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By H. William Zeller

The U.S. Bureau of Mines evaluated the effects of two iron-based fuel additives on diesel particulate matter (DPM) emissions. The 5.6-L, six-cylinder test engine is typical of engines used in underground mines. One additive, ferrous picrate, did not measurably affect exhaust emissions. This report is mainly about a ferrocene-based additive that reduced DPM between 4 and 45 pet., depending on engine operating conditions. The report concludes that the DPM reductions were caused by the catalytic oxidation properties of a ferric oxide coating that developed inside the engine's combustion chamber. The ferric oxide coating also decreased gas-phase hydrocarbons and O2, but it increased CO2 and NOx, The increase in NOx, of about 12 pet, is considered the only adverse effect of the ferrocene-based fuel additive. The results suggest that the effectiveness of ferrocene was partially offset by increased sulfates because of the high-sulfur fuel used. Recommendations for continuing fuel additive research are presented.

Jan 1, 2010

The Bureau of Mines in the Department of the Interior is increasingly concerned with the safety and health of personnel engaged in coal-mining operations, particularly below ground. The Bureau is also concerned with improving the utilization of domestic mineral resources, and reducing the environmental impact of mineral operations. One obvious way to improve safety and minimize health hazards would be to eliminate coal mining entirely by bringing the energy value of the coal to the surface in some other way, such as by partially burning it underground to form combustible gases and bringing these gases to the surface, where their energy content can be put to use. This technique might also improve the utilization of the coal resource. ? Accordingly, the Bureau of Mines, interested in re-evaluating underground coal gasification technology in terms of current and expected conditions in the United States, requested Arthur D. Little, Inc., (ADL) to appraise the technology to determine: ? Whether the current (1971) state of the technology offers a technically feasible method for gasifying coal underground that is applicable to the reserves of bituminous and lower rank coals in the United States. ? Whether a program of research and further development of the technology could ultimately make it a technically feasible alternative to current open-pit and underground coal mining operations. ? What the nature and cost of further research and development work in the technology should be.

Jan 1, 1971

By S. G. Kumar, R. G. Reddy

"Niobium aluminides offer the advantage of higher high temperature capability compared to other intermetallic aluminides due to the refractory nature of niobium. However, the reaction sequence in Nb-Al system is sluggish and currently there is a great interest in the processing aspects of these materials. In the present study, a systematic investigation was undertaken to compare the effect of different powder metallurgy processing routes on the phase relations and microstructure of 66Nb-22AH2Ti (in atom percent) alloy. The three different process routes adopted were: (i) cold pressing followed by reaction sintering; (ii) cold pressing and hot pressing followed by sintering; and (iii) arc melting, hydride-dehydride process to make the alloy powder followed by cold pressing and then sintering. The samples are analyzed by XRD, Optical Microscopy, SEM-EDS and EPMA. The analysis showed that alloy pellets made from pre-alloyed powders i.e., arc melting followed by hydride-dehydride process, gave good densification and more Nb3Al formation.1. IntroductionTo improve the performance standards of turbine engines, materials scientists are challenged to develop materials that have· high thrust-to-weight ratio with high specific strength, high specific modulus and good environmental properties at elevated temperatures. The conventional high temperature materials like nickel based superalloys are high in density and hence many of the high temperature materials scientists have focussed their attention on intermetallic aluminides like Fe-AI, Nb-AI, Ni-AI and Ti-AI in recent years. The phase relations and properties of alloys based on Fe-AI, Ni-AI and Ti-AI are fairly well known whereas little is known about the alloys based on niobium aluminides."

Jan 1, 1996

By W. E. Robinson

Oil-shale kerogen was processed into oil and oil products before the first oil well was completed by Drake in 1859. However, because of economic and other advantages, natural petroleum has been the principal source of liquid fuels and lubricants since 1859 and is a convenient root of many [organic] chemicals in common use today. In recent years the difference has narrowed between the cost of producing liquid fuels from well petroleum and other sources. This narrowing of cost difference has resulted both from the increased cost of finding new sources of petroleum in the United States and the experimental demonstration of lowered costs for synthetic liquid fuels by the Federal Bureau of Mines and by industry. Available petroleum resources of this country are being reduced and eventually may be inadequate to meet the demand. Alternate means of assuring an adequate supply of liquid fuels for this country include the development of processes for utilizing other carbonaceous materials such as oil shale and coal.

Jan 1, 1960

By T. E. Wilson

The length of Alaska's coastline, combined with the presence of a significant number of fjords, encourages consideration of marine disposal of mine tailings. However, the decision-making process is complex because various factors govern the viability of the submarine tailings disposal (STD) option. An expert system, called the Submarine Tailings Disposal Expert System (STADES), was developed to help mining project planners explore the feasibility of STD. A review of the existing literature, supplemented by engineering recommendations, on the various aspects of the marine disposal of tailings formed the knowledge base for the expert system. The shell used to develop the expert system was LEVELS.

Jan 1, 2003

By Omero Alonso-Gonzalez, Sergio Haro-Rodriguez, Ricardo Solis-Rodriguez, Francisco Alvarado-Hernandez, Juan Antonio Gonzalez-Anaya, Héctor Rene Vega-Carrillo

"Precious metals are currently associated with refractory minerals such as telluride (Calaverite, Sylvanite, etc.) and selenium (Naumannite Ag2Se), which are difficult to dissolve through traditional methods, therefore it is necessary to perform a pretreatment (oxidative or roasting) preceding the process of leaching by cyanidation. In this preliminary work the aim was to study the use of solvent extraction to remove tellurium and selenium ions from a synthetic cyanidation effluent, with the purpose of recycling the cyanide back to the process. For the extraction of these anions, TeO32- and SeO42-, tallow trimethyl ammonium chloride (Quatarmina TPR) and hexadecyl trimethyl ammonium chloride (Amine F) were studied as extractants, using nonylphenol as a modifier in the organic phase (trimethylpentane). The results show that it is possible to recover 82% of selenium and 10% of tellurium from synthetic solutions containing either 20 mg/L Se or 20 mg/L of Te, respectively The Se or Te mole ratio to cyanide was 1:4.INTRODUCTION In relation to extraction of precious metals, the cyanidation process has been in use for over a century and despite environmental and toxicological problems it remains the most widely used and economical process available. In the late 90s, there were great efforts to recover gold and silver from refractory ores, which is difficult to do by simple cyanidation. To improve gold recovery from tellurides and selenides that occurs in some new mines, the ores are pretreated by roasting. This is one of the most effective ways of rendering refractory gold ores leachable as well as being a fast pretreatment process compared with bio-oxidation or pressure leaching (Aylmore, 2001). The most important tellurides minerals are Calaverite (AuTe2) and, Silvanite (Au, Ag)2Te4). In the case of selenides, minerals include Naumannite (Ag2Se) and Aguilarite (Ag4SeS) (Ostroumov et al., 1989). Examples of deposits containing telluride include La Bambolla Mine (Sonora, Mexico), Cripple Greek (Colorado, USA), and Kalgoorlie (Western Australia) (Aguayo et al., 1996). The main purpose of this work was to explore the feasibility of using quaternary ammonium salts such as: tallow trimethyl ammonium chloride (Quatarmina TPR) and hexadecyl trimethyl ammonium chloride (amine F) to extract tellurium and selenium anions from aqueous synthetic cyanidation effluents, so that the cyanide solution could be recycled back to leaching process. The tests were performed on synthetic solutions similar to those found in a mine: 20 mg/L Te as TeO32-, 20 mg/L Se as SeO42- and mole ratio to cyanide was 1:4. using an alkaline medium with pH ranging from 8 to 12. Two aspects are evaluated in this paper:"

Jan 1, 2017

By James Westfield

This report covers the calendar year 1953 and has been prepared and submitted in accordance with the provisions of Sec. 106(a) and Sec. 212(c) of the Federal Coal Mine Safety Act (66 Stat. 692; 30 U.S.C. Secs. 451-483). During this first full calendar year of operations under the Federal Coal Mine Safety Act, the coal-mining industry of the United States attained the best injury records in its history - improving the former best records (made in 1952) by 91 fatal and 10,020 nonfatal injuries. Whereas, the mandatory provisions of the act were intended and designed to prevent major mine disasters, apparently the effects have reached beyond the scope thereof in reducing mine accidents generally.

Jan 1, 1954

By Rafael Lopes

O rendimento metálico é um dos principais indicadores de processo de laminação de longos, uma vez que tem influência direta na redução do custo de produção, sendo fundamental no atual cenário econômico da siderurgia brasileira. Em função disso faz-se necessário identificar as principais causas de perdas metálicas para aumentar o índice desse indicador, utilizando a metodologia DMAIC. Como resultado houve o aumento de 1,22% alcançado pela otimização dos parâmetros de processo do tratamento térmico, redução do comprimento do descarte da cabeça e cauda da barra na tesoura e melhoria na automação das válvulas do sistema de têmpera e autorevenido.

Aug 17, 2017

By Leandro Augusto Justen Marzulo, Guilherme Lucio Abelha Mota, Otávio da Fonseca Martins Gomes, Gilson Alexandre Ostwald Pedro da Costa, Alexandre da Costa Sena, Felipe Schimith Batista

O presente trabalho desenvolveu uma solução, utilizando Hadoop e Map Reduce for C (MR4C), capaz de paralelizar a segmentação de fissuras em imagens de partículas minerais. Um conjunto de 221 imagens de tamanhos distintos de partículas de minério de cobre obtidas por microscopia eletrônica de varredura foi utilizado para os testes. A variação do número de nós de processamento apresentou um ganho do tempo de execução que escalou de forma quase que linear. O balanceamento de carga estática promoveu um speedup de 1,3. A solução proposta, quando comparada à implementação sequencial, considerando um cluster com 9 nós de processamento, atingiu um speedup de 19,1.

Oct 1, 2019

By Kleidon Rodrigues de Almeida

O presente projeto descreve um trabalho de otimização dos ensaios laboratoriais de liberação do produto para fins elétricos na CSN (Companhia Siderúrgica Nacional), sendo tema de um projeto Lean Six Sigma. O foco do projeto foi otimizar os ensaios de epstein, tração e dureza, reduzindo o Lead Time de liberação dos produtos para fins elétricos e a quantidade de ensaios realizados. Para a realização deste trabalho, fez-se o uso de ferramentas e métodos Lean Six Sigma, permitindo a busca dos resultados de maneira sistêmica, superando as metas estabelecidas, gerando uma maior competitividade à empresa no mercado. Obteve-se com este projeto uma forte redução do Lead Time e da quantidade dos ensaios laboratoriais dentro de um prazo estabelecido, permitindo uma liberação para faturamento no mesmo dia de produção em 80% da produção deste produto.

Aug 7, 2018

This publication contains eight papers presented at a Bureau of Mines Technology Transfer Symposium in Charleston, W, on June 22, 1983, Five of the papers describe the results of Bureau-sponsored research on cabs and canopies for low-coal underground mining equipment. The other papers describe the efforts of three underground coal mining equipment manufacturers (FMC, Joy, and Lee-Norse) in the area of cab and canopy design.

Jan 1, 1985

By Robert M. Becker

This report (part 3 of a five-part series) presents computer programs for evaluating moments and moment relationships of the generalized probability distributions extended or developed in parts I and 2. The principal program is for evaluating the first three moments and moment relationships of the compound-multinomial distribution for finite as well as for infinite populations. This is the generalized distribution for sampling to some amount of items per sample. Another program is for evaluating the first four moments, the moments of the mean, and the moment relationships of the multinomial and generalized hypergeometric distributions. This is a general moment program in sampling to some number of items per sample or for sampling to some number of samples. This program will accept either ungrouped data, frequency data, or probability data.

Jan 1, 1965

By C. B. Manula

This report is volume 7 of an eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment. The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design. Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation," and ventilation. This volume of the final report describes the Rail Haulage subsystem of the Master Design Simulator. This subsystem can be used as a free standing model or can be linked to the Production subsystem to provide rail haulage capability. Complex rail haulage systems can be realistically simulated with this model. This report includes complete instructions for operating the subsystem as well as a program listing. In addition, a case study is included which illustrates the application of the subsystem when linked to the production subsystem.

Jan 1, 1974

By D. C. Seidel

This report describes generic procedures and equipment arrangements for conducting laboratory-scale hydrometallurgical and related waste-management experiments. It provides a starting point for personnel who have received or are receiving professional training, but do not have specific experience in laboratory procedures. With guidance, it also has application as a resource for technician training. The publication contains chapters on laboratory safety, feed-sample preparation, leaching, solids-liquid separation, and recovery from solution.

Jan 1, 1995

By L. G. Closs

Gold continued to be the primary focus of minerals exploration worldwide during 1995. Other targets, though, included primary diamonds and base metals, especially copper deposits amenable to solvent-extraction/electrowinning (SX/EW) processing. The discovery of nickel, copper and cobalt at Voisey Bay in Labrador, Canada was an unusual surprise. Meanwhile, exploration geochemistry continues to evolve to meet new challenges. The major event in this category during 1995 was the17th International Geochemical Exploration Symposium (IGES) held in Townsville, Queensland, Australia in May. The meeting was sponsored by the Association of Exploration Geochemists, which celebrated its 25thanniversary of service to the mineral industry, and the Economic Geology Research Unit of James Cook University, Townsville.

Jan 1, 1996

By Tom Retka

This three volume final report summarizes the activities and conclusions of this contract. The objective of the contract was to develop noise control modifications on a retrofit basis, for auger miner coal-cutting systems. Manuals were prepared to assist mine shop personnel in retrofitting the auger miner with these noise controls. Final Report Volume I - Details all vibration and acoustical tests conducted in develop¬ment of the noise controls. Final Report Volume II - Noise Control Modification Manual for the Jeffrey 100-L Auger Miner describes the various noise control modifications to the auger miner, along with fabrication procedures, cost and vendor information. Final Report Volume III - Noise Control Modification Manual for the Jeffrey 94-L Bridge Conveyor describes the various noise control modifications to the bridge conveyor, along with fabrication procedures, cost and vendor information.

Jan 1, 1978

The objective of this research was to evaluate the technical and economic constraints on the extraction and utilization of anthracite coal and to determine the research and development needed in order to make anthracite coal more fully utilized as a premium energy resource. In the report the contractor examines in detail the anthracite industry both past and present and evaluates market possibilities. Anthracite reserves and resources are analyzed and tabulated, and the problem of pumping and drainage from the flooded anthracite fields is covered. Current technology is considered in detail with a discussion of production techniques with potential for improvement. The contractor concludes the report with a summary of constraints on the anthracite industry and the contractor's recommendations for effecting a revitalization of that industry. An estimated production of 17 million tons annually by 1990 can be anticipated if adequate planning, research, and development to overcome present constraints are initiated in the near future.

Jan 1, 1975

By C. Michael Morgano

Static tests are costly and time consuming, so they are not always the best answer [ ]

Jan 1, 2005

By Geraldo Timotheo da Rocha

Nos últimos anos ocorreu uma deterioração considerável na qualidade química e granulométrica dos minérios de ferro utilizados na sinterização. Como resultado ficou limitada a utilização de silicatos de MgO na mistura, devido à elevação excessiva do teor de sílica no sínter, e as siderúrgicas voltaram a utilizar a dolomita como fonte de MgO. A utilização de pellet feed na mistura a sinterizar (natural ou moído) tem se apresentado como uma alternativa à elevação do teor de sílica na sinterização e a eventual redução na produtividade, compensada pela otimização das condições de misturamento. Testes em escala piloto indicam que a eventual redução na produtividade, decorrente da utilização do pellet feed, pode ser compensada pela utilização de olivina na mistura a sinterizar, em substituição à dolomita, com uma otimização do processo e da qualidade do sínter.

Aug 1, 2018

By E. P. Youngman

This paper presents one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative, to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the mining laws of British Guiana has been prepared from the best available sources in Washington and is, released subject to amplification and correction, if necessary, by United States foreign-service officials. INTRODUCTION The sources of information available in the preparation of this paper are the following: 1. The Crown lands ordinance, No. 32 of 1903, September 26, 1903.

Jan 1, 1934