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By Duberney Hincapié-Ladino

O presente trabalho estuda os parâmetros de permeabilidade de hidrogênio de um tubo API 5L X80, e uma chapa de aço grau X80, onde a principal diferença está na composição química, o primeiro contém 0,07%C e 0,04%Nb e o segundo 0,04%C e 0,102%Nb. As amostras foram cortadas com espessura de aproximadamente 1 mm, lixadas e recobertas com um filme de níquel, em uma das faces. Nos ensaios de permeabilidade foi utilizada uma célula modificada tipo Devanathan-Stachurski, com a solução A da norma NACE TM0284, com injeção de H2S no lado de geração e 0,2M NaOH no lado de detecção. As curvas de corrente em função do tempo obtidas passaram por tratamentos matemáticos (método tlag), permitindo a obtenção dos parâmetros de difusividade aparente, concentração máxima de hidrogênio e número de traps (sítios de ancoramento). Tais parâmetros mostraram-se iguais para os dois materiais. As curvas foram normalizadas e modificadas de maneira a eliminar o efeito da espessura das amostras. Estas novas curvas foram comparadas com o modelo teórico da segunda lei de Fick. A comparação evidenciou que o procedimento inicial para a obtenção dos parâmetros de permeabilidade mostra-se eficiente e vantajoso por apresentar maior praticidade. Pôde-se concluir que a semelhança no comportamento dos parâmetros de permeabilidade foi devida às similaridades nas suas microestruturas. Os resultados obtidos no presente trabalho evidenciam que o tipo e quantidade de traps nestes materiais são determinados pela microestrutura.

Aug 17, 2017

By Fermont F. Clarke, Others, Paul Zinner

"INTRODUCTION The Edison mine comprises workings on two irregular spodumene-bearing pegmatite dikes which outcrop near the town of Keystone in the southern portion of the Black Hills of South Dakota. The Bureau of Mines conducted an investigation of the Edison mine as part of a comprehensive study of the lithium mineral-production possibilities in the Black Hills area. The work was undertaken during the Second World War, when the demand for certain lithium salts and compounds exceeded the then small productive capacity of the industry.During the course of the project, the Bureau of Mines completed 13 diamond core-drill holes, aggregating 2,114.5 feet of drilling. Twenty-six cannel samples were taken from the main Edison shaft, and 13 miscellaneous samples were obtained to permit analysis of the efficiency of phases of mining and sorting operations. Metallurgical tests were made by the Bureau of Mines to investigate the feasibility of beneficiating spodumere-bearing ores from the Edison mine. 3/"

Apr 1, 1948

By G. W. Weems

The Bureau of Mines used the Burnett method and apparatus to determine the compressibility factors for helium and carbon dioxide mixtures at 0°, 10°, 20°, 23°, and 35° C and to pressures of 900 psia. Tables of compressibility factors and approximations of the virial coefficients are presented for seven binary mixtures as well as for helium and carbon dioxide. The results compare favorably with existing data.

Jan 1, 1969

By Diogo Barcellos Moraes

O presente trabalho tem como premissa abordar estudos baseados na metodologia Troca Rápida de Ferramentas (TRF ou em inglês, SMED – Single-Minute Exchange of Die), e realizar um estudo de caso na empresa Votorantim Siderurgia. O objetivo principal é a redução do tempo de setup da máquina de Tela de Coluna, a fim de minimizar o desperdício de tempo e maximizar a produtividade. Além disso, obteve ganhos efetivos no layout de ferramentas, programa 5S, tempo de atividades, entre outros.

Oct 30, 2017

By S. J. Thomas, P. A. Lilly, J. A. L. Napier

An industry research project has been established to examine the issue of rock mass failure in large open pit slopes. The approach began with numerically modelling failure at the laboratory scale with a displacement discontinuity program. The interim results from the program suggest the output failure mode is dependent upon the input parameter cohesion weakening. Es wurde ein Forschungsproject mit unterstützung von Bergbauindustrie bearbeitet. Die Zielsetzung der vorliegenden Arbeit war die Analysierung des Böschungsgefähr im größen Festgesteinstagebauen. Das Verfahren besteht aus der numerischer Modelierung mit Ansatz einen sonderen Rechnerprogram. Die erste Ergebnis zeigt, daß die Aufgabe am Angabendaten (cohesion) abhängig sein wird. Un project de recherche industriel fût conduit avec le but d’examiner les éboulements de roche dans les mines a ciel ouvert. La premiere étape a été de modelliser numériquement les éboulements dans un laboratoire en utilisant un programme de déplacement discontinu. Les resultants préliminaires du programme indiquent que la prédiction des ébouliements est directement reliée à la magnitude de la cohesion.

Jan 1, 2003

By Meguru Nagamori

DURING the smelting of the sulfide ores of copper, nickel, and certain other metals, a matte phase is formed. For a better understanding of the physico-chemical properties of mattes, binary systems such as Cu-S, Ni-S, Fe-S, and so forth, should be studied, especially in the vicinity of liquid compounds such as Cu2S, Ni3S2, FeS, and so forth. These compounds are relatively stable in the solid state although they can exhibit appreciable deviations from stoichiometry. With small deviations from stoichiometry there are large changes in the activity of both sulfur and metal this is a characteristic of both solid and liquid sul-fides near the stoichiometric compositions. In the vicinityof molten Cu2S,1 for instance, the activity of sulfur increases about 100 times for a 0.012 increase in the mole fraction of sulfur and, correspondingly, the activity of copper decreases greatly. In this sens the minor deviations from stoichiometry should be carefully taken into account in studies of such metal-sulfur melts. Metal-sulfur melts may be considered to have properties intermediate between metallic solutions and molten salts, i.e., neither entirely metallic nor entirely ionic. The radius of the ion sZ- is 1.84 as compared with 1.04? for a single bond covalent s.2 It is therefore inferred that when the sulfur is more ionic its partial molar volume is larger, although metal-metal, metal-sulfur, and sulfur-sulfur interactions may bring about further complexities. Thus, it is to be expected that the molar volumes, which are derived from density-composition relations, will help in resolving the structure of the melts. In this study the maximum bubble pressure method with bubbling gases of H2, H2S, and Ar, .was employed to measure the density. EXPERIMENTAL Materials. Silver of 99.95 pct purity was melted in an alumina crucible and hydrogen gas was then bubbled through the liquid for the deoxidation. In preparation of Cu2S, electrolytic copper powder (>99.9 pct Cu) was mixed with precipitated sulfur and heated to 1200°C in an alumina crucible under a hydrogen atmosphere. Mixtures having the approximate compositions FeS and Ni3S2 were prepared by heating reagent grade electrolytic iron or reduced nickel powder with precipitated sulfur under a hydrogen atmosphere. The H2S gas was of 98.5 pct purity, the impurities being mostly CO2 and CS2 which hardly contaminate the melts. Apparatus. The crucible system is shown schematically in Fig. 1. To minimize the variation of melt composition during a density measurement, the apparatus was designed in such a way that either Ar, H2, H2S, or mixtures of these gases could be used as the bubbling gas. When the melt had a high partial pressure of sulfur, H2S gas was used. When the partial pressure of sulfur was so low that oxygen might dissolve in the melt, the use of H2 was preferred. In intermediate cases, argon or mixtures of H2-H2S were used. Density of Dibutylphtalate. Dibutylphtalate was used as the manometer fluid. Relative to distilled water, the density of the dibutylphtalate, pdib g per cc, was measured and found to be: pdib (25°C) = 1.046 i 0.002. With the use of the temperature coefficient reported by Kemppinen and Gokcen,3 the following value was

Jan 1, 1970

By H. E. Hilliard

A method was investigated for detecting and counting filamentous iron bacteria in open recirculating cooling systems. It is simple and fast and does not require trained microbiologists. Samples from 26 systems were examined. Cells were cultivated on commercially prepared ready-to-use media. Cultures grew well on this medium and were identified as filamentous iron bacteria by microscopic examination and by their ability to deposit iron using the prussian blue reaction.

Jan 1, 1976

By E. F. Ferrell

Electrowon molybdenum powders and a commercial hydrogen-reduced powder, all with different minor impurities, were investigated by the Bureau of Mines with respect to inherent properties, to fabrication techniques, and to proper-ties of the fabricated sheet. Compared with the commercial hydrogen-reduced powder, the electrowon powders had a larger particle size, a greater flow rate, a higher apparent density, and a lower oxygen content. Sheet materials prepared from the two types of powders showed similar mechanical properties, under the same conditions of heat treatments, except for low-temperature ductility. Yield strengths varied with carbon content, heat treatment, and test temperature.

Jan 1, 1970

By G. F. Kuncir

The analysis described herein evaluates the Bureau of Mines Program for Advancing Mining Technology - Oil Shale in terms of the economic benefits which may be derived for the Nation as a result of its successful research and development efforts. On the basis of postulated oil shale production scenarios, benefit-cost ratio indicators are computed for the program elements as they apply to surface, underground, and modified in situ oil shale mining systems. Eight value indicators are used to measure the Program's beneficial impact on the future oil shale industry in relation to planned research and development costs. These are: capital cost savings, operating cost savings, labor savings environmental quality maintenance cost reduction, reduction in production costs, byproduct production benefits, total production benefits, and additions to recoverable reserves. Program costs are aggregated from 1974 through 1987 and major benefits are accrued from 1982 through 2040. Both cost and benefit streams are discounted to mid-1975 present value.

Jan 1, 1977

[Arizona BRENT N. RICHARD, Chairman ROBERT W. HUGHES, Vice-Chairman ROBERT E. S. HEINEMAN, Secretary-Treasurer Arizona Bureau of Mines, University of Arizona, Tucson, Ariz. THOMAS G. CHAPMAN A. MENDELSOHN WILLIAM KOERNER A. C. REIFSNIDRR C. R_ . KUZELL WILLIAM M. SABEN ERNEST WITTENAU Black Hills NATHANIEL HERZ, Chairman C. E. DAWSON, First Vice-Chairman BANCROFT GORE, Second Vice-Chairman C. E. SCHMIDT, Secretary-Treasurer Homestake Mining Co., Lead, S. D. R. S. BLITZ NATHANIEL HERZ C. E. DAWSON A. I. JOHNSON L. B. EAMES F. C. LINCOLN BANCROFT GORE C. E. SCHMIDT]

Jan 1, 1940

By J. H. East

"INTRODUCTION .Very little information regarding coal mining in Spain has been published in the American technical press, and few people realize the extent of this industry or the conditions under which coal is mined. The information in this publication was collected in 1945 and consists of personal observations in Spain, statistics, and other data of a, general nature obtained from official sources.Spain produces bituminous coal, lignite and anthracite, but the total tonnage mined is less than the national requirements. Before the war, an appreciable tonnages coal was imported from Great Britain under the Anglo-Spanish treaty, which rebated import duties and effectually prevented competition from any other foreign source. The war stopped the major part of the important of British coal and caused rapid expansion of the domestic sources, but this was not sufficient to supply the industrial demand. Coal that formerly was not acceptable to industry because of quality is now mined and marketed. The Government, allocates the better-grade bituininous coal to the various industries in accordance with the national importance of the work in which they are engaged; for example, the railroads are allotted 100 percent of their requirements, but cement companies can obtain only 25 percent.The Government offered to inducements to increase the production of coal of any class, but the larger part of the increased tonnage obtained was in inferior grades; as a result, the lignite production was taxed, while a bonus was paid for bituminous-coal production in excess of the 1942 tonnage.The anthracite and bituminous-coal areas were severely damaged during the Civil War and many experienced miners migrated to the lignite mines in eastern Spain. This has resulted in an acute shortage, particularly the Province of Oviedo where the most important bituminous-coal deposits are located."

Jan 1, 1947

By Jaime Tumialán

El presente texto describe el diseño y ejecución del sistema con winchas de fricción" Koepe" del pique central de Casapalca, dado que será uno de los más modernos del Perú y su aplicación se realizará en minas con características semejantes. Existen dos sistemas básicos de izaje: el de izaje con wincbas de tambora, donde el cable es enrrollado o desenrrollado en la tambora durante el izaje, y el de izaje con wincbas de fricción ("Koepe"), en el cual el cable pasa sobre la polea o tambora de fricción durante el izaje. Cada sistema tiene sus ventajas y desventajas y solo debe usarse en una correcta aplicación. Las principales ventajas de las winchas de fricción sobre las de tambora son: menor consumo de energía para igual capacidad, menores dimensiones de las partes mecánicas, menor costo de capital y operación, mayor seguridad debido a que se usan varios cables y una mayor capacidad a grandes profundidades.

Jan 1, 1983

By Scott G. Britton

Mine exploitation is a broad subject whose focus is the technical skills or efforts needed for the extraction of mineral from a known ore body. Mine exploitation can be considered the very core of the mining engineering discipline. It begins at the conclusion of the exploration and development stages of mining and ends when the ore body is exhausted and the mine (or mines)closes and is reclaimed. Section 8 on mine exploitation is comprised of seven chapters: (1) classification of mining methods, (2) mine surveying and mapping, 3) systems engineering, (4) computer methods, (5) labor relations and training, (6) management and administration, and (7) mine closure, sealing, and abandonment. Each chapter focuses its efforts towards providing detailed and useful information for the engineer on basic mine exploitation principles. The information can be applied to a broad range of mining problems without regard to mineral type or mining method.

Jan 1, 2008

By AIME AIME

THE twenty-second annual meeting of the Canadian Mining Institute was held at the King Edward Hotel, Toronto, on Mar. 8, 9, and 10, and was followed on the 11th by an all-day excursion to the International Nickel Refinery at Port Colborne. The meeting was very well attended and dealt with some of the most important matters, both technical and economic, that have ever come before the Canadian Institute. The question of licensing engineers is before the Canadian members as it is before our own in this country and the attitude of the mining engineers across the border is like that of the American mining engineers, opposed to the licensing of the mining. engineer, however they may feel toward the licensing of other branches of the engineering profession. It was well pointed out that such a law, had it been in existence in the last decade or two, would probably have prevented the rapid development of Canada's mines. Whereas one civil engineer can run a line of survey as well as another, perhaps, it is only a question in his case of whether he can or cannot survey. In the case of a mining engineer employed by a man with capital to invest in a development project, unless the man with the money has confidence in the judgment of his engineer the fact that he is a professional man would carry little weight in inducing a large investment toward the development of Canada's resources. It was also pointed out that although the Institute as a whole had not passed on the matter, it would probably be opposed to legislation aiming only for self-interest, but would be heartily in accord with legislation which could be shown to be for the service of the community at large.

Jan 1, 1920

By H. H. Heady

This Bureau of Mines report provides specific information regarding the analysis of ores, concentrates, and bullion. It describes analytical services provided by some Federal agencies, and discusses analytical techniques applicable to the precious metals. The appendixes list Bureau of Mines State Liaison Offices and commercial assay laboratories.

Jan 1, 1976

By S Wright, W Bruckard

The current status of battery collection and recycling schemes in Australia are explored in light of current developments in product stewardship and increasing pressure to decrease materials going to landfill by originating equipment manufacturers. Used consumer batteries, both single cycle and rechargeable contain a mixture of valuable metals and potentially toxic materials that may become a resource/revenue stream to offset the cost of disposal/recycling. Although the volume of batteries discarded in Australia is modest compared to other global population centres, the expected increase in battery use with increasing equipment portability and future developments in the automotive industry, provide an opportunity to recycle. The requirements for a battery recycling facility in Australia and the most promising processing platforms that may exploit the resource with enough flexibility to cope with battery developments and market trends, are explored.

Jan 1, 2006

By Jerry C. Tien

China?s remarkable levels of economic growth during the past three decades have lifted almost 300 million people out of poverty. This amazing achievement has placed an increasing demand on energy and minerals, especially coal, which supplies 68.7 percent of China?s energy (June 2011). It is estimated that China mined more than 3 Gt (3.3 billion st) of coal in 2010, three times as much when compared to merely 10 years earlier. Such an impressive achievement does not come without major costs ?? including concerns with mine safety and an increasing number of occupational illnesses due to fast growth. This article reports on one of the major safety concerns in China?s coal mining, dust and dust control practices, and known cases of caol worker?s pneumoconiosis affiliated with prolonged exposure to excessive coal dusts. The exact size of China?s mining industry is not known, but it is estimated the coal industry is at least five-million people strong, and the metal and nonmetals industry probably employs another three million people. To meet increasing energy demand, China mined more than 3.1 Gt (3.4 billion st) of coal in 2010 from its 15,000 plus coal operations1, most of which are small- to medium-sized operations with annual coal productions ranging from a few thousand tons to 300 kt (330,000 st). These small coal operations are typically in remote areas, inadequately engineered, poorly ventilated and still using rudimentary drilling and blasting mining methods employing antiquated mining equipment and, presenting safety concerns, i.e., methane and dust explosions.

Jan 1, 2011

By B. W. Dyer

In 1924, the Crescent Eagle Oil Co., while drilling the salt section of the Paradox formation in Grand County, Utah, encountered a salt that did not appear to be sodium chloride. This salt was analyzed and showed the presence of potash minerals, both sylvite (KCl) and carnallite (KMgC12.6H2O). Because of the high potash content of the sample, there was considerable speculation: (I) as to whether the hole had been salted, and (2), if not, the extent, richness, and the depth at which the deposit occurred. The discovery caused a large amount of activity in the area. During the next few years, 68 potash prospecting permits were issued by the Government, 24 under the Act of 1917 and 44 under the Act of Feb. 7, 1927, each including about four sections of land. Several holes, all shallow, were drilled for potash. A number of holes were drilled for oil into the salt horizon and the cuttings collected at the oil wells were examined petrographically and chemically. The shallow test holes were not sufficiently deep to reach the potash horizon and revealed nothing of value, but several of the oil test holes gave some indication of where potash might be found. Location and Geology of Deposits The potassium and magnesium salts have been found in various places from the Denver and Rio Grande Western Railroad tracks about seven miles west of Thompsons, in eastern Utah, to Cane Creek, a tributary of the Colorado River— a distance north and south of about 35 miles. In this locality, there appear to be five separate deposits: the Crescent Eagle area, which is in T. 22 S., R. 19 E.; the Salt Valley area, in the vicinity of the north-south line of T. 23 S., between R. 20 E. and R. 21 E.; the Seven Mile area, in the eastern part of T. 25 S., R. 20 E.; the Cane Creek area, on the Colorado River, in T. 26 S. and T. 27 S., R. 20 E. and R. 21 E.; and the Salt Wash area, in T. 22 S. and T. 23 S., R. 16 E. and R. 17 E. (Fig. I.) The Crescent Eagle and Salt Valley areas are in the Salt Valley anticline, some of the wells being in the fault graben and others outside. Structurally, the Salt Valley anticline is very complex, and can be described in general terms as a northwesterly plunging collapsed anticline about 15 miles long. In the Crescent Eagle area, the valley graben is about 1 1/2 mile wide and the salt probably forms a plug, the apex of which is in the vicinity of the Crescent Eagle well. Owing to the complex structure, there has been every opportunity for flowage in the salt to cause local thinning or thickening of beds. The regular succession of formations in the general area* is: Cretaceous Mancos Dakota Jurassic Morrison Summerville Entrada Carmel

Jan 1, 1948

By B. W. Dyer

In 1924, the Crescent Eagle Oil Co., while drilling the salt section of the Paradox formation in Grand County, Utah, encountered a salt that did not appear to be sodium chloride. This salt was analyzed and showed the presence of potash minerals, both sylvite (KCl) and carnallite (KMgC12.6H2O). Because of the high potash content of the sample, there was considerable speculation: (I) as to whether the hole had been salted, and (2), if not, the extent, richness, and the depth at which the deposit occurred. The discovery caused a large amount of activity in the area. During the next few years, 68 potash prospecting permits were issued by the Government, 24 under the Act of 1917 and 44 under the Act of Feb. 7, 1927, each including about four sections of land. Several holes, all shallow, were drilled for potash. A number of holes were drilled for oil into the salt horizon and the cuttings collected at the oil wells were examined petrographically and chemically. The shallow test holes were not sufficiently deep to reach the potash horizon and revealed nothing of value, but several of the oil test holes gave some indication of where potash might be found. Location and Geology of Deposits The potassium and magnesium salts have been found in various places from the Denver and Rio Grande Western Railroad tracks about seven miles west of Thompsons, in eastern Utah, to Cane Creek, a tributary of the Colorado River— a distance north and south of about 35 miles. In this locality, there appear to be five separate deposits: the Crescent Eagle area, which is in T. 22 S., R. 19 E.; the Salt Valley area, in the vicinity of the north-south line of T. 23 S., between R. 20 E. and R. 21 E.; the Seven Mile area, in the eastern part of T. 25 S., R. 20 E.; the Cane Creek area, on the Colorado River, in T. 26 S. and T. 27 S., R. 20 E. and R. 21 E.; and the Salt Wash area, in T. 22 S. and T. 23 S., R. 16 E. and R. 17 E. (Fig. I.) The Crescent Eagle and Salt Valley areas are in the Salt Valley anticline, some of the wells being in the fault graben and others outside. Structurally, the Salt Valley anticline is very complex, and can be described in general terms as a northwesterly plunging collapsed anticline about 15 miles long. In the Crescent Eagle area, the valley graben is about 1 1/2 mile wide and the salt probably forms a plug, the apex of which is in the vicinity of the Crescent Eagle well. Owing to the complex structure, there has been every opportunity for flowage in the salt to cause local thinning or thickening of beds. The regular succession of formations in the general area* is: Cretaceous Mancos Dakota Jurassic Morrison Summerville Entrada Carmel

Jan 1, 1948

By Don M. Coulter

"INTRODUCTION The Lookout Mountain coal deposits were examined by J.L. Stratton, an engineer of the Bureau of Mines in April and May 1943. The area investigated includes that part of southern Lookout Mountain in townships 4 to 8, south, ranges-9 to 11 east, and contains approximately 140 square miles in DeKalb and Cherokee Counties in northeastern Alabama (fig. 1.)Six coal seams having a minable thickness of 18 or more inches are represented in the area. The third seam, known locally as the Hill seam, has been correlated with the Upper Cliff No.1 seam and is referred to as such throughout this report. The preliminary investigation indicated that the Upper Cliff No. 1 seam is a low-volatile, high-grade coking coal. The work done on this project was confined principally to determining the amount and grade of coal in this seam.The only existing maps of mines in the area were one of the Lookout Fuel Co. at Lahusage, Ala. (fig. 2), and one of the Lookout Mountain Iron Co. at Battelle, Ala. (fig. 3), Consequently, to gain some knowledge of the grade and tonnage mined, surveys of the other mines were necessary. Many of them were caved, and many were filled with water, necessitating considerable preliminary work."

Feb 1, 1947