Sebree, Ky. smelter.

Jan 1, 1978

By H. Ehnes

"“Industry 4.0” – “Mining 4.0” - perhaps you have already heard of these terms? These keywords signify the next stage of industrial production. The internet and production technologies are growing closer together. Machines can communicate with one another, wherever they may happen to be located. The “Internet of Things” is the appropriate term. But what does SAFETY 7.0 mean? It is both brand new and traditional at the same time. It also has to do with the success of companies, with efficient production. And yet there is a great deal more at stake. It has to do with our lives and our safety – the supreme commodity in this world. What exactly SAFETY 7.0 means, what the number 0 stands for and the meaning of the number 7, and what this all has to do with mining will be explained in the following article. Mining is a fascinating undertaking. Mining is indispensable for a country’s economic development, whatever that may concern: infrastructure, energy supplies or raw materials for industrial production. Mining has brought forth many technological developments and innovations that can currently be found in our daily lives. Mining is impressive, grandiose and repeatedly fascinates mankind with its immense dimensions. Miners throughout the world still work hard and, for this reason, are bound to one another in a special way. In mining, every man looks out for the other; you have to be able to rely on each other. That creates a strong bond. The other side of the coin is that mining and disasters belong to normality in the media and thus also in our perception. Accidents at work and even catastrophes occur in mining, quarries, or raw material operations almost on a daily basis somewhere in the world. They are often associated with extremely serious injuries, or even a fatal outcome, for the miners affected and, in turn, dramatic consequences for the families of those involved. It could be in China, India, Russia, or somewhere in Africa, Asia or America – it mostly does not happen in front of our door or in our neighbour- hood. Perhaps because of this in the daily concert of negative headlines, we do not register these catastrophes any more in our minds. We write them off under the heading “Nothing special”, since there are, day in day out, more terrible news items about wars, civil wars, famines, or ecological disasters. Things only really change if there is a dramatic number of deaths or when we are personally affected, close by in the vicinity, or can witness the rescue action live. In Europe, these three mining disasters in particular have recently generated media resonance:"

Jan 1, 2016

By C. Okrusch, C. Roos, M. Akers, S. Rosenthal

Modern mining consistently faces controversy. Public sentiment impacts the permitting and development of mines, so a quality public relations (PR) program for mining companies may improve society’s impression of the mining industry. Developing mines face more permitting challenges than operating mines, which stems from a lack of societal trust given the history of mining and its impact on the environment. Two case studies were selected based on the type of public controversy they face to demonstrate how pervasive permitting issues are in industry. Both Pebble Mine, owned by Northern Dynasty Minerals (NDM), and Black Butte, owned by Sandfire Resources America Inc (SRA), experienced difficulties with their water permitting due to potential risks their mine developments posed to local fish populations. Pebble has, to date, failed in all of their attempts to become permitted due to concern for the water and the fish. Black Butte dealt with the same problems, on a smaller scale, but was able to become permitted. These two mines will be discussed in detail including local history, mine setting, mining history in America, prevalent culture groups, technology development, and intercultural communication competence (ICC). The mining industry needs to evaluate its ICC skills since ICC directly determines the effectiveness of PR. Based on Barna’s Stumbling Blocks for intercultural communication, methods for improving the mining industry’s PR will be suggested in the hope of easing the permitting process for future mines by developing ICC.

Mar 2, 2022

By K. C. Dean

Discarded automobiles represent the greatest single resource of reusable metals, plastics, and rubber in the United States. This report presents results of Bureau of Mines research, conducted from 1965 to 1983, on separating and recovering useful materials from the scrapped hulks, using old and new metallurgical techniques combined with standard scrapyard methods. The Bureau determined the materials composition of three composite cars designated as circa 1960, mid-1970's, and early 1980's, and used these cars to study smokeless incineration and hand-sorting techniques. In studies on treating rejects from automobile shredders, the Bureau designed a process that included air classification, water elutriation, magnetic separation, handpicking, and heavy-medium separation, and also investigated cryogenics and liquation. Complete recovery of cop-per and other metals was economically made by hand and tool dismantling, leaching, or selective melting of starters and generators. Techniques are also discussed for plastic recovery and waste tire treatment.

Jan 1, 1985

By Christopher Mark

This proceedings volume contains papers presented at W U.S. Bureau of Mines (USBM) technology transfer seminars on New Technology for Longwall Ground Control. These seminars were conducted in Washington, PA, on April 12, 1994, and Denver, CO, on May 10, 1994. The papers herein describe several new, highly practical USBM technologies now available for ground control in longwall mines, including lie Coal Mice Roof Rating (CMRR), cable bolts, the MULSIM/NL model, and the Wood Crib Performance Model. Other significant topics addressed include longwall panel layout, coal pillar design, horizontal stress in longwall mines, roof support selection for gate entries, and ground control monitoring.

Jan 1, 1994

By William O. Vanderburg

This paper gives the results of a reconnaissance of the mining districts in Humboldt County, Nev., made during the month of June, 19373/. During the field work, virtually all the mining districts in the county were visited and many data were obtained on a number of active and inactive properties. No attempt has boon made to include in this report all the properties in the various mining districts, and it should be emphasized that whether or not a property is mentioned herein has no being on its merit. The report covers the location of the various mining; districts, types of deposit, information on past operations and current activity, and general information likely to be useful to operators, investors, and others interested in mining. The geology of the deposits is discussed only briefly. The names of the various mining districts mentioned in this report are those generally used when they were organized for purposes of record and regulation. As organized, the districts embraced largo areas with no definite boundaries, and the names have little significance.

Jan 1, 1938

By A. L. Podia

The purpose of this research was to develop a system capable of detecting changes in the structure of rocks, leading to failure of mine roofs, and/or excavations. A prototype system was developed, field tested and delivered to the United States Bureau of Mines for further evaluation and research. This system is based on the analysis of acoustic signals generated on the surface of the roof by an impact device and which are reflected or backscattered by flaws and discontinuities in the rock. The specially designed impact source is capable of generating high frequency acoustic signals with excellent repeatability. The system can also be used in conjunction with conventional acoustic pulse transducers. The received signal is digitized and the data transferred to a minicomputer for processing and display. This capability allows the immediate determination of wave velocity and/or distance to a reflecting interface. Various data processing techniques such as averaging, differentiating, and comparing of different signals can be selected by entering the appropriate commands on the keyboard. Being a programmable system it is possible to implement more advanced signal processing techniques. All results as well as the signal are displayed on a CRT. Furthermore, a permanent record of the data can be generated on paper tape, which can be reentered and processed at a later date. A communications interface allows transmission of the sampled signal to a large scale re-mote computer. The system was tested extensively in the laboratory, and field tested at the York Canyon Coal Mine. These tests proved the feasibility of operation in the mining environment. Results indicate that further investigation and development will have to be undertaken to fully develop the potential of this system in satisfying the goals of this research.

Jan 1, 1973

By Elton L. Litchfield, Milton L. Weiss

Studies were made on the projectile impact sensitivity of explosives by subjecting explosive samples to the impact of metal projectiles fired from a 0.50- caliber gun . The projectiles , in the form of right cylinders , made plane surface to plane surface contact with the explosives . Pressures in the explosive were investigated with an expendable pressure transducer in some instances . The physical model of the projectile - explosive interaction describes , in principle , the duration of the peak shock pressure in terms of the projectile and explosive geometry and the steady- state penetration of the explosive . Of the explosives studied , liquid hydrogen- solid oxygen and liquid oxygen - solid or liquid hydrocarbon fuel were the most shock sensitive ( requiring an initiating shock of about 1.0 kb or 987 atmospheres pressure ) ; cast TNT was the least sensitive ( requiring an initiating shock of more than 110 kb pressure ) . Measurements of pressure in the explosive showed some moderate space resolution by the transducer and gave pressure distributions in agreement with expectations from the model of the shock processes . The appearance of the recovered projectiles and the calculated initiation shock pressures suggest that the solid explosives were initiated directly to high- order detonation , whereas the liquid explosives were probably initiated to low- order detonation-- with a subsequent , later transition to high- order detonation .

Jan 1, 1965

By Lawrence Addicks

T HIS has been a most momentous year in the annals of the Institute. We have been in the midst of a situation which, were it not for the convulsions of social unrest with which life is surrounded on every side, would have attracted the attention of the world at large. I do not refer to the desperate campaign for new members. That has gone on much as usual except that, this being leap year, the annual proposal to the M. & M. Society has been omitted. Nor do I refer to the desperate situation which we found in other directions, the spread of Bolshevism, the burning of the Engineers' Club, the fact that the selling of copper appears to have become one of the lost arts. No, I speak of the great question which has to be. settled once and for all, as to whether this great Institute should adopt simplified spelling. The whole trouble started in the ranks of the California Hysterical Society. It appears, while most of the San Francisco members can read and write, several of them cannot spell. It also appears that the Secretary, in editing the Transactions, has perhaps made just a little bit too much of a point of employing the correct Stoughton idiom. At any rate, the rebels filed an amendment to the constitution, and the stage was set for civil war, with perhaps more stress on war than on civil.

Jan 1, 1920

By George P. Demopoulos, Nima Parsi Benehkohal, Marianna Uceda

Lithium-ion batteries (LIBs) find wide range of applications from portable electronics to electric cars and stationary storage or renewable energy. LIB electrode fabrication is done through mixing the active material (Li-ion host) with carbon (conductive component) and polyvinylidene fluoride (PVDF), which acts as a binder. These components are dissolved in N-methyl-2-pyrrolidone (NMP) to form a paste which is then doctor bladed onto the aluminum current collector. NMP is a toxic chemical and the overall fabrication process remains costly. Efforts are made of eliminating NMP by (1) replacing the binder and (2) using a new fabrication method. Of particular interest among these new methods is electrophoretic deposition (EPD). Via the application of DC potential, particles in suspension can be electrophoretically deposited on different conductive substrates in a relatively fast rate rendering EPD feasible for industrial application. A key aspect for successful application of EPD is the formulation of a stable suspension. Within the McGill HydroMET group, we explore the potential of EPD in fabricating LIB electrodes having demonstrated its effectiveness in the case of P25 nanotitania/carbon anodes. The performance of EPD fabricated TiO2/C electrodes is compared to standard PVDF-based electrodes and shown to have comparable charge capacity. This method is now being extended to other electrode materials. In this paper an introduction to the EPD method will be made and subsequently its use in fabricating LIB electrodes will be described. The performance of the fabricated batteries is evaluated via galvanostatic charging/discharging and cycling tests.

Jan 1, 2016

By H. Grothe

El presente texto señala las posibildades técnicas y económicas en la instalación de una refinería de zinc y una fundición de plomo en el Perú. Para ello, se revisan los problemas técnicos que comprende (la materia prima y la elaboración). Respecto a los yacimientos y considerando como norma las extracciones actuales, se asegura la existencia de materias primas para un espacio prolongado de tiempo dentro de un período mínimo de 20 años. Asimismo, la calidad de las menas no sufrirá ninguna variación fundamental en este espacio de tiempo y las plantas de preparación existentes estarán en condiciones de suministrar a la nueva fundición suficientes concentrados, tanto en cantidad como en calidad.

Mar 1, 1960

By Borje Bjorkvall

At LKAB's plants in Lappland, Sweden, sintered pellets are manu-factured according to three different industrial processes, viz. shaft furnace at Malmberget, straight-grate at Kiruna and grate-kiln at Svappavaara. At present the total annual capacity amounts to 4.7 million tons. However, since it has been decided to erect a new straight-grate plant (2.5 million tons) at Malmberget, and because of the decision to extend and rebuild the existing plants, it is estimated that the annual capacity will be increased to somewhat over 8 million tons by 1973. The great majority of the pellets produced is exported. They are thus reloaded several times and generally speaking roughly handled, resulting in larger or smaller product losses on arrival at the point of use. It is there-fore of great economical interest to have a good control over the transport strength of the pellets by appropriate quality testing at the point of production. In addition to good transport strength, further demands are ob-viously made on pellets destined for blast furnace operation. The blast furnace burden must maintain a good permeability for the gas. The pellets must thus have a favourable size distribution and must not be so weakened by reduction that they disintegrate under the stresses and clog the blast furnace shaft. Furthermore, the burden must have good reducibility. An increase of the rate of reduction can obviously mean increased blast furnace capacity and reduced coke consumption. In order to optimise the properties of the pellets in these respects, the producer must also be thoroughly familiar with their behaviour during reduction, particularly as the customer's interest in the reduction properties of the pellets' has increased over the last few years. Up to now the only quality demands the customer has made have generally had to do with the cold strength and the screen analysis. Thus a quality control of in addition to good transport strength, further demands are obviously made on pellets destined for blast furnace operation. The blast furnace burden must maintain a good permeability for the gas. The pellets must thus have a favourable size distribution and must not be so weakened by reduction that they disintegrate under the stresses and clog the blast furnace shaft. Furthermore, the burden must have good reducibility. An increase of the rate of reduction can obviously mean increased blast furnace capacity and reduced coke consumption. In order to optimise the properties of the pellets in these respects, the producer must also be thoroughly familiar with their behaviour during reduction, particularly as the customer's interest in the reduction properties of the pellets' has increased over the last few years. Up to now the only quality demands the customer has made have generally had to do with the cold strength and the screen analysis. Thus a quality control of

Jan 1, 1972

By Stephen A. Orr

Underground mining is a dynamic art and science with a diverse set of design, production, and economic criteria that must be considered before selecting an optimal method to extract the ore. While all methods can be technically classified as either self-supported, supported, or caving, the multitude of subsystems and existing variations bear witness to the fact that each orebody is unique and, as such, justifies an individual approach to optimize mineral extraction. In this sense, underground mining is an art. The ability to evaluate the unique characteristics of each ore body and utilize sound engineering principles to design the optimal system constitutes effective method selection. The task by no means ends at this juncture, however. Subsequent implementation requires an ability for modification. Very rarely are all the facts available to make a concrete decision prior to development of the resource. As a result, the risk of a wrong decision can never be eliminated. This requires a significant degree of flexibility with each method. Each unit of exploration, development, or exploitation work contributed to a deposit enhances knowledge of the ore body. The best mining methods are those that correctly account for the known parameters but provide an allowance for change at minimal cost and adapt to unanticipated conditions.

Jan 1, 2008