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By D. M. Muir

Many plants produce iron(II)/(III) waste liquors which must be treated by neutralisation and precipitation to remove the iron. Iron can be precipitated as crystalline goethite or jarosite by controlled oxidation at low pH and as magnetite by controlled oxidation at high pH, but only at elevated temperatures (>70°C). This study focuses on the characterisation and settling properties of the iron oxides produced at ambient temperatures using various neutralising agents in order to improve the performance of thickeners. It was found that two-stage addition of caustic to FeC12 solutions produced a fast settling material characterised by Mossbauer spectroscopy and XRD as maghemite and magnetite. However, lime and magnesia additions resulted in more ferrihydrite formation and much lower settling rates because of the enhanced oxidation of Fe(II) by air. Settling rates decreased significantly as the proportion of Fe(III) to Fe(II) in the liquor increased. The mechanism of iron oxide precipitation is discussed together with some reasons for the different behaviour of the neutralising agents.

Jan 1, 2006

By Oliver B. Hopkins

"WE HAVE patterned our lives on the things we take from under the earth's surface. Our civilization is built upon the ore from which we obtain our metals and the fuels which power the world as we know it.Today I should like to discuss with you a newcomer to the ancient mining industry. This lusty infant of which I speak is just a century old - the oil industry.While one doesn't commonly think of oil men as delvers in the earth, It was by sinking a shaft that the first oil was obtained commercially in Canada. Men sank a shaft in a ‘gum bed' in southwestern Ontario's Lambton county, not far from Petroilia, and distilled from the gum a burning oil That was just a hundred years ago. The gum was originally liquid petroleum which had seeped to the surface and lost most of its volatile components.Later, the miners dug down to •bed-rock and soon after they were not digging but were drilling wells, as they have been ever since. From the wells they obtained erode oil.What is crude oil? It is not an element like gold, silver or lead, •but a complex mixture of compounds. These compounds are made basically from two elements, carbon and hydrogen, and are called hydrocarbons (Figure 1).The remarkable ability of these. Two elements to combine in different ways gives crude oil its physical and chemical character. The lighter hydrocarbon compounds in it are gases, at normal temperature and pressure, and these are dissolved in the other, heavier compounds."

Jan 1, 1952

By J. J. Denny

IN a preliminary paper (1) it was shown that the addition of small quantities of metallic aluminium powder almost completely inhibited the solubility of siliceous material in the beaker. Six rabbits exposed to quartz dust for six months all showed well developed silicosis. Seven rabbits exposed to quartz dust plus 1 per cent metallic aluminium powder for the same period did not develop silicosis. At that time, we were not in a position to state either the manner in which metallic aluminium reduced the solubility of siliceous material, or, from the animal experiments, whether the aluminium was acting locally or systemically, or for what period after the cessation of dusting it would continue to act. This paper reports the further progress of this investigation. CHEMICAL EXPERIMENTATION The technical details pertaining to the various substances used in the experiments are given in an appendix which is on deposit with the American Documentation Institute, Washington, D.C. For lack of space, it is not printed here. The term 'solubility' is used to indicate the concentration of silica in the solution under the conditions as noted, determined colorimetrically (2), and expressed as parts per million (p.p.m.). The term 'reduction in solubility' indicates the difference between the solubility of the .silica in the presence of the aluminium powder and its solubility in the absence of aluminium powder. It will be noted that the solubility figures for different samples of quartz with no added aluminium vary considerably. The figures do not refer to an equilibrium solubility of silica but to the actual amount of silica dissolved from a given sample in a given time at a given temperature. In view of the fact that quartz dissolves extremely slowly, it is evident that the actual figures in any case will depend upon the surface exposed, i.e., fineness of grinding of the different samples.

Jan 1, 1939

By W. A. Lang

COAL of sub-bituminous rank underlies much of the plains area of Alberta. This coal is geo-logically young, and occurs in Belly River and Edmonton strata of Up-per Cretaceous age. Generally, the seams are flat-lying, but in some areas they may dip as much as 5 degrees. The overburden, composed mainly of glacial clays and sand-stones, may vary in depth from a few feet to several thousand feet. Recovery of the coal has 'been by drift, slope, and shaft underground mines, and by open-pit stripping operations. Production has been obtained from a large number of mines, most of which have been relatively small and with preparation equipment limited to a loading tipple with screening facilities, and a picking belt where high-ash materials can be removed from the larger sizes. The coal has been sold for domestic and industrial space-heating, for production of process steam, and for power generation. In re-cent years competition from natural gas, propane, and oil has seriously interfered with the production and marketing of sub-bituminous coal, especially with the disposal of the smaller sizes at a realistic price.

Jan 1, 1958

By A. Karzhau, B. Aldamzharov, Y. Tussupbekov

"This case study produced for the metal mine operating in Kazakhstan, which has ventilation controlled manually and working continuously at maximum speed to keep air flowing through each part of the mine 24 hours a day. The mine auxiliary ventilation has been designed with the maximum length of ducting systems with extra air volumes to compensate for potential leakage. The mine provided auxiliary ventilation to all production stopes even to those, which for various operating reasons become temporarily inactive. However, mine safety has to consider risks associated with the deficit of fresh air for mine gases dilution and removal. The mine needs additional investments for re-designing ventilation network and therefore needs to estimate financial risks associated with it. The aim of this study is to conduct risk analysis for ventilation network optimisation processes at the operational metal mine in Kazakhstan. Mine ventilation surveys were undertaken for validation of the computerised ventilation model. The mine ventilation network modelling has been undertaken to be compliant with Kazakhstan mining regulations. Results of the mine ventilation optimisation processes were analysed in terms of financial risks for investments into reconstruction of the ventilation shafts, extension of the ventilation network, variable speed fans and automated regulators. Savings were resulted from improving ventilation system efficiency by reduce airflow in areas without mining activity and redistributing existing ventilation capacity. Based on savings derived from the optimised ventilation network an additional NPV has been received. Stochastic modelling use Monte Carlo simulation producing representation of possible outcomes for the additional NPV considering electricity pricing as a major variability. As result probability distribution for the optimised ventilation network demonstrates the additional NPV in a range of 1.6 - 2.2 million US$ in the corresponding defined value of 90%. Moreover, there is only 5% chance that the additional NPV to be less than 1.5 million US$. Conducted risk analysis for ventilation network optimisation processes gives considerations on volume of investments into the mine ventilation system.INTRODUCTIONCosts for mine ventilation are typically increasing when mines expand to deep levels. Some underground mines in Kazakhstan still use continuously operating fans at its maximum capacity. This is not helping to save energy and costs that are in many cases very significant. This case study produced for the metal mine operating in Kazakhstan, which has ventilation controlled manually and working continuously at maximum speed to keep air flowing through each part of a mine 24 hours a day. The mine auxiliary ventilation has been designed with maximum length of ducting systems and extra air volumes to compensate for potential leakage. The mine provided auxiliary ventilation to all production stopes even to those, which for various operating reasons become temporarily inactive. However, mine safety has to consider risks associated with the deficit of fresh air for mine gases dilution and removal from the mine workings (Sabanov, 2019). The mine needs additional investments for re-designing ventilation networks and therefore need to estimate financial risks associated with it. The aim of this study is to conduct risk analysis for ventilation networks optimisation processes at the operational mine in Kazakhstan. Mine ventilation surveys for validation of the computerised ventilation model have been undertaken"

Jan 1, 2019

By Lloyd H. Yeomans

"This paper will cover recent developments in conveyor applications with specific reference to capacities, bell speeds and distances. It will also discuss certain unique arrangements of horizontal, curved and loop belt systems. In addition, the recent changes in safety factors resulting from new conveyor construction methods will be reviewed.IntroductionConveyor belt systems are currently undergoing dramatic changes. Their use is being extended to providing a viable means for the transportation of bulk material over longer and longer distances.In this paper, a brief account of the historical development' of the belt is outlined, demonstrating how conveyor technology has adapted to changing market demands.Today, energy and environmental requirements are providing what may even be greater challenges. The ability of the belt conveyor to transport material and meet those requirements, places it in the position of replacing many conventional means of bulk material transportation.The paper also outlines some of the progress which has been recently made in this regard and includes a broad approach to the subject of belt design and application.Recent design developments have greatly extended the potential of conveyor belt systems to include applications thought impossible just a few years ago.Graphically illustrating the potential of this new technology IS a belting system currently operating in New Caledonia. Built in 1970, the system has an incredible centre distance of 43,000 ft, or about eight miles.Not to be outdone, the British Coal Board is currently constructing a belt system with a centre distance of 49,000 ft and a speed of 1,650 feet-per-minute. This system is expected to be completed in 1986.These innovative advances contrast dramatically to the conveyor belt's beginnings in the early industrial revolution. Oliver Evans, writing in the 1795 edition of 'Miller's Guide' defined the conveyor belt as a ""broad endless strap of thin pliant leather or canvas, revolving on two pulleys in a case or trough.""Obviously, the conveyor belt has come a long way since those early days."

Jan 1, 1983

By A. S. Romaniuk

More than a decade ago, CANMET management recognized the need to make better use of existing technological information in mining and extractive metallurgy-two fields basic to the economic well-being of Canada. There were at that time no indexes or files dedicated to disseminating technical information for the many minerals mined and processed in Canada, including coal. CANMET, with the nation's largest research and library resources in the minerals field, was in a unique position to fill this need. Initial efforts were concentrated on building a mining file, beginning with identification of world sources of published information, development of a special thesaurus of terms for language control and adoption of a manual indexing/retrieval system. By early 1973, this file held 8,300 references, with source, abstract and keywords given for each reference. In mid-1973, operations were computerized. Software for indexing and retrieval by batch mode was written by CANMET staff to utilize the hardware facilities of EMR's Computer Science Centre. The resulting MINTEC file-one of the few files of technological information produced in Canada-is the basis for the national literature search service in mining offered by CANMET. Attention is now focussed on building a sister-file in extractive metallurgy using the system already developed. Published information sources have been identified and a thesaurus of terms is being compiled and tested. The software developed for CANMET's file-building operations has several features, including the selective dissemination of information and production from magnetic tape of photo ready copy for publication, as in a bi-monthly abstracts journal.

Jan 1, 1979

By H. Marquis

This paper is concerned with an analysis of a number of failures of large-size, hypervelocity light gas gun chambers and barrels. A brief description of the light gas gun principle and of the various types of guns is first given. The failures and the investigations carried out are then described in detail, with the failures divided into two groups. The first group comprises those failures caused by certain conditions to which the guns may be submitted, and includes, for example, severe local heating of the bore surface causing hardening and cracking of the steel. These conditions were accidental and steps were taken to prevent them. The remaining failures were due to faults in the material or in the heat-treatment, manufacturing or assembling procedures. Specific problems, such as hydrogen embrittlement, and the use of high strength gun barrels above their ductile-brittle transition temperature by preheating prior to firing, are briefly considered. Some interesting observations are also presented on the use of surface markings, and angles of fracture of large fragments, as an

Jan 1, 1962

By P. F. Venus

In December 1977, a large pillar was removed by blasthole mining methods at lnco's Creighton No. 3 mine. Although the 2,363.000-ton blast was not a size record for a single underground blast at Inco, it did represent a significant departure from conventional blasthole mining. In terms of the application of nominal 6-inch-diameter boreholes underground, coupled with bulk slurry explosives, the magnitude of the blast is considered a first and very important development. The application of large-diameter boreholes in underground operations was first tried successfully in 1973. Since that time over 13/4 million feet have been drilled in this adaptation of an open-pit technique to underground operations. The blast, which required 708 holes, totalling 131,500 feet of drilling, was loaded in a six-week period, using special slurry handling techniques developed jointly by Inco and CIL. Inco operating and engineering personnel consider this application of large boreholes and slurry explosives for blasthole mining a very important milestone in modern mining technology.

Jan 1, 1978

By R. K. Collings

The annual production of mineral and mineral-based wastes in Canada is conservatively estimated to be 400 million tons. Over 90 per cent of this amount is waste rock or mill tailings from the mining and mineral processing industry. The remainder are slags and ashes from the metallurgical industry, and sludges from the chemical industry. Because of impurity content, remote location, or both, most wastes have limited usefulness and, indeed, are a liability in that they must be transported to waste disposal sites and contained therein. Certain mineral wastes do, however, have potential value. Some contain small percentages of metals that may be economically recoverable with price increases; others consist of mineral material that may be used for such purposes as road base, construction aggregate, railroad ballast, and in the manufacture of bricks or blocks. Increased interest has been shown in mineral wastes in recent years. This paper reviews the types of mineral wastes available in Canada, briefly describes a number that have potential value, and notes possible uses and related research by CANMET and other organizations.

Jan 1, 1978

By M. Dupuis

It has been previously demonstrated [1,2] that using selective collector bar rodding has a big impact on the uniformity of the current density at the top surface of the cathode block and hence on the intensity of the horizontal current in the metal pad, The present study investigates the impact of using selective collector bar rodding on the MHD stability of a 500 kA aluminium electrolysis cell, For this purpose the recently developed MHD package for the aluminium reduction cell time dependent behavior is used.

Jan 1, 2005

By The Staff

THE gold mining industry in Canada is today the most important stabilizing influence in the country. This factor was brought out particularly during the 'depression' years, when steady employment was given to men in that industry and the monies spent in supplies and power in turn benefited the country to a great extent. At the same time, a commodity was produced which was saleable in any market of the world, thus maintaining Canada's credit in foreign markets and keeping her trade balances equalized. We have a vast area known as the Precambrian Shield. The agricultural possibilities of this area are practically negligible and it will depend entirely upon the mineral and forest resources to make this district an economic factor in the life of Canada. To date, from the mineral point of view, we have been highly successful. There are, however, still vast areas to be explored. It is tedious and laborious work, entailing great individual hard-ships and the expenditure of much energy and money. During my thirty years' experience in the search for, and operating of, gold mines, I have come to the conclusion that although individuals may give all their time, energy, and money, Governmental assistance is absolutely necessary in the development of hydro-electric power sites and roads. The Governments, to date, have given splendid co-operation along these lines, but in order that this great industry may go ahead they should continue their good work and, if possible, give greater relief from taxation to mines situated at a considerable distance from the railway.

Jan 1, 1938

By William Petruk

Image analysis studies were performed on mill products from pilot-plant and laboratory tests that had been conducted to determine the effect of grinding media on the selective flotation of two zinc-lead-copper ores. It was found that, when the ores had been ground to the same degree of fineness with flint pebbles, ceramic pebbles or ore fragments (autogenous grinding) as with steel balls, there generally was increased sphalerite, chalcopyrite and galena liberation in the flotation feeds, depending on the textures of the minerals. The increased sphalerite liberation fully accounted for the improved zinc recoveries that were obtained when steel balls were replaced by either pebbles or ore fragments. The increased chalcopyrite and galena liberation accounted for part of the changed technical efficiency of concentration, but other factors, probably changes in oxidation and reduction of iron and in consumption of oxygen, also contributed.

Jan 1, 1977

By W. F. Scott, K. L. Somerville

"This paper outlines the development and inplementation of functional training at the Thompson Mine of Inco Metals Company, Manitoba Division. This training is an extension of similar methods implemented throughout the company to meet safety and health and productivity objectives. It consists of the orientation to the mine, induction in the basic mining skills, and specific training in drilling and other skills in the mine. Initial results indicated a positive effect on the safety performance and proficiency of the mine workforce.IntroductionThe primary mining method at the Thompson Mine is mechanized cut and fill, with secondary recovery of pillars by undercut and fill . These methods require a workforce of about 900 hourly operating employees to obtain capacity production of 6500 tons of ore per day.Historically, turnover of mine employees has been high and large numbers of new recruits are introduced to the mine every year. These men are recruited primarily in Manitoba, but also from distant areas of Canada; most of the se people have no previous mining experience.Training has always been an important component of mine operations. Mine supervisors and experienced miners have committed an appreciable amount of time and effort to training these new recruits. As well, training efforts have been directed toward upgrading the skills of experienced workers.Recently, a growing awareness of the significance of this training effort and its impact on accident frequency, productivity, turnover and other important parameters of the mine operation has led to a review of training methods. The training program described in this paper has resulted from this review."

Jan 1, 1981

By R. D. Brown

"An adequate level of R & 0 is crucial to achieve gains in productivity and to strengthen Canada' s position in an increasingly competitive world ." So stated Finance Minister Jean Chretien in his April 10, 1978 budget speech, on announcing a new measure designed to increase the productivity of Canadian industry and to assist in the creation of new technology. The effect of the new measure, which permits an income tax deduction of 150% of certain research and development (R & D ) expenditures , can reduce the after-tax cost of a marginal dollar 's worth of such expenditures to as little as 20 cents . This article discusses the income tax treatment of R& D expenditures in general, and describes in particular the income tax incentives which relate to R& D.

Jan 1, 1978

By M. L. McAllister, M. Veiga

The mineral industry has seen many significant changes in the past decade. Increasingly, it has responded to unanticipated pressures and demands with a variety of voluntary initiatives. Yet there is still much to do. Mining now takes place in a different context than was the case in the past. Socio-economic, political and environmental considerations must now be integrated into traditional mining systems. This process of integration needs to involve industry, governments, academics, communities and other stakeholders to design a new approach to mining, one that can be fostered through interdisciplinary links and holistic strategies. This paper considers the meaning of sustainability in the context of the Canadian mining industry and explores the need for a broader vision for the mining industry. The role of technology is then analyzed and related to an initiative recently taken by Canadian universities to develop a national network for interdisciplinary research into sustainable mining, CaSM.

Jan 1, 1999

By S. K. Shaha, W. Kasprzak, D. L. Chen, J. Friedman, F. Czerwinski

The role of solutionizing conditions within the T6 heat treatment of the cast Al-Si-Cu-Mg alloy with micro-additions of Zr-Ti-V was assessed in terms of their influence on microstructure and mechanical properties. As a solution treatment, a single step process at 485 and 510oC and a two-step process at 510 and 525oC for varying time intervals from 0.5 to 9 h, were examined. In all cases, solution treatment was followed by isothermal aging at 150oC for 100 h. The microstructural analysis showed that the solution treatment changed the eutectic silicon morphology from needle-like, present after casting, to spherical shape in the T6 state and that the extent of changes was strongly influenced by temperature and time. The Cu- and Mg-rich phases completely dissolved during solution treatment while the Fe-containing phase, Al8Si6Mg3Fe, remained partially in the microstructure. The Ti, V and Zr containing phases, Al13Si2Ti3Zr and Al3Si26FeTiV10, present in as-cast state, were partially dissolved during solution treatment, reducing their size by 10 - 48%. The studied alloy reached the maximum ultimate tensile strength of 335 MPa and yield stress of 303 MPa for two-step solutionizing with a total time of 4.5 h. It is concluded that the two-step solution treatment resulted in higher tensile properties than the single-step process.

Jan 1, 2015

By M. Tsesarsky, M. Hazan, E. Gal

"Rock masses comprised of stiff inclusions in softer matrix are common in various geological environments. The heterogeneity and multi-scale nature of these materials make the evaluation of their mechanical properties a challenging task, which cannot be accomplished using conventional laboratory tests and composite mixture rules. We employ the homogenization method to estimate the mechanical properties of geological materials with inclusions. The homogenization method solves the equations of elasticity on the material (microscopic) scale for a unit cell subjected to unit strains under periodic boundary condition. The micro-scale elasticity equations are solved using the Finite Elements Method, and are in turn used to obtain the structure scale (macroscopic) material matrix.In this research, Finite Element models for unit cells with spherical and ellipsoidal inclusions were developed. Using the unit cells, a parametric study of the geometrical and statistical microscopic properties of the material composites was performed. The following parameters were studied: volumetric ratio, Young’s modulus ratio, size-distribution of inclusion and inclination angle of inclusions. The main purpose of the parametric study was to study the deviation from isotropy as a function of the aforementioned parameters.It was found that for volumetric ratio of 5%-40%, the deviation from isotropy increases, as the volumetric ratio of inclusions increases. For spherical inclusions, most of the cases studied exhibit quasiisotropic behaviour; whereas ellipsoidal inclusions exhibit considerable deviation from isotropy. The inclination of the ellipsoidal inclusions enlarges the deviation from isotropy (9% at random orientation and 26% at 0°)."

Jan 1, 2015

By J. Laganiere

A considerable part of the sulphuric acid requirements of the Aluminum Company of Canada's Arvida smelter comes from the burning of 180-200 tons per day of zinc '"'sulphide concentrates in a 22-ft.-diam-eter fluidized bed roaster. The plant and its operation were fully de-scribed in a publication that appeared about ten year ago (1). A simplified flowsheet of the roasting and gas-cleaning sections of the plant is given in Figure 1. The wet zinc sulphide concentrates are un-loaded into a pug mixer, by means of a Pay loader, and mixed with water in a mixing tank to make a slurry of 80 per cent solids. The slurry is transferred to a .feed tank and then introduced into the roaster at a point four feet above the constriction plate, which is the height of the settled bed of zinc calcines. The roasting temperature is con-

Jan 1, 1963

By D. M. Ziebarth

"Normal sequence of operations to develop a new underground mine is: construct and outfit headframe for shaft sinking, sink shaft, construct and outfit shaft sump, develop shaft station and shaft bottom steel. In an effort to reduce the overall project schedule, an innovative plan was developed to install service shaft steel below station level, prior to the completion of the shaft sinking effort. To better evaluate the construction of this substantial steel tower, a preliminary constructability evaluation was conducted, including the best method of supporting the main tower; from the bottom, middle or top of the tower. The design criteria and plan involved: •,Develop access from existing service shaft, 25 km underground •,Use of materials to maximize strength while minimizing corrosion exposure •,Estimating the location of the shaft centerline •,Over excavating the station and shaft below station to allow future shaft steel repositioning •,Designing the tower steel for modular installation •,Incorporate commissioning considerations, such as suspension of the cheese weights during steel installation •,Provision for covered stair access to shaft bottom •,Enclosed shaft envelope with open panels to allow visibility and ventilation The design approach was innovative and this paper will describe the design principles and challenges encountered while providing insight into the solutions developed and implemented; especially the modular construction and installation methodology. INTRODUCTION In an effort to expand the mining operations, a plan was developed to construct a new service shaft closer to the new mine workings and convert the existing service shaft to a production shaft at the Potash Corporation of Saskatchewan Inc. (PCS now Nutrien) Rocanville Potash mine in southeast Saskatchewan. The new service shaft required a multi roped friction hoist operating a cage / counterweight, rope guided conveyances to support the operational requirements. The service shaft is an integral part of the mining infrastructure as it provides access to the underground workings, transport personnel and materials underground for operation and maintenance of the mine. The shaft also allows for services required for safe operation of the underground mine, power supply, controls, communication, dewatering and fresh water supply."

Jan 1, 2019