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By M. Boodman, E. Gertner

"At first glance, the activities related to mining and mineral exploration appear to be local or domestic, rather than international, in nature. Minerals, as corporeal or tangible property, form an integral part of the land in which they are found until extracted and exploited commercially. Even in the latter phase, the tangible nature of minerals gives the impression that the law governing the commercialization of minerals is the law of their situs at any given time. The nature of minerals appears to negate the international aspect of mineral enterprises.The fundamental flaw in the above analysis is its focus upon the nature of minerals, rather than the role of persons in mineral enterprises. The high costs of mineral exploration and commercialization invariably require the involvement of international consortiums or joint ventures. Governments may not have access to the funds necessary to exploit the mineral resources that they control. Local or domestic enterprises may not have sufficient expertise for mineral exploration. Further, markets for various types of minerals are far from localized or static. For these and other reasons, the tangible and localized nature of minerals belies the fundamentally international nature of mineral exploration and commercialization."

Jan 1, 2004

By R. E. Jones

"Crusher sizing and application in mining operations is the selection of a crusher or a series of crushers to reduce run of mine ore to a size suitable for either autogenous or conventional grinding. It is important that the crusher or crushers be sized to operate within the range to which they have been designed. By the range to which they have been designed, we mean that the reduction ration must be held between specified limits. Reduction ration is the relationship between feed size to product size.In todays plants reduction is usually accomplished in three stages by primary, secondary and tertiary crushers.Primary crushers are either jaw or gyratory and are designed to handle run of mine feed at an open side setting of 5-1/2” to 7”. Reduction ration should not exceed 7 to 1.Jaw CrushersThe model size of a jaw crusher signifies the feed opening. A model 60 x48 jaw has a feed opening 60” wide by 48” long. The 48” is the dimension between the top of the swing jaw and the top of the stationary jaw. The 60” is the width between the two side frames. The crusher open side setting is the discharge opening at the bottom of the crushing chamber with the jaws in an open position. When corrugated jaw plates are used, the open side setting is measured from tip of one jaw plate to the valley of the opposite jaw plate. If a jaw crusher has a 6” open side setting with a 1” jaw motion, you could also say it has a 5” closed side setting."

Jan 1, 1974

By M. G. Rylatt, G. M. Popplewell

"Production from Canada's first diamond mine is planned for the last quarter of 1998. The climatic conditions and the variation in kimberlite types to be treated have lead to the development of a compact and flexible processing plant.High kimberlite moisture contents and winter temperatures below -40°C have dictated a process flowsheet with limited in-circuit storage to reduce materials handling difficulties. The latest developments in High Pressure Grinding Roll technology will be used to liberate the valuable diamond, reduce diamond breakage, and increase fines production to reduce the amount of material for down stream processing in the Heavy Medium Separation section.A varying heavy mineral concentrate yield has lead to the development of a final Recovery section that will incorporate Attrition Milling and Wet High Intensity Magnetic Separation for concentrate reduction. The latest developments in diamond X-ray sorting will be used to produce a final diamond concentrate for mechanical sizing, weighing and packing.Fine tailings thickening will utilise Deep Bed Compression type thickeners. This relatively new technology can produce;i) high underflow densities at low flocculant dosage rates, andii) clear overflowswith a smaller thickening area than conventional high-rate thickeners."

Jan 1, 1998

By C. L. O?Brian

Note: The figures quoted and used herein have been collected and furnished by the Dominion Bureau of Statistics. Without the help and willing co-operation of the officials of the Burreau, this study would not have been possible. Introductory and General Coal has one unique quality that distinguishes it from other minerals, one that is too, often forgotten. This is the quality of ubiquity. No other single mineral supplies such a wide and varied range of human requirements nor, up to the present, is there any indication of a rival in this regard. There is, consequently, reason for individual study of each of the major portions of the overall market for coa1. The provision of heat for our homes is a necessity of life in our Northern climate and the largest single source of this heat is coal. It is intended to present here a factual survey of the use ?of coal in home heating throughout Canada and the effect of these requirements upon the production of coal and the development of this phase of the mineral industry. The coals used for house heating in Canada fall into two more or less distinct classes, the very low volatile fuels such as anthracite and including coke, and the bituminous coals, including the sub-bituminous and lignite types. The bituminous coals are, of course, consumed in very large quantity by industry and the railways and are the most important type both in tonnage and in respect to the area supplied. Canada consumes annually for all purposes some 4,400,000 tons of anthracite, 4,300,000 tons of coke exclusive of Petroleum coke, and some 40,000,000 tons of bituminous coals. This is a fair measure of the relative importance to the overall economy although it will be seen later that the concentration of the household use of anthracite and coke into one area does create a considerable problem.

Jan 1, 1951

By J. W. Matousek

Tonnage oxygen plays a critical role in the primary production of two of the most important industrial metals - copper and iron - and minute quantities of oxygen play equally critical roles in determining the properties of the market products. For refined copper, oxygen in the final metal is balanced between maximizing electrical conductivity, neutralizing the effects of harmful impurities, and ensuring that the metal takes on the desired "set" during casting - the surface texture and physical properties required for subsequent rolling and drawing. For refined iron, oxygen must be removed to minimize reaction with carbon during cooling from the molten state with the generation of CO and CO2 - leading to a loss of carbon and the creation of "blow-holes" in the solid ingots and the potential for defects in rolled and forged products. This paper reviews the thermodynamics of oxygen in molten copper and iron at the levels of primary interest to production metallurgists.

Jan 1, 2014

By E. Ozberk, N. Gibson, W. G. Davenport

"In the 1950s, Canada produced more than ninety-five percent of the non-communist world's nickel and achieved dominance in terms of production, technology and pricing policies.Over the past thirty years there have been dramatic changes in the nickel industry to the extent that Canadian production is now less than thirty per cent of the total.In this document we have presented statistics relevant to this transformation and reviewed the technology, particularly with regards to energy and environmental considerations.Under the new market conditions nickel producers are likely to face more difficult competition than they have encountered in the past.The economic scene and measured nickel reserves dictate that for the purpose of increasing production, new nickel smelters will not be built in Canada in the foreseeable future. However, in order to reduce sulphur dioxide emissions, Canadian nickel smelters will possibly go through some modifications or rebuilding.IntroductionThis paper presents a review of the Canadian nickel industry in relation to the world nickel industry. Major changes are described which have occurred in the characteristics of the nickel market over the last thirty years. The pre sent status of the nickel market with respect to Forecasting future trends is reviewed and attempts are made to predict what further changes will take place in the next two decades. Comparisons are made of the economics of producing nickel from sulphide ores and oxide ores and the advantages and disadvantages the Canadian nickel producers face.A brief critique of the existing and emerging nickel production technologies in Canada and the world is carried out and attempts are mad e to predict the changes which may take place in the foreseeable future."

Jan 1, 1983

By A. E. Wraith, R. Harris, J. Qiu, R. Parra

Small pilot scale experiments have shown that it is possible to almost fully eliminate the minor elements (ME), namely As, Sb, Bi and Pb contained in smelter dusts by vacuum calcination of mixtures of the dust with sulphidizing agents such as dirty copper concentrate or elemental sulphur at 900 °C and 80 +/- 30 Pa for 90 minutes. The products of this calcination are a residue comprising a purified mixture of copper containing compounds along with the gangue constituents and a high sulphur condensate comprising a mixture of the minor element compounds. In particular, the Cu:ME ratios of the concentrate and dust were increased from 250 and 50, from 28 and 12 and from 36 and 8 to roughly 3000, 3000 and 100 for the calcine, for Bi, As and Sb, respectively. It has also been calculated that (i) the copper content of the vacuum calcine may be recovered by feeding it into a Peirce-Smith converter during its slag blow, and (ii) the resulting recycling could increase the minor element treatment capacity of a smelter by 100 % while also reducing the blister As content by a factor of three. The experimental results are briefly discussed and a treated dust recycling option is examined. Example operating conditions are presented and available commercial technology for the vacuum calcination of the mixtures is reviewed.

Jan 1, 2007

By Jessica E. Heuchan

An industry survey has been conducted by the Queen's University Mining Engineering Department of 30 Canadian mining organizations to determine how effectively newly graduated mining engineers meet the needs of the industry. The principal objectives of the survey were to evaluate, and thus provide focus on change for, curricula being taught at Canadian mining engineering schools in service of the industry's needs; to provide feedback on current industry expectations; and to reinforce contacts with the industry as a means of providing future collaboration. A strong focus of the survey was placed upon industry's perception of the special attributes of engineering hires and applicability of student academic training to meet their industrial requirements. In providing this detailed summary of corporate responses, a clearer understanding of the mining industry's expectations of engineering training at Canadian colleges and universities has been gained.

May 1, 2003

By R. G. Zaripova, N. D. Ryan, H. J. McQueen

The austenitic and ferritic stainless steels do not undergo any phase transformation that induces very fine grains in the product through thermomechanical processing as practiced in most other steels. Considerable grain refinement can be achieved by intense multistage deformation descending through warm to cold working; notably multi-axial forging of bulk material can attain high strains with diminished risk of cracking. Hot working to improve ductility yields finer grain sizes as the T is reduced and strain rate E raised; increased strain has limited effect due to the steady state regime. Ferritic steels develop subgrains with size diminishing as E rises and T falls with the advantage of retained strain hardening; recrystallization delivers grains several times the cell size. In austenitic steels, dynamic recrystallization (DRX) provides finer grains at higher E and lower T with a lower limit due to intergranular cracking. The DRX grains contain a strengthening substructure that can easily be retained by quenching; if static recrystallization is allowed to occur the grain size rises markedly. Multistage rolling with diminishing T is able to provide grain refinement to the same degree as straining at the finishing T yet provides better ductility. grains on recrystallization. As a result of the strain induced transformation to martensite, small subzero deformations of austenitic or duplex steels produce very high dislocation densities that yield marked grain refinement when they revert upon reheating.

Jan 1, 2004

By Paul MacLean

MAC TSM ?Mining and Biodiversity Conservation 1.Corporate biodiversity conservation policy, accountability and communications 2.Facility-Level biodiversity conservation planning and implementation 3.Biodiversity conservation reporting ?Activities indicative of level AA -AAA (formerly 4-5) performance: ?Independent verification ?Integration into broader business strategy and planning processes ?Engagement with communities of interest ?Commitment to actively partner with other organisations for biodiversity conservation

May 1, 2011

By Zygmunt Wegrzyk

Poland is rich in hard and brown coal reserves, which have become the most important, and steadily developing, primary source of energy. With 192.6 mill. t of hard coal production and 40 mill. t of exports in 1978, Poland is fourth and second in the world respectively. The paper discusses the various mining methods adopted in the country's history of mining. Particular emphasis is placed on longwails, their mechanization and equipment assembled in the form of fully mechanized face complexes suited for varied geological conditions. Measures to improve the recovery ratio of coal resources are dealt with. investment efforts undertaken in the coal industry are outlined. An account is given of the ever improving techno-economic results of coal mining. The country also exports a wide range of mining equipment and transfers its well-founded technical know-how to others. There are strong cooperative links with many foreign partners.

Jan 1, 1979

By D. C. McKechnie

To the examining engineer, the ever-recurring problem involving the valuation of ore in a prospect presents at different times highly divergent aspects- some entirely physical or mathematical, others essentially personal. The majority of the problems discussed in this paper are obvious to the engineer, and need little elaboration. By the prospector and the general public, however, a number of these questions are often and completely over-looked, or else approached in such a way as to produce final results which are, to say the least, misleading and at times decidedly erroneous. While the purpose of this paper is to deal with prospects or potential mines, many of the problems considered apply equally well to mines with developed ore reserves. As the usual showings on a prospect consist chiefly of a few open-cuts and a limited amount of underground development work, an estimation of the actual ore reserves is a question of minor import, and seldom enters appreciably into an estimation of the probable value of the particular property. The physical valuation of a prospect mainly involves the consideration of such subjects as the general geological features exposed, the strength and type of mineralization, the width and persistence of any associated veins, shear zones, fractures or contact zones, together with the possible grade, size, and continuity of any ore-bodies that may there occur.

Jan 1, 1930

Electric Vehicle Controllers Ltd. ?EVC started in 1981 ?Underground electric locomotive drive systems ?Developed tandem load sharing system and radio ELOS controls ?Locomotive autonomy systems ?Entered space technology development in 1999 with NORCAT to develop Mars drill for CSA ?Commercial distributor for drilling systems, lunar physical simulants, electric mobility systems and lunar mining technologies

May 1, 2009

By Saba Gharedash

In this study the results of a series of numerical simulations which are conducted for one of the tunnels of the Mashhad metro line 2 project are presented to evaluate the role of tunnel face support pressure and soil strength parameters on deformation of tunnel lining and face deformation. To achieve this goal, comparative numerical simulations of a mechanized tunnel advance in soft non- homogeneous soil on top of the ground water table and beneath the building are conducted and sensitivity analysis is performed. Development of a step by step tunnel construction process is modeled using a three dimensional finite difference model (FLAC3D) taking into account all the relevant components of shield tunneling. In order to understand the mechanism of the effects of a variety of support pressures on face deformation and lining stresses, numerical simulations are conducted. It is found that the use of different face supports causes a considerable influence on the forces of tunnel lining. In addition, it is revealed that building weight help to change the stress paths and the stress distributions in the tunnel lining.

Aug 1, 2013

By A. J. Antony Chettupuzha

Electronic Product and Process Management [EPPM] systems provide the capability to establish and map information flow between different parties in a construction project as well as model project processes. Much of the information relating to processes and their structure, the actors that operate them, and the data associated with each instance of a process is encapsulated within workflows. The wealth of information contained in an EPPM system can be exploited to extract knowledge that can provide significant cost benefits to construction companies. Workflows provide an ideal medium for the capture of knowledge over the course of a project lifecycle. We demonstrate how this knowledge may then be used to analyze workflows and determine metrics that establish the suitability of workflows to construction processes. We present a conceptual approach to measure the performance of a workflow, its constituent components and evolution, which may be used to lay the foundation for establishing paragon workflows suited to classes of construction activities.

Aug 1, 2013

By S. R. McCutcheon

"The regional stratigraphy of the Lower Carboniferous Windsor Group in the Moncton Subbasin indicates that evaporites could be present in the Marysville Subbasin, part of what was formerly called the Central New Brunswick Platform. The Windsor Group consists of basement-fringing, algal build-ups (Gays River Formation), in places with intercalated siliciclastics (Parleeville), which are laterally equivalent to deeper-water, very thin to thinly bedded, euxinic limestone (Macumber). The Macumber is overlain by stratiform, nodular to mosaic anhydrite (Upperton) that is hosted by carbonate or calcareous siliciclastics. The sulphate also is equivalent, in part, to the algal buildups. Deep-water salts (Cassidy Lake) which overlie and in places are laterally equivalent to Upperton rocks have a basincentre distribution. The Windsor Group is overlain by shallow water evaporites and mudstones (Clover Hill) or by greenish grey mudstone (""transitional beds""). The paleogeographic distribution of these rocks provide important clues that help predict where deposits of salt and potash can occur.IntroductionCurrently there are three known potash deposits in southern New Brunswick (2, 3 and 4, in Fig. I). All three deposits occur in the Windsor Group of the Moncton Subbasin, but until recently their exact stratigraphic position within the group was not known.The Windsor Group is a cyclic sequence of carbonates, evaporites and red beds that is up to 1.0 km in thickness (Schenk 1969, p. 1038). It is Late Mississippian (Visean) in age and the type area is near Windsor, Nova Scotia. The group was named by Dawson (1873) but the rocks were described earlier by Hartt (1867). Dawson (ibid.) was the first to assign rocks in southern New Brunswick to the Windsor Group."

Jan 1, 1983

By L. W. F. Mackenzie

The influence of rolling temperature and annealing on the recrystallization and texture of magnesium AZ31 has been investigated. 100x125x6 mm AZ31 plate was cast in a permanent steel mould and then homogenized at 380°C. As-cast and homogenized microstructures were then characterized, and 35x30x6 mm specimens were machined from the homogenized material. Specimens were rolled up to 40% at temperatures between 25 and 350°C; selected specimens were subsequently annealed at 400°C. Following rolling, the microstructures were compared. The influence of rolling temperature on as-rolled texture has been demonstrated, and texture evolution has been evaluated following annealing. The recrystallization behavior has also been characterized. Optical microscopy, scanning electron microscopy and electron backscattered diffraction (EBSD) were used to characterize the microstructures of the alloys. X-ray texture analysis was used to investigate the texture in as-rolled and annealed specimens.

Jan 1, 2006

By L. Li

The backfilling of underground stopes is a common practice throughout the mining industry. The stresses imposed by the backfill on the surrounding rock mass need to be assessed because of their influence on ground stability and on the hydro-geochemical response of the fill material. There is, however, a complex interaction between the relatively soft backfill and the much stiffer adjacent rock mass. In recent years, the authors have presented results from investigations conducted on stress distributions (obtained numerically and analytically) in and around backfilled stopes with (sub)vertical walls. In this paper, the influence of stope inclination and of backfill properties is evaluated. Results indicate that, in general, the vertical and horizontal stresses in inclined stopes are close to, but somewhat smaller than the stresses in vertical stopes. Nonetheless, significant differences can be observed in some cases, especially for the vertical stress along the inclined central line and along the hanging wall. It is further shown that neglecting deformability in limit equilibrium analyses is an acceptable assumption. However, Poisson?s ratio and the dilatancy angle, usually neglected in limit equilibrium analyses, may have significant effect on the stress distribution. Results also confirm that the backfill strength parameters (cohesion and friction angle) are critical factors required to properly evaluate the stress distribution, at least within a certain range of parameter values.

May 1, 2007

By S. A. Willis

For over 150 years gypsum from Nova Scotia has been shipped via water to the United States east coast. The history of the movement has been one of continual improvements in quarrying, loading, and shipping. At the start, man-size rock quarried by hand auger and black powder was loaded into horse-drawn carts, hauled to the waterfront, and dumped into 100-ton sailing schooners. Last year the Canadian Gypsum Company completed the latest and most modern of these successive installations for the movement of this Nova Scotia product. The new system loads crushed gypsum into 11,600-ton vessels at Hantsport in two hours' time at high tide. At the head of the bay of Fundy are located vast deposits of gypsum. The tidal rise and fall of 45 feet twice a day, with its attendant swift currents, has always presented major navigation and shipping problems. When the tide is low, the Hantsport ship-loading pier is high and dry, with no water within 400 feet. Three hours later a large river has flooded in (running up hill) and large steamers can dock at the wharf. Before high water, the ship has been loaded and -there is a depth of 30 feet or more of water around the wharf. At high water, the ship sails away on the ebbing tide as the river runs in the other direction. Tides are caused by the gravitational attraction of the moon and sun on the ocean. When both celestial bodies are pulling together the 'spring tide' results, which means a 50-foot variation from high to low. This occurs at new and full moon. A week later, when the sun and moon work in opposition, the difference is only 32 feet between high and low water. The bay of Fundy, having a funnel shape (150 miles wide at mouth from Yarmouth to Portland, while the upper estuary at Hantsport is only one mile wide), builds up a tidal influence from 10 feet at the mouth to an average of 45 feet at Hantsport.

Jan 1, 1948

By Sadan Kelebek, Gerhard W. Heinrich, Peter F. Wells, Peter J. Whittaker

"Based on plant mineralogical data & circuit modelling, a pilot plant campaign was conducted at Strathcona Mill to identify options for improving the performance and operating flexibility of the copper-nickel separation circuits. Emphasis was given to options for combined treatment of the two feed streams (primary nickel ore rougher concentrate and copper ore circuit concentrate) to obtain more flexibility in the use of existing column flotation capacities. The pilot test results demonstrated that circuits which incorporated preconcentration prior to column flotation gave the best metallurgical results. Maximum column carrying rates were also related to the preconcentration. Predictions that increased circulating loads from the column scavengers would improve copper-nickel separation performance were confirmed.IntroductionThe copper-nickel separation circuits at Falconbridge's Strathcona Mill produce a high grade (>30% Cu) copper concentrate most of which is treated at the Falconbridge Kidd Creek smelter near Timmins. The remaining nickel concentrate which still contains approximately 20% of the feed copper is combined with other lower grade nickel/copper concentrates and shipped to the Falconbridge nickel smelter. The separation is required because of the limited capacity for copper processing in and downstream from the nickel smelter. Since no nickel is recovered at present in the Kidd smelter, the challenge is to minimize the nickel content of the copper concentrate.At present there are two independent separation circuits treating the rougher concentrates from the copper and nickel circuits as shown in Figure I. The minerals treated are mainly chalcopyrite and pentlandite but there is up to 25% of the copper present as cubanite in the copper ore. The circuits were kept separate because the flotation rates and froth characteristics were very different, probably because of the presence of cubanite and the large difference in the concentrate grades feeding the circuits."

Jan 1, 1995