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By R. E. Gilmore

Introduction The Sydney coal-field extends for a distance of thirty miles along the northeastern coast of Cape Breton island. At a central focal point at the tip of the south arm of Sydney harbour, seven miles or so in from the Atlantic ocean, is the city of Sydney, with Port Morien to the southeast and Sydney Mines to the north . Mining centres along the ocean coast between these points include Birchgrove, Reserve, Glace Bay, and Waterford. The field is divided into three districts or 'basins', namely, Morien basin to the south, Glace Bay in the centre, and the Lingan-Sydney Mines basin to the northeast. The eastern and western portions of the latter are known as the Lingan and the Sydney Mines basins, respectively. Six distinct coal seams are described as existing in the Morien basin, nine in the Glace Bay basin, and six in both the Lingan and the Sydney Mines basin. Although known by different names in the several basins, a definite continuity of the seams has been established.

Jan 1, 1933

By E. J. Sides

In this paper, the argument is put forth that the codes used for public reporting of mineral resources and mineral reserves have some significant limitations with regard to the information provided to investors on the short- to medium-term value of mining properties. Such limitations include a) failure to explicitly incorporate a time element and b) failure to state explicitly the quantity and quality of mineral product that will be produced for sale. A time-value framework for reporting mineral assets is proposed in order to overcome these limitations. The proposed system is based on two classification axes: a) an X-axis representing time in years during which the value of the asset is likely to be realized and b) a Y-axis representing the value identified by a mining or exploration company\u2019s activities. The potential benefits of this system are discussed, including the ability to incorporate factors, such as permitting and construction times, directly into the magnitude of the reported mineral assets. The proposed framework would assist in the standardization of mineral assets reporting in such a manner that they could eventually be more readily included in financial statements. Year of Publication: Not explicitly mentioned in the document.

Jan 1, 2010

By C. Tasker

Introduction In the Early part of 1930 the Ontario Research Foundation was asked by the Minister of Mines, the Hon. Charles McCrea, K.C., M.P.P., to undertake a technical and economic investigation of the Northern Ontario lignite deposit. This investigation has been under way since June, 1930, and has necessitated considerable work at the deposit, in the laboratories of the Foundation, and at test plants in Europe. All the work has been carried out in active co-operation with the Provincial Department of Mines, the Deputy Minister, Mr. T. F. Sutherland, and several of his technical colleagues being associated with members of the staff of the Foundation on the Advisory Committee, which has met at frequent intervals to co-ordinate and direct the various lines of research. An interim report was made to the Minister of Mines by the Director of the Foundation, Dr. H. B. Speakman, at the end of December, 1932, and is at present under consideration by the Minister. This report deals with the extent and character of the deposit, the methods and costs of mining, and the methods and costs of processing raw lignite, the characteristics of certain lignite products, and the technology and economics of present fuel utilization by railways, industry, and domestic users in northern Ontario. It is not the purpose of the author to discuss in this paper either the geology of the deposit or the economics of the mining, processing, and utilization of lignite, but rather to deal briefly with some of the technical problems investigated by the Foundation during the study of the characteristics and methods of utilization of Northern Ontario lignite. Some mention, however, of the work carried out to define the extent of the deposit is a prerequisite to any discussion of the nature of the lignite.

Jan 1, 1933

By Raymond Dallaire

The Humphrey's spiral is a static gravity separation device which cannot be adjusted to match short-term variations that occur in the feed. Any disturbance in the feed grade, per cent solids or flow rate affects substantially the recovery and grade of concentrate. Such variations must be minimized in order to maintain the desired rate of production and quality of the product for which the installation has been designed. A study has been performed in which the foregoing assertions were quantified. The feed grade, per cent solids, flow rate and particle size were varied independently. Ore from Carol Lake, Nfld., was used throughout the experiments. This consisted of specular hematite and magnetite in a silica gangue.

Jan 1, 1978

By V. Falmagne

The mining sequence at Noranda?s Bell-Allard mine calls for two mining fronts retreating toward a central pillar known as the Retreat Zone between pyramids A and C. It is clear from numerical modelling and rock mass characterization that the induced stress level in the pillar will exceed the rock mass capacity. A mining plan was developed including the re-dimensioning of stopes in the Retreat Zone, additional ground support and instrumentation in order to ensure the safety of the workforce and to maximize ore recovery while minimizing production delays. The mining strategy consists in allowing the rock mass to fracture and fail progressively while maintaining control of the existing openings with the appropriate support. A systematic analysis of rockbursting and caving hazards was conducted for all accesses and stopes in order to plan ground support and instrumentation needs.

Apr 1, 2004

By Y. F. Jiang, K. Fang, Q. Q. Jiang, Q. Wu

Inter formational sliding of bedding planes between two different rock types in Badong formation is an important reason that leads to the instability and fracture of rock mass in this stratum. There are no specific research achievements on bedding planes between two different rock types in Badong formation. In order to study the shear mechanical properties of bedding planes between two different rock types. This paper using the software of particle flow code (PFC) and JRC model to establish several typical structures of different roughness coefficient of surface morphology based on the laboratory tests on silty mudstone and marlite in Badong formation. A great deal of numerical shear tests were carried out by ball production, radius expansion and servo infliction. The research results are as follows: First, shear strength of Badong formation is found to vary between that of silty mudstone and marlite isotropic planes by analyzing shear strength of the homogenous bedding planes and inhomogeneous rock types, we can find that the shearing strength in Badong formation is between silty mudstone and marlite isotropic planes and which is closer to the shearing strength of silty mudstone isotropic planes. Second, the basical friction angle of bedding planes between two different rock types in Badong formation is between silty mudstone and marlite isotropic planes and which is closer to the basical friction angle of silty mudstone between isotropic planes. Third, based on the experimental results, an expression is obtained to describe the relationship of the ratio of shearing strength between bedding planes of two different rock types and isotropic planes in soft rock, the rock combination coefficient, and the roughness coefficient. This study has important significance for further research on the shear mechanical properties of bedding planes between two different rock types.

Jan 1, 2015

By Charles Camsell

THE Northwest Territories covers a very large area-more than one-third of all Canada-and its most northern point, Cape Columbia in Ellesmere island, is distant only 500 miles from the Pole. Our first knowledge of the Arctic Archipelago, of which Ellesmere island forms a part, resulted from a gold-mining venture in Queen Elizabeth's reign. The English navigators of that time were eager to find a north-westerly and shorter and Jess hazardous route to the riches of China and Japan than that which Magellan had discovered, but they were unaware that the continent then known to bar a direct route extended in great width far to the north. Frobisher was one of these navigators. He reached in 1576 the bay in Baffin island now named after him, convinced that he had found a passage connecting the Atlantic with Asiatic seas. Forced to re-turn after ordeals in which ice, wind, and Eskimos flayed formidable parts, he brought back, among other novelties, a piece o black stone which had been picked up casually by one of his officers, and gave a little of it to the wife of one of the venturers, or financial backers of the enterprise. To quote now from Hakluyt: ? 'She by chance threw and burned it in the fire so long that , at length being taken forth and quenched in a little vinegar, it glistered with a bright marquesset of gold. Whereupon the matter being called in sorne question, it was brought to certain goldminers in London to make assay thereof, who indeed found it to hold gold and that very richly for the quantity." On the strength of this, the venturers, anticipating much profit, launched a second expedition to secure more of this stone, and 143 persons, including 14 miners and finers, set forth in 1577 and returned the same year, with, however, 200 tons of another mineral. Influenced by glowing accounts of veritable mountains of this mineral and by assays made after "additaments"-that is how "salting" in those days was described-the venturers, including Elizabeth, supplied funds for erecting a smelter and refinery at Dartford and outfitting a stilllarger expedition. And so, in 1578, fifteen ships departed with the Queen's blessing, for the same remote shores. After many mishaps, they returned with over 1,000 tons of the mineral, but when it yielded very little of value at the works in Dartford, the? Company of Venturers was forced into liquidation. Though our first prospector and miner was rather inconsiderate of the investors, he proved the existence of an archipelago, hitherto unknown, and secured much information about the new land and its dwellers.

Jan 1, 1938

By L. Gutierrez, M. Pawlik

The rheology artificial mixtures of bitumen with fine quartz of varying bitumen content, as well as actual oil sand ores, was investigated under different physicochemical conditions (pH, temperature). All rheological measurements were conducted using a Haake Rotovisco VT550 rotational viscometer, connected to a fixture specifically designed to measure properties of settling suspensions. It was found that at low bitumen contents (1 %, wt.) the pH of the slurries was the most important parameter that controlled the rheology of quartz-bitumen slurries. At higher bitumen contents (10%, wt.), it was a combination of high temperature and high pH that gave the lowest apparent viscosities and yield stresses of the model mixtures. These model observations correlated well with the rheology data obtained for slurries of actual oil sand ores. The overall results were discussed in terms of aggregation-dispersion phenomena between bitumen and mineral particles.

Jan 1, 2009

By Adam Moore, Ryan Gillespie, Jarrett Quinn, Audrey Walters, Peter Radziszewski

"Vale Long Harbour Processing Plant (LHPP) was designed to process Voisey’s Bay nickel concentrate into finished nickel and associated copper and cobalt products. The plant includes a secondary grinding circuit comprising two Stirred Media Detritors (SMDs) operating in parallel. The ultrafine grinding circuit was designed to process concentrate at a rate of 33 t/h and produce a ground product (P80) of 20 µm to feed the leach circuits. Start-up of the grinding circuit at LHPP was undertaken in December 2014.The objective of this paper will be to describe the design, commissioning, start-up and performance of the secondary grinding circuit with a focus on the two Metso SMD-355-C mills. Following a brief overview of Vale’s LHPP and the SMD technology, the paper will review the design of the SMD secondary grinding circuit from lab tests through to scale-up performance prediction. This will be followed by the results of circuit commissioning outlining some of the issues raised and addressed after which SMD performance will be outlined. Specifically, the SMD circuit grinding performance will be examined since start-up which will include the effect of media size and wear on grinding. Furthermore, impeller wear will be examined by determining initial “shear volume” and worn “shear volume” as well as its effect on mill power and the means to maintain it. The paper closes with a discussion on grinding performance."

Jan 1, 2016

By C E. Gordon Brown

Aircraft utilization, weather and cost data are given for three separate projects north of the sixtieth parallel in the Northwest Territories and the Yukon Territory. These operations, carried out by helicopter-equipped geological and prospecting parties, have cost $24 to $30 per square mile, depending principally on the distance from the base. They provide adequate surface exploration of areas with 40 to 50 per cent rock outcrop. A good one-inch-to-one-mile geological map can be made. T HE exploration of the Canadian northland has been given increasing attention by the mining industry during recent years. In many cases, the initial problem is to make an adequate reconnaissance of a large area where existing geological information is meagre. The Geological Survey of Canada pioneered the use of helicopter-equipped geological parties for mapping at a scale of eight miles to the inch.

Jan 1, 1964

By D. E. Deegan, G. Holcroft, T. P. Johnson

"The rising cost of extracting metals from existing traditional deposits, increasingly stringent environmental regulations and a greater awareness of corporate social responsibility issues are all factors in stimulating the examination of mine tailings and small-scale alluvial deposits as a potential source of new raw materials. Furthermore, despite tougher economic times the demand for commodities remains strong, in no small part as a result of the growth of the world’s emerging economies.This combination of social and economic factors looks set to continue in the long term which will encourage greater recovery of materials from previously ignored sources such as mine tailings and ores from alluvial deposits.An expansion in the recovery of useful materials from mining-related activities is likely to require the use of robust and innovative techniques that have a built-in degree of future-proofing; DC plasma technology is one such technology.As a result of its ability to separate the valuable metal and minerals from the waste material while destroying hazardous compounds, Tetronics’ DC arc technology offers an alternative approach to resource recovery from a wide range of mine ores. Harmful cyanide compounds and the vast quantities of water used in conventional hydrometallurgical processing are avoided when plasma processing is adopted. DC arc technology also brings additional benefits, including: the extremely effective destruction of organic materials, the conversion of the inorganic material into a re-useable aggregate and the high tolerance of the process to fine and dusty materials. This paper presents details of Tetronics’ DC arc technology as one of the key pyro-metallurgical solutions available for the recovery of valuable materials from traditional mine ores and tailings, as well as giving specific examples of how the technology has been successfully employed in the recovery of enriched slags, ferroalloys and other metals."

Jan 1, 2016

By H. Reimer

The rates of return on investment are examined for several major Canadian mining companies. Because we are dealing with a highly cyclical industry, subjected to widely fluctuating metal prices, rates of return are examined over a 20-year period. Conveniently, the first decade examined reflects the period when the industry enjoyed incentives to develop deposits; during the second decade, incentives were reduced and the industry became the most heavily taxed industry in Canada. The high rates of inflation since 1973 have distorted the real rates of return on investment if one considers replacement cost.

Jan 1, 1977

By J. D. T. Steyl

"This paper presents a phenomenological model of the rate of iron(III) precipitation in batch and continuous autoclaves at medium temperature operating conditions. The rate expressions are based on information obtained from the literature and experimentation at low and high pulp densities. Special allowance is made for the formation of surface nuclei, which appears to be promoted at a higher iron(III) precipitate surface area, especially in suspensions of lower terminal acidity. This leads to the formation of secondary particulates and provides the required link to simulate high pulp density leaching-precipitation systems, using low pulp density batch precipitation data. In particular, the model allows direct application of the simulation to the autoclave oxidation of iron-containing copper sulfide concentrates and provides a good estimation of the relative precipitation rate of hematite, the preferred product, compared to hydronium jarosite. Some interesting mechanistic understandings of iron(III) precipitation in autoclaves are further elucidated.INTRODUCTIONThe objective of this work is to describe the rate of iron(III) precipitation and the relative amounts of hematite compared to hydronium jarosite precipitation during batch and continuous chalcopyrite oxidation under medium temperature (MT) (~130 to 160ºC) autoclave conditions. Published information has not yet revealed sufficient mechanistic insights about this sparingly soluble salt system under these conditions. The rate expressions in this paper are based in part on current literature information, supplemented by qualitative experimental observation at low pulp density conditions, in particular the high-resolution backscatter electron (BSE) images and particle size distributions (PSDs) of the precipitates. A summary of this work and insights from the literature are presented first, after which the behaviour of iron(III) in high pulp density leaching systems is used to derive a phenomenological expression of the effect of existing iron(III) precipitate surface area on the precipitation rate. The overall regression encapsulates all the experimental results, i.e., those obtained in both batch and continuous autoclave configurations (Steyl, 2012a)."

Jan 1, 2012

By R. A. Ford

The paper outlines: methods used for the determination of wear metals in motor and transmission oils; contaminents in motor, transmission and crusher lubricating oils; and viscosity determinations. Case histories and costs are presented to illustrate the value of an oil analysis program. Introduction NORANDA MINES LIMITED (BELL COPPER DIVISION) is located on the shores of Babine Lake, approximately 450 miles north of Vancouver, British Columbia. Access to the mine is by road from Topley, B.C., about 40 miles away. When a preventive maintenance analysis program was first considered, it was obvious that if samples were to be sent out for analysis, results would not be available for at least a week, due to the distance from any commercial laboratory. The assay laboratory was asked to investigate the possibility of determining wear metals on site. A limited program was started soon after production commenced, and this has now grown to include all large mobile equipment as well as crushers and grinding mills. The laboratory also now determines viscosity, fuel dilution, dirt and abrasives, glycol and water. All these results are ready within two days. This paper will outline the methods used, data interpretation, several case histories and the benefits from such a program.

Jan 1, 1977

By MacDonald W. L. F. C. A.

IN accordance with the usual approach to a participation in a panel discussion, this paper is, in some respects, intentionally controversial. I would suggest, how-ever that there is more than a grain of truth in many of the comments made. Before dealing with a particular problem. It is appropriate to set out a few of the more significant objective of an: accounting system: (1) The provision of historical data <•concerning past events, for the information of shareholders, tax authorities, etc. This data can also be used as a tool to predict the future. (2) The provision of a record to safeguard the company's assets and to form the basis of any claim for insurance or other damages. (3) The provision of an accounting framework in making an economic study of a proposed course of future action such as the development of an orebody or the outlay of a substantial sum for new equipment. ( 4) The

Jan 1, 1962

By Maureen McGuiness

"The pastefill circuit at the Bell Allard Mine in Matagami, Quebec started up in August 1999. The surface pastefill plant produces a cemented paste which is sent underground by gravity through a vertical pipeline in the mine ventilation shaft. Difficulties with paste flow during the start-up highlighted the importance of understanding paste rheology and the effect of operating procedures on line wear. By June 2000, the original circuit had been modified to include a paste pump to transport the paste to the shaft.The steps taken during the paste plant commissioning are discussed. The final flow sheet is presented, focussing on the use of instrumentation to ensure full column flow and proper distribution underground. Resistance modelling and accelerated curing of samples are examined as possible ways of predicting paste resistance to ensure compliance with the mine’s paste specifications.INTRODUCTIONCommissioning a new plant can be difficult and time consuming. The start-up of Noranda’s Bell Allard paste backfill plant was no exception. Since the first day it went into operation, the paste circuit could not meet the tonnage and paste quality requirements of the mine because the paste would not flow by gravity into the vertical pipeline in the mine’s ventilation shaft.Diagnosis of the pastefill problems proved difficult. It was only when the rheology of the Bell Allard paste was understood that the flow problems were solved. To ensure that the paste placed in the stopes meets mine requirements, two methods of paste resistance prediction are being developed."

Jan 1, 2002

By Sangjian Zhang, Zhu Xiao, Lairong Xiao, Rushi Chen, Mei Fang, Zhou Li

The copper-graphite metal matrix composites were fabricated by two different production methods: directly sintering with copper and graphite (Cu-Gr composite), and in-situ sintering with cuprous copper and graphite (Cu2O-Gr composite). During the in-situ reaction sintering, a redox reaction occurs at the interface of the Cu2O particles and Gr particles, resulting in the improved physical and mechanical properties of Cu2O-Gr composites. Compared with Cu-Gr composite, Cu2O-Gr composite has a higher compression strength at any given graphite content due to the improved interface bonding and uniformly distributed fine graphite particles in the matrix. Increasing graphite content decreases the mechanical properties of the copper-graphite composites. The compression strength of Cu2O-Gr composite is 50-100 MPa higher than that of Cu-Gr composite. INTRODUCTION Copper-graphite composites have been widely used in industry due to their low density, relatively high strength and hardness, good thermal and electrical conductivity, arc ablation resistance and self- lubrication ability (Grandin & Wiklund, 2018; Han & Xu, 1999; Huang et al., 2017). Electric sliding contact friction pair in the high-speed railway system and motor brush in electric contact components have a very high demand on electrical conductivity and self-lubrication ability of materials. The electric devices need to bear both mechanical load and high electric current. Copper-graphite composites with good mechanical, electric and self-lubrication properties are the best candidates for application in multifunctional electric sliding contact frication components. The relative sliding speed of friction pair is developing towards 100 m/s or even faster, which can withstand the electric flow of more than 800 A, and it is often accompanied with vibration and impact (Guo & Ding, 2008). Conventional wear-resistant materials can no longer meet the current requirements and this promotes the development of copper- graphite composites with excellent comprehensive properties (Ding, Chen, Zhu, Zhang, & Zhou, 2009; Yasar, Canakci, & Arslan, 2007). There are many ways to fabricate copper-graphite composites, mainly including powder metallurgy method, liquid immersion infiltration method, rapid sintering method and electrodeposition method (Kalin & Poljanec, 2018; Kim, Lee, & Han, 2014; Liu et al., 2018; Wang et al., 2018). Each method has its own advantages and disadvantages, and the powder metallurgy method is the most commonly used one due to its simple process, high economic benefit, and industrial production applicability. The common steps of the powder metallurgy method are as follows (Samal, Parihar, & Chaira, 2013): firstly mixing the copper (copper alloy) powders and graphite with a certain ratio, following by die-forming, and then sintering at the high temperature with or without pressure. The advantage of copper-graphite composites is that the graphite distributed in the copper matrix uniformly and it can form a carbon diaphragm preventing the wear of the composite (Fu & He, 2010). However, the bonding strength of the interface between the copper matrix and the graphite is relative low as the combination between them is mechanical interlocking but not metallurgical bonding (Ma et al., 2008). It is meaningful to develop new fabrication technology of copper-graphite composites with better interface bonding, which could provide guidance for the design of copper-graphite composites with excellent comprehensive properties.

Jan 1, 2019

By D. G. Eskin

"It is well known that it takes some time for the solid phase to completely dissolve upon melting, especially inside the defects of insoluble particles, e.g. oxides. Until then the oxides remain active solidification substrates in the case of subsequent solidification. It is also known that ultrasonic melt treatment causes grain refinement through activation and dispersion of solidification substrates (one of the mechanisms) and also accelerates the dissolution of solid metal in the melt. In this study we combine these effects and demonstrate that the introduction of an alloy rod into the matrix melt of the same composition results in significant grain refinement, this effect being increased by the ultrasonic vibration of the rod. The achieved grain size is comparable to that obtained by a standard Al–Ti–B grain refiner. All samples were cast using a standard TP-1 mould to enable correct comparison. The effect of the temperature range of the rod introduction, as well as the effect of ultrasonic vibrations are discussed.INTRODUCTION The fact that by introducing solid metal into the melt one can achieve structure refinement is rather well known. As early as in the 1930s–1950s a series of papers and patents have been published, showing the benefits for grain refinement when dissolving solid metal in the melt before solidification (Danilov and Neimark, 1938; Scheil, 1956). Later on this way of structure refinement was developed further and dubbed “suspension casting” or introduction of “internal chills” (Madyanov, 1969; Zatulovsky, 1981). The solid metal was added in a form of cut wire, cut sheet, or powder, with the resulting grain refining, elimination of columnar grain structure in ingots and castings of steel, copper and aluminium alloys. The underlying mechanisms have been suggested as (1) rapid cooling of the melt due to the latent heat consumption upon melting of the solid metal with the resultant melt undercooling and (2) introduction of many solidification substrates in the form of crystal fragments and active non-metallic inclusions (Danilov & Neimark, 1938; Balandin, 1973). A number of patents have been filed where either the same solid alloy or a master alloy with additions (e.g. Ti for Al alloy) is introduced in the amounts up to 50% (typically less than 10%) into the melt close to the liquidus temperature (Schmidt, 1966; Talbot & Soller, 1973, Krupp, 1974; Bondarev, 1979). The main reason that this technique is not widely used in industry is the possible incomplete dissolution of the solid parts introduced into the melt with ensuing inhomogeneous as-cast structure and potential defects. Also the selection of the temperature range where the technology works the best is not clear."

Jan 1, 2018

By L. Tejeda, J. R. Donald, R. Parra, J. Duran, P. H. Lauzon

"Crucible slag tests were employed to evaluate different refractory brick classes for the Cerro Matoso electric furnace. Comprehensive analysis was conducted to evaluate the crucible erosion and characterize any slag/refractory reaction products.The classes of refractories investigated were:•,tar-impregnated magnesia;•,rebonded fused grain magnesia-chrome;•,direct bonded magnesia-chrome;•,alumina-chrome;•,picrochromite; and•,magnesia-alumina (spinel).It was concluded that tar-impregnated MgO bricks were the most suitable for the slag chemistry and furnace environment according to corrosion and infiltration resistance. A picrochromite (MgCr2O4) brick performed exceptionally well with regards to erosion resistance, however, the slag infiltrated extensively through the brick pores. Alumina-chrome, direct bonded magnesia-chromite, and spinel (magnesia-alumina) bricks were evaluated as not suitable for use in the furnace."

Jan 1, 1999

By P. S. Arthur

The copper I SAS MELT? process is a submerged lance bath smelting technology. In the 20 years since the process was first demonstrated on a semicommercial scale at Mount Isa in north-west Queensland, Australia, copper ISASMELT? plants have been constructed to treat concentrates or secondary raw materials around the world. The process is operating in smelters in Australia, the USA, Belgium, India, Germany, China and Zambia. ISASMELT? plants have been installed to improve the environmental performance of operating smelters and reduce costs for smelting companies. A new copper furnace is being commissioned at Southern Peru Copper Corporation in early 2007, while more furnaces are under design for installation in Kazakhstan and Peru. Copper ISASMEL T? plants are supplied as complete technology packages including engineering design services for the furnace and key ancillaries, supply of core equipment, provision of intensive training programs in operating plant environments and commissioning assistance services. The proven technology transfer process ensures successful implementation of submerged lance bath smelting into large scale plants. This paper summarises developments at recently constructed copper ISASMELT? plants.

Jan 1, 2007