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By M. J. Young, C. A. Aird

"The Gem molybdenum prospect is situated at the head-waters of Clear creek, between the Fraser river and Harrison lake, about 30 miles north of• Harrison Hot Springs, B.C. Clear creek follows a deeply eroded fault zone southwesterly through the center of the claim group. Elevations range from 2,000 feet in the creek bed up the steep slopes flanking the creek to a height of 5,500 feet. The property lies within an area underlain by schists and gneisses which strike from north to west in a broad fold plunging steeply to the northeast. This metamorphic complex has been invaded by numerous bodies of grano-diorite, much of which is gneissic. A granite plug, roughly 2,400 by 4,000 feet in size, has intruded this broad fold just west of Clear creek and encloses a circular breccia pipe 1,500 feet in diameter. In the breccia pipe, fragments of metamorphic rocks, granite and quartz monzonite porphyry are firmly cemented in a matrix of quartz monzonite porphyry. All the above rocks are cut by numerous fractures filled by vuggy quartz veins, many of which contain molybdenite. Attentien was first drawn to the area by a quartz vein, 18 inches in width, known as the Gem vein, which consists of several laminated bands of quartz and molybdenite. Since 1964, exploration efforts have been directed toward attempting to outline a large, low-grade type of molybdenum deposit."

Jan 1, 1969

By M. Timberlake, A. J. Jonaitis

"The DENVER Tube Press is a simple, high pressure (1500 PSI (100 bar)) filtration unit, developed for processing difficult-to-dewater materials and to produce a handleable filter cake and clear filtrate product.Lab and Pilot testwork conducted in Australia on coal fines (55-70% -35 micron (400 mesh)) have shown that total moisture contents of less than 20% are consistently achieved in the final cake products from the Tube Press.currently, these coal super fines are sent to waste due to uneconomical mechanical dewatering methods, which were only able to reduce total moisture levels in excess of 30%. Calculated, throughput rates for the 500 series Tube Press exceeded 1700 kg/hr (3750 lbs/hr). Feed solids concentration requirements are between 45 and 50% to achieve these results.INTRODUCTIONThe DENVER Tube Press is an automatic membrane high pressure filter press, which operates at hydraulic water pressures up to 1500 PSI (100 bar). The Tube Press was developed in the late 1960's by Charlestown Engineering, st. Austell, Cornwall, England, formerly a division of English China Clays, Ltd., to address more effective methods of moisture reduction of micron-size china clays. The Tube Press reduced moisture sufficiently to produce a hard surface-dry, handleable cake and clear filtrate discharge, which was recycled into the process. This development work was conducted using a 200 Series Tube Press (200 mm diameter x 2500 mm long filter surface)."

Jan 1, 1993

By B. I. Whittington

This paper examines the effect of cation type (i.e. NH4+, Na+ and K+) and anion type (i.e. SO42- and C1-) on the extraction of nickel during the pressure acid leaching of a Western Australian laterite ore. The results are compared with testwork conducted with other Western Australian nickel laterite ores and the possible process implications of adding an additive to a plant autoclave are considered. Addition of either (NH4)2SO4, Na2SO4 or K2SO4 increased both the nickel extraction and the acid consumption, provided that the level of additive was not too great. For example, the nickel extraction of 93% increased to above 96% in the presence of additives, but decreased to 94% when, for example, NH4 levels increased from 7 kg/t ore to 21 kg/t ore. The relative stability of the jarosite species formed when additives were present influenced the amount of jarosite in the residue and, hence, both the final free acidity and overall nickel extraction. The use of Cl- versus SO42- salts as additives had little effect on overall nickel extraction or overall free acid values, although the presence of SO42- additives appeared to enhance nickel extraction kinetics over the first 60 minutes of the reaction. In contrast, manganese extraction was enhanced by the presence of Cl- additives.

Jan 1, 2004

By Marcio Luis S. Godoy

The Salobo Project will be the first Vale operation to use an HPGR mill to process copper-gold ore. The mine is located in Para state, southeast of the Amazon region in Brazil. The circuit was designed to treat 12 million metric tons per year of finely disseminated sulphide ore with high hardness. The comminution circuit comprises a gyratory primary crusher, secondary crushing utilizing two cone crushers, two 2 x 1.5 m HPGR operating in closed configuration with 6 mm screens, followed by two 26 x 40 ft ball mills. The concentration circuit consists of two rougher flotation stages using mechanical cells, regrinding with vertical mills, three cleaner stages with columns and one cleaner scavenger stage in mechanical cells. The concentrate is dewatered, filtered and transported by trucks and train to the port, to be exported. The circuit was designed on the basis of data obtained from a comprehensive laboratory and pilot plant campaign. The ore variability was assessed through simulation using data from a drilling core characterization program. The start-up of the industrial plant is planned for 2011. This paper describes the main aspects of circuit design, as well as information related to the beginning of the project construction.

May 1, 2010

By S. Tuttle, R. Sisson

"Suncor Energy Inc. has proposed a 2.2 billion dollar expansion to the current oil sands operation, which will more than double the productive capability of the facility. As part of the application for this expansion, a comprehensive closure plan had to be developed and filed.Closure planning includes a systematic evaluation of the area to be developed, the development activities planned, the goals and objectives of the corporation in re-establishing landforms and ecosystems at the same time as running an effective operation. As early as is practical during the mine development, surface contouring is completed, soil is reconstructed, and vegetation, surface drainage and wetlands are re-established. Once active reclamation is complete and vegetation has been re-established, Suncor monitors maturation of landscapes and ecosystems to provide the submission basis for reclamation certification"

Jan 1, 1999

By M. A. Bergougnou, I. Inculet, K. I. Burgess

This paper describes the electrostatic methods of separating various minerals, reviews the principles of fluidization and outlines the technique of electrostatic sorting in fluidized beds. The application of the method to the benefication of coal is emphasized.

Jan 1, 1970

Accurate hematite solubility data are required to construct predictive solution chemistry models for complex hydrometallurgical solutions. These data are useful in understanding Fe(III) speciation and precipitation in a variety of hydrometallurgical processes. Hematite solubility data were generated in 10 to 70 g/L H2SO4 solutions and at temperatures from 130 to 270°C, using specially modified titanium autoclaves. These measurements represent an improvement over previous experimental data because of better in-situ filtration of the sample aliquots, the approach to equilibrium via hematite dissolution, and the inhibition of Fe(III) reduction on titanium surfaces. Fe(III) reduction was particularly studied to evaluate the inflationary effect of Fe(II) on hematite solubility measurements. Chromate was found to reliably inhibit Fe(III) reduction on titanium. Finally, the generated hematite solubility data were used to construct a solution chemistry model using the OLI software.

Jan 1, 2006

By W. J. Mcgaughey, M. A. Vallée

"Abstract -The application of geophysical technology to resource delineation aims to improve the quality of resource/reserve estimates by integrating high-resolution survey methods, geophysical modeling and inversion with three-dimensional representations of geological and mineral deposit data. The use of geophysics can cost-effectively improve a geological interpretation based only on geological and sampling data. Success depends upon the ability to use geological visualization and modeling software, first to develop a three-dimensional geological model and then to modify it interactively by integrating geophysical data with the geological and sampling data.The high resolution required for mineral delineation geophysics results in a focus on borehole seismic and high-frequency electromagnetic methods. Borehole wireline logging is used to develop an understanding of the relationship between physical properties and geological description. Data from core samples and borehole wireline logs allow the construction of a three-dimensional physical property distribution, consistent with the existing geological interpretation. The three-dimensional physical property distribution is used for both geophysical forward modeling (to compare to field data) and as a starting model in iterative inversions.Advanced visualization techniques allow the simultaneous viewing of the three-dimensional physical property model, the geological information and data from which it is derived, and the geological interpretation and the geophysical results. Geophysical results may be simulated responses from a forward model or the output from a numerical inversion in the form of an updated physical property distribution. Iterative refinement of the geological interpretation is required to ensure consistency with the geological and geophysical data. The key to success with this approach is that all relevant geological, geophysical, and rock property data reside in a common, visual model of the earth.Examples from massive sulfide deposits illustrate the benefits obtained by the integration of geophysical and geological data."

Jan 1, 1998

By M. Härting, D. T. Britton, M. Nzikou Mamboukou

"Copper containing different types of nanocomposites have been characterized for nanolabelling and ID. Three types of the rare earth nanoparticles were used for this study, the oxide and the sulphur compound of the Eu and Tb. Characterization techniques uses SEM, and Raman for morphology, chemical composition, and optical characterization respectively. It has been shown that it is possible to include the rare earth particle in a copper matrix without damaging its physical properties. INTRODUCTIONThe development of new materials, often involves the addition of new properties without changing the beneficial properties of the original material (Chen et al., 2009; Khana et al., 2007; Patil et al., 2008). Nanocomposites are nanostructured materials, whose structural elements including clusters, crystallites or molecules, of dimensions ranging between 1 to 100 nm (Moriarty, 2001), or a composite material where one of the phases is a one, two or three dimensionally nanostructured material (Nanotechnology, 2006; Wang, 2001). Nanocomposite materials research is a fast growing area due to the high demand for materials for specialized applications (Edelstein & Cammarata, 1998), such as biolabelling, magnetic storage media, solar energy transformation (Jisen et al., 2004), and resistance welding applications (Bessergenev et al., 1997; Kwon et al.,2006).The properties of the nanocomposite materials depend not only on the properties of their individual parent materials, but also on their morphology and the interfacial characteristics. Thus, significant efforts have been focused on the control of the nanoscale structures via innovative synthesis approaches. Therefore, novel materials of unique properties may be obtained by combining properties from the parent constituents into a single material (Balan, 2006; Garcia et al., 2009). Possible effects of nanocomposites in the original material may include changes in the mechanical properties such as hardness , wear resistance (Rafaja et al., 1987), and electrical properties (Britton et al., 2003). The inclusion process may therefore be used to tailor materials to have particular mechanical, electrical and optical properties (Das et al., 2009). However, to fully understand the nanocomposite, it is necessary to study the fundamental properties of both the host matrix and the inclusions (Li, 2008)."

Jan 1, 2012

By Shek N. Lau, Nicola Samman

"Enclosed gear cases on board heavy mining equipment have traditionally been lubricated with regular heavy duty gear oils. However, equipment manufacturers, have recommended the use of an ISO-1000 gear oil for this application to ensure adequate lubricant film strength, especially at the higher end of the working temperature range. The majority of these ISO-1000 gear oils are based either on residual/asphaltic oil or synthetics, primarily higher viscosity polyalphaolefins. Although the performance of these lubricants has been satisfactory, they suffered other shortcomings that equipment users have lived with over the years.The major requirement at the user’s mine was to provide lubrication for the shovel Hoist gear case. Within such a gear case design, the gears and the roller bearings, that have different lubrication requirements, are lubricated with the same lubricant. Several lubricants were used, light gear oils as well as the recommended ISO-1000 heavy gear oils. On the one hand, the lighter oils performed adequately for the lubrication of the bearings that formed part of the enclosed gear system. These lighter oils did not perform as well for the lubrication of the gears due to their lower viscosities, resulting in shorter gear servicelives.On the other hand, the ISO-1000 gear oils performed well for the lubrication of the gears, but were too viscous to creep into the bearing elements to lubricate them adequately, especially during the cold northern Canadian winters. This resulted in catastrophic bearing failures and secondary damages to the gears.The challenge, then, was to formulate a lubricant which met the 1000 cSt at 40°C viscosity requirement as stipulated by the equipment manufacturer, while satisfactorily lubricating the bearings at the full working temperature range. This was achieved by the development of a semi-fluid grease lubricant, which has proven in field trials to give adequate performance in this application for the lubrication of both the bearings and gears down to -40°C.This product met the equipment manufacturer’s performance criteria and resolved, to a large extent, leakage of the lubricant through seals experienced with the use of conventional and synthetic gear oils.Although the main performance criteria of the fluid was its capability to lubricate the “Hoist” gear case, it was also used during the field trial in other gear cases on board the shovel to test its full capabilities.This unusual alternative lubricant was field tested and evaluated for more than two years. Based on this assessment, the product was reformulated to improve its fluidity, slumpability and the settling of debris/wear metals to the bottom of the gear cases. This reformulated softer grade, a semi-fluid grease, has been performing satisfactorily for more than eight months and is still undergoing longer term assessment."

Jan 1, 1996

By Gorrell. H. A.

Subsurface water data can be very valuable in .petroleum exploration and research. For the discussion of problems related to subsurface waters uniform nomenclature and classifications are required. The term 'connate water' has frequently been incorrectly used. It should .only be used in its original sense in which it is analagous to 'fossil water'. Classifications .based on origin and on sodium-chloride content are proposed. Present and possible uses of formation water analyses are briefly discussed. Since the potential uses of formation water data are not fully understood, complete analyses of selected samples should be made to insure against future requirements. The subsurface waters of Alberta show considerable regional variation in amount and proportion of dissolved salts.

Jan 1, 1958

By Yve Fourmanoit

"This paper discusses the exploitation of shallow underground deposits in a very altered geological environment. The methods, their adaptation to local conditions, their evolution, dilution control and recovery of mineral reserves will all be dealt with.The recovery of the B zone crown pillar under 40 m of till that was originally saturated with water, is of particular interest.Future underground development and production start-up of the A-2 zone, organization of mining operations, mechanical services, group incentives and safety practices will also be given.IntroductionThe underground deposit of B zone is not very deep. A 300 m shaft provides access to the mine. In addition , exploitation sublevels are developed every 20 m and are linked by a service ramp. The overburden located on top of the deposit is 40 m thick and is composed of a very dense till.A detailed work plan was initiated to permit mining under the overburden. To do so, it was imperative that efficient methods be developed. At a time when an accident at the Belmoral Mine shook the mining world , it was a task to convince provincial authorities that it was safe.While B zone was being mined , development began in the A-2 zone deposit which has recently been put into production (Figs. 1 and 2).The intention of this paper is to provide an outline of the mining method s and their particular aspects. To do so, some of the mine services are described and a brief outline of the under ground department is provided."

Jan 1, 1990

By M. P. Tibbs

An autonomous spray application system for a structural Thin Spray-on Liner (TSL) is targeting productivity and safety on underground coal continuous miners by potentially replacing steel mesh, and has broader applications as surface support and confinement in metalliferous mines and civil tunnelling. Polymer chemistry, coating formulation, geotechnical assessment and the autonomous application system are being developed as an integrated package as part of a continuous miner automation project. This polymer-based TSL system has significant benefits over conventional steel mesh skin confinement, including being more automatable by spray application, providing complete skin confinement and active skin reinforcement as a fast-curing composite with substrate, and having effective fire retardant properties for the polymer and the underlying coal. This paper presents a preliminary assessment of distance sensing systems that would enable autonomous adaptation of a nominal spray path to spray a consistent thickness of TSL (nominally 5mm) over an irregular topography. Two alternate sensors are assessed; firstly, a 2D LIDAR mounted on a linear axis is used to produce a 3D surface profile for generating an adapted spray path; and secondly, a robot end-effector-mounted ultrasonic sensor is assessed for wall following techniques to dynamically adapt a nominal spray path.

Aug 1, 2013

By \/eena Sahajwalla, Jonathan Dicker, Paul O'Kane, Cath Skidmore, James Dankwah, Magdalena Zaharia, Rita Khanna, David Knights, N Saha-Chaudhury, Somyote Kongkarat

Due to the inherent limitations of current methods of disposal of end of life polymeric materials, avenues are researched towards developing alternative, environmentally friendly and economic recycling processes. Different polymeric materials (i.e. rubber, high density polyethylene (HDPE) and polyethylene therephtalate (PET)), quite distinct in terms of chemical structure and composition, were considered in the present study as carbon resources in EAF steelmaking. Investigations were conducted in both laboratory and industrial scale steelmaking to assess the effectiveness of using these materials as carbon sources for slag foaming in EAF steelmaking. Slag foaming is important because it enhances furnace efficiency.

Jan 1, 2011

By Omero Alonso-Gonzalez, Sergio Haro-Rodriguez, Ricardo Solis-Rodriguez, Francisco Alvarado-Hernandez, Juan Antonio Gonzalez-Anaya, Héctor Rene Vega-Carrillo

"Precious metals are currently associated with refractory minerals such as telluride (Calaverite, Sylvanite, etc.) and selenium (Naumannite Ag2Se), which are difficult to dissolve through traditional methods, therefore it is necessary to perform a pretreatment (oxidative or roasting) preceding the process of leaching by cyanidation. In this preliminary work the aim was to study the use of solvent extraction to remove tellurium and selenium ions from a synthetic cyanidation effluent, with the purpose of recycling the cyanide back to the process. For the extraction of these anions, TeO32- and SeO42-, tallow trimethyl ammonium chloride (Quatarmina TPR) and hexadecyl trimethyl ammonium chloride (Amine F) were studied as extractants, using nonylphenol as a modifier in the organic phase (trimethylpentane). The results show that it is possible to recover 82% of selenium and 10% of tellurium from synthetic solutions containing either 20 mg/L Se or 20 mg/L of Te, respectively The Se or Te mole ratio to cyanide was 1:4.INTRODUCTION In relation to extraction of precious metals, the cyanidation process has been in use for over a century and despite environmental and toxicological problems it remains the most widely used and economical process available. In the late 90s, there were great efforts to recover gold and silver from refractory ores, which is difficult to do by simple cyanidation. To improve gold recovery from tellurides and selenides that occurs in some new mines, the ores are pretreated by roasting. This is one of the most effective ways of rendering refractory gold ores leachable as well as being a fast pretreatment process compared with bio-oxidation or pressure leaching (Aylmore, 2001). The most important tellurides minerals are Calaverite (AuTe2) and, Silvanite (Au, Ag)2Te4). In the case of selenides, minerals include Naumannite (Ag2Se) and Aguilarite (Ag4SeS) (Ostroumov et al., 1989). Examples of deposits containing telluride include La Bambolla Mine (Sonora, Mexico), Cripple Greek (Colorado, USA), and Kalgoorlie (Western Australia) (Aguayo et al., 1996). The main purpose of this work was to explore the feasibility of using quaternary ammonium salts such as: tallow trimethyl ammonium chloride (Quatarmina TPR) and hexadecyl trimethyl ammonium chloride (amine F) to extract tellurium and selenium anions from aqueous synthetic cyanidation effluents, so that the cyanide solution could be recycled back to leaching process. The tests were performed on synthetic solutions similar to those found in a mine: 20 mg/L Te as TeO32-, 20 mg/L Se as SeO42- and mole ratio to cyanide was 1:4. using an alkaline medium with pH ranging from 8 to 12. Two aspects are evaluated in this paper:"

Jan 1, 2017

By A. Tylczak, C. Norman, C. Shook, S. Loif

"There are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes or malfunctioning equipment early, which allows problems to be corrected promptly.Sacré-Davey Engineering in Vancouver has performed over 50 Energy Management studies for various industries including: mining, pulp and paper, oil and gas, etc. Energy Management programs can be used to identify energy reduction opportunities, assess project feasibility, complete equipment selection trade-offs, as well as to monitor and manage energy costs. Benefits of energy management programs are reduced energy costs, reduced maintenance, and increased plant automation. Additionally, energy management can provide access to utility incentive funding and quantify savings which can greatly improve the return on investment of potential projects.Energy management studies are funded by many Utility programs across Canada. There are various programs available for existing plants energy audits, project feasibility studies, new plant design reviews and energy monitoring and targeting, etc. There are capital incentives available which can significantly reduce payback period.This paper discusses how energy management can be used to support mill/mine operations groups, maintenance programs, as well as expansion or green field projects. This paper will also provide an overview of Canadian Utility companies programs and how they can assist mining companies.IntroductionThere are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes and identify malfunctioning equipment early, which allows problems to be corrected promptly."

Jan 1, 2015

By Rolf Andreas Lauten, Guy Kluck

"Formation of scales may have important detrimental effects in many mineral processing applications. A well-known problem is the need for frequent maintenance to remove scale from processing equipment. Another challenge may relate to encapsulation of valuable minerals in precipitating scale. In this work, we explore the ability of some crystal growth inhibitors to prevent or lower the degree of scale precipitation. In many situations pregnant leach solutions contains substantial concentrations of calcium, magnesium, sulfate and carbonate in addition to dissolved valuable elements, e.g. gold, copper, zinc. Together with non-dissolved gangue minerals, some slurries may also contain particulate gold, copper etc. During normal processing of the pregnant leach solution it may be exposed to temperature gradients or similar promoting precipitation of various scales. Valuable minerals may become entrapped in precipitates and thus become inaccessible to the lixiviant. Use of a crystal growth inhibitor may lower the degree of encapsulation of valuable elements.Using a simple model system, supersaturated with respect to gypsum, the effect of some crystal growth inhibitors on the prevention of scale is evaluated in terms of amount precipitated gypsum, the particle size of the precipitated gypsum and the carbon gold loading capacity.INTRODUCTIONGold bearing sulfide ores are often roasted or pressure oxidised prior to leaching. The purpose of this unit operation is to prevent loading the leaching circuit with sulfides that consume cyanide. Pressure oxidation or roasting chemically converts the sulfides into sulfates and at the same time, the pH of the slurry ends up in the acidic range. Typically, lime addition is the preferred means to raise the pH to around 10 where gold leaching takes place. Combination of large amounts of calcium ions from the lime with sulfate ions from the ore induces precipitation of gypsum. Compounds like calcium carbonate may also precipitate if carbonate ions are present in the slurry. Depending upon the composition of the ore, compounds like calcium carbonate and other types of scale may also precipitate on gold surfaces on the slurry particles. A layer of scale on top of exposed gold surfaces will prevent dissolution in the cyanidation that takes place during leaching. Naturally, such a precipitation may lower the gold recovery."

Jan 1, 2016

By T. Belem

In-stope backfill will cure under effective stress, which develops due to a combination of mechanical consolidation (free draining material) and ??chemical consolidation?? (self-desiccation mechanism). A good knowledge of all the drainage and consolidation characteristics of cemented paste backfill is crucial for a better design of underground backfilling sequencing. From many of the existing results and studies done by various authors, as well as the availability of some in-stope backfill pressure data measurements during and after filling, it is possible of developing a procedure of backfilling sequencing. Hence, the objective of this study is to provide a guide for underground backfilling sequencing in the view of preventing the development of excess pore pressure that will affect both the stability of the barricades and the strength development of the backfill. This will be possible by considering the interaction between consolidation/drainage rate, filling rate and binder hydration rate.

Aug 1, 2013

By B. D. Sparks, I. E. Puddington, F. W. Meadus

The continuous separation of bitumen from Athabasca tar sands, with a high clay content, has been demonstrated. Recoveries of 95 per cent or higher have been obtained. Further processing of this product, to produce an accept-able type of crude oil, would require less heat than currently used in the hot-water process. Also, by comparison, substantial savings in equipment and operating costs are indicated.

Jan 1, 1971

By G. A. Buckland

"The development, in Ontario, of a common industry-wide program for the development of skills for employees in underground hard-rock mining is described. This program is designed to increase the productivity of individual workers by improving their skill levels, while at the same time ensuring that employees are instructed in the requisite safety and health aspects of performing various underground tasks. The program's development through a management-labour-government tripartite approach is described. How this program was coordinated with new Government Regulations on Occupational Health and Safety dealing with mandatory training of underground employees is also outlined. IntroductionThis paper will describe briefly what modular training is all about and outline why, and how, it was developed in Ontario on an industry-wide basis. Simply stated, what's been accomplished to date is an industry-wide program for developing the mining skills of underground production employees.The basic objective of this program is to improve the productivity of underground workers. It involves developing an employee's skills to improve his productivity and, because working productively involves knowing how to do a job safely, the program includes instructing an employee in the various safety and health aspects of underground work. An important and, I believe, distinguishing point about the development of this program is that it has been done with the full participation, cooperation and commitment of management, labour and government.It's of considerable interest to note that companies in Ontario who are now using this program are finding that new employees are approximately six months further advanced in productivity than was the case before its use, and in some cases the frequency of accidents has shown a reduction among those employees who have taken this program as compared to those who haven't"

Jan 1, 1980