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By A. Mcdonald, F. W. Breaks, T. F. Morris, S. A. Averill, D. C. Crabtree

Gahnite, a zinc-bearing spinel, is a resistate mineral that may be used as an indicator mineral of polymetallic deposits in high-grade metamorphic terrain. The Ontario Geological Survey recently completed sur?cial mapping and sampling programs in the Separation Lake area of north-western Ontario and Kinniwabi Lake area of northeastern Ontario in which gahnite was recovered from samples of sur?cial sediments. Ternary plots of the composition (ZnO, MgO, FeO[t]) of gahnite recovered from these sur?cial studies reveal three distinct groups: Group 1 is characterized by low (< 1 wt%) MgO values; Group 2 by higher (>1 wt%) MgO values; and Group 3 by higher FeO(t)values than Groups 1 and 2. The composition of in situ gahnite recovered from volcanogenic massive sul?de mineralization, Zn-rich Sedex-type mineralization and peraluminous rare-element mineralized granite and pegmatite also was determined. The composition of the gahnite obtained from sur?cial samples was compared with that of in situ material. Gahnite from the peraluminous rare-element granite and pegmatite overlapped very well with sur?cial gahnite of Group 1. Gahnite from volcanogenic massive sul?de mineralization and Sedex-type mineralization overlapped well with sur?cial gahnite of Group 2. These results suggest that determination of gahnite composition in indi-cator mineral surveys may be useful in exploration programs when assessing the mineral potential of a region.

Jan 1, 1997

By Ian E. Efford

The paper gives an assessment of Canada&apos;s energy supply-and-demand position, the current situation and projections into the future, as well as a review of some alternative energy futures for Canada. The main elements of Canada&apos;s energy strategy for the period 1977-1990, with particular reference to the role of energy conservation, are discussed, leading in to the development of the national energy conservation program.

Jan 1, 1977

By E. C. Lane

[This Is the ninth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the United States Department of the interior. The first report gave data on motor gasoline sold during the winter of 1935-36.3/ The Present report presents analytical data for 2,033 samples, representing the products of approximately 80 companies, which, as in previous surveys, include both large and small suppliers. In addition, the Pacific coast is represented by data that were average by the Pacific Coast Technical Group before &apos;being submitted and are published exactly as they were received. As in previous surveys, the data are divided into the three groups of samples of regular-price, premium-price, and third-grade gasolines, and each group has been averaged separately. The cumber of samples, items, and brands comprising each group, exclusive of those of the Pacific coast, arc as follows: Regular price, 1,066 samples, 208 items, and 49 brands; premium price, 575 tamales, 154 items, and 38 brands; third-grade gasoline, 7;4 samples, 150 items, and 53 brands. The meanings of these terms as used in the surveys tar as follows: Sample: The individual supply of gasoline obtained at the filling station and analysed in the laboratory.]

Jan 1, 1940

By Ed McConaghy, P. LaRochelle

The Ambatovy Nickel Project comprises the development of mine, hydrometallurgical processing facilities and necessary infrastructure in Madagascar, positioning Ambatovy as one of the world’s largest producers of nickel and cobalt from lateritic ore. SNC-Lavalin successfully provided comprehensive Engineering, Procurement, Construction Management (EPCM) services for this major capital project which, apart from its sheer size, scope, and engineering design, represented significant location, infrastructure, labour, environmental and climatic challenges. Today, the project has reached 90% of its nameplate capacity and is in its final performance optimization stage. This paper will discuss the significant project management effort that was required to successfully address the complexity of this major project. It will cover the main project management control systems and the engineering tools and processes used during the detail engineering, procurement, and construction phases to achieve optimum project execution.

Jan 1, 2015

By Fernando Zúñiga y Rivero

La petrofísica es una ciencia que estudia las relaciones entre la textura de la roca y sus propiedades físicas, de flujo y las propiedades radioactivas. Dada esta premisa, el objetivo del texto refiere su etimología, los componentes del sistema de fluído (rocas, fluídos y presiones), los requisitos fundamentales de las rocas, su reservorio, clasificación, propiedades, características de los reservorios, textura, componentes texturales, los fluidos, agua de formación, petróleo, presión, efecto, distribución, aplicaciones del petróleo y los métodos de recuperación secundaria y terciaria.

Aug 20, 1965

By Juan Asalgado

The JORC and NI43-101 codes impose that mineralized material has a reasonable prospect of economical extraction to be classified as Mineral Resource. For deposits close to surface and amenable to open pit mining, it is easy to show reasonable prospect of economic extraction running a Lerch-Grossman optimization. The Lerch-Grossman pit provides a transparent and repeatable way of separating the Mineral Resource (within the pit) from the remainder of the mineral inventory (outside the pit). Deposits amenable to underground mining are more challenging because of the variety of the underground methods. AMEC developed a stand-alone software package that outlines the material which has reasonable prospect of economic extraction for open stoping, block caving, sublevel caving and room and pillar. The software takes a block model file in ASCII and exports a 3D surface outlining the part of the mineralization that has a reasonable prospect of economic extraction, and which the Qualified Person can smooth out manually if required.

Oct 1, 2009

By Marcos Valdéz Córdova

El presente estudio señala el proceso de mineralización en el domo de Yauli a través de una revisión en el comportamiento de dominios estratigráficos, estructurales, intrusivos, metamórficos y distintos minerales de alteración hidrotermal. Asimismo se describe la geología, su estructura, la alteración de los intrusivos, la alteración de los silicatos metamórficos, la alteración de los mármoles y calizas dolimíticas, cuerpos, mantos y las vetas de reemplazamiento.

Nov 20, 1978

By D. F. Zhang, X. Q. Jiang, N. Tahreen, D. L. Chen, F. S. Pan, D. Y. Li

Alloying with rare-earth elements has been proven to be an important tool for magnesium to achieve superior properties via texture randomization. The role of yttrium in texture weakening and the link between texture and formability are fairly well known. Since annealing is a vital part of metal processing which could significantly contribute to ductility, it is important to ascertain the impact of annealing in terms of texture change. Also, an understanding about texture development during pre- and post-deformation annealing is essential to improve the industrial deformation processing as texture is closely related to formability. While there is independent information in the literature regarding the effect of rare-earth addition and heat treatment on the texture formation, no systematic studies have been reported on the collective impact of yttrium addition, annealing and deformation on texture evolution. The present study was, therefore, aimed to identify the inter-relationship among texture evolution, yttrium content, heat treatment and deformation behavior in an extruded Mg-Zn-Mn-Y alloy. Annealing at 450°C for 1 hour and uniaxial compression tests at a certain amount of deformation were performed. The deformed and annealed samples were then subjected to annealing and compression test, respectively, followed by texture measurements. It was observed that yttrium addition effectively weakened the crystallographic texture in all conditions, which was evident from the changes in the microstructures and textures.

Jan 1, 2015

By S. Swaroopa

Copper-chromium mixed oxides are widely used as catalyst for organic chemicals industry, NOx and CO oxidation, solid propellant etc. In the present investigation, one such spent Cu-Cr catalyst has been tested for recovering copper and chromium values through hydrometallurgical route. The spent catalyst used in this study contains about 42% Cu and 36% Cr. Phase analysis through XRD indicates that major phases are copper chromium oxide (CuCrO2) and copper chromate (CuCr2O4) while minor phase is copper oxide (Cu64O). SEM images show that high energy ball milling changes surface morphology significantly ? more regular shaped grains in unmilled samples changed to fine agglomerates. Surface area also changes significantly due to milling. Preliminary leaching experiments with NH3 and H2SO4 media using unmilled samples indicate that both the media are suitable for selective extraction of copper. About 55% copper recovery is achieved in 2 h using 1.2 M NH3 + 0.2M (NH4)2SO4 solution at 100°C. Increasing NH3 concentration or temperature does not improve the recovery significantly. Under the above conditions chromium, dissolution is insignificant (max. 2.24%). XRD analysis of the residue indicates that copper chromate fraction (CuCr2O4), which is a spinel structure, remains mostly intact. In sulphuric acid media at ambient temperature, 47% copper recovery is achieved with 7.5% (v/v) H2SO4 and maximum of 57% with the increase in acid concentration to 20%. However, 67% recovery is achieved by increasing the leaching temperature to 150°C. High energy ball milled samples show improved leaching efficiency. Under the leaching conditions of 7% H2SO4 (v/v), 2% pulp density, 80°C an unmilled sample yields 47% Cu recovery whereas 3h and 5h milled samples yield 65% and 90% Cu recovery respectively in 2h leaching time. Influence of temperature is also more pronounced in milled sample leaching in comparison to unmilled sample. Water leaching of alkali (NaOH) roasted milled sample carried out at 750°C for 2 h with 100% NaOH (w/w) resulted in 80% Cr recovery as compared to 37% Cr recovery using unmilled sample under the same conditions. Keywords: spent catalyst, copper, chromium, leaching, mechanical activation, roasting

Sep 1, 2012

By Quenton Johnson, W. A. Gough, David Carr

"This paper describes the application of the BrainWave Model Predictive Controller (MPC) and Advanced Control Expert (ACE) Advanced Supervisory Control System on the SAG Mill, Ball Mill, and Rougher Flotation cells for a new gold processing line at the Oceana Gold - Haile Gold mine in Kershaw, South Carolina. For this project, ANDRITZ supplied the control system design and programming, operator-training simulator and advanced control. The advanced control was tested against the IDEAS™ dynamic simulator, and commissioned during the startup of the processing plant to help achieve target production as quickly as possible. Operators were able to run the equipment in a consistent and optimized manner from an early stage of the plant operation, increasing efficiency and profitability. MPC is able to reduce process variability beyond the best performance that can be obtained with conventional Proportional Integral Derivative (PID) control methods. MPC is able to optimize the control of processes that exhibit an integrating type response in combination with transport delays or variable interaction, which are characteristic of many gold processes including SAG mill weight control and Flotation cell froth level control. The experience and benefits of applying MPC during the startup of a new gold processing plant are presented in this paper.INTRODUCTION Mineral processing operations present many challenges for automatic process control due to variations in unmeasured ore properties, material transport delays, and non-linear response characteristics. Advanced process control technologies such as expert systems and multi-variable model predictive controllers are often used to improve the control of these processes to increase productivity and recovery efficiency. Typically these systems are applied after the mine has been in operation for a period of time. For this project, a complete dynamic process simulator was developed using the IDEAS platform for the purpose of training operators before the plant was constructed. Operators were able to become familiar with the process and the control system in order to become proficient in the use of the controls before the plant was ready to start. They were able to practice abnormal condition management including startup and shutdown of the process using the simulator and develop complete Standard Operating Procedures (SOPs) for these situations. The simulator was also used to test the control system functionality and operator Human Machine Interface (HMI) configuration to reduce errors and improve the performance of the control system during plant start-up."

Jan 1, 2017

By Agustín Arias

El presente artículo describe brevemente la historia, métodos de explotación, mecanización, energía eléctrica, las plantas de preconcentración y flotación y el consumo de reactivos de la compañía minera Milpo.

Nov 1, 1954

By B. Wasmund, M. Y. Solar, I. Candy

The nickel laterite industry is divided into two camps when it comes to the grade of the ferronickels produced. One group, led by Falcondo and Cerro Matoso, markets high-grade ferronickels in the range of 35 to 40% nickel, while another group, led by SLN and the Japanese smelters, favour lower grades in the range of 20 to 25%. Because the ores processed by these smelters vary widely in terms of nickel content and iron to nickel ratios, it is probably more accurate to classify these smelters in terms of their iron recovery: Falcondo and Cerro Matoso smelt at lower reduction potentials and thus recover only 15 to 30% of the iron in their ores, while SLN and the Japanese smelters are very reducing and recover 45 to 65% of their iron. Low reductions generally imply higher slag losses and lower nickel recoveries, but also lower power and reductant requirements; higher reductions, the reverse. The question is, therefore, whether an economically optimum ferronickel grade exists for processing any given ore. This paper proposes a methodology for determining this optimum grade and concludes that nickel laterite smelters should favour low reductions and production of high-grade ferronickels.

Jan 1, 2008

By Michael J. Pazuchanics

This report documents the current status of the U.S. Bureau of Mines ongoing investigation of the use of adaptive signal discrimination (ASD) systems to distinguish between cutting coal and cutting rock. Cutting-tool forces and vibrations were measured in the laboratory using both conical bits and roller cutters in a linear-cutting apparatus for several material samples and two cutting directions. A number of ASD systems consisting of one or more signal classifiers were trained and tested to study how data window size, type of signal feature, and combining (polling) of classifier results influence system performance. The results show that ASD system recognition rates can be improved by increasing data window size, removing air-cutting portions from the signal data, overlapping data windows, and combining (fusing) information at various levels of ASD system operation.

Jan 1, 2010

By Marcos Meyer Machado

O presente trabalho compreende um estudo sobre os processos de moagem e tratamento térmico de pelotas no que tange as implicações microestruturais de minério de ferro no controle operacional e redução de consumos de energias térmica e elétrica de uma planta de pelotização. As características físicas, microestruturais e mineralógicas foram determinadas para os produtos de minério de ferro, para matriz de experimentos (misturas) e para as pelotas tratadas com auxílio de um microscópio óptico, um eletrônico e um EBSD. Os resultados permitiram confirmar a relação entre as composições morfológicas com a elevação de produção da moagem (14,1%) e redução do consumo de energia elétrica (12,0%). O controle do perfil térmico de endurecimento foi relacionado com as condições de sinterização (grau de maturação) das pelotas submetidas e as fases microestruturais identificadas. Foi evidenciada relação inversa entre o teor de magnetita na mistura com o consumo de energia térmica. Os resultados de resistência à compressão também sugerem uma relação inversa com os teores de fayalita e magnetita não oxidada, porosidade e grau de maturação. Adicionalmente, os resultados proporcionaram ajustes industriais que confirmaram essa relação com a redução da energia térmica aplicada para produção (10,7%).

Oct 30, 2017

By Andrés Recalde

Dado que el riesgo social se ha convertido en uno de los principales factores de éxito o fracaso para un proyecto minero, las familias, comunidades y gobiernos locales en la zona de influencia se constituyen en actores primordiales de un proceso de relacionamiento y acuerdos que debe contribuir al mutuo beneficio. El Modelo o Acuerdo de impacto beneficio (AIB) es una propuesta metodológica desarrollada en Canadá desde 1970, que busca generar consenso entre la empresa minera y las comunidades impactadas social y económicamente por un nuevo proyecto, mediante la firma de un contrato en los que se enumeran los impactos y las medidas de mitigación que se efectuarán en contraprestación para evitar el daño. Los Acuerdos de impacto beneficio permiten guiar el relacionamiento entre las partes, controlar expectativas y mitigar el impacto social. La firma de una AIB es el inicio de la licencia social para operar (LSO), lo que la convierte en un activo intangible del proyecto.

Sep 30, 2017

By A. Galaitsis

This report summarizes part of the work performed under the USBM Contract No H0155113, "Noise Abatement of Continuous Mining Machines." It describes the noise source diagnosis of a Jeffrey 120M conveyor and the evaluation of several treatments all conducted in a test facility aboveground. The conveyor noise at the operator&apos;s position was gradually reduced from 101.5 to 93 dBA using damping, vibration isolation, sound barriers and smoother discontinuities. The underground performance of the selected treatments will be addressed in Volume II of the report.

Jan 1, 1979

By Derek J. Fray

"A need exists for fast and accurate analysis of species in various phases at elevated temperatures. Although modern analytical techniques are very efficient, the equipment is usually situated some distance from the industrial operation and time is spent taking the sample and sending it to the analytical facility. Several minutes can easily lapse and, during this time, heat must be supplied in order to keep the system molten and, if the composition is changing rapidly due to a refining process or reaction with the environment, the information may only be of retrospective use. Perhaps more important reasons for the use of on-line sensors are that instantaneous analysis gives better control, process optimisation and the minimisation of energy losses and pollution. To date oxygen has been the only element which is measured widely using solid electrolytes. However, the analysis of many more elements is required and possible electrolytes for other species are discussed. For some elements, ~here is no suitable conducting electrolyte and, therefore, a different approach is adopted where the electrolyte, in which one species is mobile, comes to equilibrium with another species. IntroductionThere is an ever increasing demand for the development of sensors for on-line measurements in most areas of technology and, in particular, metal processing. This is especially relevant in situations where greater control can be achieved by monitoring the chemical composition of the melt during processing and where a minor constituent in the melt can have a major effect on the properties of the finished alloy. Although modern analytical techniques are fast and reliable, the equipment due to its complexity, is frequently situated away from the process area and valuable time may be spent in sampling and transportation. During this period, heat may have to be supplied to prevent solidification and the refining reactions may be continuing, and, therefore, the analytical information may not be of direct use."

Jan 1, 1988

By R. Patterson

Tracer gas sampling methods are useful for monitoring ventilation systems, especially in remote or inaccessible areas, and can be utilized for analysis of the ventilation system immediately following a mine emergency. However, the success of this technique is largely dependent on the accuracy of release and sampling methods. Analysis of sampling methods is crucial for rapid response and dependable results during emergencies. For the purpose of this study, four well-accepted sampling techniques currently used in the mining industry were compared using solid-phase microextraction (SPMe) fibers with sulfur hexafluoride (SF6), an industry standard, as the tracer gas. Current sample collection techniques include plastic syringes, glass syringes, Tedlar bags and vacutainers. SPMe fibers are used in a variety of industries, from forensics to environmental sampling, and are a solventless method of sampling analytes. To analyze these sampling methods, samples were taken from a 0.01 % standard mixture of SF6 and nitrogen and analyzed using electron capture gas chromatography. A relative standard error of less than 10% validated results to compare the accuracy of various methods. The technical and practical issues surrounding each sampling method were also observed and discussed.

Jan 1, 2011

By J. P. Harrison, M. Grenon

"This paper summarizes the results of numerical studies on drift stability in moderately jointed rock masses. It investigates the relative pertinence of geomechanical factors such as joint orientation, spacing and stress regime. This is undertaken using a distinct element model and a series of parametric studies. IntroductionIn evaluating the stability of drifts in jointed rock, it is often necessary to compromise by employing models that capture the complexity of the rock mass, but which are still simple enough to allow for their routine implementation. The distinct element method can arguably provide an eloquent method to accomplish this. This paper explores the applicability of the method by means of a parametric study aiming to identify the dominant factors that influence the stability of drifts in moderately jointed rock. To this end a commercially available 2D distinct element numerical model was used. A series of techniques are presented in an effort to quantify the results of any instability predicted by the model.This paper also demonstrates a case study where a 3D joint network model was integrated into the distinct analysis software package. The advantages, as well as the current limitations of this approach, are discussed."

Jan 1, 2001

By Grant R. Brown

The report provides guidance for determining those environmental impacts associated with the surface mining of steeply pitching coal seams. In addition to the environmental impacts, four additional issues are addressed, namely (1) Time and motion studies of those coal mining systems employed in mining seams which pitch in excess of 250, (2) Assessment of those mining techniques, (3) Development of rationale for the mining methods employed, (4) Identification of the reclamation practices and determine whether these practices were in compliance with appropriate Federal and State regulations. Five surface mines located in three geologically distinct basins of the United States were analyzed during the period of August through November 1979. The three basins include the Hanna Basin of Wyoming, the North Park Basin of Colorado and the Southern Anthracite Field of Pennsylvania.

Jan 1, 1980