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By J. W. Buch

IN THE FIELD of track haulage, interest has seemed to center on the question of larger mine cars both for handling material from loading point to shaft bottom or surface, and for shuttle service. Saving of time in car changing is obvious if larger cars are used. In addition, shorter trips result where car transportation is from face to opening without transfer. This also brings about side-track and equipment savings. Track shuttle service, using large automatic-dump cars (10 tons) between loading machines and trip loading point, has been a satisfactory solution for the operator who mechanizes a working mine regularly equipped with a large number of small mine cars. This development in track shuttle haulage, has made track installation and maintenance increasingly important, requiring closer supervision.

Jan 1, 1942

By Scott G. Britton

In this chapter, I shall discuss railroad con¬struction for modern underground coal mines. Because men, materials, and supplies are being moved more often and farther by rail, the ef¬ficient and safe construction of the system takes on new importance. Most large coal mines are opting to use track haulage over other support transportation systems because of cost, ease of installation, reliability, and other factors. En¬gineers tackling the problem of designing such a transportation network must be aware of all the steps required for an effective transportation system design. This chapter discusses all aspects of efficient trackwork construction. The areas covered in¬clude design factors, laying the track, installing turnouts and switches, and installing trolley wire. Each area includes a description of the steps needed to complete the work.

Jan 1, 1983

By John W. Buch

IN my review a year ago I pointed out that a small coal-mining companies as well as large had decided that the so called ?central shop? was a benefit. These central shops replaced in a large measure the commercial shops operated by those who have no direct connection with production of cod. Central shops in this time of salvage and major repairs have proved their worth. In addition, many of the larger companies had in their central shops equipment available for the production of many thousands of parts for our vast war machine and, as subcontractors, are doing this type of work. This is a real contribution to the war endeavor. Lack of new supplies has resulted in exhaustion of those stocks formerly stored or hidden in underground shanties. This means that the small stock of repair parts likely LO be available to any mine

Jan 1, 1943

By A. T. Yu

There are compelling reasons for us to look to our Country's Western coal. Despite its inherent low BTU content, Western coal's low sulphur content provides a near-ideal answer to satisfy our in- dependent goals of clean air and self-sufficiency in energy. Vast reserves, thick seams and amenability to low-cost strip mining serve as a powerful economic basis for its viability as a primary and dependable source of energy for the coming decades. A major consideration, the solution of which may not be quite obvious, is transportation cost. These abundant deposits are remote from the utilities of the heavily populated eastern regions of the United States (Figure 1). A Western coal mine in Montana is likely 1500 miles or more from an eastern power plant. The comparable distance to an eastern coal mine may be only 200 miles. Thus, the question is: How can the haulage cost of our Western coal be substantially reduced to an acceptable level? If resolved, western reserves of coal will be one of the key solutions to satisfying our Nation's energy needs.

Jan 1, 1975

H. D. HIBBARD, Plainfield, N. J. (written discussion *).-While this valuable and timely paper may not go to the root of the matter, it deals with many of the elements and factors involved. It might be taken as the engineer's solution of the case, starting with the assumption that steel is steel, while the tendency for a rail to have transverse fissures may, and probably does, depend, in part at least, on conditions met before it reaches the track. Admitting with the author that "brittleness of fracture in all grades of steel is characteristic of fatigue tests" we may yet look farther back to find out, if possible, why some rails and some steels are more prone to have transverse fissures than others, for it has been found that rails from certain heats of steel developed these fissures under a service which

Jan 3, 1918

By W. A. Haley

Wheel loaders became important bulk materials handling tools in the early fifties. As they grew in stature, productivity, reliability, and acceptance, the demand for larger, more rugged machines evolved. In the early sixties, the introduction of a 6-yard model by a major equipment manufacturer led quickly to widespread experimenting and rapid worldwide acceptance in loading blasted rock in stone quarries and smaller metal mines. As the wheel loaders grew in popularity for shot rock loading, larger models, 12- to 15-yard size were developed and saw widespread use by 1970. In the past 20 years, at most quarries and small to medium size mines, most cable operated power shovels have been replaced by large wheel loaders and more recently, hydraulic excavators as the primary loading tool. Wheel loaders larger than the 15-yard class are not used widely. Until about 1970, very few overburden haulage trucks were used in domestic coal mines. About that time, many states started enforcing stringent mine relcamation regulations and in 1977, even more stringent federal legislation was passed. These controls brought about drastic changes in coal surface mining methods in the mountainous areas of Appalachia, in smaller midwestern mines and in the large mines of the western states. Basically, simple material casting methods were replaced at most eastern mines by "haul-back" and "mountain top mining" methods using controlled placement of overburden as it is removed from the coal. These methods dictated much more extensive use of loaders/ shovels and trucks to the point that most coal mining in those areas is now by loader/shovel trucks methods. And those areas have become the home of the country's largest population of large wheel loaders and trucks in the 35- to 85-ton size class with a trend to even larger trucks and shovels. To maintain equal production or provide for growth, the new methods have caused a sharp increase in machine intensity to the extent that at some mines, up to three times as many machines were required to mine a million tons of coal in the late seventies as compared to the machine needs in the sixties. Mining costs and coal prices also took a big jump in the mid-seventies, paralleling the drastic price increases in oil and other forms of energy.

Jan 1, 1984

By Cristiane Lazzaro Barbosa

Visando a melhoria contínua no atendimento a seus Clientes, além de garantir a confiabilidade e rastreabilidade do processo de tratamento das manifestações de seus clientes e dos sinistros ocorridos com os produtos adquiridos, a ArcelorMittal Brasil Planos investe na atualização do sistema que suporta este processo e na convergência para o SAP. O Projeto, denominado QM Comercial, utilizou os módulos QM, DMS, SD e WF do SAP ECC para implementar a solução de registro, documentação, elaboração do parecer com a análise de várias áreas/unidades da empresa e a orquestração das atividades dos processos comerciais/financeiros de conclusão da reclamação/sinistro. Todas as etapas com rastreabilidade e controle de tempo de resposta das áreas envolvidas.

Aug 16, 2017

By Elena Kalinin Toss

Inúmeras indústrias necessitam de sistemas de tratamento de água que favoreçam o processo de descarte de seus efluentes, além do aproveitamento do reuso de água. A mineração e siderurgia podem apresentar rejeitos com metais, que necessitam de tratamentos econômicos e sustentáveis. A biossorção é um exemplo de técnica que vem ganhando interesse em diversas áreas da pesquisa. O objetivo do estudo foi avaliar a porcentagem de remoção de íons de níquel de uma solução monoelementar de cloreto de níquel II (NiCl2+) em pH 2, 4 e 6. Para isso, utilizou-se um sistema de batelada, e 1g de consórcio bacteriano liofilizado (sem ser autoclavado) isolado de amostra de terra. Os resultados indicaram que a eficiência da biossorção foi maior para o pH 6, e que o consórcio bacteriano foi eficiente na remoção de íons de Ni2+.

Oct 30, 2017

By Jayna Kátia Dionisio dos Santos

Os materiais compósitos tornaram-se ao longo dos últimos anos, essenciais ao surgimento de novas tecnologias. Para tanto, é imprescindível que alguns cuidados sejam considerados ao desenvolver estes materiais, como o uso do processo de fabricação adequado e a aderência fibra/matriz, sendo este último um fator preponderante na resistência mecânica final do produto. Também se torna cada vez mais necessário o desenvolvimento de materiais com capacidade de utilização ecologicamente correta. Diante disso, foi fabricado um compósito parcialmente ecológico, utilizando como reforço um tecido de sisal, e como matriz resina poliéster. Ainda, buscando a melhoria da aderência fibra/matriz foi efetuado um tratamento com Hidróxido de sódio (NaOH) a uma concentração de 3% no reforço de sisal. Para a caracterização mecânica do compósito, foram realizados ensaios de tração uniaxial nas fibras tratadas e não tratadas, bem como nas lâminas que utilizaram estas fibras como reforço, mediante a norma ASTM 3039. Quanto a esta propriedade mecânica, foi observado que o tratamento químico superficial diminui expressivamente a resistência à tração da fibra e, em contrapartida, aumentou a resistência do compósito polimérico quando comparado ao que utilizou fibra não tratada, confirmando assim o efeito positivo do tratamento na superfície do reforço de fibra natural.

Aug 8, 2018

By Saulo Brinco Diniz

O presente trabalho buscou explorar a influência de um tratamento térmico de ressolubilização, realizados com distintos tempos (70, 80 e 90 minutos) a uma temperatura de 510ºC, na microestrutura e na dureza de uma liga de alumínio 7475- T7351. Para verificar a influência destes tratamentos térmicos foram utilizados um durômetro (fabricante EMCOTEST, modelo Duravision 300) e um microscópio óptico (Olympus, modelo GX51). Após os resultados obtidos, pode-se evidenciar que a liga de alumínio em estudo sofre um envelhecimento natural (a temperatura ambiente), e dentre os tempos de encharque estudados, 70 minutos é o tempo que possivelmente obtém-se a maior ressolubilização dos precipitados.

Aug 17, 2017

By Ivan Kwei Liu Kam

O presente trabalho propõe a carbonetação a laser de ferro puro para a formação de uma camada endurecida na superfície. A formação de uma camada dura permite obter peças com melhores propriedades tribológicas, mas sem alterar as propriedades volumétricas do sólido. Foram realizados experimentos em quatro condições de tratamento a laser, com uso de uma fonte do tipo fibra de Yb:vidro. Análises microestruturais e de dureza mostraram a formação de camada ledeburítica e martensítica, dependendo das condições experimentais, até cerca de 50 µm de profundidade. Análises por calorimetria permitiram, também, verificar que a absortividade do laser na peça variou entre 30 e 46%. Estes resultados mostram que o uso de laser para a carbonetação de peças ferrosas, com a metodologia proposta, permite um alto rendimento, alta dureza da superfície e baixo aporte térmico ao material.

Aug 7, 2018

By Jorge Cáceres

El presente texto describe los diversos métodos para el tratamiento del agua de la Planta de Precipitación. Asimismo, se presenta el flow sheet, la maquinaria que se instaló en el área de San Felipe y se muestran los costos del tratamiento de dichas aguas al ser descargadas completamente limpias al Río San Felipe.

Nov 1, 1973

By Enrique Monge

Para resolver la crisis de combustible por la que atraviesa el Perú, se requiere reemplazar gradualmente el petróleo de consumo nacional por carbón mineral de los yacimientos del Santa, Oyón o Huayday. En ese sentido, el presente texto señala el tratamiento adecuado para la explotación del carbón a través de conocer el comportamiento de los carbones en los procesos de lavado, pulverización, briquetaje combustión, coquificación y gasificación. Para efectuar dichos estudios se recomienda la creación de un Instituto de Investigación Experimental, financiado por el Estado y por la industria -petrolera y carbonera, que opere en forma independiente, resolviendo cada uno de los numerosos problemas que afectan el tratamiento de los carbones como la liberación y separación de granos; expansión de carbón; fusibilidad de cenizas; combustibilidad y reactividad; rendimiento de gases; temperaturas de combustión; coquificación y gasificación; presión y exceso de aire para combustión; plasticidad, aglutinación y aglomeración de carbón, impermeabilidad, coherencia y resistencia de briquetas; etc

Jul 1, 1959

By F. Habashi

The peninsula that lies between the Black and Mediterranean seas, called Asia Minor by the Romans and Anatolia by the Greeks, was one of the crossroads of ancient civilizations. The fall of Constantinople in 1453 was a turning point in the history of mankind. Visits to Istanbul, Ankara, Eskisehir, Cappadocia, and Trabzon will be given together with the history of the country. Mineral resources of the country will also be briefly outlined.

Feb 23, 2014

By Julio Bustamante, Angel Ríos, David Velazco

Antamina es un complejo minero polimetálico que produce concentrados de cobre, zinc, molibdeno, plata y plomo. En Antamina, la perforación de los sondajes diamantinos es realizada por los Socios Estratégicos. Posteriormente, se realiza la descripción de la geología en el área del Core Shack, adonde llegan las cajas de testigos. La información de las leyes está compuesta por análisis de plasma de acoplamiento inductivo (ICP), espectroscopia de absorción atómica (AA) y análisis volumétrico (Volumetría). El trabajo de recopilación de información de los sondajes por parte del equipo de perforación era muy laborioso y rutinario. Para evitar demoras y errores en la visualización y análisis de la trayectoria de los sondajes, se implementó la automatización de la trayectoria de la perforación en tiempo real.

Sep 30, 2022

[RECEIPTS Magazine, Advertising $ 32,823.60 Sale of Magazines 3,933.29 Total Magazine $ 36,756.89 Dues, Arrears 5,866.97 Dues Current 100,223.80 Dues of New Members 6,143.29 Dues in advance 1,586.32 Initiation fees 6,820.00 Sale of Transactions 5,464.99 Sale of Binding 5,618.90 Sale of Pyrometry Volume 336.30 Sale of Indexes and Emmons 106.10 Sale of Pamphlets 575.32 Miscellaneous Receipts 105.60 Interest on Bank Balances 1,217.67 Interest on Life Membership Investment 512.18 Interest on James Douglas Library Fund 5,678.67 Total Receipts $177,013.00] [ ]

Jan 1, 1925

RECEIPTS [Magazine Advertising $ 62,564.83 Magazine Sales 3,591.44 Totalm 66,156.27 Dues, Arrears7,032.88 Dues. Current96,839.74 Dues, New Members6,525.00 Dues, in advance 1,907.02 Initiation Fees7,584.00. Sale of Transactions3,909.03 Sale of Binding7,845.05 Sale of Special Editions 338.20 Sale of Year Book76.20 Sale of Pamphlets1,189.06 Sale of Authors' Reprints867.54 Miscellaneous Receipts62.93 Interest on Bank Balances1,712.89 Interest on General Reserve Fund337.50 Interest on Life Membership Fund557.84 Interest on James Douglas Library Fund....5,491.89 Total Receipts$208,433.04] [ ]

Jan 1, 1925

By John J. Mazza

Treatability studies were performed to determine the effectiveness of two commercially available treatment methods (solvent extraction and thermal desorption) for the removal of PCBs and PAHs from contaminated dredged riverbed sediments. The solvent extraction method evaluated was the B.E.S.T. process which extracts the contaminants with triethylamine. The thermal desorption method utilized was the ATP process which desorbs the contaminants at elevated temperature in an anaerobic atmosphere. A description of both methods and. an evaluation of the treatability study results is provided. Each treatment method was used to treat two separate samples (high and low concentration) from the site. Overall, both methods proved to be very effective with solvent extraction achieving 98% removal of both PCBs and PAHs and thermal desorption achieving better than 99% removal of both the PCBs and PAHs from the high concentration sample. Both solvent extraction and thermal desorption achieved greater than 99% removals of PCBs and PAHs from the low concentration sample. Vendor cost estimates for full scale treatment were roughly equivalent. The primary differences between the two methods lies in the realm of permitting, operational requirements, and emission concerns.

Jan 1, 1994

By James S. Graham

Specifications for treated round wood piling are presented for the engineers consideration. Included in the text are background information, technical committees, Chellis, quality, treatment, static and dynamic stresses, accessories, and existing codes and standards. The specifications are also available using Word Perfect on 3.5 or 5.25 inch size disks provided by the National Timber Piling Council. Note: DFI recommended wording is wood, head, and toe, instead of timber, butt, and tip.

Jan 1, 1992

By Ali Sogue, Steven Schurman, R. Jensen

This paper presents the results of the remediation of the Gregory Gulch #1 Superfund site, an EPA Clear Creek Superfund project located in central Colorado. The Gregory Gulch #1 site was an historic gold mine and mill located within the city limits of Central City, Colorado. Remediation efforts included the use of the Envirobond™ additive to chemically bind the metals in 3,000 tons of acid generating mine waste that contained high levels of arsenic, lead, zinc and mercury. The toxicity of the mine waste amended with Envirobond™ was not only reduced to RCRA TCLP standards but also to the more stringent UTS standards. The final cost of the treatment was much less than standard industry solidification processes and significantly less than offsite disposal options.

Jan 1, 1999