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By Edward Rybinski, Serkan Dikmen, Walter Valery, Jorge Ghersi, Roberto Valle, Alex Jankovic, Javier Linares, Frank Davila

Compañía Minera Antamina is a polymetallic mining complex that produces copper and zinc concentrates as primary products and molybdenum and lead/bismuth/silver concentrates as by-products. In 2007, Metso Process Technology and Innovation (PTI) was contracted to increase SAG mill throughput by integrating and optimising blast fragmentation, crushing and grinding for the harder M4/M4A (CuZn) ores. Following the implementation of recommendations provided by Metso PTI, the SAG mill throughput increased from 2750tph to reach an average of 3600tph for the remainder of 2007. Due to continued application of mine to mill integration and optimisation philosophy, by 2010, the concentrator consistently exceeded the target of 4400tph while processing harder CuZn ores.

Jan 1, 2012

By T. G. Joseph, M. Welz

ABSTRACT: Joseph (2002) introduced passive seismic monitoring to measure mining equipment performance. This paper evaluates the potential of passive seismic monitoring to correlate mining equipment operation with oil sands surface response, with a mining hauler as the seismic source. When applied to moving haulers, this action–reaction approach is complex. Vibrations from on-board equipment, such as pumps and tires, dirty the signal with noise. To facilitate any correlation, the signal must be cleaned up. Existing geophysical analytical techniques were manipulated to evaluate the noise problem and to filter sufficiently to permit an evaluation of whether a mining equipment action–ground response relationships in fact discernable.

Jan 1, 2011

By John Eggert, Paul Benford

"Since 1982, Placer Dome Inc. -Dome Mine has steadily increased mill throughput. Tonnage has increased from a nominal design capacity of 3000 short tons per day, attained in 1985, to 4130 stpd by the end of 1992. Many minor and major circuit adjustments were tried to maximize tonnage.Having utilized most conventional means of increasing tonnage, further increases required a newer approach. This paper discusses the Dome experience in the development and implementation of an expert system.The Comdale/C system was chosen for a controlled trial. The criteria for acceptance were: increased tonnage had to be sufficient to pay for the system; the increase had to be visibly sustainable and the mill operators had to be willing to accept the system.The criteria for purchase were met during the trial and the system was purchased. The system continues to perform well. The tonnage throughput increase has been sustained while operator acceptance remains high.IntroductionPlacer Dome Inc. -Dome Mine is Canada's oldest operating gold mine. The mine was among the first established in the Porcupine camp in what is now Timmins, Ontario. The City of Timmins is located approximately 500 miles or 800 kilometres north of Toronto. Figure 1 shows a map of the province of Ontario and the mine location.In 1912, milling began at a rate of 350 short tons per day. With two minor exceptions, milling has been continuous since this time. The first of these shut downs was in 1918 during the first world war. The war created labour shortages which forced the mine to stop production for more than a year. The second was in 1930 when fire destroyed the mill."

Jan 1, 1994

By W. F. Scott, K. L. Somerville

"This paper outlines the development and inplementation of functional training at the Thompson Mine of Inco Metals Company, Manitoba Division. This training is an extension of similar methods implemented throughout the company to meet safety and health and productivity objectives. It consists of the orientation to the mine, induction in the basic mining skills, and specific training in drilling and other skills in the mine. Initial results indicated a positive effect on the safety performance and proficiency of the mine workforce.IntroductionThe primary mining method at the Thompson Mine is mechanized cut and fill, with secondary recovery of pillars by undercut and fill . These methods require a workforce of about 900 hourly operating employees to obtain capacity production of 6500 tons of ore per day.Historically, turnover of mine employees has been high and large numbers of new recruits are introduced to the mine every year. These men are recruited primarily in Manitoba, but also from distant areas of Canada; most of the se people have no previous mining experience.Training has always been an important component of mine operations. Mine supervisors and experienced miners have committed an appreciable amount of time and effort to training these new recruits. As well, training efforts have been directed toward upgrading the skills of experienced workers.Recently, a growing awareness of the significance of this training effort and its impact on accident frequency, productivity, turnover and other important parameters of the mine operation has led to a review of training methods. The training program described in this paper has resulted from this review."

Jan 1, 1981

By Ron Doucet

Industry today is now more than ever dependent on its assets and on the standard of maintenance. Changes in technology, environmental regulations, a continually improving focus on safety and global competitiveness has made maintenance a key activity in sustaining safe, financially viable and environmentally integral operations. Maintenance used to be looked upon as a cost centre with a sole focus of fixing equipment to attain high availability. Maintenance today affects all aspects of the business: safety, environmental integrity, energy efficiency, productivity, costs, and product quality. These new demands on the function of maintenance requires us to think vastly differently about what maintenance is all about, even to the point of contradicting old beliefs. In the following paragraphs we will examine some of the changed thinking that has evolved over the last 50 years. These new concepts will lay the foundation for the implementation of 21st century best practice maintenance.

May 1, 2003

By Miguel A. Cuba

Resource models are generally constructed using data of different types and/or from different sources. A common issue is the consistency of scale in the information that often leads to a requirement to composite the data prior to model construction. For the purposes of mine planning, development and/or resource assessment, this model may then be upscaled to a relevant selective mining unit. It is well established that the geostatistical parameters for resource model construction is scale dependent. In particular, the volume variance of integrating these various scales has a direct impact on the variogram that should be used in model construction and/or the assessment of volume variance relations as it affects resource estimation. The scaling laws are a set of guidelines that detail how the variogram should change as a result of a change in the volume; these laws are empirically derived and involve some simplifying assumptions, not the least of which is an assumption of shape invariance in the variogram structure. An alternative approach was proposed to directly upscale the variogram via numerical integration, which demonstrates that the assumption of shape invariance is not required and we can directly access the new variogram shape given any volume of interest. This paper compares these two different approaches to variogram upscaling by considering two applications: the first corresponds to a 2D synthetic case and the second looks at a 3D case with data from a porphyry copper deposit. The simulation studies in these cases show that the direct upscaling approach performs better than the scaling laws in fitting the average experimental variogram values at any block size. This is based on a mean absolute error criterion. Moreover, it is also shown that with an increase in the block size, direct variogram upscaling significantly outperforms the scaling laws approach.

Oct 1, 2009

By P. B. Marchant

"Based on laboratory and pilot scale continuous biooxidation of complex sulphide concentrates, commercial processing design and scaleup considerations are discussed. Capital and operating cost estimates for commercial biohydrometallurgical operations are summarized and potential applications of biotechnology are discussed. Biooxidation as an oxidative pretreatment alternative to enhance precious metals extraction from refractory sulphide concentrates in stirred tank reactors has received considerable attention recently due mainly to advances in the practical applicability of the process. Biooxidation of sulphides is certainly not a new process, however, application and control in large scale hydrometallurgical operations to treat refractory sulphides remains conceptual and the limited data available is restricted to relatively small laboratory and pilot scale operations. It is the intent of this paper to indicate scaleup and plant scale process design considerations for commercial bioleach circuits, based on recent operating experiences with laboratory and pilot scale continuous bioleach systems. An indication of the expected range of applications will be presented parameters for optimization will be discussed."

Jan 1, 1986

Adaptive processing is often related to the mineral composition of the mining block currently processed. The portions of waste, ore and secondary product minerals considered are always positive and typically sum to 100% (i.e. a composition). A typical solution to predict block averages of spatially dependent quantities would be block kriging. However, kriging is based on spatial correlations and it has been repeatedly shown that correlations of compositional data are spurious and blurred by the constant sum constraint. Aitchison (1982) proposed a general solution for compositional problems, based on transforming the compositional data to a set of logarithms of ratios of components, and analysing the transformed scores. The transform is chosen to be invertible to ensure that no information is lost in the process. This methodology avoids spurious correlation problems and ensures coherence between results obtained with different subcompositions. Pawlowsky-Glahn and Olea (2004) adapted the approach for point-support geostatistics, allowing the prediction of point compositions from spatially neighbouring data, without the artefacts induced by standard multivariate cokriging. Unfortunately upscaling the results of this approach with block cokriging is not straightforward, because of the nonlinearity of logratio transforms. Furthermore, we have to consider those nonlinearities created by the dependence on the block composition of extraction efficiency and processing costs of the possible processing choices. This paper proposes a solution for predicting the conditional expectations of the benefit of processing the block with each processing choice using geostatistical simulations of the local values of the composition and the resulting block integrals. The computation for a large number of blocks can be done efficiently using Cholesky decomposition. The approach also allows the calculation of prediction errors for expected compositions and expected benefit at almost no additional computational cost. Such compositional approach is necessary, for example when processing choices depend on proportions of certain minerals after other components have been removed; or if processing alters the composition in a multiplicative way, by partially removing a portion of some components.

Aug 1, 2013

By Robert B. Parsons

"Canadian investment abroad has been the focus of considerable attention in recent years. Canadian mining companies have been heavy investors in Latin America and are taking a hard look at Central Asia and the Pacific Rim. This international flow of capital is not one-way however. Foreign mining companies continue to make substantial investments in Canada's mining industry. This month. Tax Notes addresses some of the main Canadian income tax implications of foreign investment in Canada.Foreign Investment in CanadaThere are two basic forms of foreign investment in a Canadian company: share capital and debt. The following comments deal with each of these investments separately. It is appreciated that the relevant tax legislation is, as always, quite complex, and that the notes that follow are intended only to serve as a guide. This article should not be relied on as a substitute for professional advice."

Jan 1, 1994

By V. Ogarlaci

Over 90% of the Romania's lignite reserve is located in the region of Oltenia, which is why this area is given special attention in the country's coal resources. Because the lignite deposit of Oltenia is comprised of 1-8 exploitable coal layers, their capitalizing calls for urgent arrangements to ensure rational exploitation under conditions of total safety, minimum losses and efficiency. The technology used the coal pits of North-Western Oltenia is the technology of excavation, transport and dumping in a continuous flow by using the complexes of excavation, transport and high-capacity dumping. The theme of this paper is of particular importance because the rhythmic operation in complete safety, is necessary both for sizing and keeping within the bounds of acceptable values, throughout the process of excavation of the geometric elements of the coal faces, marked by: the height of benches, slope angle and width of berms. Geometric dimensions of the benches of the open pits, the height of benches, slope angle and width of berms shall be calculated and shall be based on: the massif structure that forms the benches; physical-mechanical characteristics of rocks from the bench; working conditions, characterized mainly by mining and extraction methods applied; functional parameters of the mechanical equipment used to perform various operations on the coal face etc. For this study it was necessary a broad field for task tracking, measurement, research and design elements of the coal face, for land survey and a desk activity by: processing of topographic data, laboratory analyses on physical and mechanical properties of rocks and numerous specialized studies. In the final part, we bring some contributions to elucidating the issues of special importance for the lignite coal pits of Oltenia, coming up with data, graphics, formulas, solutions and concrete dimensioning of coal faces in terms of using technology in a continuous flow.

Aug 1, 2013

By F. Flores

With the World Summit for Sustainable Development planned for 2002 in mind, nine of the world's largest mining companies decided to initiate a project to examine the role of the minerals sector in contributing to sustainable development, and how that contribution could be increased ? the Mining, Minerals and Sustainable Development Project (MMSD). This project assumed from the start that sustainable development could provide a useful framework to guide the minerals sector which main goal was integrating economic activity with environmental integrity, social concerns, and effective governance systems. The broad steps of MMSD project strategy can be grouped into four major categories: increase understanding of sustainable development; create organizational-level policies and management systems for implementing the principles of sustainable development; collaborate with others with common interests to take joint steps towards sustainable development, and; increase our ability to work towards sustainable development at the local, national, and global levels. In opinion of the article's author, to go ahead with the MMSD strategy and achieving the sustainable development objectives, it is necessary to consider the concept of self-organization, fundamental of the emergent new scientific paradigm, and the consequent epistemology and values that conform a supporting culture for sustainable development.

Jan 1, 2007

By Gordon Nelson

The Homestake gold mine is one of the largest and oldest continuously operating gold mines in orth Ame rica. To date this mine has produced in excess of 128.000.000 tons of ore containing almost 34 million ounces of gold . Gold mine ralization is restricted to the Homestake Formation. This unit is a metamorphosed iron-formation which is enclosed by pellitic metasedime nts below (Poorman Formation) and a pellitic to qua rt zitic unit (Elli son Formation) above. The e ntire Precambrian sequence. in the Lead area. has been subjected to a multi-stage defo rmation episode which ha c reated an extremely complex structural setting for the Homestake orebodies. Metamorphic grade inc reases from greenschi st ro amphibolite in a northeast d irecti on acros the mine area. Present thickness of the Home take fo rmation va ric from O to »400 fee t. The amount of thicke ning and th inning which is attributable to tectonic deformation or original sedimenta ry di fferences is not known. Orebodies constitute onl y a small pe rcentage of the Homestake Formation and do not occur along a pa rticul ar stratigraphic pos ition within the unit. Gold i assoc iated with inc reased py rrhotite and a rsenopyrite concentrations within the iron formation. Inc reased \ cin qua rt z development and chl oritic alteration usuall y accompany this minerali zation. Local remobilizati on of mine ralization due to metamorphi sm has occurred. Homestake mine ralization has been shown to be of sy ngeneti c origin . Because no feeder zones have yet been recognized a di stal source for the mine ralization is inferred .

Jan 1, 1986

By Tommee Larochelle, Henry Kasaini

"Simulation of rare earth element solvent extraction processes for plant design and optimization is complex, requires extensive bench scale and pilot scale testing, and is traditionally performed using proprietary algorithms. The complexity of simulation is mainly due to traditional simulation software solvent extraction modules not being designed to simulate rare earth separation processes because of the interaction between each element. This paper presents an alternative method for designing and optimizing rare earth element solvent extraction separation processes using METSIM to converge each stage of the battery individually until the full battery reached ultimate convergence. A feed-forward controller is used to control the organic to aqueous flow ratio feeding the solvent extraction modules. This method minimizes the complexity of simulating such processes by using inexpensive batch solvent extraction data, and allowing for rapid theoretical optimization, by varying the process configuration and parameters from a graphic interface instead of the traditional code-based interface of most proprietary models. Comparison of the model predictions to pilot plant data reveals that the method can be used to accurately model rare earth solvent extraction processes, as illustrated by its application in the development of Rare Element Resources innovative process.INTRODUCTIONThe Rare Earth Elements (REEs) consist of 16 metals, specifically the 15 lanthanide elements and yttrium, which is typically found in the same mineral deposits as the lanthanides. Scandium can be associated with the rare earth elements, but is usually only present in trace amounts, and therefore omitted. The term “rare earths” originates from an old term used to designate minerals (earths) and their believed scarcity upon their initial discovery. The rare earths designation is now considered a misnomer because it was demonstrated that the crustal abundance of some rare earth elements, such as cerium, is known to be higher than many common metals, such as copper. However, enriched deposits are fairly uncommon compared to other similarly abundant metals. The REEs are typically divided into groups commonly consisting of light rare earths (LREEs), medium rare earths (MREE), and heavy rare earths (HREEs). Light rare earth elements include lanthanum to neodymium, medium rare earths include samarium to gadolinium and the heavy rare earth elements include terbium to lutetium, and yttrium. The REEs exhibit similar chemical characteristics and are usually extracted from the ore and processed into a mixed rare earth concentrate. The rare earth concentrate requires further processing in order to separate the REEs from each other and produce a series of single element products."

Jan 1, 2016

By Alessandro Navarra

Discrete event simulation provides a computational framework in which the use of smelting equipment can be analyzed and optimized, leading to the development of alternative modes of operation. Much of the complexity of copper and nickel smelters is centered on the converter aisle. These converters operate in parallel, produce batches, and set the tempo for the downstream operations. In practice, smelter staff schedule daily operations to coordinate the smelting furnaces and converters with downstream operations. Thus, a realistic simulation of smelter operations, over hundreds of days, should incorporate converter scheduling algorithms as presented in this paper.

Jan 1, 2014

By Yan Qun, Chen Xiao-ming, Ma Pei-long, Luo Xian-ping, Luo Cai-gui, Feng Bo

The effect of leach promoting reagent LPF on the leaching process of a weathered crust elution-deposited rare earth ore has been investigated and the mechanism is discussed. The result shows that the leach promoting reagent LPF can enhance the leaching extraction of rare earth ore effectively. With the addition of LPF to the lixiviant at a concentration of 0.1%, the leaching extraction increased by more than 8%, the ammonium sulfate concentration could be decreased by 25%, and the leaching liquid/solid ratio reduced by 34%. The mechanism analysis shows that LPF can react with rare earth ions and form soluble coordination compounds, thus reducing the activity of the leached rare earth ions, increasing the concentration difference for ion diffusion, and promoting the rare earth leaching process. These results will hopefully help point to a new approach to making the leaching process of low-grade weathered crust elution-deposited rare earth ore more efficient and with lower lixiviant consumption.

Jan 1, 2014

By P. R. A. Andrews, R. K. Collings

"In cooperation with le Ministère de l'Énergie et des ressources, Québec, le Centre de Recherches minérales, Sainte-Foy, Québec, and various silica producers, selected deposits of Quebec silica were identified in the southern region of the province and sampled to provide material for evaluation as glass and foundry sand by CANMET. The samples included both sandstone and quartz/quartzite. Head sample analyses ranged from 94.66% to 99.54% SiO2, 0.038% to 0.230% Fe2O3, and 0.16% to 4.51% Al2O3.Impurities included pyrite, iron oxides, and iron staining on quartz grains; carbonates as calcite; and alumino-silicates as clay and/or feldspar. Processing included size reduction to grain size, about 600 µm, by jaw, roll and cone crushers, and grinding in a muller-mixer. Removal of fines was achieved by attrition scrubbing and washing. Further removal of impurities was achieved by reverse flotation of iron oxide and alumino-silicate minerals employing both anionic and cationic collectors. Flotation resulted in a substantial improvement in the quality of most sands, the quartz concentrates analyzing 99.08% to 99.80% SiO2, 0.014% to 0.048% Fe2O3, and 0.06% to 0.49% Al2O3. Removal of iron oxide minerals was also investigated using the Sala HGMS. Iron oxide analyses of the non-magnetic fractions were comparable to the iron oxide analyses of the quartz concentrates obtained by flotation, 0.013% to 0.054% Fe2O3. On the basis of the samples submitted, silica from 5 of the 6 deposits studied has potential as source material for glass sand. Foundry tests showed that 3 of the 4 samples submitted for evaluation have potential as foundry sand."

Jan 1, 1987

By C. D. M. Chisholm

Introduction The Sullivan orebody is a sulphide replacement deposit in beds of argillaceous quartzites. The general strike of the vein is north and south, with rather an abrupt change to northwest in the north limits, and a pronounced steepening of the dip in the same area. An east-west section across the orebody in the vicinity where the change in strike occurs will show the dip-to the east-to be about 10° to 20° above the 4500 level, 20° to 30° between the 4500 and 3900 levels, and 35° to 45° between the 3900 and 3500 levels. It is this last section, averaging 75 feet in thickness, that is being mined by the blast hole method discussed in this paper. Typically, the mineralization throughout this section follows the same general pattern between footwall and hanging-wall, there being solid sulphides for a width of 30 to 50 feet, above which lie quartzite beds of varying widths separated by ore bands which also vary in width and in grade. This banded part of the vein usually extends for 30 to 40 feet above the solid sulphides, with commercial ore terminating on reaching a siltstone bed. Development is generally carried to the highest ore band which, when averaged with the underlying quartzite band, will assay about the marginal limit in lead and zinc. When wide stopes are opened, sloughing to the siltstone usually occurs and, although the values are too low to carry the cost of developing and mining, the caved muck can be handled profitably with only haulage and treatment to be considered.

Jan 1, 1946

By Lawrence B. Cochrane, Olivier Tavchandjian, J. Michael Anderson, Christopher R. Davis

"Abstract - Resource modelling is a complex process involving different specialists with relevant experience using a multi-disciplinary approach and the best available technology and reviews by independent auditors. The reliability of the final resource estimate is highly dependent on the quality control exercised at each stage of the process. At each step in the resource modelling process it is necessary to define the specific objectives, the methodology proposed to achieve those objectives and to establish a set of checks and validation tools to assess the effectiveness of the proposed methodology. Designation of responsibility and authority for meeting these objectives must also be clearly identified. External audits must also be incorporated to review and validate the implementation of new procedures.Resource modelling is the basis for any economic appraisal of a mining project and includes a number of steps from data acquisition and validation to resource reporting, classification, and risk analysis."

Jan 1, 2001

By Y. A. Topkaya

In this research work, a process was described for the recovery of copper and zinc in copper converter flue dust from the Black Sea Copper Works' Samsun Smelter Plant. After characterization of a representative flue dust sample, the process included roasting of the flue dust and then leaching in dilute sulfuric acid solution. Roasting time and temperature were studied to determine the optimum roasting conditions. Sulphuric acid concentration, duration, temperature of leaching and solid to liquid ratio were the parameters studied in the bench scale laboratory leaching experiments.

Jan 1, 2007

By M. Tanaka, H. Narita, T. Fuchikami, K. Morisaku, K. Nagao, T. Yoshida, K. Kuroda

The effect of various N-substituents on the performance of amide-containing tertiary amine compounds in the extraction of Rh(III) from HCl solutions was investigated to optimize the structure of these compounds for industrial use. It was found that N-2-ethylhexyl-bis(N-di-2-ethylhexyl-ethylamide)amine and tris(N-di-2-ethylhexyl-ethylamide)amine, which have long, branched alkyl chains, were suitable for Rh extraction, because they were soluble in a practical diluent (80 vol% n-dodecane?20 vol% 2-ethylhexanol) and stable against highly concentrated HCl/Rh solutions, and showed high selectivity for Rh(III) over Pd(II) and Pt(IV).

Jan 1, 2014