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By Dave Bulled, Khiratt Husain

"The use of High Pressure Grinding Rolls is gaining significant interest as a replacement for SAG milling in the comminution of hard rock ores because of the potential for reduced costs in terms of energy and grinding ball consumption. Estimation of expected energy consumption for fullscale operations has conventionally involved the testing of a few fairly large samples in pilot scale HPGRs. This paper describes the development of a small-scale batch test method for determining a work index for HPGR of a large number of samples that can be used to show the variability of the ore as an integral part of a geometallurgical approach to circuit design and production forecasting.The test equipment that was developed comprises a hydraulic press with adjustable pressure operating on small batches of ore in a locked cycle test procedure. A work index measurement was determined that links the specific energy consumed in the test to the breakage achieved such that the index can be used to predict comminution energy requirements.The measurements were calibrated against laboratory scale HPGR equipment to develop a model for design and forecasting that includes crushers, HPGRs and ball mills in a complete comminution circuit.INTRODUCTIONEstimation of the expected energy consumption for full-scale HPGR operations has conventionally involved the testing of a few fairly large samples in laboratory and pilot scale machines (Danilkewich, 2006). With the financial input of five mining corporations, SGS Lakefield Research has developed a small scale test capable of providing relevant information on the variability of energy consumption and size reduction from drill core samples. It is our intention that the values measured in the test will be scaled up, through benchmark comparison with pilot sized and full sized HPGR units, to allow plant design and throughput forecast on a block by block basis of the mine plan using a new CEET program. CEET® (an acronym for Comminution Economic Evaluation Tool) is an advanced grinding design and performance predicting tool that uses energy relationships to model the performance of SAG / Ball mill circuits."

Jan 1, 2008

By I. Haskett

ABSTRACT The Redwater pool, in north-central Alberta, was discovered in October, 1948, and at the end of 1950 was about 85 per cent developed. Production is from a Devonian coral limestone reef and is found at an average depth of 3,150 feet. The pool has an estimated .productive area of 37,000 acres, and a maximum oil zone thickness of slightly over 200 feet. Wide variations exist in both type and values of porosity, with the average value determined for the reservoir being 6.16 per cent. The total stock tank oil in place is about 1.24 billion barrels. The crude has a saturation pressure of 485 psig, com-pared to the original value of 1,050 psig for the reservoir, and the principal recovery mechanism so far has been the natural water drive. Cumulative production to January 1st, 1951, has been about 15.5 million barrels. These withdrawals resulted in a reservoir pressure decline of slightly over 100 psi. Predictions of future behaviour indicate that the water drive will not be of sufficient magnitude to maintain the reservoir above saturation pressure past 1953, and that, with natural depletion, the pool will be produced largely by a solution gas drive. Pressure maintenance by water injection has been considered and the possibility of raising the pressure to the original value of 1,050 psig is also discussed. INTRODUCTION WITH the discovery of the Lewduc pool, early in 1947, the Devonian limestone became the major geological formation contributing to Western Canada's rapidly growing petroleum reserves. Redwater, discovered in October, 1948, is now the largest known Devonian pool in Canada, with a recoverable reserve estimated at approximately 500 million barrels. Until recent years, the knowledge of the nature and characteristics of this type of limestone reservoir has been comparatively limited.

Jan 1, 1951

By Jeanie Wills, Theresa Nyabeze, Samantha Espley, Donna Beneteau

This presentation reports survey findings that aim to modernize the definition and understanding of the term 'mining.' The survey, conducted via LinkedIn in Winter 2024, garnered responses from a diverse group of individuals, including current or former employees of mining or exploration companies, mining consulting firms, service providers, supplier firms, as well as students and retirees with industry experience. The data, ethically approved by the University of Saskatchewan, offers valuable insights into satisfaction levels within the mining sector and suggests an expansion of the identifying characteristics of definitions of mining. This marks the third CIM gaining insights paper by Beneteau, Espley, and Nyabeze, following previous works on 'Career Satisfaction for Women in Mining' (2010) and 'Mentorship Initiatives in the Canadian Mining Industry' (2018*)."

Oct 1, 2024

By Y. Özçelik

Rocks show a variety of engineering and physical properties that affect typical quarry operation such as diamond wire cutting in the marble quarry. The physical and mechanical properties of rocks depend on their mineralogical and petrographical characteristics. The purpose of this study is to investigate the effects of mineralogical and petrographical properties of a rock, such as grain size and mineral content, and how these affect the wearing of diamond bead and cutting rate in a diamond wire cutting operation in a marble quarry. Statistical analysis is used to carry out the study. Three different rock types were examined, namely, hard rock (andesite) and softer rocks like limestone and marble. The study revealed that the mineralogical and petrographical properties of the rocks, such as percentage of quartz, biotite, plagioclase, matrix minerals, and opaque minerals, are important. In addition, the grain size of quartz and plagioclase in andesitic rocks and calcite grain size for carbonate rocks significantly influenced the wear rate and cutting rate in diamond wire cutting operations.

Jan 1, 2005

By Vicki Tschirhart, Bill Morris, McMaster University

A new method for mapping faults within basement rocks underlying the Thelon Formation and glacial overburden was developed and tested in the Aberdeen Sub-basin. This method utilizes newly acquired aeromagnetic data, the Blakely algorithm for defining magnetic source edges, a calculated dip-direction map, a digital elevation model (DEM) derived from the Canadian Digital Elevation Database, and the positions of identified, inferred and newly mapped faults that are within and adjacent to this sub-basin. Combining these data revealed three age groups of faults. One group is seen only on the DEM; these faults are young brittle structures that have no effect on the sub-Thelon basement unconformity, and are not visible on the dip direction map. A second group is evident on the dip direction map but not the DEM; these faults are old basement structures that did not propagate upward through the Thelon Formation. The third group is expressed on both the DEM and dip direction map; these faults are also old structures that propagated upward during and/or after deposition of the Thelon Formation. The latter group of faults may be of greatest interest for uranium exploration, with reactivation increasing their potential to serve as conduits to transport uranium-rich fluids and focus deposition at or near the unconformity surface. This methodology has promise for comprehensive mapping of basin faults and tracking the tectonic development of the whole Thelon Basin through time.

Jan 1, 2013

By John R. Goode

"This paper reviews options for the separation of a mixture of rare earth elements (REE) into its component elements. Earlier separations used selective chemistry such as double salt precipitation and reductive/oxidative processes – methods that still have a place in the industry. Fractional crystallization was developed for more complete separations of adjacent REE. The latter method was replaced by ion exchange (IX), which was in turn replaced by solvent extraction (SX). Two main SX chemistries are in use, solvation and cation exchangers, with several variants (mixed solvents, ionic liquids, etc.) now under investigation. SX plant configurations have evolved including advanced techniques like “hyperlinking”, novel saponification methods, and alternative stripping techniques. The classic mixer-settler is the most commonly employed device although centrifugal contactors have been pilot-tested. Non-dispersive SX options including microfluidic devices and membrane-assisted SX techniques are being developed and could revolutionize the SX option. Other REE separation techniques now being studied include Molecular Recognition Technology (MRT), Free Flow Electrophoresis (FFE), newer IX systems, and electrolytic processes. Additionally, the classical crystallization and selective precipitation methods and newer bacteria-mediated processes, chloride volatilization, high performance liquid chromatography, and magnetic separation systems have been studied. This paper reviews the options and concludes that conventional SX is the technology of choice but viable alternatives could be demonstrated and acceptable within a couple of years.INTRODUCTIONThe chemical properties of the individual REE are very similar which is why REE minerals and ore deposits almost invariably contain a mixture of all fifteen REE, i.e., La to Lu plus Y. That said, the distribution of REE in a given deposit is frequently dominated by the light REE (LREE, i.e., La to Nd). Examples include the Bayan Obo, Mianning, Lynas Mt. Weld, and Molycorp Mountain Pass deposits where heavy REE (HREE – Sm to Lu and Y) typically account for well under 5% of the REE content. The LREE operations produce some HREE but the main sources of these important elements are the ionic clay deposits of Southern China. Importantly, all of the REE recovery operations referenced above, except for cerianite-bearing ionic clay deposits, initially produce a mixed REE precipitate or calcine with a REE distribution similar to that in the ore (Goode, 2016). However, the consumers of the REE, the manufacturers of magnets, phosphors, catalysts, optical glass, etc., require separated products with purities generally ranging from 99% to as high as 99.9999% depending on the element in question and the end use. Hence there is a need to separate the individual REE one from the other. This paper is intended to review the options."

Jan 1, 2016

By K. W. Edwards

The formulation of a theoretical basis for the evaluation of in-situ coal through the use of geophysical logs is outlined. This involved the development of an approach to the interpretation of resistivity in environments having multiple conductive and non-conductive components. Utilizing this approach and other conventional interpretation techniques, a program was developed yielding accurate determinations of the in-situ percentages of coal, water and ash for the evaluation of coal deposits. Basic information obtained from the CWA program can be utilized in numerous aspects of total mine planning . Some examples of the practical application of this method are included.

Jan 1, 1978

By Vu Van Dong

Resource estimation is the science of determining the amount and quality of a given material in the ground that has the potential to be mined at a profit. This is because during this time computers have become more widely available and more powerful and software packages have become more comprehensive and user friendly. Over the past three years The Mining Geology Company with the support from Vinacomin Group has developed the Coal Geological Modelling and Reserve Estimation ? VMG system. The VMG system enables the geological and mining engineer to start at the reserve estimation for the mine design and planning. The VMG system enables the national and international standards (NI43-101, CIM-Canada; SAMREC Code, Africa, and JORC Code, Australia) and user friendly with menu driven thereby permitting the engineer with minimal computer training to rapidly learn and utilize the system. Geological and mining data input through digitized map files and drill-holes information files stored in the database that is an integral part of the VMG system with the main function for collection, validation, and recording, storing and processing of data will include both ?primary? (observation and measurement) and ?interpreted? data. It is recommend that data be stored digitally, using a documented, standard format and a reliable storage medium that allows for easy and complete retrieval of the data. The coal reserve estimation through standard polygon methods with the increased use of these mathematical techniques (geometrical modelling, geostatistical method, least square method, ?) over the last ten years corresponds, to some degree, to a decrease in both the amount of the coal deposit mapping and, in particular, coal seam structural interpretation and modelling, and permit rapidly evaluation of coal seam and overburden quality and quantity. The understanding of the relationship between the coal mineralization of interest and the likely related complicate geological processes and structure that govern its emplacement and geometry within the geological framework is essential to the establishment of the geological controls for coal mineralization. System outputs includes: drillholes summary reports, stratigraphy, cross-sections, isopach maps, structure, contour maps, premining and post mining topography maps, and 3D perspective view on coal seam structure.

Oct 1, 2009

By R. C. Fernandes, F. L. Santos

Aluminum alloys in particular, have certain limitations when subjected to welding process. This is mainly present because aluminum alloys have high thermal conductivity, high contraction in solidification and high hydrogen solubility. Taking this into account, the FSW process has great potential for this application, since it is autogenous, held without metal melting and without the use of slags or shielding gases. From this concept, the aim of this study is to evaluate the joining of thin sheets of aluminum alloy 3105 H26 with 0.7 mm of thickness. To performing of the tests, some parameters were analyzed, such as: tool penetration in the sheets, attack angle, the type of welding tool and penetration control mode (position or force). The results indicated that the force control mode is most suitable for thin sheets, and the transient state at the beginning of welding was the most critical part to control the welding quality.

Jan 1, 2015

By S. Banisi, M. Poorkani, M. Farzaneh, M. Askari

"At the Sarcheshmeh copper mine 40,000 t of ore per day with an average grade of 0.9 % Cu is ground to 70% passing 75 microns. Grinding is effected in 8 parallel lines of 8 x 5 m ball mills in a closed circuit with cyclones. The make-up balls are 80-mm forged alloy steel balls and the average ball consumption is 750 gh of ore ground. In order to optimize ball size distribution inside the mill, based on the previous investigation instead of using only 80 mm make-up balls a combination of 80 and 60 mm (75% to 25% by weight) ball charge was used in one of the mills. To evaluate the performance of three ball types namely forged alloy steel balls (A), ductile cast iron (C), high chromium cast iron (D) and also a combined (80 and 60 mm) charge of forged alloy steel balls (B), four identical parallel mills were charged accordingly. These four mills were sampled during a period of six months. The amount of material finer than 75 microns of cyclone overflows was selected as a criterion for the performance evaluation. It was observed that in a mill with the combined make-up balls the amount of fine produced was 4% higher than the other mills. The consumption of ball types A, C and D were 730, 710 and 534 g/t, respectively. The results of laboratory flotation tests showed that due to an improvement in the production of fines an increase of 1.4% in the overall copper recovery is obtainable. Due to the promising results, the new make-up ball regime was implemented in all mills in the plant.INTRODUCTIONThe Sarcheshmeh copper ore body which may rank as third or fourth largest in the world contains 1 billion tonnes averaging 0.90 % copper and 0.03 % molybdenum. It is located southeast of Iran and has been processing 40,000 t/d of ore since 1982. The mine produces 100,000 tonnes of copper and 2,200 tonnes of molybednite concentrate per year. After three stages of crushing, the ore with a F80 of 12.7 mm is fed to 8 parallel ball mills in closed circuit with cyclones to produce a product 70% finer than 75 microns. The concentrate of the first stage of flotation is reground and the tailing constitutes the main component of the plant final tailings. A concentrate with an average grade of 31% Cu is obtained after cleaning and re-cleaning stages. Total recovery of the plant varies between 83 and 87 % depending on the operating conditions and ore type."

Jan 1, 2002

By Roger V. Pierce

IN the last few years, much study has been devoted to increasing stoping efficiency. The reasons for this are shortage of manpower, shorter working hours, operating regulations, and shortages of essential materials. More efficiency in mining methods is needed to offset these adverse factors. In the past, attention has been centred upon haulage, hoisting equipment, mill flow-sheets, etc., but recently the spotlight has been focused on the cost of stoping and the cost of handling materials. Scrapers and scraper hoists have thus assumed greater importance. In order to make it possible for certain orebodies to be mined at a profit, it has been necessary to apply assembly-line practices to the streamlining of mining methods. All cycles of the mining operation must balance, and the sooner broken ore is removed from the working face, the sooner another round can be started. Since the introduction of scraper hoists in metal mines more than thirty years ago, much progress has been made in their design and application. Alert operators are now constantly watching for methods in which to apply scrapers. The saving of manpower in development work and the changing of mining methods that once employed manual handling of materials are increasing vital wartime tonnages. Essential ores from newly discovered orebodies are moving rapidly from stopes to reduction plants-because it is now possible to develop an orebody and place it in production with a minimum of manpower and development work. Today, speed is one of the prime essentials o mining. Everywhere, there is a concentrated effort to use experienced miners in breaking rock, in timbering, and in carrying out the various phases of mining that require many months of training. Much effort is being made to mechanize the working places because experienced men naturally prefer to work where the majority of materials are handled mechanically. In line with this policy, many new men are being taught the details of scraper work, because even green men can quickly become acquainted with scrapers and thereby release older heads to perform the more skilled phases of mining.

Jan 1, 1943

By Greg Yuriy

Over the past two decades, Vale Canada has used discrete-event simulation in a key role to support many underground mining studies. Traditionally, general purpose simulation software was developed for manufacturing and service applications. Not until recently have Mine Designers and Simulation Specialists been able to model the dynamics of underground mining scenarios without extensive manipulation of the inherent tools and entities contained within these simulation environments. This paper discusses Vale Canada?s past experiences with a variety of simulation software, describing model development methods and highlighting some of the lessons learned. The paper concludes with a review of recently considered software and provides a framework of desired attributes/functions for modeling mining scenarios.

Aug 1, 2013

By M. Lundström

The Outotec HydroCopper® process is a novel technology, developed and registered by Outotec Technology Oy, for leaching copper from chalcopyrite using cupric chloride solution. The leaching process is operated at atmospheric pressure in a stirred tank reactor, at temperatures near the boiling point of water and pH values between 1.5 and 2.5. During the leaching of chalcopyrite in cupric chloride solution, a reaction product layer forms on the mineral surface. In the present work, the formation and the composition of the reaction product layer was studied in an environment similar to that of the HydroCopper® process. The effect of the process parameters on the reaction product layer was investigated. Electrochemical measurements, including A.C. impedance spectroscopy and microscopic observations were carried out and an equivalent circuit was used to determine the surface parameters, such as the reaction product layer capacitance and the charge transfer resistance. The results suggest that, at low pH, a passivating sulfur-rich layer forms, whereas at high pH, a more porous iron-rich layer was detected. The values measured can give useful information for optimising the leaching parameters of the HydroCopper® process. Cu2007

Jan 1, 2007

By S. Kariyawasam, R. McNealy

Pipelines are subject to multiple threats often requiring quantification of pipeline risk and engineering evaluation of in-line inspection and other data to effect discovery of conditions defined by the regulation. Public concern and pressure from regulatory bodies are accelerating the need for pipeline operators to formalize and intensify their approach to integrity management. Most operators need a phased approach to progressively adopt the most relevant and needed assessments. The organized and relevant assessment steps need to be introduced according to data available and maturity of the integrity management program. Each refinement to the quantification offers distinct advantages to the user. In this paper, the progressive integrity assessment solutions using quantitative methods are presented. Methodologies for engineering evaluation of integrity in-line inspection data for immediate and future integrity are summarized. Corrosion is used as an example, but the approach is applicable to any time-dependent defect based hazard. Strategies for pipeline integrity management are discussed.

Jan 1, 2005

By J B. McConnell

The Thompson smelter has three unique features which form the basis ~f its design: fluid bed roasters which treat nickel concentrate filter cake from the mill, as well as the flux, in order to achieve partial desulphurization; the use of electric furnaces for the smelting of the partially desulphurized, preheated roaster product; and the disposal of slag by water granulation and slag slurry pumping. The installation consists of three fluid bed roasters, each feeding an electric furnace. Nickel concentrate is received at the smelter via pipe line. It is thickened and filtered, and the filter cake, together with siliceous flux, is fed through rotary bin feeders and reciprocating double-gate seals into the fluid bed roasters. Air injected into the roasters through club-head tuyeres oxidizes part of the sulphur and associated iron in the concentrate. The heat of reaction dries and heats the charge. Roaster product is recovered from the gas stream in cyclones and from the roaster bed through automatic valves.

Jan 1, 1963

By M. Krasowska

Dynamics of collision and kinetics of the bubble attachment to hydrophobic solid plates (Teflon) of different surface roughness were investigated. The experiments were carried out in such a way that probability of the collision and probability that the detachment will not occur were equal always 100%. Thus, it was possible to determine effect of the surface roughness on the bubble attachment (three phase contact formation, TPC) only. A high-speed camera (1182 Hz) was used to record the velocity variations, bouncing and time of attachment of the bubble colliding with Teflon plates having different surface roughness (5 different plates). Roughness of the plate surfaces was modified in a mechanical way using different abrasive papers. It was found that the roughness had a crucial influence on the time-scale of the TPC formation and attachment of the bubble colliding with the Teflon plates. Despite high hydrophobicity of all plates (contact angles 1100 -115º) it was observed that at the smoothest surfaces (called "Teflon I" and "Teflon II" and having surface roughness below 1 um) there was no attachment during the bubble first collisions. Prior to the attachment four or more "approach?bouncing" cycles of the colliding bubble were observed there and simultaneously the bubble shape varied rapidly within time intervals below 0.85 ms. Time of contact of the colliding bubble with the Teflon plates was very short; 2-3 ms. These results indicate that during that short time of the collision the liquid layer separating the colliding bubble and the solid surface did not reach a critical thickness of its rupture.

Jan 1, 2006

By A. Poitras

The Cummings Complex consists of three superposed sills, exhibiting a differentiation pattern: the lowest sill being the most basic and the highest sill, the most acid. Each sill is also characterized by an internal petrographic and geochemical variation which is evidence of differentiation due to fractional crystallization. The REE concentrations in the different units of the complex indicates that the three sills are comagmatic. The interpretation of these results permits the formulation of an emplacement model not previously proposed for this complex.

Jan 1, 1984

By Ron Light, Doug Applett

"HistoryThe Nanisivik mine began operation in October 1976 as the world's most northerly metal mine and the first permanent industrial project in the Canadian High Arctic. Located 700 km north of the Arctic Circle on Baffin Island's Strathcona Sound, exploration by Texasgulf Inc. between 1957 and 1970 had outlined the ore deposit. In 1974, Nanisivik Mines Ltd. was formed with Mineral Resources International, the Government of Canada, Metallgesellschaft and Billiton being shareholders, and Strathcona Mineral Services Ltd. providing project management. In 1996, Breakwater Resources purchased the mine from Alberta Energy Corporation Limited which had recently acquired the assets of then owners Conwest Exploration Ltd.Ore DepositThe main ore deposit is very flat, approximately 80 m in width and varying in thickness from 3 m to 16 m. The length of the deposit is approximately 3000 m with satellite zones located on the perimeter of the main zone. The economic mineralization is sphalerite with minor galena and silver. The sphalerite and galena are coarse grained and associated with pyrite as the main gangue component with minor inclusions pf dolomite and calcite within the deposit. The deposit being hosted in a permafi·ost environment creates a number of challenges. Dry drilling is employed in room and pillar production drilling. The permafrost aids in the stability of both the pillars and the back."

Jan 1, 2000

By M. Leroux, P. Lacombe, S. R. Rao, J. Y. Kim, J. A. Finch, G. Labonté, N. Macminn, M. Ounpuu

"Laboratory investigations on two complex ores, the A1 zone ore from Les Mines Selbaie and the Lyon Lake ore from Mattabi Mines Ltd. (Division of Noranda Minerals), have been carried out to determine some of the main variables in collectorless flotation. In particular, the effect of pulp potential (controlled by gas composition), conditioning time, pH and grinding media have been studied.Chalcopyrite showed the greatest response to collectorless flotation among the four major sulphide minerals present, followed by galena. Flotation of sphalerite was variable from minimal to important depending on the mineralogy and the pre-treatment performed. Appreciable silver recovery was achieved collectorlessly for the Lyon Lake ore while it could not be achieved for the A1 zone ore of Les Mines Selbaie. It appears that the difference between the two ores is related to silver's predominance as tetrahydrite in the Lyon Lake ore while it is as argentite and native silver in the A1 zone ore.The response of the ores to collectorless flotation is strongly dependent on the pulp potential, Ep, and pH. Using different gas compositions and different conditioning times it was found that collectorless flotation occurs when Ep is +195 to +295 mv (vs SHE). The actual on-set potential for collectorless flotation is dependent on the ore. A too high potential or prolonged oxidation leads to a decrease in selectivity. Some other factors were examined, notably the effect of pH and the type of grinding media on the selectivity achieved in the laboratory.Preliminary results from a plant trial at Mattabi Mines Ltd. confirmed that collectorless flotation occurs and that it is preferential for chalcopyrite and to a lesser extent galena. Collectorless flotation was not attempted at Les Mines Selbaie. However, examination of the distribution of collector between the different addition points in the copper circuit suggests that it may be present."

Jan 1, 1990

By J. -F. Lepage, M. A. Tomlinson, K. K. Murray

"The Éléonore mine, located in the James Bay region of Northern Quebec, generates a gold bearing flotation concentrate rich in pyrrhotite. Direct leaching of the finely ground concentrate results in high cyanide consumptions and poor recoveries, so effective pre-treatment to passivate the pyrrhotite is required before leaching. Following a number of process upsets at the mine, test work was performed to better understand the requirements for passivation so a more effective operational strategy could be implemented. This paper outlines the testing and implementation of the new strategy at Éléonore.ÉLÉONORE CONCENTRATOR The Éléonore mine is located 800 km north of Montreal, in the James Bay Region of Quebec, Canada. The ore, containing gold disseminated in sulfide minerals and free fine gold in silicate gangue, is crushed in a two-stage crusher plant before being ground in a single 9,000 kW ball mill. The ball mill is in closed circuit, with about 25% of the cyclone underflow passing through a gravity plant with two, 48” Knelson concentrators. Gold recovery in the gravity circuit varies between 15 and 20%, with gravity concentrate leached daily in an Acacia intensive leach reactor. Cyclone overflow, at a target P80 of 65 microns, flows to the flotation plant where the gold bearing sulfide minerals, mainly pyrrhotite and arsenopyrite, are recovered to concentrate with a mass pull of about 5%. The flotation concentrate, typically containing between 80 and 120 g/t of gold, is thickened and finely ground using a 1500 kW Isa Mill. The finely ground concentrate is diluted, to generate a slurry with about 32% solids by weight, before feeding the leach plant. Initially the concentrate slurry is pre-treated with oxygen and lead nitrate, to passivate the sulphide minerals before cyanide is added for gold dissolution. Gold is recovered from the leached slurry using carbon-in-pulp (CIP). The flotation tailings are also thickened and gold is recovered in a dedicated leach-CIP plant."

Jan 1, 2017