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By Pablo Espinoza, Ezequiel Chancan, Luis Loaiza

En este artículo se desarrolla un proceso alternativo al SART, viable para recuperar cobre y zinc por precipitación fraccionada o selectiva. El proceso propuesto es aplicable a soluciones (Barren) producto del proceso Merrill Crowe de precipitación de plata y oro con polvo de zinc, que es recirculada como agua de proceso al circuito de cianuración. En el trabajo se determinan los parámetros para una exitosa precipitación fraccionada de zinc y cobre a partir de una solución cianurada en medio alcalino. Se concluye además que la recirculación de la solución cianurada con menores contenidos de cobre y zinc mejora la recuperación de plata y el rendimiento del proceso de control de cianuros en la solución agotada que constituye el relave final.

Jun 30, 2019

By William J. McDonough

Advanced materials are polymers, metals, and ceramics fabricated as intermaterial compounds, alloys, or composites. The resultant components have higher strength-to-density ratios, greater hardness and wear resistance, and one or more superior thermal, electrical, or optical properties when compared with traditional materials. Advanced materials, the basis for many of today's emerging technologies, offer savings in total energy consumption, improved performance at reasonable cost, and less dependence on imports of strategic and critical mineral resources.

Jan 1, 1992

By Lee T. J

The area, A, under a gamma-ray log that passes through a horizontal bed given by: A = gl/k. Here is the equivalent concentration of U3O8 in the body, l the thickness of the body, and k the calibration factor or sensitivityof the logger. The area is independent of the logging speed or logger time constant.This relationship, together with the first moment about the maximum of the log and its value there suflicient to determine the thickness, position of the centre of the bed from the log maximum and the concentration of U3O8.Numerical results obtained from artificial and field data show that the computed results arc as good as those obtained by methods such as the inverse filter technique and the iterative method. The present method yields results that arc easier to feed into an ore reserve data base.

Jan 1, 1981

By S. Hoskins, S. Chiovelli

"The annual budget for the repair and maintenance of equipment at Syncrude Canada Ltd. is in excess of $450 million. Of this amount, a significant portion can be attributed to the loss of material on various pieces of equipment throughout the operation. In order to effectively battle the different wear and corrosion mechanisms that lead to material loss, it is important to understand how materials behave in the environments in which they are used. Through the work carried out at Syncrude, and work conducted with various external collaborators, significant improvements in both equipment reliability and productivity have been achieved. This paper will review some recent field trials where materials research has demonstrated the potential for significant improvements in equipment run life and reduced maintenance costs. These field trials will demonstrate the need for understanding the interaction between various damage mechanisms and the materials used in different services. The paper will also discuss current areas of focus along with future directions for further work. IntroductionSyncrude Canada Ltd, located in northern Alberta, Canada, operates a mining, extraction, and upgrading facility that removes bitumen from oil sand to produce synthetic crude oil. Oil sand is mined from the orebody using conventional open pit mining techniques. Recently, the mining scheme has changed from a dragline/bucketwheel/conveyor system to a shovel/truck/crusher/hydrotransport operation as depicted in Figure 1. Since the start of production in 1978, the identification, development and application of wear protection has been an ongoing challenge due to the abrasive nature of the oil sands and the massive volumes of materials that are moved. The use of various materials and application processes along with component design modifications has resulted in significant improvements in both productivity and reliability (Adamic et al., 1995; Llewellyn, 1996, 1997; Anderson et al., 1998; Chiovelli et al., 1998).In an effort to continuously improve the operation, Syncrude has been quick to adopt new wear technologies. As seen in Figure 2, since the start of operation, a variety of materials have been used to increase wear performance and ultimately equipment reliability and availability. Although Figure 2 does not show a time axis, the bottom axis may also be used to represent a time progression for the predominate use of these materials at Syncrude. Tungsten carbide metal matrix composite (WC-MMC) overlays are currently the materials of choice for most of Syncrude’s critical production applications. Metal matrix composite overlay technology has potential for significant improvements and Syncrude is actively working with powder consumable manufacturers to advance this technology."

Jan 1, 2004

By S B. Stewart, C J. Restarick

Over a four-hour period of steady plant operation samples were taken at regular intervals frum points within the grinding and flotation circuits. Size fractions of each composite sample were analysed for lead and zinc values and a comparison made of the behaviour of the lead, zinc and gangue minerals, size by size throughout the whole circuit. Analysis of the breakage behaviour using dynamic mathematical models gave the rates of breakage of each size fraction of each main component. Simulated grinding experiments shaved that the main grinding circuit had some reserve capacity. In the lead flotation circuit all lead values between 150 mesh (Tyler) and 5 ¦m had excellent flotation characteristics, and a major proportion had a high rate of flotation which was practically the same for all sizes. Increase in overall lead recovery would require improvement of the flotation behaviour of ultra-fine lead minerals. These were slav floating and were responsible for approximately half the lead losses in the final zinc concentrate and one thiro of the lead losses in the final tails. All sizes of zinc values between 150 mesh and 7 ¦m floated well and the performance of the zinc flotation circuit was mainly limited by the relatively poor flotation of the very fine zinc values. Approximately 60 per cent of the zinc lost to the final tails lay within the -7 ¦m fraction. The overall flotation conditions were conducive to very good selective flotation of the major proportion of the values and limitations in metallurgical performance were mainly due to the properties of the ultra-fines.

Jan 1, 1971

By Miguel Quispe, Miguel Gonzalez

El presente trabajo consiste en presentar la metodología realizada para la mejora de la operación dentro del pad principal con la finalidad de afrontar los problemas presentados por el incremento en finos presentes en el mineral alimentado al PAD. Esta metodología contempla el incremento progresivo del blending de mineral, mejoramiento en la remoción de las celdas, disminución de altura de los lifts desde 8 a 6 metros, incremento en la realización de pruebas metalúrgicas (pruebas granulométricas, de compactación-permeabilidad, lixiviación en columnas), un mejor control de la calidad del % de finos, y una caracterización mineralógica enfocándonos en especial a las arcillas

Sep 29, 2023

By Patrick E. Durnal

A joint venture of Ben C. Gerwick Inc., Sverdrup (now Jacobs) and DMJM (now DMJM Harris) designed the $779 mill seismic upgrade of the Richmond - San Rafael Bridge over the San Pablo Bay in the San Francisco Bay Area and provided construction support to Caltrans. Construction of the marine foundation retrofit was completed by a joint venture of Tudor Saliba/Tidewater/Koch-Skanska and their subcontractors: Pomeroy Precast Construction, AGRA Foundations, Dutra Construction and Vortex Divers. Construction management and inspection was performed by Caltrans with support of various consultants.

Jan 1, 2013

By Pedro Vargas Gálvez

El presente texto señala la metodología de selección del software de mantenimiento respecto a este mismo y a la Planta. Para ello, se detalla las condiciones que deberán considerarse en la Organización de Mantenimiento y la aplicación del Software de Mantenimiento MP2 a una empresa. Asimismo, se presenta el Plan de Implantación, los inconvenientes que se han encontrado así como los resultados obtenidos por la utilización del Software MP2.

May 25, 1998

By E. Amini

"While methods exist to allow the simulation and optimization of existing flotation operations, there is a deficit in the ability to predict the performance of a new ore type pre-processing. A laboratory scale batch flotation testing methodology has been developed to assess the flotation potential of ores (known as the JK Floatability Index or JKFI). Previous work conducted by Alexander and Collins (2008) showed that the test could be used to predict full scale results in base metal ores. In this work, JKFI tests were applied to three different types of ore and one blend from a greenfields gold deposit to show the test applicability to flotation of precious metals. The results from the JKFI test on one ore type were then used to predict the response of all ore types (including the blend). To validate the predicted kinetic parameters, a comprehensive survey was performed on a pilot plant where each of ore types was processed in the circuit. An acceptable agreement was found between the experimental recoveries and predicted recoveries which indicate the potential of this method for use in predicting the flotation response of an ore.INTRODUCTIONOver 100 years, flotation has been considered an efficient method to concentrate different types of sulphide and oxide minerals and coal. Thus, numerous research studies have been undertaken to find an appropriate model to predict the behaviour of particles in flotation circuits (Barnwal et. al., 2006; Bascur and Herbst, 1983; Cecile and Villeneuve, 1991; Deng et. al., 1996; Zheng et. al., 2006). Most methods are based on the ore flotation response in an industrial plant which is expensive and time consuming to characterise. It is difficult to reliably predict flotation response for new types of ores in industrial scale plants.The floatability component modelling (FCM) approach, developed within the Australian Minerals Industry Research Association (AMIRA) P9 project, has been used to derive models of operating flotation plants for the purpose of simulation and optimisation (Alexander and Morrison, 1998; Alexander et. al., 2000; Varadi, 2006). This approach has been applied at a large number of operating sites treating a wide variety of ores. The approach requires metallurgical surveys to be undertaken in conjunction with batch flotation tests and cell characterisation. This allows ore and machine parameters to be derived, which are then used in the P9 Flotation Model. The development of a FCM generally requires a large commitment of resources and time. While there has been significant support of this approach in industry, the FCM approach is limited to ores already being processed (Runge, 2004; Wightman, 2006)."

Jan 1, 2009

By Sergio Samuel Sarmiento Sobrino

Dado que toda actividad minera genera relaves -en tanto son altas concentraciones de químicos y elementos que alteran el medio ambiente- estos deben ser transportados y almacenados en «tanques o pozas de relaves» donde lentamente los contaminantes se vayan decantando en el fondo y se pueda recuperar el agua. En ese sentido, el presente texto señala el manejo de relaves compactados en el depósito de Ramahuaycco, a través de desaguar los tóxicos antes de ser depositados. Así, los relaves filtrados son primero espesados y luego filtrados para el contenido de agua adecuado para su disposición. Por razones de estabilidad, los relaves filtrados requieren ser compactados a través de la desecación de relaves in situ.

Aug 1, 2015

The more than 40,000 mining industry professionals that are expected to attend the National Mining Association’s(NMA) MINExpo International2000 trade show and conference will be treated to the exhibition’s largest display ever. The exhibit is expected to cover more than 60,385 m2(650,000 sq ft) and feature more than 1,300 exhibitors. The event is set for Oct. 9-12, 2000 at the Las Vegas Convention Center in Las Vegas, NV. Richard L. Lawson, NMA’s president and chief executive officer, said, “MINExpo 2000 will showcase everything that mining is proudest of. This is the largest premier mining exposition in the world.” MINExpo is held every four years.

Jan 1, 2000

By Friedrich Brandstetter

Dentro del desarrollo técnico es importante desplazar las construcciones de infraestructura de forma frecuente hacia el subsuelo. Esto requiere el empleo de equipos especiales, métodos, así como de nuevos materiales de construcción con características especiales que faciliten la ejecución de estos proyectos. Así el acero fue reemplazado por resina sintética, generando resultados muy alentadores en la construcción segura en la naturaleza. En ese sentido, el presente texto señala el empleo de estas resinas y su optimización en la economía.

Mar 1, 1979

The New Technology of Enrichment of a Fine Low-Grade Tungsten from Complex Multi-Metallic Ore

Sep 13, 2010

The application of cost updating with the aid of cost indices is reviewed with particular regard to the mining industry. Examples of applicable cost index series are included with values given for the last ten years. The compilation of the indices is discussed with consideration given to the possible sources of error inherent in their application to specific mining cost problems.

Jan 1, 1990

By Tim O’Neil

The search for precious metals opened up the American West. And Nevada was right in the heart of this development. In the mid-19th century, prospectors seeking gold roamed the hills of Nevada and discovered the ComstockLode. The development of this huge silver and gold deposit began in1859 and was responsible for Nevada’s early entry to statehood. Mining was Nevada’s first industry. In more recent years, the Nevada mining industry has led the nation in gold, silver and barite production. Nevada also produces many other minerals. These include aggregates, clays, copper, diatomite, dolomite, gypsum, lime and limestone, lithium and magnesium compounds, perlite, salt and silica. Even today, Nevada’s mining industry continues to be a major economic force in the state. The mining industry has made more than $10 billion in capital investments in Nevada since 1985. And the value of Nevada’s mineral production last year was about $2.7 billion.

Jan 1, 2000

By Carlos Oré Sánchez

La exploración minera desarrollada en el yacimiento de Poderosa- Pataz conlleva un mejor conocimiento de los controles y la metalogenia de la región. En ese sentido, el presente texto señala el uso del ?18O como indicador espacial en el yacimiento aurífero. Los resultados de esta metodología establecen que los segmentos analizados de las vetas que se encuentran al este, corresponden a los niveles superiores del yacimiento. y en contraparte, las porciones dispuestas al oeste, muestran la zona más profunda del distrito.

May 1, 2014

IN this paper an attempt is made to describe the sluicing operations on the tin fields of north-eastern Tasmania. No claim is made to completeness, for much of the ground has already been covered, and nothing is to be gained by needless repetition. On this account some portions of the subject have obviously received but attention in order that others may be rather more fully dealt with; for instance, referring to the accuracy of various methods of valuing alluvial deposits, particulars of efficiencies, and water duties on both overburden and drift; also, the system of recording water distribution, &c. The plans of the tin-streaming shed, sluice and feed race, and overburden tail-race represent types of the most modern design.GEOLOGY. The principal alluvial dcposits being worked at the present time are situated either in the ancient or modern bed of the Ringarooma River or its tributaries. This river flowed in a north-easterly direction, receiving numerous tributaries on either bank...

Jan 1, 1910

By J B. Gemmell, D R. Cooke

Recent mapping at the Kelian epithermal gold deposit in East Kalimantan, Indonesia has delineated intrusive and extrusive-phreatomagmatic breccias, their magmatic roots, and late-stage endogenous domes of a maar-diatreme complex. The Kelian epithermal system is characterised by a wide variety of mineralised and unmineralised breccias, which include tectonic, hydrothermal, phreatic and phreatomagmatic varieties. Phreatomagmatic breccias and associated igneous rocks post-date early stage alteration and mineralisation, and pre-date main stage precious and base-metal mineralisation. This study emphasises the spatial, temporal and genetic links that have been drawn between diatremes and both epithermal and porphyry systems in volcano-plutonic arcs.

Jan 1, 1999

Rehabilitation, reclamation and restoration are all terms used to describe the repair of land after mining. Here, restoration is used to mean restoring the land's original use, capability or productivity. Effective restoration is dependent on good planning before mining commences and must include a clear definition of post-mining objectives. The physical condition of the land within the mining licence was that of an imperfectly drained soil in permanent pasture, supporting a seasonal supply dairying unit. During the mining process, the soil layers were separated, with the topsoil stockpiled separately. As part of the restoration process, the land was recontoured to encourage surface drainage, with topsoil spread evenly over the recontoured tailings. Low grond pressure machinery was used to minimise soil compaction, with light discing and harrowing used to increase water infiltration. A permanent pasture was sown, with weed species controlled by spraying, both before and after pasture establishment.  Soil testing has been used extensively to ensure there were no nutrient deficiencies that good compromise pasture establishment and performance. Controlled grazing practices were used to ensure that the sown pastures became well established.

Jan 1, 1998

By James Weaver

During the past 16 years, the authors have successfully used high-capacity rock anchors installed inside open-ended pipe piles, driven to bedrock, to provide uplift and overturning resistance for various structures including piers, bridges, power plant components and commercial buildings. These systems were ultimately used on the projects due to a combination of high uplift forces or overturning moments on the structures and the relatively poor subsurface conditions present at the sites. Other, foundation systems such as rock-socketed drilled shafts and spin fin piles were considered but were found to be economically prohibitive or not technically feasible.

Jan 1, 2011