Search Documents

By Z. D. Hora

Numerous asbestos occurrences are known, and the Cassiar Mine in Northern British Columbia has been a major producer since 1952. The Kutcho Creek deposit is a large medium-grade deposit of potential economic interest. OF THE numerous British Columbia asbestos occurrences, only one mine exists. Another property, at Kutcho Creek, may be commercially viable. Cassiar Mine, in the northern part of the province, has been producing high-quality asbestos since 1952 and is described elsewhere in this volume. The Kutcho Creek property is situated north of Letain Lake about 125 km southeast of Cassiar Mine. The Kutcho Creek asbestos deposit comprises zoned chrysotile fibre veins in a well jointed and locally sheared serpentinite sill. The sill intrudes, more or less concordantly, a sequence of Devonian to Mississippian argillaceous Industrial Minerals in Canada metasedimentary, calcareous, and volcanic rocks. The light to dark green serpentinite contains crossfibre chrysotile veins that are usually less than 1 cm in width but up to several metres in length. Typical sections in exploration drillholes grade between 2.5 and 3.0 per cent fibre. According to the last assessment report submitted, test results indicate that the Kutcho Creek property may contain a large, medium-grade asbestos deposit of potential economic interest.

Jan 1, 1984

By W. A. Alexander

Introduction In the course of a programme of research on beryllium in progress in these laboratories, knowledge of the recrystallization temperature became necessary. As the information is not available in the literature, the determination of this temperature for metallic beryllium was undertaken. By the reduction of grain size through working and recrystallization and the probable simultaneous induction of preferred orientation, it was hoped to improve the working properties of beryllium at lower temperatures. The recrystallization temperature is usually determined by observing the lowest temperature of annealing at which new crystals are formed in severely cold-worked metal or alloys. This temperature is profoundly influenced by the following factors: the purity of the metal, in the case of an element, or the composition of the alloy; the degree of straining or working; the temperature of straining; the original grain size; and the time held at the annealing temperature. The observed temperature is lowered by higher purity, more severe straining, lower temperature of working, smaller original grain size, and longer time of annealing. Beryllium presents special difficulties in that the percent elongation in tension is effectively zero, so that ordinary squeezing or rolling was not possible. A possible means of straining was suggested by the fact that indentation hardness tests could be made. It was known from earlier work that the metal could be worked at elevated temperatures, so that working at the lowest feasible temperature and quenching might also be a means of producing strain. The purity of the metal is also a point of some uncertainty in the case of beryllium. Losano has prepared 99.96% Be which appears to be the best reported. Distilled metal used in the present work approached this purity. However, by analogy with other metals, residual impurities may have a pronounced effect on the recrystallization. Further purification of beryllium would evidently entail considerable difficulties due to the highly reactive nature of the metal, and was not attempted.

Jan 1, 1947

By Jianping Zhang

QUESTIONS: ?? Is it more expensive to find an ounce of gold in Canada today than 50 yrs ago? ?? Did the Canadian gold industry find more gold than they mined? ?? What is the future sustainability of the Canadian gold industry? ANSWERS: ?? The gold discovery costs in real terms only increased slightly from 1946 to 2000. ?? Though the Canadian gold industry mined more gold than they discovered in the period, when undeveloped deposits are taken into account, the deficit was merely 12 million ounces. ?? The Canadian gold mining industry would be sustainable in the foreseeable future, particularly, given the overwhelming predicted promising gold market in the mid/long run.

May 1, 2006

By R. Butar-Butar, J. Mosher, G. Banini, J. Hollow, A. Villanueva

The effect of High Pressure Grinding Rolls (HPGR), as a preceding stage to a conventional ball mill circuit at PT Freeport Indonesia’s C1/C2 concentrators, has been studied in terms of downstream grinding efficiency and circuit performance. When milling the product from the HPGR, mill capacity increased by 21% for the same product grind size, when compared to processing similar ore from a conventional crushing circuit. This achievement is a result of several reasons, among them: reduction in feed size (F80), fines generation beyond the proportional reduction in F80, reduction in ore hardness induced by HPGR comminution mechanism, optimization of the recycle system of the HPGR and ball string optimization in the ball mill circuit given the new feed to the mill.

Jan 1, 2012

By N. Plint, D. Philips, J. Sweet, B. Durant

A pilot scale AG milling campaign was conducted at the AngloAmerican Platinum pilot plant in South Africa. Different blends of hard: soft (silicate: chromite) and coarse: fine particles in the AG mill fresh feed were tested. The effects of multi-component feed on the pilot scale autogenous grinding are presented in this paper, and can be used as a guideline for multi-component feed blends for AG mil

Jan 1, 2012

By D. J. Parker, G. B. Tupper, I. Govender

Positron-Emission-Particle-Tracking (PEPT) has enabled the non-invasive observation of charge and slurry transport in model mills under operational conditions. We use high quality PEPT data to infer that the charge motion can be effectively described by a non-Newtonian granular fluid. An improved theory for slurry transport, including inertial effects, is presented.

Jan 1, 2012

By P. R. Warner

This paper reviews the development of certain aspects of the electrical specifications of Anglo American’s suite of specifications for gearless mill drives (“GMDs”). These specifications are based on experiences in both Anglo American’s and others’ operations, benchmarking against large hydro generators, the advice of industry and university experts, and continuous close co-operation with OEMs. To achieve a step change in availability additional final testing and electrical protection have been implemented, insulation requirements have been specified for machines to be operated at high altitude and clean area and access control systems have been developed.

Jan 1, 2012

By J. M. Cooper

The HBMS reverb furnace in Flin Flon was originally designed in the late 1920s. Throughout the decades campaign life has been increased due to operational practices, technological changes and brick quality improvements. In recent decades the campaign life had been extended such that a complete rebuild was scheduled every 3 years. The latest furnace rebuild and start up has been after a campaign life of nearly 6 years. Brick construction methods and techniques along with furnace operational practices allow the present campaign to be double that of the historical campaign length.

Jan 1, 2007

By A. Fakhimi

The effect of porosity on mechanical behavior of rock has been studied in the past using both experimental and numerical techniques. One important aspect of this study that has not received much attention is the role of void size and distribution on the mechanical behavior of rock. In this study, the CA2 computer program that is a hybrid discrete-finite element program for two-dimensional simulation of geomaterials is used. Numerical specimens with different macro-void sizes are loaded uniaxially. The Young?s modulus, Poisson?s ratio, uniaxial strength and crack initiation stress are studied. The numerical results are compared with the database of experimental tests on Plaster of Paris specimens containing Styrofoam spheres with different void sizes and porosities. It is shown that the macro void spatial distribution is partly responsible for the scatter of the experimental data. It is also shown that not-only the porosity but also the pore size can affect the deformability, crack initiation stress and rock strength.

May 1, 2009

By Paul Delottinville, Maynard Hall, Henry Hillier

"An expert system application for supervisory control and optimization of the indurating process at the Iron Ore Company of Canada (IOCC) has been developed and installed in closed-loop. Prior to the installation of the expert system, the indurating machine was rebuilt and the instrumentation revamped. A Foxboro I/A Distributed Control System (DCS) was installed for regulatory control, and a new control strategy configured. The modernization of the regulatory control has resulted in significant improvement in both production rate and product quality. Expert system control was implemented in September 1996. Preliminary indications are that the expert system has further improved the consistency of product quality, enhanced fuel efficiency and increased productivity. The expert system considers both wet and dry sections of the circuit, and its optimization scheme is driven by pellet tumble index and compression strength. Statistical Process Control (SPC) rules were implemented in the expert system as part of the quality analysis and control scheme. The expert system application was developed and delivered using the Comdale Expert Optimizer (CEO), and has been in continuous closed-loop control since its installation. The system development and implementation is described, and preliminary benefits are presented..... IntroductionIn early 1996 the Iron Ore Company of Canada (IOCC) contracted Comdale Technologies of Toronto to develop and implement a real-time expert system for optimizing the indurating pelletizing furnace at our plant location in Labrador City, Newfoundland.The decision to install the expert system has been timely. Like many other resource-based industries in increasingly competitive markets, IOCC recognizes the need to find ways to improve the efficiency of our production process and ensure that product quality is maintained at the highest levels. With the Labrador City plant producing 11 million tons of iron ore pellets annually, implementing the best technology solutions to meet these objectives is critical."

Jan 1, 1998

By Bonnie Cooper

3D printing by fused deposition can be used on lunar soil. The soil can be precisely size-separated to make the 3D printing process work efficiently. Using a MASER instead of a LASER would allow us to use the finest fraction of lunar soil, AS-IS, to manufacture things on the Moon.

May 1, 2013

By T. McCallum, B. Wellbrook, T. Ratnaweera

Leaching of copper (Cu) concentrates produces elevated concentrations of Cu and acid, which makes solvent extraction (SX) processing more challenging. Maintaining extraction targets can be more difficult with higher pregnant leach solution (PLS) grades, and variability of PLS Cu and acid can lead to increased chemical iron transfer. Diluting concentrate leach feeds with an existing heap leach inventory makes SX processing easier. However, considerations about how much to dilute and where to distribute the flow into the SX configuration must be carefully evaluated, given their impact on metallurgical performance. In this paper, characteristics of a concentrate leach feed are discussed, along with considerations for processing by SX. Also reviewed are pilot plant results of concentrate leach distribution into SX and plans for commercial testing. INTRODUCTION Hydrometallurgical processing of copper concentrates continues to gain interest from the industry. Treatment by smelting and electrorefining continues to dominate, accounting for ~80% of global copper production, but is faced with its own challenges (Li et al, 2017). The case for increased hydrometallurgical processing has been discussed as high grade ore deposits are diminishing, capital costs for smelting are high, and the environmental aspects present challenges for sustainable practice. The hydromet copper industry is also turning a corner as easily leachable copper oxide deposits are depleting, and excess SX-EW capacity exists in certain regions. The transition to hydrometallurgical processing of copper concentrates will take a bit of effort as leaching of copper sulfides is difficult and byproduct credits must be considered. Various POX leaching processes have been studied and proposed to the industry as viable practices. Of the many processes, commercial use has been practiced with the Mount Gordon Copper Process, total and partial pressure oxidation by Freeport-McMoRan at their Bagdad and Morenci, Arizona complexes, the Sepon Copper Process in Laos, and the bioleach BIOCOP™ process in Chile (Dreisinger, 2016).

Jan 1, 2019

By R. Tessier, R. Grant, C. Bazin

"Brunswick Mining has investigated grinding media optimization for the purpose of improving the flotation feed and regrind product size distributions to enhance metal recoveries. The paper presents findings in the on-going testing of various sizes and shapes of grinding media. Breakage rates are used as an aid to assess the effect of grinding media. Results of empirical and phenomenological analyses demonstrate the importance of adequate selection of media sizes on the milling operation.INTRODUCTIONBrunswick Mining and Smelting operates one of the world's largest lead and zinc mine near Bathurst, New-Brunswick. The No. 12 ore body is an extremely fine grained volcanogenic massive lead, zinc, copper, silver, iron sulphide body between two metamorphosed sedimentary and felsic volcanic rock units. Pyrite content is about 60% with 20% non-sulphide minerals, mainly silica and chlorite. The operation is currently processing 10,500 tonnes of ore per day in conventional crushing, grinding, differential flotation and dewatering circuits. Details on the circuit can be found elsewhere (e.g. Hendriks and Ounpuu, 1985; Grant et al., 1991).The mill has operated for more than 25 years and despite the past milling experience, there has been much disagreement as to the required grind size. Since 1964, fineness of the flotation feed ranged from 60% to 80% passing 400 mesh (37µm) and averaged slightly over 71%in1992. Results from mineralogical analysis (Petruk and Schnarr,1981; Coleman, 1988), Brunswick metallurgical laboratory (Grant et al., 1991; Shannon et al., 1992) and Lakefield pilot plant tests (Hendriks, 1984; Hendriks and Ounpuu, 1985) clearly indicate that improved metal recoveries can be achieved by an increase in the fineness of grind, and more specifically by maximizing the amount of material in the 15-25µm range."

Jan 1, 1993

By Tim Robinson, Michael S. Moats, William G. Davenport, Andreas Filzwieser, Andreas Siegmund, Shijie Wang

This survey continues the long tradition of providing a snapshot of operating data from industrial electrorefineries. It is a supplement to previous surveys that were performed in 1987, 1991, 1995, 1999, 2001, 2003, 2007, 2010, 2013 and 2016. Analyses of current data and historical trends are presented. Examples of innovations to reduce costs, improve productivity, and improve quality are provided. In general, refineries continue to increase productivity while treating anodes with more impurities. INTRODUCTION This manuscript analyzes global survey data provided by operating copper electrorefineries. This paper continues a series of surveys of copper refining tankhouses that started in 1987 (Schloen, 1987, 1991; Schloen & Davemport, 1995; Davenport et al., 1999; Robinson et al., 2003; Moats et al., 2007, 2013, 2016). In this installment, data collected from 2015 and 2018 will be presented and analyzed. The 2015 survey data were presented at Copper 2016 in Kobe, Japan. This survey will continue the analysis of previous data to illustrate long term trends in copper electrorefining, which were originally presented at the Davenport Symposium in October, 2014 (Moats, Robinson, & Wang, 2014). Refineries who supplied surveys are listed in Table 1. Cathode production data from 2015 and 2017/18 (from surveys presented in 2016 and 2019) are provided to indicate which plants provided surveys and when. This manuscript presents operating data for ~6.5 million tonnes of copper production, which represents 30–35% of the world’s copper electrorefining production. The detailed survey results are available upon request from the corresponding author.

Jan 1, 2019

By Xuanxue Mo, Kaihui Yang

"The Laochang mine, located in the Sanjiang area of southwestern Yunnan Province of China, is a volcanogenic massive Pb-Zn-Cu sulfide deposit. It is hosted by a pyroclastic sequence of Early Carboniferous age, namely the lower member of the Yiliu Group, which was intruded by syenite and rhyolite porphyry. The volcanic suite is basaltic or basaltic-andesitic in composition, has alkaline affInities, and is associated with the initial rifting along the margin of the Baoshan-Shanstate continental microplate (Yang, 1989). The ores are typically Pb>Zn>Cu in composition, averaging 3.820/0 Pb, 3.51% Zn, from 0.01% to 1.85% Cu (0.107% av.), a high average content of Ag (113 glt) and recoverable amounts of Au, n, Gd, Ga, Ge, In. A massive sulfide zone, in which lenticular and stratiform orebodies are localized in a sulfide-<:arbonate-silica shale unit or sulfidic tuffIte horizon that usually overlies coarse-grained pyroclastic rocks, is underlain by a stringer sulfide zone developed in a subvolcanic intrusion or volcanic sequence. The sulfIde mineral assemblages, from the top to the bottom of the deposit, are: realgar + orpiment - galena + sphalerite + pyrite - chalcopyrite + pyrite + pyrrhotite + arsenopyrite. Oxide and sulfate minerals occur rarely in the massive ores. The massive ores are generally fme-grained and banded, but coarse-grained ore, colloform and framboidal texture, and growth-zoned pyrite and sphalerite are common. Sedimentary features such as graded bedding, brecciated and deformed ore clasts, and chaotically emplaced blocks, are well preserved, indicating that the massive orebodies have undergone slumping and displacement. Alteration is weak in the hanging-wall rocks, but strong in the stringer zone. Two distinctive alteration zones have been identifIed: the upper zone, characterized by an assemblage of quartz, carbonates, chlorite, albite, zeolite and sericite, and the lower zone containing diopside, tremolite, actinolite, gamet, clinozoisite, and epidote.The general features of the Laochang deposit are in accord with the descriptive model of VMS deposits (Lydon, 1984). However, it falls into neither the Zn-Cu group nor the Zn-Pb-Cu group chemically (Franklin et al., 1981). The depositional setting of the Laochang deposit is quite different from Cyprus or Besshi-type massive sulfide deposits. Laochang is hosted by alkaline lavas that were erupted in a submarine continental rift. Although some features of the Laochang deposit are similar to those of Kuroko-type deposits, there are remarkable differences in the alteration mineral assemblage, the proportion of ore-forming elements (lead enriched) and the amounts of oxides and sulfates. These suggest corresponding differences in ore fluid composition and the associated ore-forming environment. Thus, the authors suggest that the Laochang deposit may be a distinct type of VMS deposit."

Jan 1, 1993

By T. G. Joseph, R. K. Soni, M. Curley

"Rapid dampening suspension is a proposed suspension design for ultra-class haulers that is intended to avoid metal-to-metal contact inside a strut and under shock loading, thus improving ride quality and ameliorating fatigue loading issues on a hauler structure. Laboratory testing has shown the ability of the proposed design to reduce the opportunity for bottoming out, that is, metal-to-metal contact between the colliding ends of oleo-pneumatic, two-piece suspension struts during the compression cycle. This paper predicts the performance of a full-size rapid dampening suspension strut by applying scaling rules to test the proposed design based on a set of field data from a Caterpillar 797B ultra-class haul truck operating in the oil sands region of the province of Alberta, Canada. The predicted performance of the suspension strut is compared to that of the original equipment manufacturer model, which was monitored on board the truck during field data collection. ¦ KEYWORDS Haul truck, Original equipment manufacturer (OEM), Rapid dampening, Strut, Suspension RÉSUMÉ La suspension à amortissement rapide est une conception de suspension proposée pour des camions de transport de catégorie ultra-class (des engins dont la charge utile dépasse les 320 tonnes métriques), visant à empêcher un contact métal sur métal à l’intérieur d’une jambe de suspension et dans des conditions de choc au chargement. Elle améliore la qualité du roulement et les problèmes de charge de fatigue sur la structure d’un camion de transport. Les essais en laboratoire ont confirmé que la concep¬tion proposée évitera au cylindre interne de heurter le cylindre externe, autrement dit empêchera le contact métal sur métal des jambes de suspension oléopneumatique en deux parties pendant le cycle de compres¬sion. Cet article prévoit la performance d’une jambe de suspension à amortissement rapide à taille réelle en appliquant les lois d’échelle afin de mettre à l’essai la conception proposée, sur la base d’une série de données de terrain relatives à un camion de transport 797B de catégorie ultra-class de Caterpillar (aujourd’hui remplacé par le nouveau modèle 797F) utilisé dans la région des sables bitumineux de la pro¬vince de l’Alberta, Canada. On compare la performance prévue de la jambe de suspension à celle du modèle du fabricant d’équipement d’origine (FEO), qui a été contrôlée à bord du tombereau pendant la collecte des données de terrain. ¦ MOTS CLÉS amortissement rapide, camion de transport, fabricant d’équipement d’origine (FEO), jambe de suspension, suspensionINTRODUCTION Research basis for the paper This paper is based on the unpublished MSc thesis work of El-Sayed (2003), Santos (2007), and Soni (2009) under the direction of Dr. Tim Joseph within the oil sands–equipment interactions program (OsEIP). OsEIP is part of the Alberta equipment–ground interactions syndicate (AEGIS) surface mining research group, School of Mining and Petroleum Engineering, University of Alberta. The aforementioned work spanned a decade of progressive studies into rapid dampening suspension systems, leading to the scale performance indications highlighted here. Although this paper uses a specific Caterpillar 797B suspension strut for field monitoring and as a basis for scale prediction of a modified rapid dampening suspension strut design, the design scaling principles used here could be applicable to any such design change consideration for an oleo-pneumatic suspension system."

Jan 1, 2019

By M. W. Bartley

"The Steep Rock iron mine is 141 miles west of Port Arthur, Ontario, and 50 air miles north of the Vermilion iron range in Minnesota. The property lies 27'2 miles north of the village of Atikokan on the south line of the Canadian National railway.The orebodies underlying the bed of Steeprock lake, since de-watered, were known to exist 60 years ago. References to the possibility of iron ore at this location were made in early geological papers and reports. In 1937 the locations of the orebodies were determined by dip-needle surveys, and from 1938 until 1943 diamond and churn drilling were carried on to prove their extent and configuration. It was found that the ore, in addition to being associated with definite types of wall-rock, was controlled by structural features, such as faulting and brecciation. From this geological knowledge the presence of other deposits has been inferred, and these are now being explored and developed.Production at the property commenced in October 1944. During that season 17,000 gross tons of ore was shipped. In 1945, 506,000 gross tons and in 1946, 830,000 gross tons was mined and shipped. In 1946, 164,000 gross tons additional was placed on stockpile for future shipment.TYPES OF 0REBODIES AND MINERALIZATIONThe orebodies at Steep Rock iron mine are tabular. They have an average width of 250 feet, lengths up to 5,000 feet, and persist to known depths of 1,200 feet. They are replacement deposits in brecciated carbonate rock at the contact of underlying pseudo-limestones and overlying volcanics. The ore is composed of hematite and hydrous hematite in the form of goethite, turgite, and limonite. These minerals replaced the brecciated host rocks metasomatically as a result of hydrothermal action. The replacement followed a definite structural pattern along the unconformable contact between the sediments or other rock (now replaced by carbonate) and the volcanics, subsequent to disturbances in the form of minor faulting and shearing. The faulting and shearing provided the channels through which the replacing solutions percolated. It is believed that the late basic intrusions outside the ore zones were genetically responsible for the introduction of the ore-bearing solutions."

Jan 1, 1954

By Shinji Muraishi, Shinji Kumai, Yasutaka Kedo, Takashi Kambe

"Magnetic pulse forming (MPF) is one of the extreme high-speed forming processes. A metal sheet which is accelerated by electromagnetic force is collided onto a mold and fine and sharp details of the product can be obtained. The deformation mechanism of the MPFed metal cannot be understood only by the microstructure observation of the deformed metal. The deformation behavior of the metal should be investigated also by considering the local microstructure change with strain, strain rate and temperature change during deformation. Numerical analysis is an effective method to achieve this requirement. In this study, pure Al and Cu sheets were deformed by MPF. Impact velocity of the metal sheet was calculated by using ANSYS Emag-Mechanical. Based on the obtained impact velocity, the deformation behavior of the metal sheet was reproduced, and local strain, strain rate, and temperature were analyzed by using ANSYS AUTODYN. The relationship between the local microstructure change of Al and Cu sheets and the deformation parameters was examined.INTRODUCTIONMagnetic pulse forming (MPF) is one of the high-speed forming processes using electromagnetic force. Fine and sharp details of the product can be obtained, and springback after deformation is extremely reduced in comparison to the conventional forming processes(Psyk, Risch, Kinsey, Tekkaya, & Kleiner, 2011). Figure 1 shows a schematic diagram of MPF. A metal sheet is placed over the coil in the discharge circuit. The discharge current runs through the coil, and magnetic fieldis producedaround the coil. An eddy current is inducedin the metal sheet. Interaction between magnetic field and eddy current creates electromagnetic force. The metal sheet accelerated by electromagnetic forcecollides ontothe mold. Forming is completed in a few tens of micro-seconds.MPF is suitable for metals with a high electrical conductivity like Al and Cu.The MPFed metal may have characteristic microstructure because of high strain rate deformation."

Jan 1, 2018

By Alexander Smith

"The three principal known mineral deposits of the Taku River area lie in the Tulsequah synclinorium. The axis of this north-south trending structure is along Tulsequah River valley; about 6 miles east of the eastern contact of the Coast Range batholith.The one proven mine of the area, the Polaris-Taku, is on the west side of the valley. It is a gold property, the gold occurring in fine needles of arsenopyrite disseminated in carbonatized volcanics. The mine was originally called the Whitewater, and the adjacent area the Whitewater gold belt. During the years 1937 to 1942 gold having a value of $3,284,000 was produced from 313,500 tons of ore milled."

Jan 1, 1954

By Bob Rappolt

Discussion Points Part 1: Global Mining Industry/Related Issues ? Historical Metal Price Trends. ? Historical LME Metal Stockpiles. ? China?s Demand for Metal. ? World Population Growth, Demands and Development. Discussion Points (cont?d) Part 2: Canadian Mining Industry ? Where are we? And where are we going? ? What progress have we made in the past 20 years regarding: ? Safety -Employee Levels ? Labour -Relative Compensation ? Productivity - Technological Advance ? Where do we stand regarding mineral production? ? What does the future hold for us?

Apr 1, 2005