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By Luis Medina, Anakaren López, Diola Nuñez

Los procesos biotecnológicos como la biolixiviación, son una alternativa apropiada para resolver cuestiones críticas que afectan al mundo en desarrollo, por esta razón, se deben buscar estrategias para la manipulación de los microorganimos, de tal manera que su aplicación en la industria sea sencilla y económica. En este sentido, la aportación científica en esta investigación, es encapsular bacterias acidófilas con capacidad lixiviante, estableciendo las condiciones favorables en el proceso de secado por aspersión, así como determinar el material de pared óptimo y asegurar la viabilidad de los microorganismos.

Sep 29, 2023

By Pascal P. Percy

Dado el elevado costo de transporte que implica el traslado de mineral aurífero en la compañía minera La Poderosa, se ha elaborado un proyecto denominado "Proyecto de transporte sobre rieles" donde se garantiza el acarreo de 550 t/d a partir de 1994 y se reduce los costos del transporte a 56%. En este sentido, el presente trabajo describe la ejecución del proyecto a través del uso de túneles, chimeneas y trocha en superficie, reemplazando la os volquetes y camiones. Asimismo, el proyecto desarrolla la ejecución del túnel en forma convencional a través del metraje, logrando un control estricto de los tiempos empleados en cada operación unitaria, la utilización adecuada de los recursos, coordinación de los trabajos a realizarse y los servicios requeridos.

Nov 24, 1993

By Alfred Petrick

This study gives an analysis of the copper system byproducts and discusses the identification and classification of byproduct metals and their supply systems. Arsenic, platinum-group metals, silver, gold, selenium, tellurium, molybdenum, rhenium, uranium, aluminum, magnesium, and byproduct copper, lead, and zinc from complex ores are covered. The report describes several metallurgical systems, the marginal and incremental products costs of byproduct subsystems, industry structure and organization, and the historical data on price, consumption, and supply. Supply curves are presented for about one-half of the byproduct metals studied. The study develops a conceptual framework for analysis by reviewing the present concepts of byproduct supply and the related price theory. It gives the sources of supply of the individual byproduct metals to indicate the importance of the byproduct supply to the total supply. Mills, smelters, and refineries processing byproduct materials for their metal content are identified by geographic location and company ownership, The study also includes information on the reserves-resource base supporting byproduct output, reserve estimates, and the demand aspects of each byproduct metal.

Jan 1, 1973

By Carlos Sánchez Romero

El presente texto describe la aplicación de la implementación de herramientas hidroinformáticas para la gestión de recursos hídricos mineros en la empresa Southern. El trabajo comprende el funcionamiento de redes de estaciones meteorológicas y limnigráfícas, los sistemas SCADA para el control de la distribución de agua, así como la integración de la información dentro de un sistema de información geográfica.

Oct 1, 2013

By Edward Bullard

El presente texto señala los problemas tecnológicos, económicos y políticos que plantea la explotación de minerales de los fondos marinos. En ese sentido, las investigaciones internacionales realizadas sobre el Mar Rojo durante la última década y el proyecto JOJDES en el Atlántico proporcionan un conocimiento completo de las posibilidades del beneficio de los minerales.

Mar 1, 1975

By L. H. Harrison

In coal mines equipped with electrically driven mechanical mining equipment, the problem of protection for electrical circuits and machinery important, because the hazards of fires and explosions resulting from electrical failures is greater than in most other industries. There is need for better methods and improved protective devices for this service. Studies and tests designed to determine possible value of the short-circuiting contactor as an electrical device for coal mine service were investigated. Preliminary made to determine the operating characteristics of the device, after which tests were made under actual service in three coal mines. Ordinarily, electrical protection in coal mines is divided into three classes, as follows: 1. Overload protection that is intended to protect against damage from overheating and excessive mechanical strain due to overloading. 2. Short-circuit protection that provides a means of de-energizing the equipment instantly when an accidental short circuit occurs in the equipment or on the power system. Short cm protection tends to damage from fires and, explosions resulting in the dissipation of large amounts of electrical energy in a short circuit. 3. Ground fault protection that, in its various forms, is intended, to maintain the frames of electrical equipment at or near the same potential surfaces in contact with the earth for the purpose of safe-guarding human life.

Jan 1, 1951

By E. D. Gardner

This paper discusses small-scale lade gold mining and milling. It is abstracted from a bulletin being prepared by the United States Bureau of Mines entitled "Equipping, Developing, and Operating Small Gold Mines." Gold is widely distributed in the mountainous regions of the United States; relatively few deposits, however, can be profitably worked on a large scale. Because of the high intrinsic value of gold, ores containing this metal may be very rich; hence it is possible to mine profitably smaller bodies of gold ore than of the more common metals.

Jan 1, 1934

By Steve Hubbard, Brad Marchant, Rolando Cuadra

"Triton Mining Corporation acquired the rights to Mina El Limon in Nicaragua in 1993 by international bid. The bid included the gold operations at Limon and an exploration concession of approximately 4000 km2. Triton assumed control of operations and exploration in May 1994.The Limon mine is located in west-central Nicaragua, approximately 100 kilometers northwest of Managua. The climate is tropical, characterized by a wet season from May through October, and a dry season November through April. Gold at Limon is associated with both banded quartz and silicified breccia veins in Tertiary volcanic rocks, belonging to the lower Coyol Group. Mining is from two open pits and one mechanized underground operation. A second underground mine is currently under development for production during 1997.This paper describes the expansion of the milling facility at El Limon from a nominal capacity of 400 tonnes/day, producing approximately 20,000 ounces of gold annually, to the existing 900 tonne per day mill operation. Engineering of the new mill facility was initiated in September 1994 and construction was completed a year later."

Jan 1, 1997

By Mario Cedrón Lassus

El presente texto señala los principios de excavación de túneles y el uso de la máquina tunelera denominada TBM (del inglés Tunnel Boring Machine) en el proyecto Hidroeléctrico de Carhuaquero. Así también refiere las pautas para la selección de equipo, estimación de rendimientos y análisis de costos. Finalmente se analiza las ventajas del sistema comparada con las de método convencional para la excavación de túneles.

Nov 1, 1983

By Douglas W. Fuerstenau, Pradip Pradip

The design and development of selective flotation collectors has been the key to the remarkable success of flotation in beneficiating complex, difficult-to-process ores. Sustained research efforts in the field over the past hundred years have led to delineating the scientific basis of selective mineral flotation in terms of the crystal chemistry and the surface and colloid chemistry of minerals including their solubility, and the aqueous solution chemistry of added reagents. It is now well-established that the electrical double layer theory (EDL) is the most powerful means of quantifying the relative strength of mineral-reagent interactions in the case of nonsulfide minerals. We illustrate the utility and the power of the EDL in delineating the science underlying selective mineral flotation with the help of a few examples taken from our own work, in particular on the selective flotation of rare-earth minerals (bastnaesite) from associated semisoluble minerals (barite and calcite) using alkyl hydroxamate collectors and the flotation separation of lithium-containing minerals (spodumene) from associated alumino-silicate minerals with oleate (fatty acids). Both of these mineral separation systems are of contemporary research interest and of immense value to the industry today. Recent advances in utilizing molecular modeling computations, particularly in the context of quantifying the effect of crystal chemistry and the relative distribution of adsorption sites available on mineral cleavage planes, are also reviewed.

By H. Reimer

The rates of return on investment are examined for several major Canadian mining companies. Because we are dealing with a highly cyclical industry, subjected to widely fluctuating metal prices, rates of return are examined over a 20-year period. Conveniently, the first decade examined reflects the period when the industry enjoyed incentives to develop deposits; during the second decade, incentives were reduced and the industry became the most heavily taxed industry in Canada. The high rates of inflation since 1973 have distorted the real rates of return on investment if one considers replacement cost.

Jan 1, 1977

By Jorge Olivari Ortega

"El presente texto describe la historia del inca Huiracocha y la explotación con los filones de oro del Ritisuyo. Durante el proceso de expansión del imperio incaico, los dominios territoriales de Hatun Inca o ""Huiracocha, el octavo gobernante, alcanzaron por el sur, hasta la última población de las Charcas (en la actual República de Bolivia); por el oeste, hasta las orillas del Océano Pacífico; y por el oriente, hasta la Cordillera Nevada o Ritisuyo, donde existían riquísimos filones de oro. Así, los incas denominaron ritisuyo (de los términos quechua: riti, nieve y suyo, región) al espacio geográfico de los Andes que supera los 4,500 metros sobre el nivel del mar y está cubierto con nieves, donde muchas veces asoman o afloran filones de oro en su superficial. Los filones son depósitos de minerales con contenido aurífero que fueron explotados por los incas -particularmene por el corimayco (encargado del trabajo minero) a través de socavones, el cual consideraba la dureza del terreno y además, el curso de la estructura mineralizada (rumbo y buzamiento)."

Jan 1, 2016

By Edward H. Williams

IN the middle of the eighteenth century John Frazier and wife, Sarah Ingraham, removed from Boston, Mass., to Philadelphia, Pa., where he was held in such esteem that we find him one of the Committee which arranged the ball at Washington's inauguration. Their son John. Nalbro Frazier, was prosperous in his mercantile career and fortunate in his wife, .Anne West; who was an important personage in the early life of Professor Frazier. This cultured lady brought into the family an atmosphere of religious enthusiasm, of thoroughness and: of unity of purpose. Her son, Benjamin West Frazier, inherited her traits and displayed them during a. short and active life. Like his father, he engaged in mercantile pursuits, and was a member of the firm of Zimmerman, Frazier & Co. In their interests he lived for a short- time in Montevideo, and on his return married Isabella Zimmerman, a daughter of the head of the firm. Their happy married life was cut short by the death of Mrs. Frazier shortly after the birth of the subject of this sketch which, occurred October 3, 1841. Mr. Frazier did not long survive her, and left his orphaned sons to, the care of his mother, from whom he had inherited a lovable and deeply religious nature, an : artistic temperament and a capacity for thorough work. Whatever of these traits fell by inheritance to these children were strengthened by the influence of their grandmother, and. the purity of mind, the delicacy of sentiment, the refinement of honor, which characterized. Professor Frazier, are due to Anne West Frazier, and are generally present in the characters of all of gentle blood who have been under the sole and immediate influence of a mature and refined woman. Professor Frazier was educated at the Episcopal Academy in Philadelphia, and passed thence through the University of

Sep 1, 1905

By Luis Palomino Toledo

El presente trabajo señala el entrenamiento como necesidad básica en la industria minera, que busca aumentar su producción, reducir sus costos, así como las relaciones del trabajo. Cabe aclarar que cada curso tiene un objetivo distinto de acuerdo a un contexto particular, donde no es recomendable la trasposición de ningún programa, así hubiese dado resultados óptimos en otros casos. El entrenamiento requiere un costo económico valuado en la capacitación de un personal que evita el riesgo o despilfarro en alguna operación minera. En este sentido, es importante la función del entrenador ya que si un obrero no conoce su trabajo, es responsabilidad directa del supervisor, no haber impartido diho conocimiento. Asimismo, el plan del entrenamiento debe ser de forma integral tanto para supervisores y empleados de la zona minera. En consecuencia, el entrenamiento es una herramienta efectiva de la gerencia que mejora la producción, simplifica el trabajo y facilita la adaptación del obrero a la organización minera que pertenece.

Jul 20, 1959

By Luis Artola

El presente texto señala la estrategia de implementación, la estructura y los principales entregables para lograr la integración de tres aspectos de la gestión de la organización: la calidad, la seguridad, salud y la protección del medio ambiente. Para ello, se utiliza el sistema de calidad ISO 9001 como modelo de mejora continua que integra a los otros dos sistemas de gestión (de seguridad/salud y medio ambiente) de forma que enlaza con el modelo de gestión de proyectos (del PMI) para la realización de los trabajos.

Apr 1, 2015

By P. H. Tumialán

El presente trabajo señala el proceso de mineralización del yacimiento de plata San Juan de Lucanas, Ayacucho, cuyas vetas NE de cizalla y juego NNE de tensión son producidos por fuerzas de compresión NNE- SSW. Asimismo, se describe su fisiografía, petrografía y petrología, geología estructural, estratigrafía histórica, geología económica, textura, zoneamiento, alteración hipógena de cajas, persistencia de mineralización, comparación de otros yacimientos, controles de mineralización, las reservas de diciembre de 1979, concluyendo con las posibilidades de mineralización de plata a través de un plan sistemático de exploración.

Oct 14, 1980

By Duberly Huisa

En la actualidad la tecnología de simulación numérica de fluidos tridimensionales a través de computadoras personales, se ha desarrollado a un ritmo acelerado, estas herramientas modernas que se denominan CFD (Computational Fluid Dynamics) son capaces de simular y analizar el comportamiento hidráulico de estructuras complejas, ya sea para un nuevo diseño o correcciones y/o mejoras de estructuras hidráulicas existentes, motivo por el cual este articulo da a conocer y saber cuáles son sus: técnicas, bondades, capacidades y limitantes.

Sep 1, 2017

By Eduardo Simian

El presente texto señala las condiciones adecuadas de las inversiones respecto al cobre en Chile. Así también se define las cinco materias que definen la política del Gobierno para el desarrollo de la industria cuprífera chilena como la idea de refinación, franquicias y garantías de las inversiones, intervención en el comercio, adquisiciones en el país y las sociedades mixtas.

Nov 1, 1965

By John D. Rockaway

Failure of the mine floor supporting coal pillars frequently occurs when the subcoal strata include "underclays" or other low strength strata. The failure process has been studied to define the response of these materials to applied coal pillar loads and to determine the applicability of bearing capacity analysis to evaluate unsafe conditions. The study has been accomplished through an investigation of both the intact and insitu geotechnical properties of the subcoal strata and through the installation of floor movement monitoring instrumentation. The results of these studies have indicated that both the shear strength of the underclay and the stratigraphy of the subcoal strata must be considered in the analysis. The shear strength was the major controlling factor determining the ultimate load carrying ability of the materials, but the thickness and stratigraphic position of the weak layers influenced the mechanism of the failure process. The methods of bearing capacity analysis were used to define pillar stability that included provisions for taking into consideration a two-layer system. Conditions assumed for a coal mine where a weak underclay overlies firmer strata. The results of the analysis compared very well with observed mine conditions, indicating marginal conditions in areas of the mine which later experienced pillar support failure. In addition, a "heave factor" was derived to predict potentially unstable floor conditions in the mines studied in detail.

Jan 1, 1979

By Hernani Mota, Eleonardo Lucas, Christ Barriga

Este trabajo técnico presenta los estudios realizados para una caracterización física, mecánica y mineralógica del macizo y material rocoso presentes en una mina en la sierra del Perú, con énfasis en el estudio de las estructuras mineras (tajo, pila de estéril y pila de lixiviación). El principal objetivo fue determinar la influencia que tiene la alteración del pH cuando los agentes de meteorización como las condiciones climatológicas (temperatura y precipitación) someten al material y que puede causar imprevistos en las obras de ingeniería realizadas en minería.

Sep 29, 2023