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By José Luis Calderón, Percy Arrosquipa

Compañía Minera Poderosa ha identificado una interesante oportunidad de generar valor y de mejorar tanto el clima laboral como el de relaciones comunitarias mediante el proyecto descrito en este artículo. El proyecto se orientó a motivar la incorporación de prácticas de responsabilidad social, tanto entre proveedores de bienes y servicios, como entre empresarios mineros artesanales en proceso de formalización. Como ejemplo, se analiza el caso del cofinanciamiento de la obra “Mejoramiento del sistema de agua para consumo humano del anexo Pueblo Nuevo”, que benefició a 195 familias con un servicio de agua de calidad las 24 horas del día. De este modo, se corrigió una fuente de conflictos sociales y se materializó una alianza para el desarrollo local entre la mediana minería y la minería artesanal. Por su parte, Asociación Pataz entregó certificados de donación, deducibles del Impuesto a la Renta, a los aportantes.

Sep 30, 2017

By W. Mackenzie

The development of a resource project inevitably requires the investigation of a vast range of issues across most engineering disciplines - mining, metallurgical, chemical, civil, electrical, mechanical and environmental - as well as the geosciences. It is also a characteristic feature of the resource industry that no two orebodies - and hence no two development projects - are the same. So these technical issues have to be addressed to a greater or lesser extent in evaluating any resource project's 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 `doing a feasibility study'. But the principal purpose of a `feasibility study' 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 - they are a prerequisite to the demonstration of a project's 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 `feasibility studies' and provide guidance to minimum standards and best practice.

Jan 1, 2007

By W. F. Faragher

The principal equipment in the catalyst plants at Ludwigshafen-Oppau was inspected and is presented in the form of flow sheets for the manufacture of four of the principal catalysts. The equipment is in many cases of special design rather than stock items that was built by the company and modified in the coarse of the growth of the high-pressure synthesis of hydrocarbons in Germany. It is believed that if the manufacture of catalysts were to be undertaken elsewhere, the selection of equipment for the operations involved could be made successfully from the guidance furnished by this rather general report. Five additional catalysts are described, also. II. CATALYST 5058 FROM FRESH TUNGSTIC ACID In a supply tank of about 2,000 liters capacity, 500 kg. of tungstic acid (W03.H2O) that contains about 92-93 percent of W03 is dissolved at 60-70° C. in 1,500 liters of mother liquor. The solution is-effected by stirring for about 1-1/2 hours. The mother liquor is obtained from a previous, lot of catalyst and is first adjusted to a concentration of 13 percent 1H3 by passing in gaseous ammonia. The solution is allowed to stand without stirring for 1 hour, then is pumped into the saturating vessel through a cloth filter (three-quarters hr. to one hr.). The saturator is purged with H2S and thereafter the solution, which has been cooled to about 75° C., is heated in an atmosphere of hydrogen sulfide with stirring to about 70° C. This charge is slowly cooled to 50°, and then more rapidly to about 20° C. (time of cooling 6-7 hours).

Jan 1, 1946

By C. Vera, G. Alí

La Geología de Contonga está conformada principalmente por secuencia Sedimentaria del Cretáceo desde el Grupo Goyllarisquizga hasta la Formación Celendín. El Yacimiento tipo skarn distal Contonga de cuerpos irregulares está emplazado dentro de la Formación Jumasha compuesta de calizas compactas de gris claro a gris oscuro con presencia de brechas en la base, asociado a fallas a lo largo de los planos de estratificación. Este depósito se encuentra asociado a un ambiente de margen continental relacionado a magmas calcoalcalinos “I” (stock pórfido dacitico) con altos contenidos de granates/piroxenos y mineralización de Zn-Ag-Pb-Cu.

May 1, 2008

By Donald O. Capstick

The local geology, the lack of recorded mining activity, and our field investigation and associated sampling indicate a low potential for mineral resources. Claim records and the literature review failed to show any lode or heavy mineral placer mining claim locations that are definitely in the area or anomalous mineral concentrations in the study area. Field investigations revealed no claims, prospects, or mineralized areas.

Jan 1, 1982

By Frank B. Fulkerson

Barge traffic on the Nation's inland waterways over the past 15 years has been increasing at a rate much faster than intercity freight traffic by all modes, largely due to the growing consumption of mineral commodities, development of more powerful towboats and large and more specialized barges, improvements to loading and unloading facilities, and competition among bargelines for contract shipment of bulk commodities. The Bureau of Mines, in a study to determine barge traffic projections for inland waterways in the South-Central States to the year 1980, gathered data on origin-destination patterns by commodity, quantity moved, equipment used, and rates charged; the trend of each of these factors over time; and the extent of competition between water trans-port and other means of transportation. The Mississippi River and the Gulf Intracoastal Waterway, which together carryover half the Nation's barge traffic, are major carriers of coal, crude petroleum, steel, marine shells, sulfur, salt, cement, and alumina. Greater quantities of these products will be transported by barge; however, oil pipe-lines and unit trains for coal are expected to limit increased barge traffic of these two commodities. Increasing quantities of fertilizer materials will be transported upstream. Although congestion at certain locks is a current problem, the Mississippi River below St. Louis and other open-river stretches have the capacity to handle the increasing number of barges for the foreseeable future.

Jan 1, 1969

By Dennis R. Jr Bell

Before beginning any site development or mineral extraction activity, it has been well documented that it is first prudent to gain an understanding of the prevailing geologic conditions.Whether it’s identifying the depth to type of bedrock, or determining the quality and quantity of the in place mineral deposit, these factors should always be considered in a project’s fatal flaw analysis. In situations where there is limited subsurface information, geologic models have been proven to be one of the most valuable and cost-effective tools used by the developer and/or his consultant.

Jan 1, 1997

By B. H. Grimes

El presente texto describe el equipo, las técnicas de fotografía aérea y los nuevos procedimientos para interpretar los resultados de la exploración de recursos minerales en el país. Dicha técnica comprende dos tipos principales de fotografía: vertical y oblicua. La fotografía vertical es un mapa pictórico y da una visión en planta del terreno, mientras que la oblicua, se aplica cuando se desea una interpretación fotográfica detallada en gran escala -particularmente al estudio de bosques cuando la cubierta de los árboles enmascara los detalles de la fotografía vertical. De otro se refieren las técnicas y los equipos fotográficos, la estereofotografía y la detección remota, la cual permite obtener más información que con la fotografía usual, puesto que aprovecha sólo la parte visible del espectro.

Mar 1, 1974

By Terry R. Neumann

The Olallie RARE II study area has volcanic cinder deposits with a sow potential for development. No mining claims or prospects are known within the study area, and except for common construction materials such as volcanic cinders and stone, no mineral deposits were identified. An evaluation of the geology indicates that metallic mineral deposits are unlikely to exist. No significant metallic concentrations were reported in samples from the area. The only resources in the study area are about 30 million cu yds (23 million cu m) of cinders in three cones. The cinder deposits in the study area cannot compete economically with enormous deposits of similar material in more accesible areas closer to markets. At the present rate of consumption, resources outside the area are adequate far into the future. The geothermal potential of the study area is being evaluated by the U.S. Geological Survey.

Jan 1, 1983

By Konstantin Lukashev

En los próximos cincuenta años, la humanidad necesitará de recursos minerales como el hierro, manganeso, cromo, níquel, cobre, plomo, zinc, oro, plata y platino para su desarrollo y sobrevivencia. Por tal motivo, el presente texto describe alternativas a través de la ciencia y la tecnología donde se busca descubrir nuevas formas de utilizar otras fuentes energéticas naturales. Es necesario que se realizen progresos en la domesticación de la energía nuclear para la solución de problemas energéticos mundiales. De otro lado, se describen los recursos con lo que cuenta cada país capitalista en el mundo y su dependencia de las importaciones de otros como es el caso de Estados Unidos, Japón, República Federal Alemana, Reino Unido, Francia y otras naciones de Europa occidental.

Jul 1, 1975

By F. J. Sotillo

The reduction in energy consumption has been always important for beneficiation plants. Also gravity separation processes have gained lately great importance due to environmental concerns, especially in the gold and silver Industries. In this sense, the paper point out how to reduce the energy consumption in grinding, and increase efficiency in both grinding and gravity separation are of utmost importance to optimize the use of the country’s resources. For these purposes, chemical additives, such as rheology modifiers have shown great potential, and deserved careful consideration.

Sep 9, 2007

By D J. Brake

There has been a strong trend over the past decade in hard rock mines towards the use of very high powered auxiliary (or secondary) fans; in many mines, the installed power for the secondary ventilation system now exceeds that of the primary ventilation system. This also reflects the trend to use two-stage auxiliary fans pushing air into a single ‘trunk’ duct that in turn splits into multiple branches with multiple outlets feeding multiple workplaces. This often produces a poor result in terms of face flows due to the high resistance, high leakage and badly managed duct outlets, as well as high fan capital and operating (power) costs, which in turn also results in a higher cost for the underground power reticulation/distribution systems. This paper explores the reasons why this trend exists and what ventilation practitioners can do to utilise less expensive systems that simultaneously deliver better workplace conditions. It includes a case study.CITATION:Brake, D J, 2017. Auxiliary ventilation design – why and how mines waste so much power on inferior systems, in Proceedings Australian Mine Vent Conference 2017, pp 27–34 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By R. Curtis

To achieve compliance with 2015 EPA Tier 4 Final regulations, which permit only around 10% of Tier 3 particulate matter (PM) and NOx emissions, a number of technologies are being implemented. Use of a fuel borne nanoparticle combustion catalyst reduces the level of PM and unburned hydrocarbons exiting the combustion chamber, alleviating the burden on downstream exhaust after-treatment systems. The impact of an iron-ceria combustion catalyst (GO2) on carbon oxidation kinetics and on diesel engine emissions is presented. The iron-ceria nanoparticles catalyze carbon oxidation at lower temperatures and increase the oxidation rate by a factor of 18 at 400 °C. Engine tests on a generator powered by a John Deere Model engine and field tests on a Cummins ISC 330 tractor truck and CAT 3508B propulsion engines are presented. Use of GO2 resulted in a reduction in PM10 (particulate matter under 10 um) emissions of up to 26% and a hydrocarbon emission reduction of up to 41%. NOx emissions did not increase in these trials and the amount of change depended on engine type. Application of this fuel borne technology for emissions reductions in mining equipment offers significant benefits.

Feb 27, 2013

The efficiency of a coal mine ventilation circuit is usually measured by the ratio of the sum of the face quantities divided by the quantity supplied by the fans. Other types of systems use the power delivered to the power supplied to measure efficiency. This paper argues the case that the current measure may be inadequate and that by also looking at the power ratio, ventilation may be better managed. Problems associated with failing ventilation systems would be highlighted earlier so that crisis management could be avoided.

Jan 1, 2009

By Alberto Benavides

El presente texto señala la evolución del sistema de energía eléctrica en diversos sectores entre el período de 1968-1977 y así evaluar su demanda en el futuro a través de fuentes hidráulicas. Actualmente, el potencial hidroeléctrico ha sido establecido en 29.257 MW en la cuenca del Pacífico y de 176,287 en la del Atlántico. Del potencial total se considera como factible de desarrollar técnica y económicamente 58,000 MW, lo cual es amplio para los requerimientos de la minería, ya que la actual potencia generada es sólo de 3% del potencial total.

Nov 1, 1980

By L. Vela

Panoro es una empresa de exploraciones canadiense con un portafolio de 11 proyectos de Cu-Au de gran escala ubicados en la provincia del Batolito de Andahuaylas-Yauri, en Apurímac y Cusco. El proyecto Cotabambas es el más avanzado de ellos y consta de un sistema de pórfidos de Cu-Au (Ag, Mo), a veces emplazado en un ambiente netamente ígneo y volcánico (Cluster 1) y otras veces en el frente de calizas y areniscas del grupo Yura (Cluster 2) donde además se genera mineralización tipo Skarn. Los Clusters 1 y 2 presentan trabajos de mapeo, muestreo de rocas y geofísica, sin embargo, fuera de ellos existen otros 4 prospectos tipo skarn que requieren más estudios.

May 1, 2008

By Lee Sieng Kai

This paper presents the result of the analysis of strain-dependent concrete modulus from full-scale static axial compression load tests conducted on more than 200 instrumented cast-in-place barrettes and bored piles over the past 12 years, covering commonly adopted grades of concrete for heavy foundation construction in Malaysia and Singapore. The concrete modulus values, Ec, analysed were directly back-calculated from the material of the instrumented test piles by means of placing a layer of vibrating wire strain gauges near the pile head region. The best fit curve for back-calculated concrete secant modulus versus measured axial strain follows non-linear behaviour for both categories of test pile samples analysed. The result of the analysis seems to suggest that using average constant modulus value would generally lead to a significant error in load distribution computation, particularly at high stresses region.

Jan 1, 2006

By Luis Miguel Panduro Robles

"La aireación forzada busca acelerar la cinética de extracción del cobre en el cobre a través del oxígeno del aire al ion ferroso que se encuentra presente en las soluciones de lixiviación formando el ion férrico; elion férrico formado de esta manera oxida a su vez al cobre metálico (de la calcosita y la bornita) o al azufre (de la covelita primaria o residual) reduciéndose a ion ferroso. El ion ferroso formado se vuelve a oxidar conoxígeno y así continúa el ciclo hasta que todo el mineral sulfurado ha sido oxidado. En ese sentido, el presente trabajo describe las evaluaciones realizadas en Cerro Verde que analizaron el requerimiento de óxigeno en una pila industrial, la determinación del diámetro de orificio óptimo para las tuberías de aireación y el tipo de tubería más adecuado para la aireación."

Jul 31, 2003

By José Calderón

Gracias a que Poderosa tiene la categoría de empresa tractora (de acuerdo con definición de Produce, que se caracteriza por su capacidad de arrastre y efectos multiplicadores al movilizar un conjunto amplio de empresas en torno a su cadena productiva), logró el cofinanciamiento del proyecto “Mejoramiento del sistema de agua para consumo humano del anexo Pueblo Nuevo”, para el que Poderosa aportó el 30% y un total de 19 empresarios mineros artesanales, el 70% restante del financiamiento requerido. El presente proyecto (RS Compartida) tiene por objetivo incorporar en prácticas de responsabilidad social a los mineros artesanales que están en proceso de formalización y trabajan con Poderosa.

Sep 20, 2019

By Alberto Buendía

Con el objetivo de mejorar las condiciones de productividad de Southern Perú Copper Corporation, la empresa desarrolla actividades orientadas a optimizar sus resultados de producción y operación. En ese sentido, el presente texto señala los cambios trascendentales aplicados en la planta concentradora. El primero, refiere al cambio de inclinación de los hidrociclones de la molienda convencional de 30º a 20º (con respecto a la horizontal) con la finalidad de optimizar la capacidad de molienda; y el segundo, es el de reducir el porcentaje de sólidos en la pulpa de alimentación a la flotación para mejorar las cinéticas de flotación del cobre y molibdeno e incrementar las recuperaciones de ambos metales.

Sep 9, 2007