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By B. J. Morash

"The six mineable coal seams at Quintette Coal Limited (QCL) vary in thickness from 0.75 m to 9.5 m and include waste partings varying from 0.2 m to 4 m thick. They are highly faulted and folded in some areas and dip angles range from horizontal to 90 degrees. Due to this variation in thickness and orientation of the seams, several different mining methods are used to economically recover the coal. The key to QCL's success depends on the timely collection of detailed geology data and on mine planning which allows selection of the best method of mining to achieve maximum coal recovery with minimum dilution and cost. This paper will describe the various methods of mining employed and the criteria used to select them. IntroductionThe unique challenge in mining at Quintette Coal Limited (QCL) is to extract large quantities of coal and waste, from a complex orebody, with constricted areas for mining and waste disposal. This challenge dictates the mining of as many as four 10 m benches per year, through complicated coal structures, from three separate open pits with a total of 19coal seams. This total is made up of 5 seams at Mesa, 8 seams at Wolverine and 6 seams at Shikano (Fig. 1).Computer-aided mine planning and scheduling is carried out on a routine basis to ensure the prudent selection of methods of mining, to produce plans which ensure delivery of appropriately blended raw coals to the plant, and to coordinate disposal of large quantities of waste.Several methods of mining are applied simultaneously, and as a result coal and waste are released at different rates from twelve to fifteen mining faces. In order to ensure uninterrupted flow of material from excavators and to utilize the truck fleet effectively, a computerized dispatch system is employed.GeologyGenerally, geological conditions can be related to structural (faults and dip angle) and/or stratigraphic (coal seam and interseam waste thickness) sources"

Jan 1, 1988

By I. M. Gordon

"INTRODUCTIONThe Hollinger tailing disposal plant is situated about 1 1/4 miles south of the mill. The area available for tailing covers 620 acres and is roughly 1 ¼ miles long by ¾ mile wide.Tailing was first deposited on the northeast section of the present site. This section, 1 mile long by ~ mile wide, sloped from northeast to southwest, the slope amounting to 106 feet between the northeast corner and the low land to the south west. The low land was wet and a considerable area was covered with muskeg up to 17 feet deep. It was drained by a creek running across the property in a southwesterly direction. Later, when more ground was needed, the low lying mining claims adjacent to the south and west boundaries were acquired to allow for expansion of the plant. This entailed some extra difficulties and expense that would not have been necessary had the whole of the present site been acquired with the original purchase.At the conclusion of milling, May 7, 1968, the site contains nearly 56 million tons of tailing. The top of the deposit is from 70 to 90 feet above the original low lying ground along the northwest, west and south boundaries."

Jan 1, 1969

By S. A. J. Hopper

"The Golden Manitou mine is in the northeast quarter of Bourlamaque township, Abitibi county, Quebec. During the summer of 1937 a body of gold-silver-zinc ore was outlined in a series of diamond drill holes located to the west of an old copper-zinc showing in the property of Quebec Manitou Mines, Limited. In 1938, a shaft was sunk and the orebody further explored from levels at depths of 210 and 360 feet.In 1941 the western half of the Quebec Manitou property was acquired by a new company, Golden Manitou Mines, Limited, and the installation of a mining and milling plant was at once undertaken. Milling started in August 1942. The following is a summary of production to December 31, 1946:The orebodies are sulphide replacements in a sericite schist shear zone. They vary in width from 8 feet to 65 feet and range in length up to 850 feet . Much of the ore is of the 'massive sulphides' type . The sulphide minerals in the ore are pyrite and sphalerite with minor quantities of .galena, tennantite, chalcopyrite, and arsenopyrite. Native silver (as wire and leaf silver) has been found in vugs and as coatings along fractures. In one section of the mine a few specks of gold were observed. Spectrographic analysis of ore samples has indicated the presence of zinc silicate."

Jan 1, 1954

By E. Stansfield

Coal samples are sometimes taken from a wet spot in a mine, or from an open car or pile shortly after rain, and submitted for analysis in a dripping wet condition. Other samples are taken from a dry spot in the mine, or from an open car or pile after a period of dry weather. Comparison of the analyses obtained in the two cases would be absurd, although the samples might be of essentially the same coat apart from the surface moisture on the one. The analyst therefore attempts to reduce all samples to an equal basis by the operation known as air-drying. Air-drying is practised by the chemist for three reasons: (1) To make it possible to grind the coal to powder. (2) To bring the coal sample to a condition in which it will not change in weight rapidly whilst portions are being weighed out for analysis -in other words, to bring it into equilibrium with the air in the laboratory. (3) To determine the water-retaining power of the coal. Any kind of drying is satisfactory for (1); the coal should be dried more or less according to the humidity at the time in the laboratory for (2); whilst it should be always dried to the same extent for (3). In other words, no method can be satisfactory for both (2) and (3). In this paper the only question considered is (3) -that is, air-drying the coal under standard conditions so that strictly comparable results can be obtained for the water content of coals after air-drying. After a sample of wet coal is exposed, it loses moisture until it is in equilibrium with the air at the time: thus the coal will loose distinctly more water in air of 20 per cent relative humidity, for example, than it would in air of 80 per cent.

Jan 1, 1923

By W. E. Johnston

At last year's Annual Meeting a paper by Haultain and Johnston was presented entitled Is the Gold in Tellttrides Soluble in Cyanide? Since then the writer has continued the study of various phases of this problem. Samples and specimens of ore from some of the Kirkland Lake mines have been studied and non gold-bearing tellurides have been found in these that are not soluble in ordinary mill solutions. Samples of tailings, both old and recent, from this district have been examined with apparatus and methods that have proved very successful in detecting the presence of extremely minute quantities of tellurides. Tellurides, both base-metal and gold-bearing, have been discovered in these tailings, but only in such minute quantities that their presence would not affect the ordinary assay results. More free gold particles have been found in the tailings than gold-bearing tellurides. Much experimental work has been done on tellurides, concentrated from high-grade material and from ordinary run-of-mine ore. The gold-bearing tellurides behave very much as does gold itself. Finely divided particles are dissolved fairly rapidly, coarser particles more slowly. All the tellurides are soft and brittle and also have a high specific gravity, with the result that they are extremely finely divided in ordinary mill practice. The ordinary high-lime solution of Kirkland Lake practice is suitable for the dissolving of the gold tellurides. Oxygen is necessary, but apparently not more so than in dissolving gold. Some particles have been found that appear under the microscope to be ordinary metallic gold particles, but on heating they show a small telluride content. These appear to dissolve more slowly than gold. There is considerable variation in the ratio of tellurides to gold from different points in the mines. So far the writer has failed to find any connection between this ratio and the richness of the ore. Generally speaking, the base-metal tellurides predominate. Some of these contain gold but this may be due to a mixture of tellurides in the one particle.

Jan 1, 1933

By C. C. Allen, H. H. North

"The Young-Davidson mine is in the southeastern part of Powell township, in the district of Matachewan. It is 32 miles southwest of Kirkland Lake, 48 miles southeast of Timmins, and 25 miles by road Northwest of Elk Lake. The Young-Davidson and its neighbour, the Matachewan Consolidated mine, are the two present producing properties in the district. The Matachewan area is the southwestern extension of the Kirkland Lake belt or 'break'. The Young-Davidson mine since coming into production in 1934 has been operated by Hollinger Consolidated Gold Mines, Limited. ""Desultory prospecting(1) has been carried on in the Matachewan area from time to time since the discovery in 1906 of silver in James township at Elk Lake, and some gold has been found in the southeastern part of Alma township and in the central part of Cairo township. The first real interest in the area, however, was started by Jake Davidson's discovery in 1916 of gold on Davidson creek, on what is now part of the Young-Davidson property, and by Sam Otisse's discovery shortly afterwards on claims a short distance to the east, now part of the Matachewan Consolidated property. In subsequent years both of these properties were investigated by various companies; the Young-Davidson chiefly by the Porcupine Gold fields Development and Finance Company, Limited, and the Matachewan Canadian by the Colorado-Ontario Development Company, Limited, which in 1919 was reorganized under the name of Matachewan Gold Mines, Limited. Work was discontinued as the ore was considered too low in grade to be mined"". However, in 1933 Hollinger Consolidated Gold Mines, Limited, undertook to bring the property into production and this became a reality in 1934.The total production to the end of year 1945 was 319,185.59 oz. gold and 73,541.94 oz. silver from 3,228,845 tons of ore. This represents an average grade of $3.67, including exchange and premiums."

Jan 1, 1954

By S. Itoh, T. Nagasaka, J. Ono

With respect to the recycling of used lead-batteries, a pure lead is required to prepare a lead-calcium alloy electrode for a new maintenance-free battery. The pure lead can be obtained by means of electrolytic and/or pyrometallurgical refining. In the lead electrorefming, antimony is concentrated in anode slime. From the viewpoint of the recycling and recovery of metal values from used lead-batteries, especially from anode slime, oxidation experiments were conducted for pure liquid antimony in the temperature range between 973 and 1373 K to elucidate the oxidation kinetics and mechanism. Furthermore, since lead anode slime generally consists of antimony, lead and bismuth, experiments have been also carried out using antimony-lead-bismuth alloy. The equation relating to the mass transfer characteristics in the gas phase was then applied to analyze the oxidation kinetics. As a result, it was found that the anode slime treatment, that is, an oxidation of antimony concentrated in anode slime followed by vaporization as antimony oxide Sb406, should be operated with higher oxygen partial pressure and sufficient amount of gas flow rate at lower temperature around 1073 K. The feasibility of the oxidation treatment for anode slime has been also discussed.

Jan 1, 2004

By Henry Brehaut

"It is difficult to know how much environmental information is absorbed by those in a position to put it to use. The following information may seem like ""old stuff"" to those whose companies are taking steps to improve their environmental performance. This paper is directed in particular to those people who are interested in determining what further changes are required to make improvements as concerned environment citizens.IntroductionUntil recently, the author was comfortable with the fact that none of the operations for which he was responsible had any environmental charges against them. It was not until one of his operations was charged with non-compliance that the author discovered due diligence as a way to avoid a second charge, and when an unfortunate spill occurred at another operation, the meaning of risk prevention was learned. Knowledge was gained step by step to the point where finally environmental information is being heeded, rather than waiting to learn from sad experience. With the appreciation of what it takes to do a good environmental job, comes an understanding of the challenge that lies ahead, and the fact that there is a lot to learn.At a recent environmental gathering, comments from the participants varied considerably. Some just didn't understand why government was being so unreasonable, while at the other end of the spectrum one individual whose company was well along the path to becoming a good environmental citizen remarked that it was all very basic. What was immediately understandable to one went right over the heads of others, indicating the different stages that have been attained in the acceptance of environmental responsibilities."

Jan 1, 1991

By J. A. Bossert

"In 1957, the Department of Mines and Technical Surveys (now Energy, Mines and Resources Canada) issued their first certificate for a fire-resistant conveyor belt. The testing procedure used was a combination of those used in the U.S.A. and the U.K. Subsequently, certification was granted to fire resistant electric cables (1974), fire-resistant mine duct material (1976) and fire-resistant hydraulic fluids (1978).Until recently, the testing procedures were copied from either the U.S. or the U.K. However, since the founding of the new Canadian Standards Association (CSA) Steering Committee for Electrical/Mechanical Mine Safety in 1981, these requirements have come under the close scrutiny of new CSA technical committees who will attempt to adopt or change the existing procedures to meet Canadian needs. This paper outlines the existing test requirements and attempts to predict how they will appear after ""Canadianization"" by the CSA committees.IntroductionFires in underground mines have always been considered more serious than in other locations because of the confined space and limited atmosphere. A fire can make escape difficult or impossible if it is blocking all of the routes to the surface. Also, the products of combustion from an underground fire can asphyxiate anyone not having self-contained breathing apparatus.In an underground coal mine, the consequences of a fire can be even more serious because of the presence of methane and coal dust in the atmosphere (which can explode) and because the coal itself is combustible.For these reasons, the inspection authorities having jurisdiction over underground mine s in Canada are quite concerned about the flammability of any materials that are used in quantity in the underground environmentAs early as 1957, the Canadian Explosive Atmospheres Laboratory (CEAL) was asked to certify conveyor belting as fire-resistant. This is because many miles of this material are used in underground mines in Canada and, as it generally travels through the mine, it is a perfect vehicle for spreading a fire."

Jan 1, 1982

By M. Remillard, M. Garon, M. Thérien, D. Hodouin

"Nineteen streams in the copper and zinc flotation units of the concentrator of the Matagami division of Noranda Inc. have been sampled for particle size distributions chemical assays, and gold and silver contents in each particle size interval. The data are upgraded by the mass balance package BILMAT. These results, in conjunction with microprobe analyses, are used to quantify the silver losses in the copper clean¬ing flotation stages and to determine how overall silver and three silver-bearing minerals are recovered in the plant final products.RESUME Dix-neuf produits des circuits de flottation du cuivre et du zinc de la division Matagami de Noranda Inc. ont été échantillonnés pour leur distribution granulométrique, analyses chimiques et le contenu d'argent et d'or des fractions granulométriques. Le bilan métallurgique a été obtenu à l'aide du programme BILMAT. Ces résultats couples avec une etude minéralogique à la microsonde sont utilises pour quantifier les pertes argentifères aux diverses étapes de nettoyage du circuit de cuivre et pour de¬terminer la repartition de l'argent et des trois minéraux argentifères dans les produitsfinals de l'usine.INTRODUCTION The Matagami division of NORANDA INC. produces copper and zinc concentrates from a sulphide ore which contains a small amount of gold (0.34 g/t) and silver (20 g/t). Only a small part of the silver (~-30%) is presently recovered in the copper concentrate. The objective of this study is to evaluate the metallurgical behaviour of silver, and secondarily of gold, in the flotation circuit for a possible increase of its recovery in the copper concentrate to improve its economic value. For that purpose it is worthwhile to study the minerals which bear silver and to determine the critical flotation stages where they are lost in the tails. The methodology proposed here is based on a coupling of a mineralogical study and a detailed mass balance calculation in the flotation circuit."

Jan 1, 1986

By Qing-Xun Low

Ni current collector has excellent electronic conductivity and mechanica, properties. However, nicke, cannot be used in H2S-containing syngas SOFCs due to sulfur poisoning and coking. Copper coated nicke, is prepared by electrochemica, deposition. XRD, SEM, and EDX techniques are used to characterize the samples. After high temperature treatment in syngas containing, the coated samples exhibit high resistance of coke formation and sulfur corrosion compared to pure nickel. Therefore, copper coated nicke, is a promising anode current collector for H2S-containing syngas SOFCs.

Jan 1, 2010

By P. Woo, N. Brodusch, R. Gauvin, H. Demers

The scanning electron microscope (SEM) was primary developed for imaging applications. With the introduction of the Si(Li) energy dispersive spectrometer (EDS), simultaneous imaging and x-ray microanalysis became possible. However, long working distance and high current were needed because the position and small solid angle of the EDS detector. The high spatial resolution is generally obtained at short working distance with a SEM. Unfortunately x-ray microanalysis is never performed in the best imaging conditions. The annular silicon drift detector system is inserted below the objective lens which gives a higher solid angle (up to 1.3 sr). In consequence, a lower working distance and probe current can be used. An improved spatial resolution becomes possible during x-ray microanalysis. With this x-ray detector installed on a cold-field emission scanning electron microscope, quantitative x-ray microanalysis with high spatial resolution at low beam energy and low current becomes possible with the possibility of using the various different type of imaging at the same time. Also, since the count rate can be as high as 1,500 kcps, which lowers significantly the detection limit of elements as well as the minimum feature sizes of different phases that can be distinguished.

Jan 1, 2014

By M. E. Austin

Many numerical models for the tubular solid oxide fuel cell (SOFC) exist, with various degrees of sophistication. However, the question of what physics must be modelled, and what can be neglected has not been resolved. A parametric model is proposed and analyzed to quantify the influence of thermal phenomena such as reaction heat generation, cathode channel convective cooling, and thermal radiation with participating media. Currently, a three-dimensional model is used to simulate the conditions of an anode supported cell in the centre of a tube bundle. The interconnect and nickel foam spacers that bridge adjacent cells in series and parallel, respectively, are neglected thus enabling a domain consisting of a 45o azimuthal section of the tube. The conservation equations for mass, energy, and species transport are solved using commercial computational fluid dynamics software, and radiation heat transfer is also modelled using a Discrete Ordinates method. Finally, temperature-dependent material properties and reaction rates are used. The model predicts lower overall temperatures than models that do not include radiative heat exchange and more moderate temperature gradients than those that ignore participating media radiation. Further, different regimes are identified, from convection dominated heat transfer to radiation dominated heat transfer. The results can be used to aid in the selection of appropriate models for a given fuel cell operating regime.

Jan 1, 2005

By Roger Reed

It is well known that the performance and carbon emissions associated with the modern gas turbine engine depend critically upon the properties of the nickel-based superalloys, particularly those used in single crystal form. However, the design of all alloys in current use has been essentially empirical, or at best heavily reliant upon regression/neural network analysis of experimental datasets. In this paper, alloy design approaches [1] are described which are able to identify new alloy composition spaces which are worthy of experimental study. It is shown that a large amount of design data can be generated, which can be interpreted in different ways. Of course, the success of the approach depends heavily upon the accuracy of the underlying sub-models. Estimates of the creep resistance, cost, castability, density and oxidation resistance are made. It is demonstrated that these methods allow quantitative trade-offs to be made between the properties of interest.

Jan 1, 2010

By T. Cutard, H. Marzagui, E. Ouedraogo, M. Roosefid, M. Prompt, C. Deteuf

The present work is achieved in the framework of a French national program on modeling and experimental characterization of the thermo-mechanical properties of refractory materials (PROMETHEREF). This research program is aimed to establish fair models and experimental database and to make it available to industrial partners for numerical simulation of industrial structures made of these materials. The present paper focuses on two silica-alumina refractory castables, an andalusite based one and a bauxite based one. We will present the first rheological characterization results achieved at room on normal and preheated samples of these two refractory castables. Refractory castables are characterized with the help of four points bending tests, compression tests and tensile tests.

Jan 1, 2004

By John E. Udd

The stability of a rock mass is influenced by the presence of discontinuities. In assessing stability, it is required that one should know the frictional and cohesive properties of these contained weaknesses. In the study performed by the authors, a number of samples of diamond drill core containing open discontinuities were tested in shear. The results obtained were compared with values which resulted from back analyses of instabilities in the field.

Jan 1, 1979

By E. M. Yates, H. M. Hamilton

"For the assent of any new mining project it is essential to determine a realistic value of revenue from the sale of concentrates.A description of the market factors influencing the concentrate terms will be presented along with a detailed review of historical terms of a smelter contract for zinc concentrates. OverviewFor the assessment of any new mining project it is essential todetermine a realistic value of revenue from the sale of concentrates.This applies at all stages of assessment through to the final feasibilitystudy. In forecasting revenue for a zinc mine the followingfactors must be considered:(a) mill recovery and zinc concentrate grade;(b) metal price forecast for all payable metals;(c) smelter terms; and(d) other selling costs.Normally, data from test work are used to determine mill recovery and concentrate grade.Market forecasting, and indeed all economic prediction is an inexact science and probably will always remain so. We have our econometric models our input/output models and a lot of other tools. But they are of no help in predicting the unpredictable. OPEC's huge increase in the price of oil was certainly the most dramatic example of this. It had a tremendous effect on the cost of producing most products world wide and on the price of these products. Any forecasts made prior to the OPEC action were obviously proven wrong."

Jan 1, 1994

By Kostas Fytas

Acid mine drainage (AMD) is a serious environmental problem that preoccupies the Canadian Mining Industry. Considerable amounts of money are spent every year in an effort to prevent or reduce the acid mine drainage phenomenon. AMD occurs when sulphide minerals (ex. pyrite) contained in rock are exposed to air and water and subsequently oxidize to produce low pH water. This acid effluent has the potential to mobilize any heavy metals contained in the rock. Coating the sulphide minerals with silicates is a new promising technology to reduce AMD. Pyrite is treated with a solution containing H2O2, sodium silicate and a buffering agent. H2O2 oxidizes a small part of pyrite producing ferric iron (Fe3+) ions. These ions subsequently react with the silicate ions to produce ferric hydroxide-silica that precipitates on the pyrite surface producing a passive coating. This silicate coating can protect the grains of pyrite from oxidation. This paper presents a series of experiments that confirm that silicate coating can considerably reduce AMD.

May 1, 2001

By DAVID C. MILLER

Barite deposits occur worldwide and in a variety of geological environments. In recent years, several deposits of barite and barite-lead-zinc have been discovered in northern British Columbia, Yukon Territory and Alaska. Most are associated with Devonian-Mississippian age sediments, and many are syngenetic, bedded-type deposits. The Mel is a barite-lead-zinc deposit; it lies within Lower Cambrian strata and appears to be of epigenetic replacement origin. Figure I is an aerial view of the property from the south. Observations herein described are based largely upon field work, megascopic studies and two recent B.A.Sc. theses (Biasucci 1979, Rennie 1979).

Jan 1, 1984

By Rachel S. Prudhomme, Michael L. Jeremic

"The consolidation of mine backfill by free zing is a concept which has been under study in the mining engineering laboratories at Laurentian University during the past three years. The proposed underground application of freezing involves the artificial freezing of in-situ backfill by means of a refrigerated brine solution which would be circulated through a circuit off freeze pipes. The most interesting findings to date are: (I) The uniaxial compressive strength off frozen fill is considerably higher than that of cemented fill in a ratio of 20:1 (aggregate to cement), and (2) load deformation characteristics of the frozen fill suggest that a higher ice content results in more brittle failure and that samples which have initially failed can still support up 10 one-half the ultimate load without additional failure.Although at this early stage a derailed economic analysis of the procedure has not been possible, a general evaluation of the costs involved suggests that the method could be competitive with the hydraulic placement of cemented backfill. Results obtained from laboratory investigations indicate that the freezing of backfill is a structurally feasible option .IntroductionGround consolidation by freezing is based on the principle of transformation o f water contained in an aggregate-slurry into ice, which act s as a binding agent between the bulk particles, and which results in the transformation of a granular soil into a ""rock -type"" material. The abrasive nature of the particles enhance s the strength o f the ice by providing internal friction. As a result of this internal friction, the chances of plastic flow of the frozen mass when in a loaded condition are reduced(1). T he strength of a frozen aggregate is al so dependent on the grain shape of the aggregate particles which may or may not promote particle interlocking(2) and on the temperature since, below the freezing point of the water/aggregate mixture, the strength of the frozen mass increase s with decreasing temperatures.In the shaft sinking industry, artificial freezing of loose , unconsolidated soils has been in practice for several decades. Shafts for Saskatchewan 's potash industry have been sun k to depths of 3000 feet by employing artificial freezing to stabilize the Blairmore Formation(3). The common procedure for freezing ground for shaft sinking is summarized as follows(4,5): I) 150 mm diameter bore holes spaced on 1.5 m centres are drilled in a circular pattern with a radius of 1.5 m outside the periphery of the proposed shaft."

Jan 1, 1985