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By B. W. Cavender

"World-class manufacturing" (WCM) techniques can be applied in milling operations to substantially improve productivity and reduce costs. Through the use of "just-in-time" and "total quality control" practices, WCM methods establish an environment for continual and rapid improvement in all aspects of production operations, with particular gains in product quality, costs, flexibility, employee involvement, and responsiveness to customers. This paper examines WCM techniques that can be utilized specifically in the mill, and their influence on plant configuration, organization, and scheduling practices; equipment selection and maintenance methods; training; the role of supporting staff; and methods of data collection and analysis.

Jan 1, 1993

By Robert C. Merritt

This report describes laboratory as well as pilot heap leaching investigations of low-grade sandstone ores from Wyoming, New Mexico, and Colorado. Sodium carbonate-bicarbonate solutions containing sodium hypochlorite extracted up to 86, 54, and 16 percent U308 from Wyoming, New Mexico, and Colorado ores, respectively. Ammonium carbonate-bicarbonate solutions containing sodium hypochlorite were less effective at leaching these ores. Acid leach in replicate pilot plant testing resulted in U308 extractions of 96, 88, and 81 percent from the Wyoming, New Mexico, and Colorado ores. The development of cost-effective processes for extracting uranium from low-grade ore is essential to the assurance of a continuing domestic supply of uranium.

Jan 1, 1977

By Theodore L. Turner

This Bureau of Mines report describes calcination of kaolinitic clay in a direct-fired 2-1/2- by 24-ft rotary kiln at 750° and 775° C. Methods for preparing kaolin feed materials and characterization of calcined products are discussed. Approximately 99 pct of the alumina in a typical eastern Georgia kaolin was soluble in HC1 after calcination at either 750° or 775° C.

Jan 1, 1982

By Everton Azola de Mattos

Na operação da Anglo American localizada em Barro Alto, utiliza-se 2 (dois) Fornos Rotativos no processo de fabricação de ferroníquel. Esses fornos possuem 6,2m de diâmetro e 185m de comprimento, no qual é necessário o monitoramento de temperatura (20) e vazão (4) ao longo do forno. Originalmente essas medições eram realizadas através de 2 PLC’s embarcados nos fornos, no qual recebiam as medições via cabos em bandejamentos. Esses PLC’s se comunicavam via rádio modem com os PLC’s principais dos Fornos. Durante a operação encontramos diversas dificuldades de manutenção e confiabilidade, já que os fornos operam em regime de 24h por dia e 7 dias por semana. Por várias vezes alguns cabos se danificavam devida a alta temperatura dos fornos, as bandejas que se desprendiam, falhas de cartões dos PLC’s, etc. Com isso as medições eram interrompidas. Para solucionar esse problema, foi desenvolvido um sistema de Instrumentação Wireless. Esse sistema basicamente é a instalação de instrumentos com a tecnologia WirelessHart no qual os instrumentos não possuem alimentação por cabos e sim por baterias e a comunicação é feita via sinal wireless. Esses instrumentos apresentam alta confiabilidade nas medições no qual foi possível retirar toda a infraestrutura antiga e garantir continuidade/confiabilidade nas medições.

Oct 30, 2017

By Edward G. Cunney

[Track in underground bituminous coal mines was investigated and technology has taken from other industries in order to Main information on conditions that impair the safety and efficiency of the track and to develop guidelines ad useful information on the constriction, inspec¬tion and maintenance of mine track. Volume l contains information oil the investigations, observed track conditions, useful technology from railroads and other industries, derivations of track condition descriptors and limits, conclusions, and recommendations. Volume 2, Guidelines, contains recommended standards and practices for mine track. It includes the relation of track conditions to safe speeds; descriptions and limits for measurable track features such as gage, descriptions of conditions for track components that are normally not measurable, such as subbase soils; construction requirements and techniques; inspection requirements and methods; and methods for managing and performing track maintenance work. As a research product, it 0005 nut repeat the summary or derivations. Volume 5, Inspection Handbook, summarizes recommended standards and procedures from Volume 2 and provides related information for read: refer¬ence by inspectors in tin mines. As a research product to be used in mines, it does not repeat the summary, derivations or references.]

Jan 1, 1977

By G. L. Oldright

The data presented in this paper were collected at the smelter of the Consolidated Mining & Smelting Co. of Canada, Ltd., Trail (Tadanac), British Columbia. Many thanks are due to S. G. Blaylock, vice president and general manager, James Buchanan, smelter superintendent, and George Murray, assistant smelter superintendent, for their broad general policy in permitting these data to be taken and published. life are also grateful for the help given by the staff members stated in Paper XI, Report of Investigations Acknowledgment is given several excerpts from experiments by F. E. Lee, head of the research staff. INTRODUCTION The past reputation of zinc as an ingredient in lead blast furnace slags has been bad. Zinc is thought of as a cause of accretions in the shaft of the blast furnace, of hot tops, of the formation of "zinc mush" in the crucible and forehearth, of lead-rich slags, of viscous slags, and. of low capacity in smelting.

Jan 1, 1934

By B. J. Moore

This Bureau of Mines publication estimates that U.S. helium resources as of January 1977 were 710 billion cubic feet. These resources are broken down into four classifications, as follows: Helium in measured natural gas resources and in storage, 201 billion cubic feet; helium in indicated natural gas resources, 150 billion cubic feet; helium in hypothetical natural gas resources, 175 billion cubic feet; and helium in speculative natural gas resources, 184 billion cubic feet.2 Most of the helium in natural gas is presently dissipated as natural gas is consumed as fuel and for other purposes. Helium resources of the United States may also be divided into three other categories: (1) Depleting and undiscovered natural gas resources, 589 billion cubic feet; (2) nondepleting natural gas, 83 billion cubic feet; and (3) storage, 38 billion cubic feet, of which 37 billion cubic feet is federally owned and 1 billion cubic feet is privately owned. The United States does not have any significant leasehold rights in the depleting fuel gas resources. However, through the Department of the Interior, it does have leasehold rights to about 70 percent of the helium found in nondepleting natural gas, and it owns over 90 percent of the helium in storage.

Jan 1, 1979

To the Members It has been, and is the endeavor of the A. I. M. E. to serve each and every member. One of the means of letting the membership know what is going on in the mining; metallurgical and chemical fields, and by far the most important, has been our monthly Bulletin. To publish this costs money, and to partly defray the costs, it was decided to accept such advertising as could be secured. The A. I. M. E. is the only one of the American National engineering societies whose dues are as low as $10 per year, and it actually spends more upon the Bulletin and Transactions than the sun total it receives for clues. Hence the need of advertising revenues. We are planning even greater improvements for your Bulletin-improvements that will help you in your work. It will mean a better publication, with more information than ever before. To successfully carry out our plans, we must have your co-operation. We are not asking you for financial, but for your moral support. With that we shall accomplish a great deal. What we ask of you, brother member, is to give evidence to those patronizing our advertising pages, that you not only read the editorial pages, but the advertising section as well, and that you have in mind the welfare of your Institute by consulting the advertising pages when in the market for equipment. Do you realize that if you mention your Bulletin when writing advertisers or purchasing supplies, that not only would your publication secure more advertising, but better satisfy present advertisers. We have reason to know that our advertisers secure business as a result of our publication, but they demand some evidence that you see their advertisement. Unfortunately, our members do not as a rule mention where they saw the advertisement, and as a consequence advertisers have no means of knowing whether their investment in the Bulletin is paying. The A. I. M. E. Bulletin can be made the best advertising medium in the mining, metallurgical and chemical fields, simply by each member doing his bit. It is very little to ask of you, and the returns to the mining industry will be enormous.

Jan 9, 1915

By Wagner Duarte Flores

A demanda por tubos de aço com rigorosos requisitos de propriedades mecânicas tem crescido devido à exploração de reservas de petróleo e gás natural em regiões remotas e em ambientes hostis. Um grande desafio para as siderúrgicas é prever as alterações de propriedades mecânicas que ocorrem durante a conformação chapa/tubo, associadas ao encruamento e ao efeito Bauschinger, visando atender às especificações no tubo. Nesse estudo, foi avaliado o efeito da conformação chapa/tubo nas propriedades mecânicas do aço API X60 (TMCP). Para tal, foram realizados ensaios de tração, de impacto Charpy e de CTOD, em amostras de chapa e de tubo, e análise metalográfica, além de simulação do efeito Bauschinger por meio de ensaio cíclico compressão-tração. Os resultados dos ensaios de tração, tanto com os corpos de prova plate type quanto com round bar, apresentaram aumento da tensão limite de escoamento e redução da ductilidade, devido ao encruamento. Nos corpos de prova que sofreram aplainamento, esse aumento foi menos pronunciado, justificado pela ocorrência do efeito Bauschinger. A simulação do efeito Bauschinger confirmou a indicação de queda do limite de escoamento devido ao ciclo reverso de deformação. A tenacidade não foi fortemente afetada após a conformação do tubo.

Aug 16, 2017

By Solange Tamara da Fonseca

Uma das maneiras de se reduzir os custos no transporte de cargas é aumentando a quantidade de carga transportada por vagão, isto eleva a tensão no eixo do vagão e, consequentemente, a roda deve possuir maior dureza sem perda da tenacidade para suportar o desgaste. Para atingir os níveis de dureza necessários estão sendo desenvolvidas rodas ferroviárias com aços microligados ao nióbio (Nb), vanádio (V), molibdênio (Mo) e titânio. A empresa MWL Brasil fabricante de rodas ferroviárias forjadas desenvolveu dois aços microligados: 1° contendo o elemento microligante vanádio (0,13 % em peso) e 2° contendo os microligantes nióbio+molibdênio (0,014 % + 0,12 %, respectivamente), ambos os aços com 0,7 % C. Estes aços foram analisados microestruturalmente e mecanicamente a partir da roda ferroviária pronta. A microestrutura destes aços é composta basicamente por ferrita-perlita. Nas propriedades mecânicas o aço ao V apresentou os melhores resultados em todos os ensaios (tração na temperatura ambiente e 540 ºC, energia absorvida no ensaio Charpy e KIC) quando comparado ao aço sem microligantes ou com a adição de Nb+Mo. O melhor desempenho do aço ao V foi atribuído ao seu menor tamanho de grão austenítico e espaçamento interlamelar da perlita mais refinado.

Aug 16, 2017

By L. J. Kane

While analyzing synthesis gas produced from coal, the Bureau of Mines found that conventional procedures for naphthalene determination were difficult and time consuming. The Bureau developed a rapid and sensitive turbidimetric procedure, which requires only simple instruments and hence can be used in plant-control laboratories. The gas is passed through a saturated aqueous solution of picric acid at 3° to 4° C. whose turbidity is then measured at room temperature. A dispersing agent is added to prevent coagulation of the suspension on warming. Only about 1 mg. (0.015 grain) of naphthalene need be absorbed, and precision and sensitivity are a few ten-thousandths of a grain, or a few hundredths of a grain per 100 cubic feet. The determination can be completed less than 10 minutes after absorption. INTRODUCTION One of the functions of the Branch of Coal Gasification, Bureau of Mines, Morgantown, W. Va., is to develop economical methods for manufacturing, from coal, a mixture of hydrogen and carbon monoxide for producing hydrogen, methane, and other gaseous fuels. This raw gas may contain many impurities, including naphthalene. This impurity is usually determined by first forming naphthalene picrate in a water solution of picric acid, separating the picrate, and titrating the unreacted picric acid or the picrate itself.

Jan 1, 1957

By Richard L. Fowler

An automatic steering control system was designed, installed and tested on a coal mine shuttle car. The system utilizes sensors and associated signal processing electronics developed under a previous phase of this contract. The automatic steering system performs the routine guidance functions of turning corners and straight-through tramming. The shuttle car driver retains full authority of speed, braking, load and unload functions and at any time may exercise his option with manual override or steering. Steering information is generated from signals derived from the existing Lateral Guidance sensor subsystem, and all operational features of the previously developed open-loop system are retained. Above ground system tests were conducted in a simulated mine constructed of wood panel ribs. Results were in good agreement with prior hybrid computer simulations undertaken to validate the basic control system over a broad range of conditions and to select system parameter values. The automatic steering system was successfully demonstrated in the above ground simulated mine to USBM technical representatives. Designed to meet USBM permissibility requirements, the system is ready for a Phase II underground testing program. Testing in actual underground mine environment is expected to provide additional data regarding recommended performance improvements and implementation techniques.

Jan 1, 1975

By Marcelo Ferreira Martins, Breno Totti Maia, Sandro Luís Zahner, Leandro Martins Perreira, Paulo Roberto Ogliari Hopperdizel, Geraldo Vieira da Silva

O reator EOF foi desenvolvido no Brasil nos anos 80 com características únicas. O pré-aquecedor de sucata e a distribuição dos pontos de injeção de gases oxidantes e combustíveis conferem estas características. Um reator dinâmico e versátil capaz de adequar-se a grandes variações de carregamento de gusa e sucata, porém com equipamentos de injeção calcados ainda nos princípios da concepção da tecnologia. O objetivo deste trabalho é apresentar a etapa 1 de uma seqüência planejada de 3 etapas os desenvolvimentos que visam o aumento de produtividade do EOF. Nessa etapa 1 são apresentadas os ganhos relativos a modificação do número de pontos de injeção de oxigênio e a adequação desses pontos para condição supersônica de sopro.

Oct 1, 2019

By Raphael Henrique Morais Reis

Esse artigo apresenta o desenvolvimento de um protótipo computacional para aplicação em estudos de sistemas termodinâmicos metalúrgicos, através de um sistema web, agilizando consultas as propriedades de substâncias e compostos contidos em Carvalho (1977). O projeto teve início analisando três fatores, primeiro, a importância dos softwares termodinâmicos computacionais na otimização da produção industrial, segundo, a falta de um software termodinâmico com desenvolvimento nacional, e terceiro, a restrição ao acesso a software termodinâmicos proprietários, com licenças pagas. Seu desenvolvimento seguiu a estrutura apresentada por Neto (2012), constituindo, banco de dados, software e aplicações, respectivamente. O sistema web supriu as dificuldade de instalação e interação, podendo ser acessado por quaisquer dispositivos (computadores, tablets e smartphone) conectados a internet.

Oct 30, 2017

By Moyle F. J

This paper describes an apparatus which was developed to study solid-vapour equilibria and presents results which were obtained during a study of the FeCI3-AlCI3-CI2 system. Analysis of the results showsthat fractional desublimation might offer a means of achieving a useful separation of the iron and aluminium chlorides produced by the chlorination of bauxite. The results, presented in the form of isothermal vapour pressure curves covering the range of temperature 160-200°C, support the earlier findings of Semenenko et al (Dokl Akad Nauk SSSR, 154: 42-43 (1964)) that the solid phase contains two terminal solid solutions.The equilibrium constant for the formation of the mixed dimer, FeAICI6, was approximately 4. The latent heat of sublimation of aluminium chloride varied from 18 to 26 kcal/mole AI2CI6 for solid compositionsfrom 0.9 to 0·5 mole fraction FeCls3.

Jan 1, 1979

By W. E. Roscoe, H. Agnerian

The contour method can be used to estimate the mineral resources of a mineralized body. It relies on geological interpretation and allows the geologist to determine the plunge of a mineralized ore shoot along the dipping plane of the mineralized body. The technique is best applied to estimate tonnage and average grade of relatively planar bodies, i.e., where the two dimensions of the mineralized body are much greater than the third dimension, such as Archean lode gold vein deposits or mantos of massive sulphide mineralization, based on exploration drilling. For these types of deposits, the contour method can provide a clear view of the “mineralization landscape” with “peaks” and “valleys” along the plane of the mineralized vein. The technique also reduces the “nugget effect” of local high values commonly present in gold deposits. With sufficient drill hole information, the contour method may be used to estimate the tonnage and average grade of individual blocks within a mineral deposit. General procedures for the contour method are described in this paper, along with examples and explanatory notes.

Jan 1, 2002

By Ewan Wingate, Ranjit Prasad, Yanjun Liu

The use of phosphorus by mankind is long established. From use in agriculture, foods, high tech electronics, and more recently in EV battery cathode production, one cannot escape its impact on today’s society. This paper will review and describe the circular journey of phosphorus through its value chain from the mining operation of phosphate ore through beneficiation into downstream chemicals production and finally into the EV battery cathode production space. This will include a review of phosphoric acid production from phosphate concentrate using wet process route and thermal route. The wet process route discussed will be via dissolution of phosphate concentrate by sulphuric acid. The thermal route will discuss thermal decomposition of phosphate concentrate using submerged arc furnace to produce yellow phosphorus followed by its combustion to produce phosphorus pentoxide and subsequent hydration to produce phosphoric acid. It will also discuss briefly other phosphate derivatives for specialty chemicals and recovery of phosphorus units from wastewater treatment plants, sewage sludge and incinerator ash. Finally, the paper will discuss the use of phosphorus in EV batteries in the form LFP cathode materials and its production. It will also briefly discuss the LFP battery recycle.

Sep 11, 2023

By Mark P. Meyer

A mineral investigation of the Chugach National Forest, Alaska was conducted jointly by the U.S. Geological Survey and the U.S. Bureau of Mines from 1979 to 1983 as part of the RARE II program. The U. S. Geological Survey remapped the geology and distribution of mineral resources. The Bureau investigated mines, prospects, and mineral occurrences. Previously unreported mineralization in three areas, Long Bay, Wells Bay, and Miners River were discovered in the western portion of the SOUND study area. Copper, lead, zinc, gold, silver, nickel, cobalt, fluorite, and arsenic were found in north-northeast to north-northwest trending shear zones, veins, felsic dikes, and granitic intrusives in Tertiary Orca Group metasedimentary rocks.

Jan 1, 2011

By J. M. Gomes

Bench-scale flotation tests were conducted on two western tactite ores to study the recovery of tungsten and zinc minerals. The investigation, which is part of the Bureau of Mines ongoing program to develop methods for beneficiating minerals and metals from domestic low-grade ores, demonstrated the feasibility of producing scheelite, sphalerite, and their bulk concentrates. Sphalerite concentrates containing 51 to 53 pet Zn and less than 0.11 pct W03 were selectively recovered prior to scheelite flotation. Zinc recovery ranged from 85 to 91 pct. Scheelite concentrates containing 17 to 25 pct W03 were then recovered from the ore; tungsten recoveries ranged from 88 to 94 pct. Bulk flotation concentrates containing 84 to 91 pct of the W03 and 87 to 95 pct of the zinc also were prepared. More than 98 pct of the W03 in a bulk concentrate containing 9 pct W03 was extracted by autoclave leaching with a soda solution. The zinc remained in the leached residue.

Jan 1, 1982

During the period 1979 thru 1982, Multi Mineral Corporation conducted a mining research program at the United States Department of the Interior's Bureau of Mines Oil Shale Mining Environmental Research Facility in the Central Piceance Creek Basin, Rio Blanco County, Colorado. The program consisted of mining, environmental and geotechnical research data and the results are described in this report.

Jan 1, 1983