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By J. B. Gayle

In a modern blast furnace, production depends, to a large extent, on the rate at which the furnace gases can be forced through the charge. Since these gases must make their way through the voids between particles of coke, ore, and limestone, the size and size distribution of the stock-column materials are of considerable importance. Also, because the coke pieces support the weight of the overburden and provide the majority of the voids through which the gases pass, their ability to withstand the shattering and abrading forces to which they are subjected should be related to the maximum obtainable production for any particular furnace. Although the wide acceptance of this point of view is indicated by the ever-increasing demand for stronger and more uniform blast-furnace cokes, economic considerations demand that a quantitative evaluation of the relation between coke quality and blast-furnace performance be made available to the industry at the earliest possible date. The following studies of size-distribution patterns and breakage processes were, therefore, conducted as a part of a preliminary investigation intended as a basis for future studies of the relation between coke quality and blast-furnace performance. The major findings may be summarized as follows: 1. New evidence for the presence of two independent distributions of sizes in run-of-oven cokes has been obtained, and a method for characterizing and estimating the relative importance of the individual distributions has been demonstrated. This method has also been used to study the different types of degradation taking place during the tumbler test.

Jan 1, 1954

"La mina Rublo disminuyó sus costos de explotación mediante la aplicación de pastillas de carburo ""continental"" en la preparación de barrenos en el lugar mismo de la mina. Por tal motivo, el presente texto señala los datos obtenidos con la preparación de barrenos y la economía obtenida con este sistema. La preparación de barrenos consiste en un corte de la cabeza del barreno a través del un previo calentamiento, para luego ser derivado en una nueva cabeza, de manera que la superficie plana tenga una conexión del conducto de agua y que la forma requerida para la cabeza de este barreno sea en forma de Chaflán, a través de la barra de soldadura. Una vez conectado el conducto de agua, se cortan los rebarbados del barreno en los extremos del canal para la pastilla, obteniendo el ángulo exacto del barreno para la perforación. Finalmente, el canal para la pastilla es limado y cubierto con soldadura, colocando la pastilla en la soldadura y revistiéndola nuevamente para ser fijada en el barreno. De otro lado, los factores económicos -en tanto mano de obra y el costo de materiales-, no representan mayor costo en los barrenos, obteniéndose un precio menor de US$ 2. 60, a diferencia de los barrenos anteriores. Así, la reconstrucción de los barrenos resulta fácil y barata a través del uso de pastillas de carburo de tungsteno ""Continental"", evitando problemas de roturas o de soldadura. "

Jul 20, 1959

By Rayleen Riske

Why do we look for better reconciliation when times get tough? Why wait? Mine reconciliation should be a priority throughout the good times too. In fact, with good reconciliation, those good times are going to be even better and will help pave the way to success through those preventable bad times. Reconciliation throughout the entire mining value chain requires the capture, validation, and analysis of copious amounts of data. This task can be daunting for a team in a small mine, let alone reconciling across a suite of large mines. This paper will outline the different ways we can reconcile across the value chain, why we should reconcile over differing periods of time and how Snowden?s solution to proving reconciliation can be a simpler, reliable and transparent process. Snowden?s Reconcilor is proving to be a valuable tool on any mining scale, by capturing, validating, sorting and reporting data for timely decision making by the site geologist through to corporate management. By instigating vigorous reconciliation, you are setting your mine up for the future. Not only will you have the means to analyse your current processes and measures, but you will have the opportunity to identify and improve your mine?s performance from the resource model through to the final product.

May 1, 2010

By Celedonio Aranda

El presente texto busca optimizar el entendimiento del comportamiento geoquímico en condiciones neutras de Ph e hidrológico de los cinco principales tipos de roca de desmonte (caliza, hornfels, mármol, intrusivo y skarn) que hay en la mina Antamina, cuyo yacimiento es de tipo skarn polimetálico inmerso en una extensa zona de caliza. Para tal estudio, se realizaron experimentos a diferentes escalas tanto a nivel laboratorio como en el campo y y las pruebas cinéticas de campo están dadas por la instalación y funcionamiento de celdas geoquímicas de campo y de pilas experimentales.

Sep 12, 2011

By Jairo Romero, Fernando Pajuelo

La voladura de rocas marca el inicio del proceso de conminución, seguido por etapas secuenciales de chancado y molienda para reducir el tamaño. La energía total necesaria en la conminución depende del tamaño de las partículas y de la resistencia del material a la fragmentación. En este artículo, nos enfocamos en un aspecto relacionado: la influencia de la distribución de carga en la energía específica requerida para el chancado y la molienda. Se llevaron a cabo voladuras de rocas con minerales polimetálicos utilizando diferentes valores de FP y distribuciones de carga diferentes.

Sep 29, 2023

By D. Komljenovic, V. Kecojevic

Selection of the best possible truck type (model) is of crucial importance for the mine decision-makers. In this paper, authors contribute to the body of knowledge by developing a novel methodology for the selection of mining truck. Both the Coefficient of Technical Level (CTL) and Analytic Hierarchy Process (AHP) methods were used in this study. The CTL represents a mathematical function which takes into consideration the interrelations among the main technical parameters of mining trucks. The authors developed a hierarchical structure where both attribute categories and their importance, i.e. priority or weight in the selection process were determined. For each category, a number of sub-attributes and their priorities were assigned, and a pairwise comparison among them was performed using the AHP method. In the final part of the study, the CTL was integrated into the AHP and represents a holistic approach in the selection of mining trucks. A case study on 180 tonnes truck category offered by five manufacturers was carried out. A sensitivity study of obtained results was also performed indicating a very stable solution. The methodology presented in this paper may be used by mining operators to help in the selection of a specific type when acquiring a new truck. It may also be used by equipment manufacturers to help in analysis of potential benefits of envisaged modifications concerning an existing truck type and/or development of a new type.

Jan 1, 2007

By Harold M. Smith

Important discoveries of new oil fields were made in 1937 in the State of Illinois. Oil production, which was virtually constant during 1934, 1935, and 1936 at about 4,400,000 barrels a year, a increased to 7,499,000, barrels during 1937, and in 1938 this production was trebled. In 1939, 94,302,0003/ barrels were produced (almost four times the 1938 quantity), making Illinois one of the cost important oil-producing areas in the United States. The Bureau of Mines has analyzed 35 samples of petroleum from these new Illinois fields and presents the analyses herein. Included with them in this report are analyses of seven samples from fields developed before 1936.

Jan 1, 1940

By Harold M. Smith

[Important discoveries of new oil fields were made in 1937 in the State of Illinois. Oil production, which was virtually constant during 1934, 1935, and 1936 at about 4,400,000 barrels a year, a increased to 7,499,000, barrels during 1937, and in 1938 this production was trebled. In 1939, 94,302,0003/ barrels were produced (almost foot times the 1938 quantity), making Illinois one of the cost important oil-producing areas in the United States. The Bureau of Mines has analyzed 35 samples of petroleum from these new Illinois fields and presents the analyses herein. Included with them in this report are analyses of seven samples from fields developed before 1936.]

Jan 1, 1940

By John C. Cook

This was a study to identify and evaluate known technologies employing electromagnetic resonance phenomena in solid minerals for their identification and assaying, particularly assay logging of exploratory boreholes. A comprehensive literature search and study revealed some little known NMR (nuclear magnetic resonance) techniques developed by Professor G. J. Béné's group at the University of Geneva, Switzerland. These are suitable for use in weak, inhomogeneous magnetic fields. Laboratory NMR tests of numerous U.S. ore minerals showed good identifying signals from phosphates, fluorspar, bauxite, oil shale, and spodumene (lithium) ores, but not from the copper, lead, antimony or manganese ores tested. Use of EPR "signatures" for such ores is suggested. A conceptual design for an NMR assay logging system is proposed.

Jan 1, 1978

By N Cusworth

The development of a resource project inevitably requires the investigation of a vast range of issues across most engineering disciplines û mining, metallurgical, chemical, civil, electrical, mechanical and environmental û as well as the geosciences. It is also a characteristic feature of the resource industry that no two orebodies û and hence no two development projects û are the same. So these technical issues have to be addressed to a greater or lesser extent in evaluating any resource projectÆs development potential. Not surprisingly then, technical issues tend to predominate when assessing the development potential of a project in the process typically referred to as ædoing a feasibility studyÆ. But the principal purpose of a æfeasibility studyÆ is to determine whether a development opportunity makes good business sense, not just whether it is technically possible. Resolution of technical issues is often seen as the primary focus of a feasibility study, whereas in reality, these technical issues are the basis upon which an asset delivery and business plan is built. This is not to say that technical issues are unimportant û they are a prerequisite to the demonstration of a projectÆs viability. The feasibility study process must therefore demonstrate that not only have the technical issues been satisfactorily addressed, but also that the broader commercial, economic and social issues have been considered in the development of a comprehensive business plan, which includes an assessment of the risk-reward profile of the proposed development. This paper will present a framework for the conduct of æfeasibility studiesÆ and provide guidance to minimum standards and best practice.

Jan 1, 2007

By D. R. Torgoson, Th. G. Sahama

"This paper contains some new thermodynamic data for silicates in the series Mg2SiO4-Fe2siO4 and MgSiO3-FeSiO3 and gives the results of a thermodynamic attack on the problems of stability end parageneses.. Although some data are lacking satisfactory agreement with mineralogical and petrological observations is indicated.The use of thermodynamic methods in mineralogy and petrology has been rather limited, because accurate thermal data, especially for the more complicated and more important rock-forming minerals, have been too scanty to permit any systematic application to problems in those fields. It is, nevertheless, a fascinating task to investigate to what extent the mode of occurrence and the stability relations of the minerals and mineral parageneses, as revealed by petrological and mineralogical observations, agree with predictions of thermodynamics. At the present stage of development calorimetric data are needed for most of the abundant silicate minerals.Measurement of the heats of solution in hydrofluoric acid of minerals in the series Mg2SiO4-Fe2SiO4 and MgSiO3-FeSiO3 affords a ready means of obtaining their heats of formation from the oxides. Combination of such data with entropy and heat-capacity values gives a means of obtaining free energies of formation from the oxides, which, in turn, are connected di¬rectly with stability and paragenoses.The two silicates of magnesium, Mg2SiO4 and MgSi03, occur as rock-forming constituents as forsterite and clinoenstatite or enstatite. The orthosilicate (forsterite) forms a series of isomorphic mixtures with ferrous-orthosilicate (fayalite). The continuity of this series, suggested by petrological observations, has boon proved experimentally by Bowon and Shairer.4/ The present work shows that those minerals constitute a series of perfect solid solutions - that is, a series of solid solutions for which heats of formation from the individual pure silicates, Mg2Si04 and Fe2SiO4, aro negligibly small.The metasilicates of magnesium and iron also form an isomorphic series. However, this series differs from the forstorito-fayalite series in the fact that the most iron-rich mixtures, between about En10Fs90 and pure Fs, appear to be unstable with respect to the paragenesis iron-rich olivine plus quartz. The supposed instability of pure FeSiO3 as a crystalline compound, at least at high and at moderate temperatures, is remarkable, as no crystal struc¬tural reason for such instability is apparent. The present work indicates, also, that these minerals form a perfect series of solid solutions and throws additional light on the instability question.In the following, the samples used in this investigation will be described. For each of the natural olivines and orthopyroxenes, with the exception of sample L, a chemical analysis was made of the purified and actually used fraction. All the analytical work was carried cut by Oleg v. Knorring, and the specific gravity determinations, by moans of a pycnomctcr, by Oiva Joensuu, both of the University of Helsinki, Finland. The determinations of the optical properties were made by Mrs. Toini Mikkola, of the Geological Survey of Finland."

Feb 1, 1949

By Alfredo Manrique

"Los procesos de industrialización y minería han llevado a que las empresas sean más competitivas dentro de los mercados, obligándolas a ser más productivas y exigentes y, por tanto, a reducir el tiempo destinado a los procesos de inducción y entrenamiento laboral. Estos procesos han generado jornadas extra laborales, a pesar de la fatiga y el cansancio de los operarios que conllevan a bajos niveles de concentración y atención. Como resultado, muchas empresas han propiciado el aprendizaje de comportamientos inseguros dentro de su propio entorno laboral, los cuales han sido aceptados y asumidos como parte normal de la rutina de trabajo. La autoridad reconoce su existencia, sin embargo, su abordaje frente al mejoramiento de las condiciones no es directo. "

Sep 1, 2017

By F. D. Forgeron

"ONE OF THE FIRST DOCUMENTED APPLICATIONS of soil geochemistry in the Canadian Shield was that carried out by Chisholm in the Kenora district in 1949. This survey proved successful in outlining sulphide-associated gold veins utilizing cold-extractable metals. Since then, mining companies, government agencies - both provincial and federal - and universities have conducted soil investigations. Some of the results are documented in publications, others are on open file in provincial and federal mines departments and, unfortunately, many other investigations with both successful and unsuccessful results are buried in company files or have been discarded. This paper deals with soils within the scope of chemical studies of overburden in the Canadian Shield. The subject is a broad one and some definition is required. The soil investigations discussed herein are those aimed at the testing of specific targets more or less in the source area. This definition distinguishes soil investigations from other overburden studies which commonly monitor metal accumulations at some substantial distance from the metal source. Naturally this distinction is relative, because in many instances there is overlap."

Jan 1, 1971

By R. Mier

The metals and minerals mining industry has evolved dramatically from the earliest objects ever made out of native copper circa 9,000 BC to the modern developments we see today. To better appreciate past developments and to get a sense of where the industry is heading, a brief overview of mayor industry highlights over the last 100 years will be presented, followed by a discussion on potential global scenarios and by a review on mayor industry trends.

Feb 27, 2013

By F. E. ROGERS

CUSHMAN TUNNEL No. 2 is adjacent to the Hood Canal, near potlatch, Wash. It is 17 ft. inside .diameter, about 13,000 ft., or two and one- half, miles in length, and is a part of the second unit of the Cushman power project. It connects Cushman ' Dam No. 2 and the penstocks that lead to the power house on the beach about 400 ft. vertically below the outlet of the tunnel. One shaft, 190 ft. deep, and two adits between 300 and 400 ft. long, were provided to speed up driving operations. his arrangement gave 6 working headings, which were operated 24 hr. daily. The shaft provided a manway, cageway, and skipway.

Jan 1, 1931

By Esteban Chumpitaz, Miguel Pacoticona, Ricardo Huancaya

El sistema cuenta con una alarma audible dentro de la cabina del camión que alerta al conductor en caso que el sistema detecte una condición de somnolencia. La información es almacenada en la base de datos y explotada gracias a los reportes que el sistema brinda, dichos reportes permiten identificar cuáles son los horarios en los cuales se da mayor incidencia de somnolencia, así como el récord por operador y por empresa. La instalación del sistema ha resultado bastante sencilla debido a que los componentes se concentran en un solo dispositivo que es la cámara Kinect, esta cámara consolida diferentes sensores en un solo dispositivo permitiendo su fácil instalación y adaptación por parte del operador. La implementación del presente sistema mantiene una excelente relación costo beneficio, ya que la inversión a realizar es mínima y el beneficio que se obtiene es bastante importante.

Sep 1, 2017

By Madgwick J. C, Ralph B. J

A method for the determination of microgram quantities of uranium in leachates from low grade uranium ores is described. Solubilized manium is purified by transfer to an organic solvent by a selective solvent extractionprocedure using tributyl phosphate, iso-octane, and aluminium nitrate. The organic phase is mixed with scintillation fiuors in toluene and the radioactive decay determined in a liquid scintillation counter. The method is sensitive and reproducible in the range 3-30 µg uranium.

Jan 1, 1978

Reverse Cationic Flotation of Iron Ores - Floatability of Amphiboles at Depression of Iron Oxides by Starch

Sep 13, 2010

By Julio Villón

Actualmente las empresas que utilizan software minero, necesitan desarrollar metodologias propias para hacer posible que reciba información valida en ciertos formatos, y que esta sea procesada por el software y su resultado. Este resultado se determinará en función a la calidad de la información con que se alimente al software. En ese sentido, el presente texto señala el modelo tridimensional como aquel que se ajusta al tiempo, conforme se desarrollen labores, se tomen más muestras, se hagan más sondajes diamantinos o se realice el desbroce y minado de los bancos del yacimiento.

Jul 17, 2000

By Jorge Vargas Fernández

El presente artículo describe la relación entre la cultura y los recursos mineros a través del tiempo y las acciones para mantener dicha relación, dada la importancia que tiene para el desarrollo y seguridad del Perú.

Mar 1, 1971