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By Steven W. Schmauch

The Ruby Mountains study area encompasses 75,615 acres managed by the U.S. Bureau of Land Management in Madison County, MT. A mineral survey was conducted by the U.S. Bureau of Mines and U.S. Geological Survey in 1984. Bureau of Mines personnel reviewed literature and county mining records, and examined prospects or mineralized areas to determine mineral resources. Geological Survey personnel evaluated the area by geochemical sampling and geophysical surveys. There are no organized mining districts and no current claims in the study area. Significantly mineralized quartz veins, shear zones, or talc bodies apparently do not exist within the study area. A small part of the Kelly Iron Deposit is inside, but dips away from the study area; the main occurrence is estimated to have 32 million tons of subeconomic resources that average 21 percent iron.

Jan 1, 1985

By Vaughan R. Voller

"Numerical methods for dealing with a temperature dependent conductivity are discussed. An approach based on a local application of a Kirchhoff transformation at the discrete level is presented. The application of this transformation - that does not require any inversion- is demonstrated on solving a two-dimensional test problem.IntroductionMuch is said in the recent literature on the modeling necessity of obtaining appropriate thermo-physical properties; in particular the requirement to account for properties that are ""strong"" functions of the depended variables, e.g., Temperature. Of course obtaining appropriate thermo-physical properties serves no purpose unless they can be accurately integrated into a discrete numerical calculation. The purpose of this paper is to examine how temperature dependent conductivities that exhibit discontinuities or rapid changes can be handled in a numerical code.The discussion will be made in the context of a control volume finite element method [1]. After a brief outline of control volume finite element fundamentals basic methods of dealing with discontinuous or rapidly changing thermal conductivity are discussed. This is followed by the presentation of the recently proposed local Kirchhoff method [2,3], The paper concludes with an investigation of the performance of the various conductivity schemes in solving two dimensional problems. This testing clearly shows the advantages (accuracy and implementation) in using the local Kirchhoff method."

Jan 1, 2001

By Robert J. Greaves

High-resolution seismic reflection profiling can be used to evaluate detailed struc¬tural and stratigraphic features of coal pros¬pects. Since most coal prospects are relatively shallow (less than six hundred meters deep), the vertical and lateral resolution of seismic data can be significantly improved by high sampling rates in space and time. The case study present¬ed shows the effective use of seismic data in evaluation of the Wyodak coal at a prospective coal gasification site. The data were used to map the detailed structure and thickness of the coal and to search for lateral discontinuities, such as pinchouts and. faults. An important find was a paleochannel cutting across the base of the coal seam, which was later confirmed by drilling.

Jan 1, 1983

By Kefton H. Teague

Olivine was first described and named by Warner in 1790. It is an olive green to greenish gray colored magnesium-iron silicate containing a mixture, in solid solution, of fosterite (Mg2SiO4) and fayalite (Fe2SiO4). Ratios between fosterite and fayalite in olivine are somewhat variable, but in general olivine contains at least 85% fosterite. Specific gravity is variable also, depending on the ratios of fosterite to fayalite. As a rule it is in the 3.2 - 3.4 range. All commercial olivine is obtained from the rock dunite, the most basic member of the peridotite group. Dunites, in addition to being composed primarily of olivine, generally contain assessory pyroxenes and spinels (chromite and magnetite). Dunites', when altered by hydrothermal solutions or metamorphism, often contain alteration minerals such as talc, serpentine, chlorite, vermiculite and amphiboles. In the 1930's and 40's considerable research was conducted on olivine for use as a refractory, plant food raw material, magnesium source for metal, and a source for magnesium chemicals. This research met with only limited success.

Jan 1, 1977

By M. Aushouri, S. H. Mansouri, N. Aminizadeh

A thermo-chemical model of the Peirce-Smith copper converter in blowing the copper stage has been developed to predict the molten temperature. The key assumption of the model was that white metal and gas phases in the converter were in thermal and chemical equilibrium. In this model, the chemical reaction of white metal and oxygen was accomplished completely. So long as sulfur existed in the bath, the generation of Cu2O was frozen. The reaction rate was considered to be constant and controlled by the reacted sulfur. The converter temperature was calculated by heat balances over time. The model was validated by a detailed comparison with measured industrial data. A good agreement was obtained. The converter temperature depended on process parameters such as oxygen efficiency, molten emissivity and oxygen enrichment.

Jan 1, 2007

By Wen L. Chen

The steam coal quality is less stringent than metallurgical coal quality. The steam coal is prepared either by cleaning full size range of raw coal or cleaning coarse coal only, leaving the fine coal raw. The latter scheme is more cost competitive. It is particularly applicable to U.S. eastern soft coal where low ash coal is concentrated in fine sizes. For raw coal size separation, a recently developed Rotating Probability Screen, developed by the British Coal Board, may be advantageously used for easy change of raw coal separating size and to avoid screen deck plugging when handling wet and clayey raw coals.

Jan 1, 1983

By William P. Shinn

IT seems proper to present in the Transactions of the Institute, from time to time, formal record of the advances made in the arts and sciences to which our organization is devoted-milestones in the highway of progress-from which our successors may measure what they in their turn have gained. The admirable address of the Hon. Abram S. Hewitt, then president elect of the Institute, on "A Century of Mining and Metallurgy in the United States," read at the opening of the meeting held in this hall in June, 1876, forms a point of departure, and the conclusion of the eighth decade of the nineteenth century and the end of the first five years of our country's second century seem to offer a fitting time for again making up our record. The period since 1875 has been marked by a degree of activity in mining and metallurgical industry never before equalled in our history, while the progress made in the science and art has been, if possible, still more noticeable. Whether we consider the mining of iron, ore, and coal, or of the precious metals,-the advances made in smelting the former and in reducing the latter, the extraordinary increase in the production of Bessemer steel, or the science of Thomas and. Gilchrist, which makes the hitherto rejected phosphorus the corner-stone of success,-the past five years are alike memorable for the progress they have shown and to some of the most marked features of this progress I will now oriefly call your attention. It may be of interest in this connection to note the following figures, showing the growth of the population of the United-States during the last three decades :

Jan 1, 1881

By Robert M. Dreyer

In an industrialized nation, as the process of industrialization continues, the ratio of the value of production of non-metallic to metallic minerals normally increases gradually over a period of years. For example, in the United States, the ratio of the value of production of non-metals to metals now is approximately two-to-one. Those of us who come from California like to think that we inherit the mantle of the old hard-rock miner, but the truth of the matter is that, in California, of the total value of mineral production exclusive of fuels, 97% comes from non-metallic - industrial - minerals. Since the industrial minerals furnish a principal source of raw materials for the construction and chemical processing industries and since these two industries, in industrialized nations, generally increase directly with increasing population, the future of industrial mineral production both in the United States and throughout the world is indeed bright. Because of the importance of industrial mineral production, it often surprises those of us in the industrial mineral industry to find that industrial minerals are poorly understood by many of our colleagues in the mining industry. I think that one reason for this comprehension of the industrial mineral industry is that the education of both geologists and mining engineers still markedly emphasizes exploitation of the metals.

Jan 1, 1964

By J. Laganiere

A considerable part of the sulphuric acid requirements of the Aluminum Company of Canada's Arvida smelter comes from the burning of 180-200 tons per day of zinc '"'sulphide concentrates in a 22-ft.-diam-eter fluidized bed roaster. The plant and its operation were fully de-scribed in a publication that appeared about ten year ago (1). A simplified flowsheet of the roasting and gas-cleaning sections of the plant is given in Figure 1. The wet zinc sulphide concentrates are un-loaded into a pug mixer, by means of a Pay loader, and mixed with water in a mixing tank to make a slurry of 80 per cent solids. The slurry is transferred to a .feed tank and then introduced into the roaster at a point four feet above the constriction plate, which is the height of the settled bed of zinc calcines. The roasting temperature is con-

Jan 1, 1963

By Zhou Yucai, Zhou Jing, Zhu Yimim

"In this article, research on the beneficiation process for a carbon containing copper-molybdenum deposit in Henan province has been carried out. The elemental composition, mineral composition and relative content, characteristics of embedded and symbiotic relationship, the forms of the copper-molybdenum particlesand their disseminated features, and particle size distribution have been worked out. Flotation behavior of copper-molybdenum mixed flotation and separate flotation in the systems of different collectors and depressants, and the influence of different flowsheets on the copper-molybdenum separation have been investigated by actual ore flotation tests, The separation problem of copper-molybdenum for a carbon-containing copper molybdenum ore has been solved.INTRODUCTION In this paper, technological mineralogy, small experiment of flotation recovery of copper Molybdenum ore, and expansion experiment of mineral recovery of copper Molybdenum ore are introduced. (1) The results of process mineralogyshow that the content of copper is 0.42%, molybdenum is 0.021% in the raw ore, they mainly exist in the form of sulfide, with low oxidation rate. (2) The results of flotation tests show that the combination of butyl xanthate and isopropyl ethylthionocarbamate reagents is effective collector of copper-molybdenum mixed flotation for carbon copper molybdenum, (3) When the grinding fineness is -0.074 mm taking 71%, and regrinding fineness is -0.038 mm taking 85%, the flowsheet of first copper-molybdenum mixed flotation and then regrinding rough concentrate and last separation flotation of copper and molybdenum was adopted, which realized the effective separation of copper and molybdenum for carbon-containing copper molybdenum ore. Good flotation indexes were gained with copper concentrate containing 20.96% copper and copper recovery 90.06%, and molybdenum concentrate containing 46.78% molybdenum with molybdenum recovery 72.68%. (4) The seven days average concentration index of scale-up the continuous dressing experiment is as follows, the copper content in copper concentrate is 20.16% and the recovery is 89.61%; the molybdenum content in molybdenum concentrate is 24.58% and the recovery rate is 74.09%."

Jan 1, 2018

By David J. Forrester

Light metals, most commonly aluminum, magnesium and titanium, and alloys containing them, are used in many industrial applications where lightness, hardness, ductility and resistance to corrosion are needed. However, these metals and their alloys can be potential ignition sources in underground coal mines. There have been documented cases in the past where coal mine explosions have been attributed to firedamp/coal dust ignitions involving light metals or their alloys. When light metals and their alloys are brought into contact with oxygen bearing material, such as iron oxide (rust) in the presence of heat, then a "thermite" reaction can occur. This source of heat can be generated from frictional contact or from merely a glancing blow. This paper outlines the hazards associated with light alloys, how to address the hazard and regulatory aspects.

May 1, 2001

By Z. Smieszek, Z. Szota, P. Gajowski

"A new method for measuring the total quantity of suspensions contained in the electrolyte during copper electrorefining has been developed by the Institute of Non-Ferrous Metals, Gliwice. Electrolyte purity, and the suspensions content in particular, is of essential importance for the quality of electrolytic copper produced during the process. Suspensions contribute to the increase of slime impurities in electrolytic copper and increase losses in noble metals. Up to now, the laboratory method has been used for the· process control which provides analytical results with considerable time delay. Therefore, it is useless for the process control.The measuring method developed enables continuous measurements of a suspensions content directly within the stream of the flowing electrolyte. The principle of measurement is based on changes in optic properties of the electrolyte with varying suspensions content.1. IntroductionIn copper electrorefining, it is essential that the final product quality be maintained. If suspensions are present in electrolyte, the content of slime impurities in electrolytic copper, (such as Pb, Ag, Bi, Sn, Sb, and As), increases which can result in the occurrence of the so-called slime dendrites on cathodes, thus debasing the quality of the product. As a normal suspension content in electrolyte, the contents in the order of several mg/l are considered, usually not more than 5-6 mg/l, while contents exceeding 20 mg/l are referred to as an alarm state. Suspensions present in an electrolyte are usually a light fraction of anodic slime whose main components are metallic silver, lead sulphate, complexes of antimony and arsenic, and sometimes even calcium sulphate; they are mainly composed of very small particles of lead sulphate and antimony complexes. Sometimes - - in case of alarm states - - the so-called ""wandering slims"" can be observed, which are composed mainly of arsenic and antimony complexes. These ""wandering slims"" make a serious technological disturbance. In normal operating conditions of the electrorefining plant, an increase of suspension content can result from such reasons as crack of filter cloth in a slime filter, turbulent flow of the electrolyte, anodic passivation, aeration of the electrolyte, and improper servicing of an electrolytic tank. It is necessary to continuously control the suspensions content in electrolyte for proper electrorefining."

Jan 1, 1989

By Byung-Su Kim

The recovery of elemental sulfur from sulfur dioxide has important implications for coal- burning power plants and nonferrous metal smelters. The thermodynamic analyses showed calcium sulfide to be suitable for recovering elemental sulfur from sulfur dioxide. At the temperatures of 1023 to 1153 K under the sulfur dioxide partial pressures of 5.0 - 60.1 kPa, elemental sulfur from sulfur dioxide was recovered by its reaction with calcium sulfide. The kinetics of this reaction were measured at the same conditions using a thermogravimetric analysis technique. This reaction scheme would be attractive if the coproduct calcium sulfate can be reduced to regenerate calcium sulfide. This is the topic of another paper. At 1073 K under the sulfur dioxide partial pressure of 25.8 kPa, 48 % of the original calcium sulfide was converted to calcium sulfate in an hour. Under the same conditions, 55 % of the regenerated calcium sulfide were converted to calcium sulfate in an hour even after third regeneration.

Jan 1, 1999

By O. D. Maurice

Feldspar mining in Canada came to an end during 1972 after many years of continuous activity. The deposits are not exhausted and the domestic demand for this product is expected to continue at about the same level as in recent years. The size of the industry does not justify the installation of expensive equipment in the mills, but it is believed that a modest profit could be made by a small operation using rudimentary methods of separation. Largescale and accurate mapping of the pegmatite dykes could help in planning mining operations for a better recovery of a uniform product.

Jan 1, 1973

By C. M. Iheagwara

This paper has addressed the issues that constitute major obstacles to the cost- effective and efficient operation of metallurgical vessels from the refractory standpoint. Refractories generally withstand severe conditions of high temperature reactions as well as physical loading/impingement and hence degenerate and need replacement. Scarcity of some refractory materials especially high alumina and magnesite ores in some places, the prohibitive cost and the frequency of replacement of damaged refractories threaten the continued support for metallurgical operations. Some of the causes, prevention and cure for refractory wear have been discussed and rational strategies (short and long term) have been recommended which if implemented should go a long way towards arresting the perennial problems they portend.

Jan 1, 1991

By Shinji Muraishi, Shinji Kumai, Yasutaka Kedo, Takashi Kambe

"Magnetic pulse forming (MPF) is one of the extreme high-speed forming processes. A metal sheet which is accelerated by electromagnetic force is collided onto a mold and fine and sharp details of the product can be obtained. The deformation mechanism of the MPFed metal cannot be understood only by the microstructure observation of the deformed metal. The deformation behavior of the metal should be investigated also by considering the local microstructure change with strain, strain rate and temperature change during deformation. Numerical analysis is an effective method to achieve this requirement. In this study, pure Al and Cu sheets were deformed by MPF. Impact velocity of the metal sheet was calculated by using ANSYS Emag-Mechanical. Based on the obtained impact velocity, the deformation behavior of the metal sheet was reproduced, and local strain, strain rate, and temperature were analyzed by using ANSYS AUTODYN. The relationship between the local microstructure change of Al and Cu sheets and the deformation parameters was examined.INTRODUCTIONMagnetic pulse forming (MPF) is one of the high-speed forming processes using electromagnetic force. Fine and sharp details of the product can be obtained, and springback after deformation is extremely reduced in comparison to the conventional forming processes(Psyk, Risch, Kinsey, Tekkaya, & Kleiner, 2011). Figure 1 shows a schematic diagram of MPF. A metal sheet is placed over the coil in the discharge circuit. The discharge current runs through the coil, and magnetic fieldis producedaround the coil. An eddy current is inducedin the metal sheet. Interaction between magnetic field and eddy current creates electromagnetic force. The metal sheet accelerated by electromagnetic forcecollides ontothe mold. Forming is completed in a few tens of micro-seconds.MPF is suitable for metals with a high electrical conductivity like Al and Cu.The MPFed metal may have characteristic microstructure because of high strain rate deformation."

Jan 1, 2018

By B. Zeytuncu, O. Yucel, O. H. Celik, M. H. Morcali

"The Taguchi method was used as the experimental design to determine the optimum conditions of cementation behavior of the ruthenium chloride solution. Cementation was carried out using metallic zinc powder. The experimental conditions were studied in the range of 25-45°C for reaction temperature (A), 30--60 min for reaction time (B), 0.5-1.5 for pH of solution (C), and 30--50 mg for zinc powder (D). Experimental parameters and their levels were determined in the light of preliminary tests. Orthogonal array (OA) L9(34) consisting of four parameters each with three levels, was chosen. The optimal conditions found for ruthenium, such as a reaction temperature, reaction time, pH of the solution and mass of zinc, are respectively: 45°C, 45 min, 1.5 and 50 mg. Under these conditions, the ruthenium cementation efficiency obtained by theoretically and experimentally was in good agreement, which were 99.8% and 99.7% respectively."

Jan 1, 2013

By Douglas Silver

During the past decade, Latin America has commanded an ever growing percentage of the world’s mineral exploration expenditures. Today, it controls approximately 30%. This has led to an increased number of large and small mineral discoveries over prior years for a variety of metals and the construction of many new mines. Its dominance is also seen in the larger than expected share of international mining capital investment. This has given its workers a competitive edge in global terms and an expertise that will ensure a long-term longevity to its mining industry. The best incentive for making vestment decisions is success. In this regard, Latin America’s success has compounded the incentives for further investment. Despite the large amount of foreign investment in Latin America, the wealth of these nations is not merely in its geological potential. The reason that several Latin American countries rank as global leaders in metal production is strongly influenced by their development of a strong mining culture, a culture which has been cultivated over many centuries. Good business practices provide another strong attraction to these regions. Additionally, Latin Americans have strong scientific and technical expertises. This is seen both in the investments’ size and the preference for high domestic employment. Relative to the number of domestic miners, the number of expatriates operating in Latin America is only a token few. In essence, the world markets are investing into the local geology and people.

Apr 24, 2001

By Keenneth Huachaca

Durante los últimos años, en las operaciones mineras subterráneas surgió la necesidad de contar con diversos mecanismos de control operativo orientados a la mejora de los procesos productivos. Actualmente estos mecanismos tienen muchas dificultades, principalmente en las comunicaciones, debido a la volatilidad de las labores, costos altos de instalación y daños físicos a los medios de comunicación existentes (fibra óptica, cables coaxiales y leaky feeder), lo que dificulta principalmente la extracción de datos de los equipos móviles livianos y pesados. En este trabajo se presenta un nuevo medio de comunicación que se adapta a la volatilidad de las labores mineras, tiene bajo costo de instalación y está exento de sufrir daños físicos en su trayecto, por lo que garantiza una alta disponibilidad y fiabilidad de la transferencia de información del subterráneo hacia los centros de control existentes, donde la información es procesada, a la vez que facilita la aplicación de los mecanismos de control para la optimización de los procesos productivos.

Sep 20, 2019

By Martin B. Schranz

Copper sulfate pentahydrate is recovered from the spent etchant waste stream of a printed circuit board manufacturing facility by cooling crystallization. The fluidized bed crystallizer contains submerged cooling surfaces which are bathed in a stream of air. The air bubbles provide agitation which improve heat transfer, reduce fouling and maintain crystals in suspension. The recently patented apparatus (US 5,523,064) has advantages when compared to a conventional surface cooled crystallizer including capital cost, ease of operation and production of larger more uniform crystals

Jan 1, 1997