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By Feria Bengoa

El creciente interés del público sobre los problemas ambientales, la satisfacción de los clientes y la seguridad minera, ha generado un alza de leyes en el sector minero e industrial, nuevas ONG y la búsqueda de productos, materiales y procesos compatibles con la preservación de los recursos naturales y cada vez más seguros. En ese sentido, el presente trabajo muestra la estructura del SIG basada en el ciclo conocido de Shewhart (PDCA), y que constituye la espiral de mejora continua de las normas internacionales ISO 9001, ISO 14001 y OHSAS 18001. La base comprende 17 procesos que conforman el SIG según la filosofía del PDCA, los que han sido agrupados como: Política, Planificación, Implementación, Evaluación, Mejora y Revisión de la Alta Dirección. La implementación del SIG que se está realizando en la Fundición de Cobre, asegura la calidad del proceso productivo, estandarizar las mejores prácticas operativas a través de instrucciones de trabajo y procedimientos, motiva y forma a todo el personal de la empresa, cumple con la legislación y mejora la seguridad y salud ocupacional de todo el personal.

Sep 12, 2005

By E. LaRocque

"Long term contracts requiring delivery of 6,000,000 pounds of U308 per year to its customers have made it necessary for Denison Mines to expand its milling capacity from 7,100 tons per day to 15,000 tons per day.Previous papers (1) and (2) described the old leaching and product recovery practice. The flowsheet briefly includes a crushing and grinding circuit, sulphuric acid leaching in a Pachuca plant, liquid-solid separation with wash thickeners and two-stage drum filtration, concentration and purification by moving bed ion exchange followed by two-stage precipitation to produce an ammonia yellowcake.No. 1 Shaft ore, about 4,000 tons per day, will be processed through the truck dump into the old crushing and grinding plant and through the old leaching plant. Ore from Stanrock (No. 3 shaft) will be hauled by truck and also processed through the truck dump as No. 1 shaft ore. Beginning in 1982, ore production from Stanrock will gradually increase until 1985 when some 3,000 tons per day will be milled from the source.A new 8,000 ton per day circuit was designed and constructed to increase the milling capacity to 15,000 tons per day. The new circuit is separate from the old one except that it coins together for the precipitation and tailings neutralization sections of the plant. The feed to the new plant will be from No. 2 shaft.The flowsheet is much the same as the old plant with the exception of the grinding circuit and the ion exchange plant. A semi-autogenous grinding (SAG) plant, unique in the Elliot Lake area, has been installed rather than the conventional crushing and grinding plant; the ion exchange plant is the stationery bed type.This paper describes the major equipment installed for the expanded grinding and hydrometallurgical plant."

Jan 1, 1982

By H. C. Fowler

Technical developments in the American petroleum industry as regards exploration, drilling, production, and transportation were characterized by many anomalous conditions during the half decade 1914-19. A review of the literature of that period discloses the striking fact that individual geologists, engineers, and other technologists were surprisingly well versed concerning the occurrence of natural hydrocarbons and methods of extracting them and were acquainted with many of the physical and chemical characteristics that influence the behavior of fluids in natural reservoirs. However, the industry as a whole knew little of the correct application of recognized fundamentals; indeed, judged by present standards certain expediencies of self-styled "practical' operators seem cumbersome, if not evidences of ignorance.

Jan 1, 1941

By M Scott, J J. McEwan

Silver and silver alloys tarnish readily by the formation of tarnish on the surface when exposed to a wide range of sulphur-containing atmospheres. This tarnish is unsightly and undesirable and can be removed either with a silver polish or a chemical dip. Polishes are, however, not suitable for irregular and embossed surfaces such as on coins, medallions and jewellery items, because of uneven removal of the tarnish layer and excessive wear. Successful tarnish protection can be achieved by either storing the items away from the aggressive atmosphere or by coating/treating the exposed surfaces with a protective layer. Storage is feasible for collections but is not suitable for items that are handled or worn regularly, such as jewellery. A number of commercial coatings and treatments have been developed, but to date there has not been a systematic evaluation of tarnish protection. This paper details the performance of a range of generic coatings in an accelerated tarnish test. The degree of tarnish was evaluated by means of loss in reflectivity and change in colour. Four coatings/treatments improved the tarnish resistance of silver by more than tenfold. These include an organic lacquer, rhodium electroplating and an organic self-assembled monolayer (SAM) conversion coating. Research is continuing to optimise these coatings. Keywords: silver alloys, tarnish resistant coatings, silver polishes.

Jan 1, 2006

By Jack E. Brockway

As tunnel boring machine technology has expanded, so has its range of application. Tunneling machines (TBM's) are tackling tasks today that fifteen years ago were considered "inappropriate". A case in point is incline/decline TBM boring. An incline or decline bore presents peculiar design considerations that differentiate it from a horizontal bore. This paper reviews those design considerations as they apply to TBM's, backup, muck handling and other tunneling subsystems. In addition, several abbreviated case studies are presented. By the review of real life tunneling techniques as well as design considerations, the "appropriateness" of TBM incline/ decline boring today becomes apparent. INCLINE Introduction In contemplating the impact of incline versus horizontal tunnel boring system design, the obvious consideration is gravity. Up-hill boring can be quite different than horizontal boring. Muck, water and machine weight all tend to slide down the incline. In addition, hydraulic and lubrication systems if unaltered, will find their fluids pooled in the lower corners contentedly ignoring such higher elevation items as gears and bearings. In order to address this inherent gravity problem, a review of

Jan 1, 1983

By Víctor Barrientos

El presente trabajo es un estudio realizado donde se determina la pérdida de ingresos de una empresa minera, producto de la detención de camiones y cargadores frontales en una faena minera a cielo abierto. El cálculo de esta pérdida de ingresos se realiza a través de un modelo que estima el volumen del movimiento de roca de la mina y los ingresos que este genera en función de la disponibilidad y rendimiento de los camiones y cargadores, y su interacción conjunta.

Sep 1, 2015

Jan 1, 1902

By Marc Arpin

La Bolivie possède tout pour réussir. Son vaste territoire de plus d'un million de km2 et qui occupe une position stratégique au coeur du continent sud-américain recèle des ressources naturelles (forêts, minéraux, gaz naturel, etc) variées et abondantes. Elle a une frontière avec pas moins de 5 pays dont le géant que constitue le Brésil ainsi qu'avec l'Argentine, l'autre puissance régionale. Pourtant, malgré tous ces atouts, la Bolivie demeure l'un des pays les plus pauvres du continent. Ce paradoxe n'est nulle part mieux reflété que dans le secteur minier. Celui-ci fait face à une situation de crise en dépit d'une tradition minière de plus de quatre siècles et d'un potentiel géologique indiscutable ayant conduit à la découverte et à l'exploitation de fabuleux gisements d'argent et d'étain. Les habitants des districts miniers vivent dans des conditions de pauvreté extrême et les indicateurs de développement humain de ces régions sont parmi les plus bas en Amérique du Sud. La Bolivie réussit difficilement à attirer les compagnies minières alors que, chez les voisins, et particulièrement en Argentine, qui n'a pas de tradition minière, les investissements miniers majeurs affluent. Dans cette conférence, nous chercherons à expliquer les causes de cette situation et proposerons des solutions possibles.

May 1, 2001

By E. E. Krist

El desmuestre de un criadero tiene un buen número de finalidades. En la fase inicial es necesario definir los límites del yacimiento y el contenido o ley del mineral hasta el punto de que pueda ser establecido si es, de hecho, un yacimiento económico. Igualmente, las muestras tienen que ser generadas de forma tal que las evaluaciones geológicas y metalúrgicas puedan ser Ilevadas a cabo. Finalmente, cuando se conoce la suficiente información concerniente a la geología, mineralogía y metalurgia, puede ser desarrollado un método minero y su plan, y construidas las oportunas plantas metalúrgicas para procesar los minerales a medida que se encuentran disponibles1. Con las minas actuales grandes y complejas a cielo abierto los métodos de desmuestre único deberían de ser inadecuados. La perforación por diamante, la perforación por percusión, pozos subterráneos y galerías, juegan todos conjuntamente un papel parcial en la definición total del yacimiento. En la mina Twin Buttes, de la Anamax Mining Company, el desmuestre y la definición del yacimiento conducirán eventualmente a la existencia de tres plantas metalúrgicas de proceso y, quizá a, una operación de minería subterránea. Fue puesto en marcha un concentrador de sulfuros de 30.000 tons. por día en Septiembre de 1969 y una planta de 10.000 toneladas diarias de lixiviación de óxido fue puesta en servicio en Mayo de 1975. La finalidad de esta presentación es la de exponer históricamente el desmuestre del yacimiento que ha sido Ilevado a cabo en Twin Buttes, describir brevemente el criadero, y exponer los métodos analíticos corrientemente utilizados para ayudar al geólogo, al metalúrgico y al diseñador de la mina en sus respectivas evaluaciones.

Jan 1, 1982

By Rick Moignard

Relationships between Information Technology providers and their clients are often segmented according to job specific tasks. As a consequence, technology providers tend to focus on automating repetition and complexity, resulting in software that improves individual productivity while failing to address the interdependency of mining functions. For this reason, technology vendors like Gemcom are following partnership approaches with their clients, engaging corporate and operational stakeholders to better understand mining business objectives. This presentation examines some of the approaches that help foster the development of solutions that leverage the information produced during mine operations to improve downstream process control and tactical decision support.

May 1, 2006

By Hernando Labarthe

El Banco Minero del Perú fue creado por la Ley 9157 con la finalidad de impulsar el desarrollo de la minería nacional. Su cumplimiento ha representado la creación de una política de inversiones instalándosr centrales de benefico para minería metálica en diversas regiones de la República. Sin embargo, los proyectos culturales contemplan el aporte de otras entidades financieras, para lo cual el Banco cuenta con organismos de control preparados y que tienen la suficiencia económica ,legal y necesaria para garantizar a los inversionistas extranjeros. En este sentido, el presente artículo señala la función del Banco Minero en la instalación y operación de sus plantas de beneficio y así como las ventajas,e instalaciones, organizando las proyecciones futuras de esta actividad.

Jan 1, 1957

By A. Esterhuizen, S. Essack, H. Joubert, N. Fowler

Tenova Pyromet has developed innovative technologies for copper smelting and electric slag cleaning furnaces. Based on client feedback and requirements, innovative designs have been developed to address key design areas and improve furnace reliability, operability and hygiene. These developments include the NovaLance™ lance system to prevent lance bending on top submerged lance furnaces, the SlagFlo™ slag tapping flow control device to better control bath levels and tapping rate for granulation, and an electrode seal for improved sealing directly onto the electrode casing to allow water-cooled electrode components to be located above the furnace roof. The potential application and benefits of these innovative designs are discussed. INTRODUCTION Tenova Pyromet has a long history in the engineering and supply of innovative electric furnace and related equipment for the base metals and platinum industries. Recently Tenova Pyromet has used its furnace equipment design experience to engineer innovative solutions for top submerged lance (TSL) furnaces, and potentially other furnace technologies. These equipment design solutions are developed to address specific operating challenges and operator requirements. Three of these innovative equipment developments are discussed in this paper. First the NovaLance™ lance technology to prevent lance bending during operation in TSL furnaces, such as used for primary copper smelting, is described. Lance bending has been identified as a significant problem for TSL furnace operators as it causes down time and affects furnace availability. The SlagFlo™ device to control the slag flow rate during tapping has been developed based on specific requirements in the mineral wool industry. The SlagFlo™ device can be used to control slag bath levels in primary smelting, converting and slag cleaning furnaces for base metals including copper. In addition, it can be remotely activated for the safe closing of slag tapholes located upstream from a water granulation system. Finally, Tenova Pyromet developed an electrode seal that seals directly onto an electrode surface. This is a special requirement related to base metals and platinum electric smelting and slag cleaning furnaces where furnace operators prefer to keep the water-cooled electrode equipment above the furnace roof. The seal can be used to seal directly onto the potentially hot and uneven surface of Söderberg, pre-baked and graphite electrodes.

Jan 1, 2019

By Pedro Hugo Tumialán de la Cruz

Dado que es difícil determinar el potencial minero de un yacimiento durante los primeros meses, es necesario la aplicación de un sistema de exploración geofísica que prevea el estado de mineralización a futuro. En este sentido, el objeto del texto radica en señalar los problemas encontrados en algunas zonas mineras del Perú, así como las posibles soluciones para este problema, a partir del uso de este sistema. Los casos a analizar son: exploración en yacimientos de cobre de la mina Acotambo, la exploración en el sistema polimetálico, la exploración en el distrito minero de Caylloma y la exploración en el yacimiento Pasto Bueno (Ancash).

Nov 20, 1978

By Jonathan Bishop, Jacob Croall, Wilder Sánchez

El presente trabajo logra demostrar que los efluentes ácidos mineros se pueden tratar directamente a través de membranas de Osmosis Inversa (OI), logrando cumplir con los más altos estándares de calidad de agua tanto Nacionales como Internacionales. Este es un uso Innovador de la tecnología de membranas para el tratamiento de aguas acidas de minería.

Sep 29, 2023

By Jorge Maldonado Villa

Se desarrollaron materiales compuestos de matriz polimérica para toberas en cohetes; con dos zonas: una térmica para soportar elevadas temperaturas de combustión y una estructural que resista los esfuerzos generados. La zona térmica se elaboró con materiales de comportamiento ablativo, probados a temperaturas de hasta 2950°C durante dos minutos, los cuales fueron reforzados con polvo cerámico y/o subproducto de la industria siderúrgica (cerámico 2). Con base en los resultados obtenidos del comportamiento de térmico y de conductividad térmica del material ablativo, se construyó la zona estructural en materiales compuestos fibroreforzados (vidrio y carbono) con matriz polimérica. Los moldes se diseñaron en SolidWorks y se fabricaron por prototipado en ABS rápido y se elaboraron machos disgregables en poliuretano. En la zona térmica se usó un procedimiento de vaciado con vibración con diferentes tipos de matrices (poliéster, vinilester, caucho silicona) y de laminación para la zona estructural. Se evaluó el desempeño mediante simulación de las condiciones reales de operación mediante llama de oxicorte y quemador de ACPM, observando el efecto en la pérdida de peso, espesor, diferencial de temperatura, cambio de propiedades mecánicas, etc.; encontrándose un positivo comportamiento del sistema con matriz de resina vinilester reforzado con polvo cerámico 1 y buenos resultados con cerámico 2, así como una estabilidad en la zona estructural construida con fibras de vidrio y carbono. Substituir todo o texto de orientação deste Template pelo conteúdo de seu trabalho. Inserir o texto com no máximo 1.500 caracteres (200 palavras), sem uso de parágrafos. Deve conter, de maneira concisa, o objetivo, a metodologia, os resultados e as conclusões do trabalho.

Aug 17, 2017

By Bernard Lewis

This report summarizes the fundamental research and technical studies conducted by the Explosives Branch of the Bureau of Mines from July 1, 1943, to June 30, 1949. It is the thirteenth of a series of annual reports, which have aimed to bring to the reader a resume of the research results that have appeared in published form during each fiscal year. The work of the Explosives Branch covers a number of activities - explosives research, explosives testing, flame and combustion research, flammability of gases and vapors, dust-explosions research, and technical studies in the experimental mine. An important part of the work of the branch is fundamental research to advance our knowledge and understanding of explosion processes. Considerable emphasis has been placed on studies of ignition and flame stabilization, as it is felt that an understanding of these processes should assist materially in alleviating explosion hazards in coal mines. The results are also finding important application in the development of jet propulsion. Studies of the explosibility of gases, vapors, and dusts saving thousands of lives and are preventing the destruction of much property. In innumerable instances in which potential explosion hazards exist, safe operating procedures have been recommended from data taken in the Laboratory. Aware of the value to national security of research results of combustion, flame, and explosion, the Army, Navy, and Air Forces are actively supporting important phases of this fundamental research.

Jan 1, 1950

By Marino Gaspar

El presente texto tiene como objetivo la mejora de gestión de mantenimiento de la flota, el aumento de la productividad y eficiencia de los scoop en el proceso de monitoreo de la mina Los Quenuales de la unidad minera Yauliyacu. Para ello, se desarrolla SIMORES, un sistema que recolecta toda la información accesible de los scoop, para que se tenga una perfecta gestión de la flota de scoop con la máxima productividad y eficiencia. Dicha información genera datos como: tiempo de uso del motor, consumo del combustible, uso de los cambios de la transmisión, información de servicio, etc que permite monitorear y administrar mejor el equipo, haciéndolo más productivo.

Sep 24, 2008

By R. Franfield

This paper describes a situation that many drilling and blasting contractors have found themselves in – a client?s fear of the use of explosives. In the summer of 2007 Blasting Services Ltd was asked to undertake some drilling and blasting work in an abandoned quarry that was being restored for a housing development. Previous quarrying operations had left a series of overhangs that were considered unsafe and required removing. The site contractor considered that the best and safest way to carry out this work was by drilling and blasting. Blasting Services Ltd, with the technical assistance of Exchem Explosives, designed a drilling and blasting regime to accomplish this work with a series of trim blasts. The design took into account the close proximity of a structure in very poor condition and the imposed vibration limit of 6.0 mm/s (0.24 i.p.s.). The faces were profiled, holes drilled and explosives ordered. A few days before the first blast was due to be carried out the client decided that the poor condition of the nearby structure meant that the use of explosives could not be permitted. This decision was made despite the blast design indicating that the vibration level would be well below the 6.0 mm/s (0.24 i.p.s.) limit.

Jan 1, 2009

By Ke Yang

In Chinese coal mines, extraction of deep, highly gassy soft coal seams sandwiched between soft floor and soft roof in complicated geology is commonly encountered. How to safely and efficiently excavate such seams is a very significant and important problem. It has been a focused research area in recent years. By combining the characteristics of fully mechanized longwall mining methods such as large cutting height and mining along the dip, an integrated method and technologies for the Zhangji Coal Mine were developed. This technology includes the design of a complicated geological exploration system, optimization of mining method and working face parameters, control of rock pressure and high levels of gas, reliability model of the production system, and selection and compatibility of equipment. Engineering practice shows that the integrated technology was successful in mining these complicated seams. This study not only enriches the mining method, but also improves the coal mining practice, especially ensuring both safety and productivity under complicated geological conditions.

Jan 1, 2009

By Robert Thurner

The underground car park "Admonterhof in the historical centre of Graz is an example for the technical and economical success of a complicated structural design using a concept on the basis of the observational method. The intention to built a 20 m deep excavation beneath a protected monument was accompanied by some essential issues: the preservation of the existing state avoiding extensive displacements by means of a girder grid of reinforced concrete, its support on large bored piles and small steel-tube piles with possible active compensation of differential settlements, the excavation support in none built-up areas with secant bored piles, the underpinning of existing buildings with different structures by means of jet grouting. Furthermore the hydraulic gradient and the permeability of a rock formation in a part of the excavation had to be explored with the purpose to control the inflow of groundwater with a level difference of more than 10 m.

Jan 1, 2006