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By 000-900-009-492

The flotation has been and is still the most widely used mineral concentration method. Because of its complexity, the flotation process required the development of robust control strategies which was facilitated by the introduction of on-line sensing instruments such as x-ray fluorescence (XRF) on stream analyzer (OSA), gamma density gauges and electromagnetic flowmeters. The interest in developing control strategies has persisted because the benefits to be gained in terms of improved metallurgical performance are substantial. As the flotation control becomes more and more difficult due to the emergence of low grade and complex ore cases, other control strategies have to be introduced. Froth based control is one of the emerging useful control strategy This paper will focus on the state of the art in the on-line froth characterization as obtained by numerical image analysis. The technology of machine vision provides a novel solution to several of the problems encountered in conventional flotation systems for monitoring and control, and constitutes a powerful tool for the investigation and interpretation of the effect of various flotation parameters as driven for the froth phases. Copyright @2001CIM

May 1, 2001

By Gilles Bonin

Structures and serpentinization patterns in the Thetford Mines peridotites are important characteristics indicating the necessary geological conditions which led to the development of chrysotile orebodies in Early Ordovician limes. These structures and serpentinization patterns are reviewed in this paper using the geology of LAB Chrysotile orebodies as a model. Structural aspects include parallel and transverse faults, parallel and transverse granite slabs, and orebodies, some of which trend clearly north-westward parallel to the accretionarymovement. Serpentinization patterns in the peridotite belt, particularly in the harzburgite, include primary pervasive mass serpentinization and secondary complete serpentinization. Listwaenites layers appeared along some faults and along some granite slabs as a result of hydrothermal alteration of the serpentine, following the emplacement of the devonian plutons to the south. These plutons as we/1 as other important lineaments, align with the structural pattern of Thetford Mines ophiolites. It is believed that these plutons are part of a heavy magma tic corridor resembling the Pilote-Mont-Louis corridor in the Gaspe (Doyon and Berger, 1997), and the Buchans' structure in Newfoundland (Hutchinson, 1984), both intersecting the Brompton-Baie Verte line.

Jan 1, 2001

By A. J. Ouellet, A. Coulombe, B. Salmon

The no. 7 vein system cuts the Ventures gabbro which has undergone folding and fracturing; the latter, in response to movement on the nearby Campbell Lake fault. It fills a shear fracture which pinches and swells in the upper mine levels but has a more uniform width in the lower levels. The best copper and gold grades in the upper levels occur in the widest parts of this structure. The vein is richer in quartz on upper mine levels and in carbonate on lower levels. The north wall of the vein is more affected by major and minor element wallrock alteration than the south wall. The isocumulative ci;rves for gold and copper show a direct correlation between the two metals in the upper levels and their increased concentration in the wider parts of the vein. Gold grade decreases in lower levels. A proposed structural model identifies the no. 3 and no. 7 veins as second order conjugate fractures, related to the Campbell Lake fault. The fractures pattern suggests that a conjugate system developed between these two parallel veins as a consequence of rock competence and a relatively low confining pressure.

Jan 1, 1984

By D. H. Ryan, B. Abdul, M. Pernechele, E. Asselin

Hydrometallurgical processing of sulphide concentrates at medium temperature (150°C) produces residues, which contain valuable metals (Cu, Ni) as well as sulphur and iron bearing minerals and phases. The low solubility of iron during the medium temperature processing of sulphide ores can favour the formation of poorly crystalline, nano-scale iron oxide/oxyhydroxide phases. A better understanding of the formation and structure of these iron precipitates may elucidate key factors that would ultimately result in lower valuable metal losses and more stable leach residues. Residues from two medium temperature leach processes were characterized by Mössbauer Spectroscopy. Some portions of the Mössbauer Spectrum were suspected to be linked to jarosite but could not be positively identified as such. There was a broad range of disorder and substitution present in the material and solely attributing it to jarosite proved difficult. Various synthetic jarosites with Cu substitution were precipitated for Mössbauer analysis. These were then characterized by Quantitative X-Ray Diffraction (QXRD), Scanning Electron Microscopy (SEM), Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) and Mössbauer Spectroscopy. The Mössbauer Spectra of the synthetic jarosites is compared with that of the residues from medium temperature (150°C) sulphide concentrate leaching.

Jan 1, 2014

By Somchet Vongpaisal

This paper presents the R&D results on the development of a new knowledge-based system for predicting stope instability and associated unplanned dilution in deep underground mining operations. A new prototype was developed based on databases generated from 3D non-linear elasto-plastic finite element stress analysis, heuristic rules, and case histories. This prototype aims to assist mine operators to make decisions on strategic mine planning and feasibility in a quick and efficient manner thereby minimizing risk on ground failure and optimizing mining costs.

Jun 1, 2012

By Y. N. Zhang

Friction Stir Welding (F SW) is a novel "green" manufacturing technique due to its energy efficiency and environmental friendliness. This solid-state joining process involves a rotating tool consisting of a shoulder and/or a probe. The shoulder applies a downward pressure to the work-piece surface, constrains the plasticized material around the probe, generates heat through the friction and causes plastic deformation in a relatively thin layer under the bottom surface of the shoulder. The rotating probe mainly drags along, plasticizes, and mixes the adjacent material in the stir zone, creating a joint without fusion. Friction Stir Processing (FSP), a variant of FSW, has been developed to manufacture composites, locally eliminate casting defects, refine microstructure and/or improve the associated mechanical and physical properties including strength, ductility, fatigue, creep, formability and corrosion resistance. However, major challenges such as tool design and wear currently limit the use of F SW/P for manufacturing applications, particularly for high melting temperature or high strength alloys. In this review, the FSW/P tools are briefly summarized in terms of the tool types, shapes, dimensions, materials and wear behaviors.

Jan 1, 2011

By M. Harrison, C. H. Stockwell

"Metals vah1ed at more than $200,000,000 have been obtained, mainly since 1930, from the mines of northern Manitoba. The greater part of this production has been copper, zinc, and gold from the Flin Flon, Sherritt Gordon, and Mandy mines. The chief mines from which gold alone has been produced are God's Lake, Laguna, and Gurney. At present (May 1947) Flin Flon and Sherritt Gordon are the only producing mines, but the Nor-Acme property is being developed for large-scale production of gold. Large deposits of nickel and copper are being diamond drilled at Lynn Lake, and the Thompson, Ferro, and other properties are being developed. The mineral deposits lie within irregular or elongated areas of Precambrian sedimentary and volcanic rocks, surrounded by granite ( Fig. 1).The common rock types include basic and acidic flows, agglomerate, ruff, greywacke, arkose, argilli te, conglomerate, and their gneissoid and schistose derivatives. They are invaded by sills, dykes, and irregular bodies of gabbro and diorite, and all are cut by granite. Some of the sediments are interstratified with volcanics, and others are deposited unconformably on them.STRUCTURAL GEOLOGYLittle is known of the structures of the rocks in the area as a whole, because by far the greater part is unexplored or has been covered only by reconnaissance surveys. Available information indicates a general east structural trend in the southeast part, whereas in the west part the folding is mote complex with no definite overall trend. However, in a few small areas in the western part where detailed work has been done, as around the Flin Flon, Sherritt-Gordon, Nor-Acme, and other properties, the structure is fairly well known. The following descriptions apply chiefly to these areas ."

Jan 1, 1954

By Gaston Giuliani, Jérome Massot, Didier Bourlès, Lionel Siame

"Abstract - We present a new approach for the evaluation of the potential of emerald reserves in gem projects using beryllium (Be) mobility. The distribution of Be in the different phases of hydrothermally altered (albitized) black shale hosting Colombian emerald deposits indicates that Be mobility is associated with the breakdown of Fe-Mn oxyhydroxide phases. The amount of Be that can be mobilized (~0.7 x 10-6 g/g; i.e., 0.7 ppm) may represent up to 18 wt% of the total Be contained in the black shale. A mass balance calculation applied to a well-constrained alteration zone of the Chivor mines, and based on the quantification of Be that can be mobilized under hydrothermal conditions, gives an estimate of the total gem reserves of these mines. Resumé - Une nouvelle approche, basée sur la mobilité du béryllium (Be) pour l’évaluation des réserves d’émeraude dans des projets d’exploitation de gemmes est présentée. La distribution du Be dans les différentes phases minérales de schistes noirs hydrothermalisés (albitisés) qui contiennent les gisements d’émeraude colombiens, indique que le Be mobilisable se trouve dans les oxyhydroxydes de fer et de manganèse. La quantité de Be potentiellement mobilisable (~0,7 x 10-6 g/g; soit 0,7 ppm) constitue jusqu’à 18% poids du Be global contenu dans le schiste noir. Un bilan de masse appliqué à la zone d’altération hydrothermale des mines de Chivor et basé sur la quantification du Be mobilisable, donne une première estimation des réserves à émeraude de ces mines. rieur."

Jan 1, 1999

By A. E. Aho

"The material presented in this paper will be subject to modification as new data become available, but it is presented in the hope that it will inspire more intensive mineral exploration and geologic studies of what appears to be one of Canada's richest mineral provinces. A metallogenic province 400 by 150 miles in extent, lying mostly northeast of Tintina trench, encompasses most of the base metal deposits of Yukon, as well as deposits of other metals. Its main features are northwesterly trending arcuate fold belts, with several orogenic axes, which include most of the metamorphosed rocks, granitic intrusives and mineralization; and which are modified by regional uplifts, northwest-striking fault trenches, and lesser transverse folding and faulting.The main base metal occurrences and their regional controls are summarized briefly. Most of the replacement-type deposits are localized in late Proterozoic to early Paleozoic rocks, particularly Lower Cambrian -probably because these are the most physically and chemically favourable hosts encountered in an appropriate temperature and pressure environment; perhaps because of early age of deposition. Most of the deposits also occur near heat sources or intrusives with associated structural uplift, which has, moreover, served to expose the older rocks. They also tend to occur near known or suspected regional fault trenches, such as Tintina, Macmillan and Hess, although this relationship may be fortuitous. In detail, they may be localized in fold axes, flat-lying beds or other appropriate structural traps. Vein-type deposits are fracture-controlled and localized by dilational localfties, the competence of wall rocks and ""damming"" effects.In the Anvil district, large stratiform iron-zinc-lead replacement deposits lie parallel to gently plunging flex-ures in phyllite in a zone parallel to the Tintina trench, along the southwest flank of the arch-like Anvil batholith. About 80 million tons of massive sulphide ore probably existed before erosion of the Faro orebody, the Vangorda deposit could have been of similar magnitude before erosion and much more tonnage probably remains to be discovered in the district. The Anvil deposits may differ from others found to date in Yukon, but resemble the Sullivan orebody of southeastern British Columbia in their large size, localization in essentially non-limy peptic to arena-ceous host rocks of Proterozoic or early Paleozoic age and proximity to the Rocky Mountain -Tintina trench sys-tem. These features suggest an origin from primordial subcrustal sources.More major ore deposits, not only of lead, zinc and copper but probably of other metals as well, will no doubt be found in similar environments in Yukon or Alaska. Thus, the base metal province of Yukon offers challenging opportunities for prospecting, development, field studies and basic research."

Jan 1, 1969

Energy benchmarking is widely applied across industries to determine the potential to improve energy performance. Unlike the many technologies for which energy benchmarks and efficiency rating systems are already in maturity, benchmarking of mining processes is still in its infancy. Benchmarking energy usage in mining operations, where energy costs are high and represent a significant portion of overall operating expenses, is challenging due to the uniqueness of each mining operation. Mines vary in terms of geology, geographic setting, ore body geometry, mineralogy which impact the mining method, material handling, processing and waste management. In order to gauge the opportunity for reducing the energy intensity of individual operations and also to compare the energy performance of operations on a global scale, the deployment of new benchmarking methodologies, models and frameworks is necessary. As a step towards the establishment of an accurate framework for benchmarking the energy consumption of mining operations, comminution, one of the more energy intensive mining sub-processes, was selected as the focus of a new energy benchmarking method. The methodologies and processes used to onset fragmentation in a rock mass to the crushing or grinding of rock to a size that is suitable for economic extraction are predominantly dependent on the ore properties. For this reason, site specific factors, such as the size reduction requirements and ore hardness were included in an energy benchmark model so that the energy performance of comminution processes at different operations could be normalized and compared on a global scale. Single particle compression breakage has been identified by several prominent researchers in the field of comminution as the upper limit of energy utilization in size reduction processes. For this reason single particle compression breakage was proposed as the basis of a work index for ores to be used as an input for the benchmark model. Overall, the new method showed that the energy benchmark for mineral comminution can be normalized and subsequently compared for a range of mining operations once the ore hardness has been appropriately characterized.

Aug 1, 2013

By Andrew J. Troop

"VAUGHAN THOMPSON designed the Thompson retrievable diamond drill wedge and reaming assembly in 1948. Since 1950, the Hudson Bay Exploration and Development Company, Limited has used the method extensively. The wedge, setting tool, and reamer have been modified slightly since they were first introduced. In 1951, Mr. Thompson designed the Thompson arc cutter. The purpose of this tool is to decrease effectively the diameter of the arc cut, using standard drilling tools. This directional drilling device is usually employed when a branch hole is desired. The Thompson arc cutter has been used with success at Birch Lake, Saskatchewan, at the property of Cuprus Mines, Limited, Manitoba, and at Thompson Lake, Manitoba.UsesThe Thompson retrievable wedge provides a simple method for:(1) Re-drilling lost core sections(2) Re-sampling sections of old holes(3) By-passing lost tools Correcting the direction of a hole(4) Drilling a branch hole to obtain intersections at a higher elevation than the original holePrevious to the spring of 1951, the wedge was used only for the first four of these purposes. Recently it has been employed extensively for drilling branch holes."

Jan 1, 1953

Some Statistics ? Feasibilitystudiescostbetween2% & 3% of capital andrequire8% to15% of total engineering effort ? Feasibilitystudiesusuallytakebetween8 and16 months ? Historically more than80% of projects fail to achieve all their objectives, usually blame the feasibility study ? What is bankable? Means that your promises will long be remembered. ? Poorly executed feasibility studies ? Driven by inexperience, unrealistic expectations, time constraints, financial constraints, lack of objectivity, front end loading activities incomplete or poorly done ? lack of minimum standard to provide a consistent approach Trend to improve???

May 1, 2010

By Arthur Laing

"IT is indeed a pleasure to have the opportunity of addressing this group today. Not only does it give me the opportunity of meeting with representatives of what is considered by many to be the most dynamic segment of industry in Canada today, but it also allows me to talk about a subject of para-mount interest to myself, the development of the North, and to explain, if even only briefly, some of our beliefs and hopes in this regard.It is inconceivable that all lands north of the 60th parallel, representing 35 per cent of Canada's total land area, which we believe contain a great natural resource potential, will remain as an undeveloped portion of Canada. The re-sources are there, although the people and private industry are as yet not there in sufficient numbers.It has been estimated that in the west and north of Canada there are 1.6 million cubic miles of sedimentary rocks. Of this figure, 342,-000 are thought to lie in Alberta, 115,000 in British Columbia and about 1 million cubic miles are thought to lie in Canada's northern regions, the bulk in the Arctic Islands. On the basis of apparent volumes of sedimentary rock, we estimate that as much as 13 billion barrels of petroleum may lie beneath the permafrost of the North-west Territories, another 3 billion barrels in the Yukon Territory and 33 billion barrels in the Arctic Islands. This is, indeed, a rich and elusive prize, and one which must be sought with a view to fulfilling demands on the production of petroleum."

Jan 1, 1966

By Renaud Cousin

Supported gold catalysts were prepared by Direct Anionic Exchange on an alumina support and tested during the reaction of CO oxidation and of saturated and unsaturated hydrocarbons (C1 to C3). The catalysts showed high activies over a range of concentrations and temperatures compatible with an application to automotive exhaust cleaning. Furthermore, a complete resistance to thermal ageing at 600°C in the absence or presence of water was observed due to the obtention of strongly anchored nanosized gold particles during the preparation step.

Oct 1, 2003

By H. Thomasson

THE war, like all destructive agencies, has focused attention on salvage and conservation, and to such an extent that a decade of normal progress has been crowded into a few months. This is particularly true as regards the repair of cutting tools. As a consequence, there has arisen a wide demand for comparable data by those engaged in such work, and for basic information by others who wish to repair tools. These repairs may be grouped in three classes: (1) The repair of broken tools of relatively slender cross-section, such as broaches, reamers, drills, etc., of a type that could be returned to service if a means to join the broken surfaces were available, as fortunately it is in the low-temperature silver solder process; (2) the repair of tools that possess shanks, tangs, and other non-cutting portions that may be broken or damaged to the extent that only the addition of metal will permit their return to service; and (3) the repair of special rotating tools, such as end-mills and milling cutters, that may have portions broken from the cutting edges or have their edges so worn in service as to require building up.

Jan 1, 1943

By Matthew D. Meyer

SMART, an association of surface mining companies formed in 1995 to develop a coordinated approach to technology development for the mining industry, has recognized the need for the establishment of a worldwide database that continuously collects mining equipment data and provides metrics related to productivity and cost. Under the auspices of SMART, Syncrude Canada, Suncor Energy and Albian Sands Energy (three oil sands mining operations located in northern Alberta) have established a pilot project for mine benchmarking. This presentation will include a review of the pilot progress including: ???Data gathering techniques: means of collection and storage, proposed practice for data control and normalization, access to data/reports and format for data. ???Reports/analyses for individuals, across groups, within the total industry pool and publicly. ???Security and confidentiality of information belonging to identified parties. ???Sharing of best practices among members. SMART has identified two key deliverables to ensure success of the project. First, data supplied from surface mines must be validated and normalized to common definitions and then analyzed to provide participating companies with regular reports that allow them to understand their position and resultant opportunities to achieve world-class performance. This model maintains granularity of the data for each operation that can then be recombined into standard comparisons or specific indices as required. The general categories of: operating delays, maintenance downtime, standby, and scheduled downtime, have been used to frame comparisons. Second, participating companies are looking to go behind the indices to identify and share best practices that distinguish particular operations. The spirit of cooperation between the companies involved in the pilot project is meant to be a model for future expansion of the benchmarking project.

Apr 1, 2005

By C. F. Gleeson

"Geochemical stream-sediment reconnaissance can be a useful exploration tool from the point of view of rapidly and cheaply evaluating the mineral potential of an area. This is particularly true of rugged and mountainous areas such as are found in Gaspé. For the past two years, SOQUEM has been carrying out such surveys over favorable geological regions in the Appalachians of northern New Brunswick and Gaspe. To date, about 4,000 square miles of terrain has been systematically covered by reconnaissance geochemistry. Jeeps have been used as a means of transportation in the easily accessible areas and a helicopter equipped with a winch has been used to lower crews into the more difficult-to-reach regions. Such surveys have been successful in finding metallic mineralization which otherwise might not have been detected.Electronic computation of analytical information has been used to construct regional metal maps, rolling mean maps and residual metal maps. These maps have helped in evaluating anomalies, in relating the regional geo-chemistry to the regional geology and in comparing the distribution patterns of metals. To date, some 30,000 stream-sediment samples have been collected from the Gaspe region and analyzed for Cu, Pb, Zn and Mn. These analyses are being subjected to computer analysis."

Jan 1, 1969

By A. R. Chambers

At the 1924 Annual Meeting of the Institute, held in Toronto, the writer presented some notes on the occurrence of salt at Malagash, Nova Scotia, together with a few remarks on the uses of salt. The development of these salt mines has attracted considerable attention to the district, and it may be of interest at this time to call attention to some of the newer uses of salt, and to give a brief account of the genesis of the Maritime salines, As it is not proposed to treat the subject in technical detail, and the paper is written in a lighter vein than is usual in contributions to your Transactions, you will please overlook any variations from a strictly technical method of presentation. The world's supply of salt is obtained in three principal ways: (1) By flooding shallow areas, or pans, with sea water, allowing the water to evaporate naturally by the heat of the sun's rays, and collecting the residue of solid salt. This method is employed, for example, at Turks Island, B.W.I. (2) By mining the rock salt in its natural state, and preparing it for market by a grinding process. This is the method adopted at Malagash, which is the only place in Canada where salt is actually mined. (3) By drilling a hole into an underground salt deposit, forcing fresh water clown the hole, and, after it has become saturated with salt, pumping the brine to the surface and recovering the salt by evaporation. This is the method pursued by the Canadian Salt Company, the Dominion Salt Company, and other producers in Ontario.

Jan 1, 1929

By Michael Boyle, John Zeni

"The Blind shaft boring method is a mechanised process of excavating large diameter vertical shafts downward from the surface. It is a rotary drilling technique eliminating any requirement for personnel to enter the shaft or access underground workings during drilling and lining phases. Excavated material is delivered to surface carried by a flow of circulating fluid through the centre of drill rods. The drill assembly is suspended from a large A-frame rig and powerful winch at ground level providing vertical thrust to a hard rock cutter head. INTRODUCTION The Southern Coalfields Ventilation Shaft was constructed at a mine, 45 km north-west of Wollongong. The 5 m finished diameter (6.2 m drilled) shaft reaches a final drilled depth of 517 m, the deepest, fully lined blind bored vent shaft to date in Australia. Operated by a mining company in the Southern Coalfields, the expanding mine required a new ventilation shaft and associated surface infrastructure to service future operations. An assessment of future ventilation requirements for the coal seam operations identified a need to improve the capacity and reliability of the existing underground ventilation system in order to ensure a safe and efficient underground working environment. Installation of the new upcast ventilation shaft was determined to be the most cost effective and reliable solution to provide adequate ventilation for underground operations. The completed shaft is smooth and fully lined with steel/concrete composite liners that are hydrostatically sealed. The shaft lining is designed to meet the mine ventilation requirements for a service life of 20 years. The shaft intersects the top of the working section of the coal seam at approximately 513 m of depth. This includes the shaft collar depth and shaft bottom profiled intake section.PROJECT METHODOLOGY AND INDUSTRY BEST PRACTICE The shaft was drilled using the blind bore method, an innovative construction technique and an alternative to the traditional methods of sinking deep and large diameter shafts, such as raise boring and conventional drill and blast shaft sinking. The blind bore method allows the shaft to be drilled from the surface down without anyone having to enter the shaft or the mine during the construction process. This is by far the safest method of shaft construction and is especially suitable for difficult ground conditions where there may be unstable or water-charged strata. As this method involves drilling from the surface downward, shafts can be completed ahead of the underground mine development. Thus, allowing underground operations to focus on development and production without the conflicts of managing ventilation priority for underground contractors and mucking out spoil from excavation workings."

Jan 1, 2019

By M. Hames, K. Larmour-Ship, B. Grinbaum, E. Buchalter, R. Hackl, B. Wassink

Sodium cyanide continues to be the lixiviant of choice for gold dissolution. Many gold ore-bodies contain a significant amount of cyanide-soluble copper which increases the cost of processing due to high cyanide consumption and high cyanide destruction and disposal costs. Several cyanide destruction processes are in use today, however, there are just a few cyanide recovery plants operating. A solvent extraction process to recover cyanide has been developed which utilizes the organophosphorous extractants Cyanex 923, di-butyl-butyl-phosphonate (DBBP) or tri-n-butyl phosphate (TBP) in Bateman Pulsed Columns. Copper cyanide species are first converted to hydrogen cyanide (HCN) by acidification, with or without sulfide addition. HCN is extracted by the organic and stripped using a suitable base (eg. NaOH) resulting in a high strength cyanide solution (eg. NaCN) for recycle to the gold recovery process. Continuous pilot plant testwork on HCN extraction using a 40 mm diameter Bateman Pulsed Column demonstrated a cyanide recovery of greater than 99% with final levels of cyanide in solution of less than 10 ppm. These results illustrate the potential of this technology to recycle cyanide and to detoxify final effluent streams.

Jan 1, 2005