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As a bubble travels through the pulp region of a flotation cell, it will collect the most hydrophobic particles of an intermediate particle size range, this being the primary source of true flotation selectivity. Despite its role on bubble-particle attachment, however, particle hydrophobicity is still missing a mathematical definition that can be used for plant simulation. In this paper, particle hydrophobicity is defined in terms of the induction time necessary for attachment and then linked to the mass of collector adsorbed per particle. This allows particle hydrophobicity to be written as a function of density of collector adsorption as well as particle size and mineralogy. The model is calibrated from the experimental measurement of the flotation rate constant. Liberation data from an industrial flotation rougher is used for model validation. It is demonstrated that the model can describe a broad experimental dataset by means of a minimal number of parameters. Main industrial application is in simulating the effect of the chemical environment upon plant metallurgical performance.

Jan 1, 2006

By Clifford S. Gibson

THESE troubled times suggest three reasons for maximum effort to control silicosis: (1) To keep to a minimum the ever-increasing burden occasioned by past deficiencies in this respect. (2) To effect the greatest production with maximum efficiency, which means at the least cost. (3) To preserve man-power in every way. Good control of the silicosis problem aids these aims. Inadequate control hampers all three. Insofar as our knowledge goes, silicosis in Ontario mines is caused by the inhalation of finely particulate quartz. It follows, therefore, that removal of dust containing this mineral automatically erases the cause. The achievement of this ideal is the aim of the mine operator. His best tool to this end is ventilation. This paper discusses mine ventilation from the viewpoint of dust control and it is hoped that in so doing there may result a better understanding of the part played by air in silicosis prevention. No attempt will be made to treat the subject fully. Instead, there will be presented certain salient aspects culled from field observations, the data in all cases referring to gold mines, unless mention to the contrary is made.

Jan 1, 1942

The Shortage of Mining and Metallurgical Engineers I N many parts of the Western World attention has recently been drawn to the acute shortage of mining and metallurgical engineers produced by the universities. Naturally, the reasons for this shortage have been discussed, and various remedies for it have been proposed. In this paper, I want to examine some of them. It is now fairly generally ac-cepted among mining men that the easy attractions of modern urban life have left the career of mining in the metaphorical as well as in the literal backwoods. The industry finds it increasingly difficult to recruit adventurous and intelligent young men; for such men now seek their intellectual, if not physical, adventure in more glamorous occupations from a safe social base in suburbia. The salaries, opportunities and security offered by the mining industry do not complete effectively with the rewards offered by other industries and by commerce, taking into account the social disadvantages of a mining life. The excitement and other non-material attractions of mining

Jan 1, 1965

By H. Feldheiser

Acid resistant brick linings are state of the art for anti-corrosion linings in tanks for high pressure acid leaching (HPAL) treatment. The design of these brick linings has to take into account the almost non-elastic behaviour of the brick lining inside a relatively highly elastic steel vessel. There must be tools and data available to determine for the steel vessels the thermal growth plus the pressure expansion and for the brick lining the linear thermal expansion and the chemical swell. Thermal shocks and pressure drops are not regular operating events but their negative influence on the lifetime of a brick lining has to be a part of the engineering study. Finite Element (FE) models as well as a lot of research and development on brick lining materials is the only way to find a path through the complex engineering work for pressure vessels.

Jan 1, 2004

By Michael Harley, E. Guy Charleworth

"Bedding-parallel thrust-hosted gold veins are developed in the Sabie-Pilgrim's Rest goldfield, eastern Transvaal, South Africa. The reefs display a complex history characterized by temporally and spatially overlapping events of similar mineralization and deformation. Recognition of the episodic reactivation of these low angle (5° to 10°) thrust faults implicates high fluid pressures (equalling or exceeding lithostatic pressures). Geochemical constraints limit the amount of fluid-rock interaction and the occurrence of transgressive mineralization within the Archaean granitoid basement suggests that the high pressure fluids originated at depth beneath the Transvaal Basin.Similarities exist between gold deposits of Sabie-Pilgrim's Rest and Telfer, Western Australia as well as Passagem de Mariana, Minas Gerais, Brazil. All deposits are sub-parallel to the enclosing bedding which is shallowly inclined. Furthermore, they are also hosted by contractional deformational structures and are clearly epigenetic in origin."

Jan 1, 1994

By T. A. Grammatikopoulos, B. Vasily, A. H. Clark

"The St. Lawrence deposit is a large wollastonite skarn (ca. 9 Mt @ 41.3% wollastonite) adjoining the gabbroic-to-syenitic Leo Lake pluton in the granulite facies Frontenac Terrane of the Grenvillian Central Metasedimentary Belt. It occurs within a horseshoeshaped horizon of quartzite, open to the east. The skarn extends over 1.2 km2, and comprises wollastonite-dominant, wollastonite-clinopyroxene, and diverse quartz-feldspar-sulphide (-titanite) layers, interbanded with, and strongly folded within, the quartzite. As in the world-class wollastonite deposits of the Willsboro district, New York, no carbonate protolith is preserved, and calcite is a negligible constituent of the mineralized zones. Wollastonite development is nonetheless ascribed to metasomatism of a metacarbonate unit by magmatogene, silica-rich, CO2-poor (XCO2 < 0.05) fluids, at P = 350 MPa and ca. 560°C, or, alternatively, 550 MPa and ca. 630°C.Several high-grade zones, averaging >40% but locally exceeding 80%, of translucent, white, tabular wollastonite grains, with lengths of 0.2 cm to 5 cm, have been delimited by drilling. Preliminary beneficiation studies yield high aspect-ratio and high-purity (low Fe and Mn) concentrates.St. Lawrence compares favourably to other known prospects and operating wollastonite deposits: having good chemical and physical properties, low iron content, and high aspect ratios (>20:1). In addition, the deposit has a favourable size and location, and will benefit from a low Canadian dollar. Canada currently has no wollastonite production."

Jan 1, 2003

By Michel Mellinger

This paper presents preliminary results of a project aimed at obtaining a better understanding of the genesis of gold mineralization in northern Saskatchewan using lithogeochemistry. The properties sampled were: Weedy Lake (B Zone), Waddy Lake (Komis Zone) and Wedge Lake (Twin Zone) in the La Range belt, and the Rio mine in the Flin Flon area. Although the three vein-type deposits rudied here (Weedy Lake. Waddy Lake, Rio deposit) occur in different geological situation . a common gold deposition mechanism appears to have been active at all three location . Hydrothermal fluids carrying sulphur in solution in exces of gold thio-complexes moved through fractured host-rocks until they reached a site where pyrite precipitation wa triggered. As pyrite precipitated, the a/ aAu activity ratio of the fluid decreased. until a critical thre hold was reached and gold thio-complexe were de tabilized . resulting in the co-precipitation of gold and pyrite. The conditions triggering the precipitation of pyrite appear to have been: the abundance of iron in host-rock ~ilicates at Waddy Lake. and temperature decrease upon the reaching of structural trap~ at both Weedy Lake and the Rio deposit. with additional involvement of carbonatizationrelated reactions between fluid and host-rocks for the latter. In addition to pyrite precipitation , potassic alteration of the mafic metavolcanics is observed at Waddy Lake. while at the Rio deposit, the extensive carbonatization of the host-rocks i coupled with the deposition of chlorite that may have been remobilized from the altered mafic host rocks. In both the B Zone at Weedy Lake and the Komis Zone at Waddy Lake, a di tinct vanadium signature give some clue about the direction in which the hydrothermal fluids have moved . and the interpretation made is con istent with the geological ituation in either case. As for the Wedge Lake deposits, the distinct base metals-precious metals a sociation within a sulphide-facies iron formation confirm the volcanic exhalative origin of this gold mineralization .

Jan 1, 1986

By A. A. el-Geassy, A. A. el-Tawil, Hesham M. Ahmed, Bo Bjorkman

The Iron and steel industry is one of the most intensive energy consuming processes. The majority of iron making processes is now directed towards the uses of fossil-based energy sources like coke, coal and oil. Recently, emphasis has been paid to replace part of fossil- based energy sources with renewable biomass-derived reducing agents. In the present work, the possibility of the effective use of woody biomass in carbon-iron oxide composites was investigated. Wood powder was carbonized in N2 atmosphere at 300 up to 450oC. The carbon content in the produced bio-char increased with temperature. The porosity of the char arises from maintaining the cellular structure inherent in wood biomass increases with temperature. The reduction behavior of four iron oxide-bio char composites having different fixed carbon content were carried out non-isothermally up to 1200oC in Ar atmosphere using thermogravimetric anlyser (TGA). Quadruple mass spectroscopy (QMS) was also adopted to measure the CO, CO2 concentrations in the off gases resulted during reduction process. The effect of volatile matter on the reduction of iron oxide was intensively studied. The different phases developed in the reduced product were identified by X-ray diffraction (XRD). The reduction of composites was found to proceed in a stepwise manner (Fe2O3?Fe3O4?FexO?Fe).

Jan 1, 2015

By C. M. Diaz, S. W. Marcuson

In the late 19th century, the discovery of rich nickel-copper sulfide ore bodies in Sudbury and the need for tonnage quantities of the metal to be used in nickel steel armor provided the foundation for establishing the Canadian nickel industry. For almost 50 years, International Nickel was the key player. In 1930, Falconbridge Nickel entered the field. These two companies remain the key Canadian nickel producers. This paper discusses the factors that have influenced the evolution of nickel smelting processes. The initial Sudbury ore smelting and nickel copper separation technologies were imported from abroad. It was only in 1937 that International Nickel established a process research laboratory in Copper Cliff The explosive post WW II industrial development created a strong demand for a broader variety of nickel products. For both International Nickel and Falconbridge, R&D became an essential business tool to succeed in the new market scenery. In the last few decades, new technologies were developed and commercialized to respond to the raising cost of energy, society pressing environmental concerns, the advent of nickel laterites as an important source of new metal, the incorporation of new nickel producers to the market, and, therefore, the need to increase productivity. Canada thus became an important exporter of technology. In this paper, the authors review this history with the objective of highlighting the forces that have triggered the most important changes in Canadian nickel smelting.

Jan 1, 2005

By J. D. Jones

The geographic occurrence of economic mineral deposits presents a variety of problems in modern tailings disposal operations. This paper presents case histories in several sectors of the mineral industry as well as the several stages of operations planning required for new designs, system expansion, reactivation of abandoned systems and upgrading to present environmental standards.

Jan 1, 1978

By T. Holmes, S. Davison

"A surge bin at Agrium’s Vanscoy potash operations has been plagued with flow, wear, and corrosion issues since being built in 1967. The culprits? The bin’s carbon-steel construction, geometry, and the resultant funnel-flow pattern are the root causes. An investigation and cost analysis indicated that hopper redesign and retrofit would increase production and reduce maintenance and capital costs. The retrofitted bin provides safer, more reliable operation and has a much longer predicted working life. Using this example, the authors describe bulk-solids-flow theory and highlight the importance of customizing bulk-material-handling-system design using appropriate flow properties to improve reliability, safety, and cost effectiveness.RÉSUMÉ Depuis sa construction en 1967, un réservoir intermédiaire de l’exploitation de potasse Vanscoy d’Agrium connaît des problèmes de débit, d’usure et de corrosion. Les responsables ? La construction en acier ordinaire du réservoir, sa géométrie et la structure de débit en résultant au niveau de la carotte en sont les causes fondamentales. Une étude et une analyse des coûts indiquaient que la restructuration et la rénovation de la trémie permettraient d’augmenter la production et de réduire les coûts d’entretien et en capital. Un réservoir rénové permet de renforcer la sécurité ainsi que la fiabilité de l’exploitation, et sa durée d’activité prévue en est augmentée. En se fondant sur cet exemple, les auteurs de l’article décrivent la théorie du débit de matières solides en vrac et insistent sur l’importance de personnaliser la conception du système de manutention des matériaux en vrac à l’aide de propriétés rhéologiques adaptées afin d’améliorer la fiabilité, la sûreté et la rentabilité.INTRODUCTIONIn early 2013, Agrium’s Vanscoy Potash Operations (VPO) engaged Jenike & Johanson Ltd. (J&J) to provide testing, consulting, and structural engineering services related to proposed modifications to the 270 t special standard product surge bin, which Agrium planned to undertake during a two-week shutdown in August 2013. The bin, which had been plagued with flow, wear, and corrosion issues for its entire working life, was essential for the continuous operation of two of VPO’s compaction plants and for efficient dispatching to loadout. The bin often experienced product hang-ups, clumping on the walls, and plugging at the hopper outlet. Two recent unscheduled mill shutdowns had been partially attributed to flow issues in the bin due to clumping and product plugging up at the screws. These problems increased maintenance costs, limited production capacity, and degraded product quality. Holes and paper-thin sections in the bin walls discovered during a 2013 inspection revealed the potential for major hot material leaks or even structural failure. Either issue would stop plant operations until the bin could be repaired or bypassed. Clearly, the bin cone had reached the end of its life and required replacement."

Jan 1, 2018

By J. M. Cummings

CONSIPERABLE information on the industrial or non-metallic mineral resources of British Columbia has been published. For a general resume of the subject, reference may be made to a paper presented by A. M. Richmond before the Annual General Meeting of the Institute in 1935 (1). To avoid duplication, the present paper is confined to a discussion of the existing industrial mineral industry of the Province and of the factors governing its present and future development. British Columbia&apos;s mineral production in 1936 had a value approximately 15 per cent of that for the whole of Canada. Preliminary estimates for 1937 indicate that this proportion has been maintained, although the totals have increased about 25 per cent. The following table presents comparative figures, for the year 1936, illustrating the relative importance of the major divisions of the mineral industry in British Columbia and in Canada as a whole.

Jan 1, 1938

By H. A. Wilson

Introduction Salt (sodium chloride) occurs naturally either in the solid state as rock salt or in solution as a component of natural brines. It is the major saline constituent of sea water, which contains about 4 percent salt-roughly 164 million tons, or enough to meet world salt demands for five years, per cubic mile. The great rock salt deposits of the world are generally regarded as having been formed by the evaporation of sea water over long periods of rime in wholly, partially, or periodically cut-off bays of ancient oceans. History and Occurrence of Salt in Canada We can speak today of the vastness of Canada&apos;s salt resources, but it was not always so. Settlement of our Atlantic seaboard and the Sr. Lawrence valley began in earnest in the early 1600&apos;s. The first small commercial salt works in Canada did not come into operation until 1866. Thus, for some two and a half centuries, the inhabitants of this growing country were entirely dependent on foreign sources for every pound of salt they consumed. The record shows that from at !east 1800 onward, the need for a domestic salt industry was clearly recognized by the governments of the day. It was during the Western Ontario oil-boom of 1866 that the initial discovery of rock salt in Canada was made, not far from Goderich, at a depth of 1,000 feet. A salt company was promptly organized, and with their operations there began the gradual and still uncompleted conquest of the Canadian salt market by the Canadian salt industry. Over the next thirty years many holes were drilled into the Salina formation both in Ontario and Michigan, and encountered rock salt. A vast salt-basin was disclosed, approximately outlined, and given the name Ontario-Michigan Salt Basin. The Ontario portion of the basin extends over at least 3,500 square miles, is met with at a depth varying between 800 and 1,600 feet, and has a thickness of 50 to 250 feet. No attempt has ever been made, so far as we know, to calculate the total salt reserves of this basin, but the minimum indicated in the Ontario portion by the figures just cited is just under thirty-five cubic miles. The specific gravity of rock salt is 2.2. From these data, those so inclined may calculate the tonnage.

Jan 1, 1947

By C. Schlumberger

INTRODUCTION The object of the present paper is to discuss, from a geological point of view, the practical results obtained by the authors with the method of the &apos;resistivity map of the subsoil&apos; in the study of various mining problems. Some of the studies described date from 1920, 1922, and 1923. They are, therefore, quite old, at least as far as geophysical research is concerned (1). Others, on the contrary, are very recent (2). We shall deal only very briefly with the theoretical and technical sides of the processes employed. This paper has, essentially, a practical purpose, and it has seemed unnecessary to enter into a detailed discussion of the methods. Such a discussion cannot be presented without introducing ,quite. Complex considerations both of mathematics and experimental physics, which interest only the geophysicist: whose work is highly specialized.

Jan 1, 1931

By J. A. Russell

IT IS the purpose of this paper to show how the design of the larger slope hoists in use in the mines of the Dominion Steel and Coal Corporation has tended to evolve ta suit the particular conditions of operation. These hoists are all used for hauling coal in trains or trips of pit tubs up the mine slopes, which usually follow the dip of the seam . As the mine is developed to the dip and the slope grows in length, the length of the rope and the size of the hoist required to handle it rends to become extremely cumbersome. It has been found that the best economic conditions of hoisting are obtained when the length of the slope is limited to about seven or eight thousand feet. Beyond this length it is necessary to offset to one side of the line of slope and start a second or auxiliary slope, which will be served by its own hoist installed underground. With this hoisting distance as a basis, we find that we can economically hoist the outputs required, usually about 1,500 tans per eight hours per slope, by hoisting the coal in trips of about twenty boxes. This, on the grades obtaining, will require a rope of about l 1/4in. diameter, running at a speed of 1,200 ta 1,800 feet per minute, and requiring from 1,200 to 1,800 h.p. at the hoist shaft. The tendency is for the rope speeds of the surface hoists to be a little higher than the underground hoists which relay to them, so that the surface hoist has a small margin of time in hand. The oldest surface hoists were steam-driven, but, with few exceptions, these have given place to electric hoists. With the exception of one hoist, which was altered in design, the steam hoists have not had the opportunity of evolving in the same way as the electric hoists, and will not be mentioned any further.

Jan 1, 1944

By J. W. Reynolds

Introduction The Sullivan mine, at Kimberley, B.C., is the principal source of ore for the Consolidated Mining and Smelting Company of Canada, Limited. Current production amounts to about 2,500,000 tons of lead-zinc ore a year. With approximately 1,600,000 feet of percussion drilling and 700,000 feet of diamond drilling being carried on each year, any improvements in drilling practice are important. Testing of new equipment and drill bits is a major function of the Testing Department at the mine. Tungsten carbide bits have been the subject of many tests since 1947 and have been used in operations since 1948. This paper details with the methods of testing and gives comparative data on performance and costs for tungsten carbide bits as compared to steel bits. Operational use of tungsten carbide bits started in April, 1948, and the extent of application has increased considerably since that time. The scale of employment is illustrated in Table I, which also shows other statistics on the use of carbide bits. Up to the present time eighteen types of carbide bits or tipped steel, as made by six different manufacturers, have been tested. In general, one supplier&apos;s bits have been used in operations, but some large-scale operational tests have been carried out with other types. The types tried are shown in Table II. To date they have been, the subject of 33 tests, covering the destruction of 804 bits over an observed footage of 42,586 feet.

Jan 1, 1951

By Stephan I. Zajac, Roger A. Blais, John B. Stubbins

THE iron deposits of central Labrador occur within a relatively small area, herein called the Knob Lake Iron Range, in which a northwest-trending series of low hills and ridges defines the height-of-land at the boundary between provinces of Quebec and Newfound-land. Approximately two-thirds of the deposits are in Quebec and the remainder in Labrador, with several deposits straddling the inter-provincial boundary. These deposits are being exploited in open-pit mines by the Iron Ore Company of Canada centered at Schefferville, Quebec. Since 1954 this company has produced more than 56 million tons of iron ore to become Canada's leading iron ore producer. With indicated reserves of more than 375 million tons of direct-shipping ore and large tonnages of iron formation amenable to beneficiation, this mining district is assured of a long life. This paper describes the Knob Lake iron ores and their geological settings and stresses the features that lead to a better understanding of their origin. The

Jan 1, 1961

By D. M. Rippley

THE St. Lawrence Seaway Project ranks with the greatest engineering undertakings of all time. A summary of major materials going into the construction of this project, shown in Table I, will assist in an appreciation -of this fact. These data relate to Seaway construction only, and it should be remembered that two large-scale power projects are in the construction stage on the St. Lawrence river concurrently with construction of the Seaway. A project of such magnitude as the Seaway would attract widespread interest even if it were being constructed in a remote area. The fact that it is located in a heavily populated and developed section of both Canada and the United States has done much to enhance this interest, and in many ways complicates the problems confronting the engineer in the design and construction phases. Many consider the St. Lawrence Seaway to be a new idea that has developed within the past decade - such is far from the fact, because the St. Lawrence River canal systems have existed for more than a century, and the Seaway Project is but a new, larger, and more efficient version of a continually expanding facility.

Jan 1, 1957

By Gavin A. Hunt

In order for mines to operate profitably throughout their life it is important to monitor and maximise ore recovery. A common problem facing many mines is the underestimation of clay type and its distribution in ore at the mine face, blast hole or in the ore stockpile. Too much clay entering the heap leach ore stream for example causes a dramatic reduction in heap leach efficacy and or increased leaching times. The end result is poor leaching performance and much reduced metal production. Poor clay identification and quantification is attributable to many factors, including costly and slow off-site mineral analysis techniques, such as XRD, XRF and petrology, the visual and subjective limitations of the core logging geologist and a lack of suitable low cost, high throughput mineral logging instruments. To get round these problems a new, non-contact, imaging spectrometer - the SpecCam - was developed by Spectra-Map Ltd, to allow high throughput identification and quantification of minerals from mineable material. Its novel imaging design can collect millions of data points (pixels) per day; each pixel contains spectral information that allows a wide variety of mineral types, including the smectite and illite clays, and phyllosilicates such as talc and kaolin, to be identified. Because all the ore can be imaged a much more reliable mineral log can be made. Hence, mapping changes in mineral composition - related to variations in phenocrysts, macrocrysts, veining or wall rock - is possible. Examples of SpecCam data from Goldfields Cerro Corona Porphyry stockpile and from Rio Tinto?s Argyle Diamond mine illustrate the mineral identification and quantification capabilities of the SpecCam. More importantly, for the first time very accurate % abundances for the different minerals can be obtained using an image-based modal count technique. The modular design of the camera, plus its extremely flexible high speed filter, mean that the SpecCam can be easily installed on different equipment, each one suited to different ore recovery problems. For example the SpecCam can be used on an automated portable logging frame to measure drill core, RC chips, hand samples or powder, or alternatively installed on a Geotek multi-sensor core logger for high-throughput, automated logging of drill or blast hole core using co-registered multi-sensor data. An exciting recent development has been the installation of the SpecCam on CommoDas ore sorting equipment, used around the world for 24 hour mill-feed monitoring and automatic ore sorting. Real-time ore sorting decisions can be made as material is monitored on a conveyor belt running at 3m s-1, from which the ore can be automatically sorted into high-grade, low-grade or waste streams for example. The three installation options for the SpecCam mean that most mineral analysis and automated core logging or ore monitoring needs can be met at the mine. For the first time rapid and automatic mineral identification and accurate quantification can be made. All of which allow the mine geologist or metallurgist to make important decisions about maximising the metal recovery process.

May 1, 2007

By C. E. White

The depletion of higher grade mineral reserves will accelerate the trend toward production from progressively larger and lower grade deposits. The discovery of adequate reserves of leaner ores will require the development of improved exploration techniques with a greater depth range. The principal challenges to the Canadian mining industry are to find the mineral resources required to meet fast growing world demand and to develop mining methods and equipment to ensure production costs which will strengthen our position in export markets in the face of in-creasing world competition. The challenges cannot be met without intensive efforts to attract more technical men to the industry and to improve their training.

Jan 1, 1967