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Up to thirty years ago, coal preparation in western Canada, except at four plants, had not included actual coal washing. The exceptions were at Nanaimo and Royston, B.C., where tub washers and wet tables were in use; at Hosmer, B.C., using. Robinson cones; and at Leitch Collieries, Passburg, Alta., using a feldspar jig. The two last named collieries had a short life and were not operating in 1920. The industry was divided, as at the present day, into two sections, steam (bituminous) coal and domestic (largely sub-bituminous) coal, the first generally supplying industrial needs and the second householcl and other heating requirements. The two sections overlap to some small degree today as prepared sizes, chiefly stoker, and briquettes, from steam coal are shipped for house-hold use, and domestic slacks are used in certain industrial plants. The .domestic operator, for reasons shown later, was not primarily concerned with actual coal washing as a phase of coal preparation, and bent his efforts to improvement of screening and loading plants, with hand-picking of coarse sizes. The bituminous operator, on the other hand, felt it necessary by 1920 to consider coal washing. When the mines were comparatively young, coal quality could be controlled to a considerable degree by selective mining, by leaving behind some of the seam or by-passing districts in a mine where the coal was of inferior quality to that in other districts. This obviously had its limitations, and so the next step was coal washing.

Jan 1, 1952

By R. I. Kraydenko, A. N. Dyachenko

"The possibility of SiO2 5N production by staged purification of ammonium hexafluosilicate (NH4)2SiF6 is discussed. High-purity silicon dioxide can be obtained with fluoridation of quartz concentrate by solid NH4F at 100 °C, with further sublimation of the product at 320 °C, its dissolution, ammonia hydrolysis, filtration and drying of SiO2•nH2O. This is accompanied by regeneration of the processing reagent - NH4F.INTRODUCTIONProduction of high-purity silica-5N (SiO2 content over 99.999%) is an important and urgent task of the modern chemical industry. This material is used in the manufacture of optical glass, optical fibers for internet cables, silicon for solar power and electronics.Quartz concentrate is raw material for the production of silicon dioxide. The existing technologies of synthetic silicon dioxide were introduced in the mid-twentieth century. These methods are energy-consuming, multi-step and do not meet stringent environmental requirements. In fact, as some conventional technologies became obsolete; it became necessary to develop new methods for the production of synthetic silica. We believe that the fluoride technology of processing of quartz materials by ammonium fluoride is the most promising direction.In industry, silicon dioxide marked ""Silica White"" is obtained by liquid-phase method. The method consists of the precipitation of amorphous silica from sodium silicate solutions with acids. The resulting product is filtered, washed and dried. Depending on the deposition conditions and nature of the coagulant the ""Silica White"" is acidic, neutral or alkaline. The dry product is subjected to grinding. The degree of dispersion and porosity of the particles of Silica White depends on the nature of decomposition agent (a substance that decomposes the silicate) and coagulant, conditions of sedimentation, filtration and drying. During the drying process the silica particles are sintered into aggregates of a few millimeters."

Jan 1, 2012

By S. C. Robinson

"IntroductionALTHOUGH most uranium deposits of the Canadian Shield lie along its western and southern margins, those of the Lake Athabasca region extend easterly along the north shore of the lake and beyond to Charlebois lake. The western end of this belt of deposits, in the vicinity of Goldfields, is 80 miles from the Palaeozoic contact, and its eastern end, at Charlebois lake, is 240 miles from the nearest Palaeozoic rocks.Deposits in this belt may be grouped in four districts, which are, from west to east:(1) The Goldfields district, an area approximately 20 miles square, centred on Beaverlodge lake and extending eastward from St. Joseph's point to Moose channel.(2) A small area in the vicinity of Sucker bay, which is about l0 miles east of Fond du Lac.(3) An area including Middle lake to the northwest shore of Black lake at the Nisto mine.(4) A fairly large area extending northward from the eastern end of Black lake, through Charlebois lake to Spreckley lake.HistoryThe region has stimulated interest in mining circles since the reconnaissance survey of J. B. Tyrrell of the Geological Survey of Canada in l893, who reported concentrations of iron along the north shore of lake Athabasca. The deposits were staked and re-staked up to the early 'twenties' but are too lean to form ore."

Jan 1, 1952

By C. A. Grandison

The economic evolution from an agrarian society to an industrial and service-oriented economy is apparent to most students of history. The long-term trend is almost taken for granted, it does not require explanation — it is accepted as the nature of man to improve his standard of living. However, there are fluctuations around this trend line which have provoked a great deal of thought. The ability to understand and control these fluctuations would yield many benefits, it would eliminate economic waste and public hardship, and would no doubt make a few fortunes. I f it is not possible to control or eliminate these fluctuations, then a reasonable forecast of the tinting, rate of change and magnitude of the fluctuations would be invaluable to industry and government.

Jan 1, 1976

By A. Ghahreman, M. Oliazadeh

"Heap leaching is an attractive process for low grade deposits where the metal content of ore does not justify the high cost of milling and agitated leaching. In general, the heap leaching capital cost is low, construction is rapid, and production costs are low. The primary disadvantage of heap leaching is low recoveries (typically 65% of agitated leach recovery); thus, recovery improvements could convert more lower-grade deposits into minable reserves. This will also allow to process primary sulfide ores and result in a dramatic expansion of the technology, as ~80% of total ore types are sulfidic in nature. The old gold operations tailings are another massive source of low-grade gold material that can be retreated by the heap leach process. The major parameters affecting the recovery rates are ore characteristics (mineralogy, particles size of metal and host minerals, ore permeability), and operational conditions (segregation of ore, compaction, leach cycle time, lift height, and solution application rates). The design of a percolation leach process is based on a limited number of coarse ore bottle roll and/or column tests under ideal conditions. The economics of the projects and engineering design of the process facilities are developed based on the bench scale test work results and the application of the conventional engineering scale up factors. This paper will deal with the parameters affecting the HL efficiencies and focus on the potential improvement of gold heap leach recoveries. This would include design of heap leach operation and evaluation of processes such as fine crushing and bioleaching.INTRODUCTION Gold heap leaching is a hydrometallurgical process designed to treat amenable low-grade gold ores that contain typically 0.5 to 1.5 g/t gold (Marsden and House, 2006; Wong Wai Leong and Mujumdar, 2010). Ore is stacked by various types of equipment on an impermeable barrier, and a sodium cyanide solution is applied to the surface of the stacked ore. Gold, silver, and other metals contained in the ore are dissolved to various degrees by the cyanide application, as it percolates downward through the stack of the ore. The pregnant leach solution (PLS) is then collected at the bottom of the heap. The PLS is then sent to the gold recovery plant where the metals are extracted. The barren leach solution (BLS) is then reapplied to the top of the pad. Ore is placed on a pad or previously leached lift by various means, including ramp conveyor belts, radial-arm and self-leveling stackers, and trucks. Once trucks are used to construct the pads, the pad can be compacted and hence the pad should be graded and ripped or scarified (roughened up) with wheeled or tracked equipment to produce shallow cuts to increase surface area exposure to the leachate."

Jan 1, 2019

By A. Lam

The use of a liquid fed direct methanol fuel cell (DMFC) as a power source for micro and small portable applications is attractive due to its system simplicity, low temperature, etc. The aqueous methanol is directly oxidized and does not require additional fuel processing steps as in reformate based PEM fuel cells. In addition, the use of a liquid fuel is advantageous with respect to humidification, stack cooling and system energy density. The DMFC however, has technological issues that must be addressed before it can be widely adopted, particularly in larger applications such as small utility and transportation. At present, the crossover of methanol from the anode to the cathode is a major limitation on DMFC performance and fuel utilization efficiency. In this paper we discuss the influence of fuel modification on the control of crossover. This involves the use of different fuel additives and concentrations to minimize crossover. This appears to be the first reported case of the use of fuel modification (additives) to reduce methanol crossover. The rate of methanol permeation under passive conditions is discussed with respect to the different conditions.

Jan 1, 2005

Applying DEM to prediction of tumbling mill performance is challenging because several different modes of breakage are active in the process. As our knowledge of breakage and computational capacity improve, it is worth revisiting previous simulation tasks which did not produce a satisfactorily realistic description of a measured process. At SAG 2006, we reported the simulated and measured outcomes of treating a well characterised ore in a 1.2 m diameter mill. This well instrumented, pilot scale mill at the University of KwaZulu-Natal has been combined with some new approaches to ore testing to allow different modes of breakage to be tested. The mill design allows the rate of generation of fine material to be measured in close to real time for autogenous and SAG mill charges. The updated simulation model estimates mass loss with particle evolution and embeds the cumulative damage and breakage. The simulated results are compared with the measured results. Issues such as relating modelling inputs to particle breakage characterisation data and the accuracy of the predictions of the models are discussed.

Jan 1, 2012

By J. R. Gill

Introduction The property and plant of the Falconbridge Nickel Mines, Limited, is situated about 13 miles northeast from Sudbury, in Falconbridge township, near the eastern extremity of the southern Nickel Range. As early as 1899 or 1900 some work was clone on this property by the late Thos. A. Edison, when a shaft was sunk through 80 feet of overburden to within a few feet of the ore-body. At this point quicksand was encountered, which made it impossible to continue with the equipment at hand. As a result, the activities of the Edison party ceased in this section. There was no further progress until 1915 and 1916, when an extensive diamond-drilling campaign, carried out by the E. J. Longyear Company, located the ore-body that is now being worked. The property was acquired by the present operators in 1928, and in September of that year active mining development was commenced. Features Influencing Design Of Plant Early in 1929 plans were prepared for a smelter and the necessary crushing and sorting plant. In spite of the general trend towards the reverberatory furnace as a smelting unit, it was decided to erect a blast-furnace plant. The limited tonnage to be treated, of course, influenced this decision to a great extent. However, it was known that, with the proper procedure, extremely favourable results, both economic and metallurgical, could be obtained in blast furnace smelting. The possibility of very low slag losses, the simplicity of operation by the elimination of roasting plant, fuel plant, etc., the ability to handle coarse feed, and the lower initial cost, were considered factors in favour of the blast furnace. Notwithstanding the fact that we might be called on to treat a certain amount of concentrate, it appeared that the blast furnace was the proper unit for the contemplated operation.

Jan 1, 1932

By K. Sun

The exothermic behavior of the intermetallic reactions inside an Al-Mn metallic powder compact and its assimilation fundamentals in molten aluminum were examined. In this study cylindrical compacts were manufactured and tested. The experimental work involved simultaneous temperature measurements of three thermocouples as well as detection of the apparent weight of the cylindrical specimen during its assimilation in liquid aluminum. The details of the intermetallic reactions prior to the compact complete disintegration were investigated by microscopically studying the morphology and local composition in a partially reacted compact. The variation of manganese concentration in the melt was determined by chemically analyzing the samples taken from the molten aluminum at specific time intervals. The exothermic reaction increases the compact's temperature above that of the liquid aluminum. In tandem with this exothermic reaction, the compact is suffering a swelling action. This swelling action disintegrates the cylindrical specimen, which is assimilated into the liquid aluminum. The intermetallic reactions proceed in a stepwise manner. Both the bath temperature and the compact composition impact on the exothermicity of the intermetallic reactions. However, when the amount of Mn in the compact is greater than 75-wt%, the maximum centerline temperature rise is slightly reduced as Mn amount increases.

Jan 1, 2004

By G. I. Mathieu

"An experimental study was carried out to evaluate the performance of column flotation versus conventional flotation for the recovery of molybdenite from a Newfoundland ore. The objective was to verify the claims made by the inventors of the flotation column, Messrs. Pierre Boutin and Remi Tremblay, that their apparatus reduces the entrainment of fine gangue and other mineral impurities in the froth product. The research included a factorially designed series of tests to determine satisfactory operating conditions of the column. These provided a basis for comparative flotation tests with column and Denver cells. In the course of the work, the action of a few depressants was studied. Results indicated greater selectivity in the column and reduced reagent consumption."

Jan 1, 1972

By J. Beddoes

Many high strength aerospace alloys undergo solution heat treatment (SHT) and aging to develop precipitate strengthening. Most simply, SHT involves an isothermal hold in a single phase region followed by relatively rapid cooling to develop a super-saturated solid solution from which precipitates form during aging. However, subsequent properties are sensitively dependent on the details of the SHT, which frequently also serves a homogenization function. Altering the details of the thermal cycle during SHT significantly improves the properties attained during aging, as presented by examples of SHT design for titanium aluminide intermetallics, polycrystalline and single crystal superalloys, and 7075 aluminum.

Jan 1, 2010

By D. Song

In this paper, the differential equations governing the mass transport and the electrochemical reaction in a cathode catalyst layer of polymer electrolyte membrane fuel cells are solved based on the polynomial series expansion method. Explicit expressions for the polarization curve as well as for the distributions of oxygen, current density and overpotential are obtained when a quadratic, cubic or quartic polynomial is employed to approximate the oxygen concentration distribution. These kinds of explicit solutions are desirable for MEA design and diagnosis purposes. The comparison between the conventional numerical approach and the explicit solution approach proposed here shows that satisfactory accuracy can be reached by the first four terms of the polynomial series. The effect of the catalyst layer thickness on the accuracy of the obtained explicit polynomial solutions is also discussed.

Jan 1, 2005

By A. S. Eve

The detection of magnetic dykes by using magnetic variometers is the oldest application of. geophysics to mining, and is also one of the more simple and certain methods 0f locating such deposits. As a result of recent improvements in the instruments, it is now possible to find the dyke, deter-mine with magnetic variometers its strike and dip', with fair accuracy, and to estimate the approximate depth of overburden when there is no outcrop. The application of electrical methods may be used to distinguish mineral from diabase dykes. The authors have had an opportunity of making surveys with the modern Askania types of vertical and horizontal variometers over magnetic dykes in the Sudbury region. The interpretation of the results has been confirmed by diamond drilling in some cases, and by experiments over models. The variometers used were the standard form of Askania instruments (1). The sensitivity of the horizontal type was 17.2 gammas per division, and that of the vertical variometer double this quantity. To make a preliminary survey of the district, parallel lines were laid off two hundred feet apart running north and south, and readings were taken with the vertical variometer every 100 feet along these lines. This can be done very rapidly, and when an indication of a magnetic deposit is found, the readings may be taken every hundred feet, or less if the size of the deposit warrants smaller intervals. If the deposit is a vein or dyke, the readings along the adjacent lines immediately indicate the strike of the body. Thus the presence and strike of a magnetic dyke, whether of mineral value like the pyrrhotite and nickel deposits of the Sudbury district, or simply a worth-less diabase dyke, is simply and rapidly found.

Jan 1, 1932

By M. E. Sirkka

"INTRODUCTIONInco Ltd. has ten operating mines in the Sudbury district. Over the last ten years mining methods have changed at Inco with special emphasis on the introduction of bulk mining replacing conventional mechanized cut-and-f ill and undercut-and-fill methods. At the same time, the technology and size of LH D equipment has also progressed to meet the demands of bulk mining. This paper will concentrate on various aspects of the introduction and operation of electric LHD equipment a t Inco Limited, Ontario Division. BackgroundInco Limited received its first electric 2 cu. yd capacity LHD in July 1975 at Creighton Mine. The unit was tested pulling shrinkage stope muck and then was moved to a mechanized cut and- fill complex on 6600 Level. The electric scooptram received quick acceptance from the operators, due to its quiet operation and low heat generation, in a relatively hot operating environment. Although there are only two of these units operating a t present, this initial favourable experience, both in cost and efficiency, led to the development and purchase of electric scooptrams of the 5 cu. yd size. There are currently eleven 5 cu . yd electric LHDs in operation.The most recent development a t Inco is the move to yet larger electric LHDs in the 8 cu. yd size. The first electric ""Eight"" has now been in operation at Copper Cliff South Mine for over a year. This unit has the distinction of being the first one of its kind in service in North America. At the time of writing, there were ten 8 cu. yd electric ma chines operating in Inco's Ontario Division Mines, with three on order."

Jan 1, 1989

By K. D. Peaslee

Slag splashing is an important development that has dramatically improved BOF vessel campaign life and reduced operating costs. This paper highlights research from physical modeling work using a 1/8-scale room temperature model BOF and slag characterization studies from several plants in North America and China. In the model studies, gas flow rate during blow and viscosity of the liquid were found to be two of the most important factors to changing the overall rate of liquid splashed onto the vessel sidewalls. When the flow rate was increased or viscosity decreased, the lower regions of the walls were splashed at a much greater rate. It was also shown that by changing the lance height, more liquid was deposited in the upper regions of the vessel at the expense of lower regions. Reducing the number of nozzles was found to be the most effective method of selectively coating a particular vertical section of the wall. Studies of BOF's using slag splashing in North America and China showed a difference in the melting characteristics of the final slag. Generally, slag splashing is successful when the melting point of the slag is 220-270°C below the tap temperature to maintain a balance between fluidity and refractoriness.

Jan 1, 2004

By J. G. Martin, J. C. Campbell

THE VICTORIA JUNCTION 31,4-million-ton coal preparation complex went into operation in October 1976."' It is designed to produce a metallurgical coking coal by lowering the sulphur and ash content of the raw coal using a heavy-media cycloning process to treat deslimed crushed coal, with scavenging of fine coal by flotation from the primary minus-28-mesh screen product. A secondary H-M cyclone scavenges a thermal-grade coal from the primary H-M cyclone tailing.

Jan 1, 1985

By G. Bartolacci

In a COREM-McGill collaborative research and development project, gas dispersion parameters and froth properties were manipulated in a copper flotation plant to study interactions between the collection and the cleaning zones. In this paper, specific work on developing some relationships between operating conditions and froth stability in several different types of flotation cells is reported. Froth stability, measured by image analysis, was related to the following process conditions for specific flotation machines in an industrial case study: Gas flow rate, collector dosage, pH, frother type and dosage. Across the range examined, froth stability was improved through an increase in gas flow rate and/or frother dosage. Metallurgical results (grade and recovery) showed that both gold and copper were dependent on froth stability. Results indicated that flotation conditions could be optimized by monitoring froth stability.

Jan 1, 2007

By E. Thomson

This type of microscopic investigation, although still in its infancy, has already found practical applications in several different phases of mining activity. The study of the transparent minerals in rocks, by means of the ordinary petrographic microscope, has for long been a very useful supplement to observations in the field, but the opaque minerals, until recently, have had to rest content with a more or less superficial determination with the hand-lens or the blow-pipe. In a great many cases, particularly where the association of metallics has been somewhat complex, this has been entirely inadequate, and the determination of these opaque minerals under the micro- scope, has opened up a new field of scientific investigation that bids fair to surpass, in practical value at least, the micro-scopic determination of the rock-forming minerals. As the details of this kind of microscopy are possibly not entirely familiar to all mining men, it might be well to outline them very briefly before dealing with the practical directions in which this method may be applied. The ordinary petro-graphic microscope, with but one extra attachment, will serve for this work. A small reflecting device, called a vertical illuminator, is inserted immediately above the objective lens. This reflects the light down to the surface of the specimen and from here the light is directed up the middle of the microscope tube to the eye. As it is desirable that the maximum amount of reflection should be secured from the surface of the section, it is first polished and set in a position perpendicular to the vertical axis of the microscope.

Jan 1, 1924

By Hector Monette

"AFTER SPENDING a lifetime in the mining industry it is normal that one should be concerned with the future of his profession, especially if he is directly responsible for the education and formation of future mining engineers. It is not necessary to insist on the importance of mining for Canada and for the entire world to prove the necessity of the Mining Engineer. A statement was made by Zay Jeffries, former vicepresident of General Electric Co., and here I quote: ""Even though minerals without man are of no moment, man would not be man as we know him without minerals ... ""minerals are as essential to the life of social man as food is to man himself"". This certainly expresses magnificently the purpose of the mining profession. These are the reasons why I have accepted to present my views on the future of the Mining Engineer. If I express some concern it is not because I feel that there is any danger for the profession to disappear; men will always respond to a challenge and this can be found in the extraction of minerals as well as in any other field of human endeavour. However, the first big question concerns the competitive position of Canada in the world of mining. To be made available to Canadians and to the rest of the world, all this tremendous potential mineral wealth that our country has been so generously endowed with by nature must be gained from the earth's crust at a competitive cost. Otherwise it will never become ore and will have no value. Let us not forget that although minerals are discovered, mines are not found but are made. So let us be more efficient mine makers. To accomplish this end, it is the duty of the different responsible organizations at all levels - be they governmental, para-governmental, public or private institutions - to do their utmost to assure the profitable development of our mineral wealth. The University has an all-important role to play in preparing all the specialists required by this intricate machine that mining is. All the different disciplines of engineering, health, social and -managerial sciences are needed for the good functioning of the mining industry. Although they are all essential, some will play a more important role as a member of the structure. In this discussion it is the role of the most important member, the mining engineer, who is actually responsible for the extraction of the minerals from the earth's crust that must be established. From this we will then be able to analyse his responsibilities and try to suggest the mining engineering program most suitable to prepare this engineer for his future role."

Jan 1, 1972

By R. R. Montigny

A brief description is given of the history, location and geology of the Granisle Copper Limited operation on Copper I land in Babine Lake. Detailed information is given with regard to pit design, planning, drilling, blasting, excavation and haulage. Equipment maintenance and mining costs are also presented.

Jan 1, 1971