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By X. J. Luo, F. Zhang

"Metallurgical slag (MS) such as steel slag, copper slag is a renewable resource and its compressive strength exceeds 200MPa in general. Because pure metal slug can easily be mixed into MS, complex recycle system is necessary in order to realize MS’s recycling. Meanwhile, there is high equipment failure rate in conventional crushing system. New crushing systems with inertial cone crusher could solve this problem very well. Recovery rate of MS tailings requires that crushing product can’t contain too much oversize product, so the essential equipment include two crushers and one sieve in the traditional crushing system. The new crushing system which only includes two crushers can meet the requirement and simplify the crush process. Investment of crushing equipment and infrastructure can be cut down. Operating and maintenance costs can be obviously reduced due to the simple process, which also could achieve high energy saving and excellent economic efficiency.INTRODUCTIONMetallurgical Slag (MS) such as steel slag, copper slag is a typical industrial solid waste and it threatens our environment’s safe. Metallurgical enterprises must take action to settle these wastes in order to protect our environment. Because pure metal slug can easily be mixed into MS, its uniaxial compressive strength (UCS) will exceed 200Mpa. If crushing station employs traditional crushing equipment, equipment failure will be easily caused because of these pure metal slugs. Coarse crushing equipment usually adapts jaw crusher in traditional Crushing technology and rod mill will be utilized to finish the secondary and fine crushing works. And the same time screening machinery should be used to ensure the suitable particle size (Figure 1)."

Jan 1, 2016

By R. W. Guill

"The Apex Mine is currently scheduled to be brought back into production by Hecla in the first quarter of1990. Its projected productivity rate will be exceptionally high for a small underhand cut and fill mine.The ore mined at the Apex Mine occurs within a pipe-like structure as a series of iron oxides containing both gallium and germanium, plus significant amounts of silver, zinc, lead, and copper.Ground conditions in and around the ore zone have dictated that unique approaches be utilized. To date, these have included a prototype 0.5 cu. yd diesel LHD, and the use of fibrous shotcrete in 4ft by 7ft headings, and the first pneumatically-placed cemented backfill in North America. Above all else, it is the combination of new technologies with a small and dedicated workforce which has allowed for the successful development of this ore body.IntroductionThe Apex Mine is an example of the typical small underground project. It has high grade, but low tonnage and is deposited in poor ground. In such cases, conventional planning and thinking generally results in an uneconomical evaluation and negative production decision. Fortunately, some unconventional thinking was allowed to take place during the planning and evolution of the Apex Mine development. The result now serves as an example of how such unconventional thinking can lead to the type of innovations described below.The job necessitated the development and use of new equipment and materials to execute a highly flexible underhand cut and fill mine design/pneumatic backfill concept, that must be constantly modified as different than assumed conditions become evident in and around the ore zone."

Jan 1, 1990

By R. B. Casault, J. D. Boyd, D. R. Bell

"Full-scale sections of three different types of Grade 483 line pipe have been evaluated extensively. The variations in chemical composition, optical microstructure, tensile properties, hardness and Charpy impact toughness with specimen orientation and location were determined. Significant variations in several properties, notably Charpy shelf energy, impact transition temperature, inclusion content and ferrite grain size, were observed for different locations in the pipes. The results indicate that current specifications call for test samples for the most conservative locations, except for impact tests. Minimum Charpy impact values generally occur at the II2-width location, which may be a more appropriate specified test location than the present I/4-width location. The anisotropy of impact toughness, and the importance of low sulphur content and inclusion shape control for adequate toughness in the transverse/rolling-direction orientation were demonstrated. The orientation of impact specimens is critical for spiral-weld pipe, and the current specification test is non-conservative in that it can give results which are two to three times higher than the minimum value for the steel.IntroductionThis report presents the results of an extensive metallurgical evaluation of three different Grade 483 line-pipe steels. The sample material came from full-scale sections of line pipe, which represented current commercial practice at the time of manufacture (1975-1977). Since then, significant improvements have been made in the manufacturers' procedures for producing skelp and pipe, and the line-pipe specifications have been revised. Hence, the information in this report is dated in terms of current design, but it is unique and significant in several respects:"

Jan 1, 1982

By Robert Lee

"International competition is presenting the Canadian steel industry with a major challenge. While Canadian companies have invested in new technology, research and development, activity by Canadian industry, in general, lags significantly behind that of its major competitors. While OECD countries increased their research and development spending during the 1980s, Canada's R&D funding levels have changed little since the early 1970s and have actually dropped since 1986, despite greater public discussion on the issue. This fact is reflected in the relatively slower pace of innovation in the Canadian steel industry, despite the efforts of both government and industry.In addition, there are a number of factors that undermine the competitiveness of the Canadian steel industry, in particular in relation to the United States. Among these are higher interest rates, labour costs and tax rates, as well as an overvalued Canadian dollar. Canadian steel companies are thus feeling the full impact of the current economic recession. This recession, combined with recent strikes, have, for example, caused serious losses for Algoma and Stelco.In spite of these objective difficulties, the Canadian steel industry has been able to survive and continues to strive for a leadership position in the world market. Since World War II, heavy investment in new technology has allowed the industry to upgrade its facilities and increase productivity, while at the same time improving quality and reducing pollution. This last point is particularly important in view of public insistence on improvements to the quality of the environment. Over the next decade, this technological innovation must be maintained and intensified if industry is to meet the challenge of international competition and attain a leadership position."

Jan 1, 1991

By H. Kuno, H. Kobayakawa

A borehole inclinometer with FBG optical fiber sensors has been developed to clarify very slow slope movements, and the results of its application to a real slope have been shown. The main characteristics kept in mind while developing this inclinometer are as follows. Firstly, the workability must be good so that only one cable is required for taking the measurements, because the inclinometer is composed of several FBG sensor elements constructed on an optical fiber. Secondly, the minimum interval of the distorted measurements must be close, namely, within 100 mm. Thirdly, the inclinometer must excel in thunder resistance. The measurements were executed by setting up the developed borehole inclinometer on a slope where the rate of displacement is several millimeters per year. The movement of the device was developed by comparing it with that of the results of an existing borehole inclinometer. The area of the displacement concentration, 1 m in width for 4-m sections, was confirmed by the existing borehole inclinometer. The boring core, recovered using a high-quality drilling technique, was examined. Landslide clay was not permitted at the location where the displacement had concentrated as a result of comparing the measurement results with the boring core, and the rotation of gravel by the movement of the slope’s land block was allowed. These results show the slope being caught in the stage just before a primary landslide. In addition, the feature whereby the slope behavior depends on the depth was analyzed by comparing the information on the underground displacement with precipitation and earthquake records.

Jan 1, 2015

By A. Piche, J. Nantel

"This paper describes the recent developments in Canada toward the establishment of a Canadian Centre for Mining Automation and Robotics, at McGill University and École Polytechnique in Montreal. The role of the Mining Association of Canada (MA C) and of the National Advisory Committee on Mining Automation will also be reviewed. IntroductionIn order to remain competitive, the mining industry must increase its productivity and reduce its costs. In the last two decades, this objective has been achieved through mechanization. From now on, any further improvement in productivity will be gained through increasingly more automated mining equipment.Recent international developments following the Versailles Economic Summit in June 1982, having given rise in Canada, to a renewed interest in applications of robotics and automation to mining.The mineral industry in Canada is at a crossroads. Competition in emerging from everywhere: lower grade ore bodies, increasing distances between viable mines and markets, third world massive production of certain commodities, substitution of "" space age"" materials (ceramics, plastics, composites, etc.) for metals.On the positive side, it is generally believed that present mineral commodities, i.e. base metal, gold, iron, industrial mineral s, etc ., will continue to be in high demand for centuries to come despite substitution. New applications for conventional metals will be found and the enhancement of certain properties of these conventional metals mean continued demand. For some mineral commodities, there will never exist an y substitute."

Jan 1, 1988

By Robert B. Parsons

"Canada doesn't really have a tax system for mining - it has eleven separate tax systems! The consequent maze adds some undefinable margin of difficulty to making investment decisions in Canada. But, this 11U1Ze is not likely to be simplified. Solution: learn it and sell it! Intricate Network of Winding PathwaysWebster's New World Dictionary defines the word ""maze"" as follows: ""a confusing, intricate network of winding pathways; labyrinth ... a state of confusion or bewilderment"". Webster's does not go on to give an example of a maze, but the dictionary could easily have referred to the taxation of a Canadian mining operation. The uninitiated would almost certainly look upon such taxation as a maze of the most perplexing sort.Twenty years ago, Canada's tax system was really quite simple. It is true that Canadian mining profits were subject to three levels of taxation (federal income tax, provincial income tax, and provincial mining tax), but this didn't pose a problem. Prior to 1974, at least the provincial income tax systems were somewhat the same in terms of rules .and rates, and even the provincial mining tax systems resembled one another. Mining profits were subject to pretty much the same rules, no matter what province or territory hosted the mine. Those were the “good old days” one could even dare to generalize about tax rates without fear of being labelled an imbecile!"

Jan 1, 1994

By James F. Archibald

Testing has been accomplished to substantiate recent laboratory trials which have demonstrated that thin liner membranes, applied to rock core samples, can significantly enhance the structural performance of such rock materials. A range of Canadian polymer liner materials (MineguardTM, RockguardTM and RockWebTM) have been tested side-by-side to evaluate strength and other physical property improvements generated for two highly homogeneous, though differently sourced, granodioritic rock materials. Tests were conducted on physically similar core materials, utilizing 104 to 113 samples of each respective rock type. For both rock sample populations, cores were coated using linings at thicknesses varying between 1 and 7.3 mm, typical of the application range currently used underground by mines contemplating use of such membrane agents. Results of rock failure tests, following application of passive lining covers upon the very large sample populations of each rock type, have indicated that noticeable strength improvement and enhancement of post-yield failure characteristics can be developed by the entire range of spray-on liner materials evaluated. It is shown that all of the tested liner agent materials currently available can and do act to positively reinforce rock support capabilities of modeled core pillars. Where liner materials can be effectively placed underground, it is anticipated that they may provide similar benefit and be successfully used in partial replacement for either screen or shotcrete to provide advantageous area support for rock.

May 1, 2001

By Robert M. Hopkins, Craig C. Monahan

A corrosion survey was performed on ten selected H-piles which support a reinforced concrete wharf located at Trepassey, Newfoundland. Approximately 900 thickness measurements were taken at twelve different locations in each off our zones on the steel piles: the splash (atmospheric) zone, the intertidal zone, the low tide zone and the submerged zone. Results show that over the 2o-year life of the wharf, corrosion has been most severe in the splash, low tide and submerged zones with average corrosion rates for the flanges of 6.95, 9.45 and 6.86 mils per year (mpy}, respectively, and average corrosion rates for the webs of 5.13, 4.12 and 3.45 mpy, respectively. Minimal attack was found in the intertidal zone where the average corrosion rate was only 1.66 mpy on the flanges and 1.37 mpy on the webs. Such a pattern of attack is frequently observed f or steel piles partly submerged in seawater. The abnormally low corrosion rate associated with the intertidal zone is generally explained as being due to cathodic protection induced by the high corrosion rate in the adjacent low tide zone. Analysis of the corrosion data obtained for the Trepassey wharf would suggest that this explanation might be incorrect. An alternate hypothesis has been brought forward which better accounts for the extremely low corrosion rate observed in the intertidal zones of these piles.

Jan 1, 1990

By C. J. Rockingham

"A comparative study of sulphide textures has been carried out on samples from four Archean copper-zinc massive base metal sulphide deposits: Kidd Creek, Ontario; Lake Dufault -Norbec, Quebec; Hood River-41, N. W. T.; and Geco, Ontario. These deposits have undergone metamorphic recrystallization under a range of conditions, and results of this study indicate that certain sulphide textures may be used as qualitative indicators of metamorphic grade, whereas other cannot.The sulphide textures of most value in this regard are sulphide grain sizes, which increase with increasing metamorphic grade, and the presence or absence of sedimentary/diagenetic textures, which are destroyed at the lower amphibolite facies of metamorphism. Chalcopyrite and pyrrhotite intergrowths in sphalerite increase in size, in degree of coalescence and in the ratio of unmixed pyrrhotite to chalcopyrite inclusions with increasing metamorphic rank. With increased metamorphic grade, the pyrrhotite intergrowths change from rounded inclusions on grain boundaries to rod-like shapes along sphalerite twin planes. There is also a general increase in the relative proportion of pyrrhotite in the deposits. Textures that appear to have little value as indicators of metamorphic grade are sulphide deformation textures, and triple junction point angles and their standard deviations, which show little variation from the lower greenschist to the upper amphibolite facies of metamorphism. The presence or absence of myrmekite-like magnetite also has little value in determining the relative metamorphic history of these deposits, as it is a product of local contact metamorphism."

Jan 1, 1980

By Tony Breuer

Can international development NGOs and the mining industry find common ground and work together in the Third World? The Canadian Hunger Foundation/PARTNERS in Rural Development (CHF-PARTNERS) has, over the past forty years, implemented more than 800 rural community development projects in some 38 countries of Africa, Asia, and the Americas. Working with or for the Canadian mining industry offers both opportunities and risks. We can help a mining company ensure that the workers, their families and communities share adequately in the economic and social rewards from a mining operation in their area. We can contribute to the provision of sustainable livelihoods when an operation winds down. The company?s reputation as a good corporate citizen can be enhanced. On the other hand, mining companies and NGOs have generally very different values and missions. The risk of misunderstandings from conflicting motives and work practices is correspondingly high. Both partners must state their values and expectations clearly at the start of collaboration. The NGO must ensure that the company abides by acceptable ethical standards. It must not directly or indirectly subsidize a private company from its charitable donations. The mining company must satisfy itself that the NGO has the capacity, resources and experience to produce the results expected.

May 1, 2001

Current AG and SAG mill circuits have continued the trend to larger, fewer mills. These large mills place a significant additional load on the discharge systems and it has become imperative that the designs of these mill discharge systems are evaluated carefully to ensure maximum efficiency and have the capacity to be able to handle the increased mill discharge volumes. The current generation of multiphysics modeling tools allow a detailed analysis of AG and SAG mill discharge performance. The combination of Discrete Element Method modeling and Computational Fluid Dynamics allows the designer to model in detail all aspects of a mill discharge performance. This includes a detailed description of the build-up of solids and slurry in a mill discharge, the recycle of material back into the mill through the grates, the relative wear rates and the occurrence of overloading at the pinch points. These tools allow intelligent decisions to be made regarding the type of discharge arrangement, pan lifter geometry, and discharge cone design, so as to ensure that the discharge is capable of handling the duties required for a specific installation. This paper details the current state of the art in these modeling tools, and provides an overview of some recent applications.

Jan 1, 2012

By R. W. Allgood

"THE world-wide shortage of elemental sulphur, which became sharply apparent in 1950, has focused attention on the commercial exploitation of sulphur-bearing materials such as pyritic ores, sour natural gas, and smelter gases. Although there •are no known commercial deposits of elemental sulphur in Canada, there are vast quantities of these sulphur-bearing materials. The International Nickel Company of Canada and Canadian Industries Limited have for many years collaborated in an effort to develop economic processes for the recovery of sulphur from the smelter gas arising from Inco's metallurgical operation at Copper Cliff, Ontario. While sulphuric acid has been •produced at Copper Cliff for over twenty years, recent developments will result in a 60 per cent increase in acid production early in 1952 and, later in the year, in commencement of the operation of the largest single unit ever erected for the manufacture of liquid sulphur dioxide.The purpose of this paper is to discuss •briefly the general factors associated with the recovery of sulphur from the Copper Cliff smelter gases and to describe the sulphuric acid operations and the liquid sulphur dioxide development.Processes for the manufacture of elemental sulphur, liquid sulphur dioxide, and sulphuric acid from sulphur-dioxide-bearing smelter gases are well known and in some cases •highly developed."

Jan 1, 1952

By L. K. Daneshmend

"Competitive pressures dictate that the mining industry moves to larger mobile underground haulage equipment with more advanced equipment mechanization, higher levels of autonomous operation of machines, and longer periods between access by maintenance personnel. Since such new machines will of necessity be more complex than existing designs, machine reliability has become a key issue in progressing toward advanced mobile underground haulage equipment. Reliability and maintainability models of such equipment are practically non-existent in the literature. This paper addresses the issue of reliability and maintainability of mobile underground haulage equipment on two fronts: reliability modelling to enhance decision making for maintenance planning; and reliability simulation to enable evaluation of more rigorous production planning scenarios. A case study from a gold mine in the Chilean Andes is presented, for which reliability models of mobile underground haulage equipment, specifically load-hauldump vehicles and underground haul trucks, are developed, and a reliability-based simulation implemented. IntroductionMaintenance accounts for 20% to 35% of the overall operating budget for a typical underground operation, and hence represents the largest portion of the mine’s controllable operating costs (Cutifani et al., 1996; Campbell, 1997; Goddard, 1998). This, coupled with the fact that industry today is faced with an ever more complex and demanding marketplace, has led to an increasing interest in methods to reduce maintenance costs.Although significant effort has gone into developing effective maintenance strategies for industry in general, application of these to the"

Jan 1, 2003

By E. C. Grunsky, B. W. Smee

"The development of low-cost, rapid multielement analytical techniques has generated large geochemical databases in many exploration programs. When a sampling program consists of several thousand samples, the resulting data matrix is enormous and effective interpretation using all of the elements individually becomes burdensome. However, the application of multivariate statistical techniques can extract geochemical patterns related to the underlying geology, weathering, alteration and mineralization. Imaging the results over topography enhances the interpretation of these patterns. Examples of this approach are shown from mineral exploration programs in Canada and Mexico. IntroductionThere has been a dramatic change in the effectiveness of using geochemical survey data in the past ten years. This is mostly due to:• lower cost of geochemical analysis;• lower detection limits;• new methods of multi-element analysis;• a marked decrease in the turnaround time;and• the intelligent use of computers in presenting geochemical data.Geochemical surveys commonly have two objectives: locating abnormal concentrations of ore-forming or pathfinder elements and characterizing the underlying host lithologies. Geochemical surveys often employ a wide range of sample media that may typically include whole rock lithogeochemistry, various soil horizons, till and basal till sampling, stream sediments, lake sediments, and various forms of weathered regolith. Each of these sample media will exhibit a unique element distribution that must be factored in the interpretation phase of a geochemical survey study. This can become a cumbersome process if univariate data handling methods are employed."

Jan 1, 2003

By Turgut Yalcin

"High-grade concentrates are achieved in flotation columns primarily due to the use of thick froth layers and wash water, both of which facilitate the drainage of hydrophilic minerals from the froth. However, conventional columns employ tall, non-agitated recovery sections for bubble-particle attachment that require high headroom and special gas spargers as well as imposing particle size limitations. These disadvantages can be all alleviated by carrying out the recovery part of the process in a mechanical or pneumatic cell which generate froth more conveniently and efficiently.This paper describes the combining of mechanical and column flotation in a single unit and discusses the influence of various parameters on the performance of the system.INTRODUCTIONIn a flotation process, some of the minerals lifted up to the froth phase may drain back to the pulp due to various reasons such as weak attachment of particles to air bubbles, bursting of air bubbles, agitation of froth, etc. Weakly floating and entrained hydrophilic minerals drain at a faster rate than the strongly floating minerals, and effective exploitation of such differential drainage can lead to cleaner concentrates.For a given mineral, if the rate of flotation from pulp to froth is k1 (min·1) and the rate of drainage from froth to pulp is k2 (min""1), then the net (overall) flotation rate of the mineral, k (min-1 ), will be [Lynch et al., 1981 ]:"

Jan 1, 1997

By Robert B. Parsons

"The Department of Finance introduced draft amendments to the resource allowance regulations on July 23, 1992 that effectively nullify the decision in the Gulf Canada Limited case. Prior to the amendments it appeared that only ""directly"" related general and administrative, capital cost allowance and scientific research expenditures had to be deducted from resource profits. Now ancillary expenditures are required to be deducted. Consequently, the ability of taxpayers to claim the resource allowance is curtailed.IntroductionOn October 25, 1990 it was almost certain that taxable mines were going to get a break. The Federal Court-Trial Division had just decided in Gulf Canada Limited's favour to allow it to claim resource related tax benefits larger than what Revenue Canada evidently wished. Revenue Canada appealed first to the Federal Court of Appeal and then to the Supreme Court of Canada. On January 10, 1992 the Federal Court of Appeal agreed with the Federal Court decision and on July 2, 1992the Supreme Court declined to hear any further appeal. A mere three weeks later, on July 23, 1992, the Department of Finance issued draft ""clarifying"" measures to amend the calculation of the resource allowance. These measures effectively nullify the benefits that arose under the decisions of the Federal Court."

Jan 1, 1992

By J. W. Scott, G. G. R. Falkenberg

"The Syncrude project is an integrated complex designed to mine, extract and upgrade bitumen from the Athabasca tar sands to produce 129,000 barrels per day of synthetic crude oil. This paper provides a brief general description of the location, history and geology of the tar sands and the overall organization and structure of the project. The major emphasis and the bulk of the detail presented deals with the extraction plant; a material handling and mineral processing installation designed to treat 312,000 tons per day of tar sand feed.History of the Tar SandsThe Athabasca tar sand deposit was recorded in 1788 by Peter Pond, however the first serious geological mapping and exploration did not begin until 1915. Little interest was taken in the deposits until the Second World War, when the governments of Canada and Alberta conducted an extensive exploration program. In addition a number of pilot plants were sponsored during the 1940 -1950 decade. The hot water separation process was successfully demonstrated on the pilot plant scale during 1948 -49, and was established commercially in 1967 in the G.C.O.S. plant. The Syncrude plant, due to come on stream in April 1978, also employs the hot water separation process."

Jan 1, 1978

"INTRODUCTIONThe Department of Energy, Mines and Resources has recently developed two automatic controls for use in the cyanidation circuits of Canadian gold mills. These controls are the alkalinity probe and the Continuous Cyanide Titrator both of which are discussed in the paper ""Instrumentation in the Cyanide Process"".(1)In May 1966 these process controls and associated recording equipment were installed in the Bralorne mill by two Scientific Officers from the Department. The object was to determine if the equipment was amenable and applicable to this particular circuit. The purpose of this paper is to discuss the performance of the equipment over a test period of 4 months.CONCLUSIONSThe results of test work to date indicates that both the Conductivity Probe and the Continuous Cyanide Titrator would be an as set to the operation of the Bralorne mill.The conclusions are generalized as follows:-(1) At a milling rate of 100, 000 tons per year the expected reductionin reagent consumption would give a direct saving of 37, 660 lbs of lime@$0.030 per lb and 15, 790 lbs of sodium cyanide@ $0.175 per lb. Such cost savings would pay for the equipment and installation costs within a 30 month period"

Jan 1, 1967

By Kristie D. Tarr

Ideally, in situ monitoring would supply the input data for numerical modeling of backfill material property requirements. However, clue to production requirements and costs of conducting field tests, input data are often based on small-scale laboratory tests. The size of test samples is known to play an important role in the laboratory assessment of the behaviour of geotechnical materials, including backfill. There are observed differences between the mechanical properties of laboratory-scale samples and those of in situ materials, and these are generally attributed to the differences in scale. Various scaling factors have been proposed for converting laboratory observations to anticipated in situ conditions for soil and rock materials. With regard to mine backfill, very limited studies exist which have involved the effects of sample size on material properties. The literature indicates that reported backfill strength data are based on a variety of test sample sizes and in some cases, specimen geometries. Carefully determined laboratory scale effects could play an important role in estimating the potential backfill behaviour in the field, especially when developing new backfill systems. Laboratory studies were conducted with sample diameters ranging from 50 to 300 mm. Scale factors relating specimen size to strength were developed wherever possible, and are presented in this paper

May 1, 2008