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By Mario Samamé Boggio

La ausencia de la enseñanza adecuada en el comportamiento mecánico de materiales y la falta de análisis en los cursos de ingeniería, señalan un problema de neutralidad e integración del concepto de ingenierías en la educación universitaria. En ese sentido, el presente texto describe la importancia de la enseñanza con la realidad del ingeniero, las implicancias de sus especialidades y su rol político como ciudadado que conoce para mejorar la vida humana en el universo.

Mar 1, 1979

By Fanny Herrera, David Reaño, Luis Chahua, Elio Murrugara

El crecimiento del depósito de desmonte Pampa Verde es altamente dependiente de las siguientes restricciones: (1) opciones limitadas para extender lateralmente los contrafuertes existentes; (2) la necesidad de satisfacer tanto la estabilidad estática como la sísmica; (3) la necesidad de seleccionar adecuadamente materiales de alta resistencia para el refuerzo; (4) la importancia de realizar pruebas específicas del material geosintético de refuerzo para caracterizar su interacción con el suelo; y (5) la compleja geometría del sistema en conjunto, particularmente para su estabilidad global. El dique de contención existente fue estabilizado mediante su reforzamiento con geosintéticos, el cual consistió en un relleno de suelo compactado con una talud de 2,1H:1V sobre un muro de suelo estabilizado mecánicamente (MSE o suelo reforzado). La estructura MSE involucra dos muros (superior e inferior) con una banqueta horizontal entre ambos. El muro superior está reforzado con geomallas, mientras que el muro inferior consiste en un sistema Terramesh de gaviones reforzados con geomallas. El enfoque general del diseño consideró el diseño de un talud de suelo reforzado con geosintéticos (TSR) que usaría geomallas de alta capacidad de tracción. Las guías de diseño para el TSR propuesto son las emitidas por la Administración Federal de Carreteras de EE. UU. (FHWA-NHI-10-024). Un aspecto clave a considerar en el diseño propuesto fue la adecuada evaluación de la interfase del suelo contra la geomallama, por lo que se consideró un total de cinco productos de geomalla para su posible uso en la construcción del talud de suelo reforzado con geosintéticos.

Sep 20, 2019

By Oy Leuangthong

The McMurray formation in the Athabasca oil sands deposits of Northern Alberta is part of the world?s second largest proven crude oil reserves. The formation is characterized by stratigraphic layers that correspond to three different depositional environments: Marine, Estuarine and Fluvial facies. Resource estimation for oil sands has traditionally relied on polygonal and inverse distance schemes. These techniques are simple and straightforward in practice, but they do not permit reliable uncertainty assessment. This paper describes the modeling of the McMurray formation using modern geostatistical techniques. Geostatistical modeling should be performed within homogeneous geological facies. The methodology for geostatistical simulation within each of the identified facies involves: (1) assessing the most appropriate stratigraphic transformation for optimisation of the correlation structure, (2) determining representative distributions with declustering and debiasing techniques, (3) modeling spatial continuity of the bitumen grade, fines grade, water saturation and other petrophysical variables, (4) performing estimation and cross validation as checks against simulation results, (5) performing simulation for uncertainty quantification of bitumen and fines grade, and (6) model checking of simulation results against the input data and comparisons against the kriged models. These steps are described in detail. The application of these models for uncertainty quantification in support of resource classification is also discussed.

May 1, 2004

By P. Mark. Hawley

Development of Barrick Gold?s Pierina Gold Mine in north-central Peru requires construction of a waste dump for disposal of non-ore grade materials stripped from the open pit to expose the ore. The waste dump site is located near the open pit in a U-shaped valley that is underlain by thin colluvial and morainal soils with locally thick peats and glaciolacustrine deposits. Bedrock underlying the site consists of variably weathered volcanics. The site is subject to moderately high seasonal rainfall and significant seismicity. The geotechnical quality of the waste rock is highly variable, ranging from low quality, degradable, soil-like materials containing appreciable quantities of silt and clay, to high quality, hard, durable, blocky waste rock. A hybrid dump design concept was developed that requires in-pit segregation of high and low quality waste, and selective placement of materials in the dump to maximize stability and enhance internal and subsurface drainage. The design includes a rock drain beneath the dump along the axis of the valley and a series of connected finger drains. Extensive peripheral diversions and stormwater control measures to inhibit infiltration of precipitation are also included. This paper discusses the unique challenges presented by the site and waste materials, the design methodology and stability analyses, and planned monitoring systems.

May 1, 2002

By José Luis Limaymanta Marcos

En la última Cumbre de Países de América Latina, Unión Europea y el Caribe, realizada en Lima, se evidenció la necesidad de realizar cambios en los países para disminuir la brecha de la desigualdad y se elimine la pobreza -en tanto educación de calidad y excelencia. Para el caso peruano, dicha pobreza radica en las zonas de influencia minera, donde nacen los conflictos sociales. En ese sentido, el presente trabajo describe un modelo de desarrollo solidario que pueda reducir este impacto social a través de una educación de calidad, el cual se sustenta sobre la base de las transferencias de los beneficios que genera la minería tales como: canon, regalías, así como reforzar el crecimiento de los beneficios indirectos tales como los puestos de trabajo colaterales del rubro minero para integrantes de las zonas de influencia minera, el uso, consumo de insumos y servicios de PYMES establecidas en estas áreas y cuyos productos se orientan a las Empresas Mineras.

Sep 14, 2009

By Victoria Frisancho Motta

El proceso de intercambio iónico es una operación de importancia en la hidrometalurgia peruana ya que posibilita el tratamiento de minerales considerados de ley demasiada baja en la actualidad por los métodos convencionales. En ese sentido, no solo es posible las comparaciones favorables en costos con los métodos de precipitación, lixiviación y fundición técnica, sino que también la alta pureza del metal puede ser obtenido por la hidrometalurgia. Por ello, el presente trabajo señala la función de las bacterias como agentes modificadores del orgánico mineral, las cuales migran por los circuitos de orgánico y electrolito de los sistemas de extracción por solventes y electrodeposición, de acuerdo al grado de reacción en la extracción o reextracción de los minerales a tratar.

Nov 20, 1978

By Paul Ruíz

Con el objetivo de aumentar la utilización de la flota de acarreo, la Compañía Minera Antamina implementó el proyecto llamado "Relevo en Caliente" en el año 2022. En el marco de este proyecto, se incorporaron 196 aprendices procedentes de las comunidades cercanas, de los cuales el 41% fueron mujeres. El propósito de esta iniciativa era formarlos como operadores de camión minero

Sep 29, 2023

By Juan Kobashicawa, Bernardo Falcón

En este trabajo se describe el sistema de controles automáticos desarrollados (in house) e implementados en el circuito de molienda de Compañía Minera Antamina, el mismo que abarca molinos SAG, de bolas y los hidrociclones respectivos. Los mecanismos implementados están basados en el control por lógica Fuzzy y las bandas de Bollinger. En el artículo, se indican los criterios empleados para el diseño de los controladores y las variables del proceso, en el caso de indicadores de distancia del centro de masa de la carga respecto al centro del molino de bolas. Finalmente, se informa el impacto positivo logrado con la estabilización del circuito.

Jan 31, 2019

By Pedro Perata

"El siguiente estudio revisa la venta, uso industrial y posicionamiento de la antracita dentro de Lima y sus alrededores. En ese sentido, se busca encontrar posibles consumidores de otros combustibles que pueden convertirse en ancracita. Por ello, el campo doméstico se ofrece como la zona más idónea puesto que ofrece una mayor demanda de kerosene, al tiempo que el precio de venta es barato, que en un mercado libre de competencia y con kerosene a precio mundial, es más factible la posición de la antracita dentro del mercado. Otro posible lugar, lo encontramos en las chimeneas para calefacción, puesto que las briquetas de antracita son superiores a la leña u otro combustible y el costo es similar económicamente. En los usos industriales, se conoce que el consumo total de combustible alcanza 286 mil toneladas de petróleo residual y 46 mil toneladas de petróleo diesel, solo si el precio del petróleo desciende entre 360 y 400 por tonelada, la antracita podría competir. Finalmente, en algunas industrias pequeñas, el gas metanizado y construidode antracita en una planta central, es el preferible al del petróleo."

Jul 20, 1956

By Francisco Tapia

El presente trabajo describe la importancia de la seguridad minera a lo largo del tiempo y cuál es su visión a partir del tercer milenio. Para ello, revisa los costos y pérdidas en la minería peruana -en tanto afecta la imagen de calidad de nuestro producto por los índices de accidentabilidad que guardan, así como plantea una análisis de la efectividad de los programas de seguridad a futuro. En este sentido, el concepto de "seguridad" con visión para el tercer milenio, implica un control predictivo a los "cuasi incidentes", donde se identifique y evalúe los riesgos antes de que se origine la pérdida, así como resalta la función de la ergonomía de los factores humanos en la administración del control de pérdidas.

Oct 6, 1999

Several Approaches to Enhance the Bioleaching of Enargite Some approaches were investigated to enhance the recovery of Cu from enargite by bioleaching with Acidithiobacillus ferrooxidans using the galvanic interaction with pyrite and activated carbon, and with thermophilic bacteria, Acidianus brierleyi. Addition of pyrite initially enhanced Cu leaching by the Galvanic effect, but after that the formation of secondary minerals passivated the surface of enargite in inoculated batches. Activated carbon improved Cu recovery from enargite much better than pyrite, when it is contacted with enargite. Recovery of Cu from enargite has been recorded to at largest 2.4 per cent within 30 days in the presence of activated carbon when mesophilic bacteria were inoculated at 25¦C. The recovery of Cu from enargite was drastically enhanced by inoculation of thermophilic bacteria, Acidianus brierleyi, up to 60 per cent within 40 days at 70¦C and still not leveled off after 40 days unless the formation of Fe(III) precipitates occurred. After 40 days dissolved molar ratio of Cu/As is around 5.2, suggesting that metal-deficient sulfides and/or ferric arsenate might be formed on the surface of enargite.

Sep 13, 2010

By Donald P. Tuchman, Justin R. Patts, Emanuele G. Cauda, Andrew B. Cecala, Elaine N. Rubinstein

Video techniques for monitoring exposure, such as NIOSH’s “Helmet-CAM,” employ both real-time dust monitors and mobile video cameras to assess workers’ respirable dust exposures. Many real-time personally worn dust monitors utilize light scattering sensing elements, which are subject to measurement biases as a function of dust type (size, composition, shape factor) and environmental conditions such as relative humidity. These biased and inaccurate dust measurements impair the monitor’s ability to properly represent actual respirable dust concentrations. In the testing described, instrument mass concentration data was collected using three different types of commonly used commercial off-the-shelf personal dust monitors and compared to a reference standard. This testing was performed in a calm air (Marple) dust chamber in which three units of each make and model (for a total of nine monitors) were used for each test. Equivalency factors (EF, a multiplier to match the Thermo TEOM 1400a reference instrument) ranged between 0.746 and 1.879 across all dusts and environmental conditions tested, and between 0.821 and 1.519 on the ISO test dust.

By Donald P. Tuchman, Justin R. Patts, Emanuele G. Cauda, Andrew B. Cecala, Elaine N. Rubinstein

Video techniques for monitoring exposure, such as NIOSH’s “Helmet-CAM,” employ both real-time dust monitors and mobile video cameras to assess workers’ respirable dust exposures. Many real-time personally worn dust monitors utilize light scattering sensing elements, which are subject to measurement biases as a function of dust type (size, composition, shape factor) and environmental conditions such as relative humidity. These biased and inaccurate dust measurements impair the monitor’s ability to properly represent actual respirable dust concentrations. In the testing described, instrument mass concentration data was collected using three different types of commonly used commercial off-the-shelf personal dust monitors and compared to a reference standard. This testing was performed in a calm air (Marple) dust chamber in which three units of each make and model (for a total of nine monitors) were used for each test. Equivalency factors (EF, a multiplier to match the Thermo TEOM 1400a reference instrument) ranged between 0.746 and 1.879 across all dusts and environmental conditions tested, and between 0.821 and 1.519 on the ISO test dust.

By P Moswate, D Phillpotts, S M. Mantsho, P Strobos

A challenge on many industrial flotation circuits is controlling concentrate mineral grades using measurements that are provided infrequently. The mineral grades in concentrate streams are a critical performance indicator in any industrial flotation circuit. Failure to achieve concentrate mineral grade targets has significant financial consequences on a flotation operation. A violation of gangue mineral grade limits by the concentrator may also result in significant penalties.Online grade analysers which can provide reliable real time grade measurements are essential for effective grade optimisation. The Blue Cube MQi analyser (by Blue Cube Systems) has recently come to prominence for its ability to rapidly determine mineral concentrate grades online and has the benefit of operating in-stream. This has provided excellent insight into the actual process dynamics in the flotation circuit, and hence enabled real-time control and optimisation of concentrate mineral grades.MintekÆs Measurement and Control division, specialising in advanced control solutions for mineral and metallurgical industries, has had the opportunity to link the FloatStar Grade-Recovery Optimiser to the measurements provided by the Blue Cube system at the BCL nickel concentrator plant in Botswana. The project focused on stabilising the final concentrate grade while ensuring the final tailings are minimised, resulting in an improved nickel recovery. This site already had the FloatStar Grade-Recovery Optimiser for several years, but the original grade measurement device was unreliable and ultimately failed. The system was reactivated once the Blue Cube system was installed, replacing the old analyser. The positive results show the advantages of combining reliable real time measurements with an advanced process control system.CITATION:Mantsho, S M, Moswate, P, Strobos, P and Phillpotts, D, 2013. The implementation of floatstar grade-recovery optimisation control solutions using Blue Cube Online grade analysers on industrial flotation circuits, in Proceedings MetPlant 2013 , pp 575-582 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Pedro Alejandro Samané Tuni

El presente texto describe las soluciones que disponen los geólogos e ingenieros para actuar de forma adecuada en la planificación, diseño y construcción de los proyectos, así como se muestran los errores de concepto que todavía persisten cuando se usan las clasificaciones geomecánicas.

May 1, 2013

Research and Application of Vertical Screw Stirred Mill

Sep 13, 2010

By José Manzaneda Cabala

El presente texto señala conceptos básicos sobre la activación y depresión de sulfuros de plomo y hierro, la nueva aplicación del criterio Flash y el uso de la plantilla de diseño experimental para establecer si un nuevo depresor orgánico puede ser la alternativa de reemplazo del depresor cianuro de sodio en flotación. Para el estudio se realizó un diseño factorial fraccionado para estudiar cuatro variables. La plantilla permitió evaluar sulfato de zinc, cianuro de sodio, grado de molienda y un nuevo depresor orgánico donde se encontró que el reactivo RA-CN300 es un depresor de sulfuros que reduciría el consumo de cianuro de sodio y contenido de cianuro en total en el agua de la relavera.

Nov 1, 2014

By Neil White

South Africa (SA), a country in which all three commercially important asbestos minerals have been mined and milled, has retained proven cases of mesothelioma linked with environmental exposure to asbestos. This study illustrates the importance of fiber type in the occurrence of environmental mesothelioma. Four studies have reviewed the source of occupational or environmental asbestos exposure in 504 histologically proven cases of mesothelioma in South Africa. One hundred and eighteen cases (23%) were thought to be related to environmental exposure to asbestos. In the vast majority of these cases, exposure was linked to crocidolite mining activities in the Northern Cape Province. Two cases were thought to have occurred in relation to amosite and Transvaal crocidolite exposure in the Limpopo Province. In the balance of cases there was some uncertainty. No cases were reported with exposure to South African chrysotile. Consequently, in the vast majority of cases of mesothelioma, environmental exposure to asbestos occurred in the Northern Cape Province, in proximity to mines, mills and dumps where crocidolite was processed. Crocidolite appears to be far more mesotheliomagenic than amosite, and chrysotile has not been implicated in the disease. This is true for both occupationally and environmentally exposed individuals. ©2007 Elsevier Inc. All rights reserved. Keywords: Crocidolite; Mesothelioma; Chrysotile; Amosite; South Africa

Jan 1, 2007

By Chris Tattersall, Tomyuki Kudo, Peter Raleigh, Nestor Garavelli, Steve Redmond, Michael J. Lehnen

Twin bore running tunnels driven approximately 4,500 route feet by a Mitsubishi Heavy Industries (MHI) EPB Tunnel Boring Machine link the West Portal and East Portal on this complex Light Rail Project. One third along the way, the TBM arrives at the Beacon Hill Station which is the deepest underground “binocular” station of its kind in North America and then “walks-across” the station to be re-launched on the other side to complete the drive. This paper discusses briefly the layout and design considerations but then focuses more deeply on the approach by the Contractor to drive and supply the tunnel. The paper addresses the approach used to launch, re-launch and recover the TBM and touches briefly on muck volume control and monitoring plus settlement monitoring and the performance achieved. Also of interest is a unique solution to a difficult launch situation involving a secant pile tieback wall designed with several rows of double I-beam steel walers spanning the eye at the West Portal under the I-5 freeway.

Jan 1, 2007

By Edward A. Metz, R. Larry Grayson, Douglas F. Scott

We describe inconsistencies in disease and illness reporting in U.S. mining, identify under-reporting of disease and illness in U.S. mining, and summarize selected disease and illness in U.S. mining from 1983 through 2001. Methods: We summarized information on mining-related disease and illness data for the years 1983-2001 from the Mining Safety and Health Administration database (MSHA). Results: Discrepancies exist in types of information collected by the Centers for Disease and Control, the National Institute for Occupational Safety and Health, and the Mining Safety and Health Admin¬istration database. Several factors, including a worker's fear of losing his or her job, health insurance, or other job-related benefits contribute to under-reporting of disease and illness information in the US mining industry. Conclusions: Since 1997, both number of workers employed in mining and disease and illness rates have decreased; however, the highest disease and illness rates in mining continue to be coal worker's pneumoconiosis and hearing loss.