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By H. F. Zurbrigg

"The Frood-Stobie Mine is by far the largest metal producer in the Sudbury area. Its efficient development was made possible by the consolidation of three mining properties that covered parts of the same ore body. They were known as the Frood Mine, the Frood Extension, and the Stobie Mine.The southwest or Frood portion of the orebody was discovered by Thomas Frood and A. J. Cockburn in 1884. Cockburn's interest was acquired by J. H. Metcalf and W. B. McAllister and patents were issued to Frood, Metcalf, and McAllister in 1884. The property was purchased by the Canadian Copper Company (lnco) in 1886.James Stobie discovered the northeast or Stobie part of the orebody in 1885. In 1886 Stobie and Rinaldo McConnell applied for the location and patent was issued in 1886. They sold the property to the Canadian Copper Company (lnco) the same year.The Frood Extension property included very little of the ore zone at surface but it covered ore down the dip from Frood. Frank Cochrane was granted title to the property in 1908 and sold it to the Mond Nickel Company in 1910. The title was transferred to the International Nickel Company in 1929 at the time of the Inco-Mond merger.Prior to 1930 the three properties produced a total of about 1 ,000,000 tons of ore from mining done during the periods 1887-1903, 1913-1915 and 1925-1929. Since 1929 the Frood-Stobie operation has produced more than 120,000,000 tons of ore, about half from open pits and half from square set and blast hole stoping. The current production rate is in excess of 6,000,000 tons per year.The principal products from the ore are nickel and copper. The by-products are iron ore, cobalt, platinum, palladium, rhodium, ruthenium, iridium, gold, silver, selenium, tellurium, and sulphuric acid."

Jan 1, 1949

By I. C. L. Webster, G. E. Ray

"The magnetite-rich Heff Cu-Au skarn lies in the Quesnel Terrane of south-central British Columbia, approximately 26 km northeast of Kamloops. The skarn formed close to the northern margin of the Heffley Creek pluton, and is hosted by Carnian (Late Triassic) Nicola Group limestone. The Late Triassic pluton (208.1 ± 6.1 Ma, U-Pb zircon) is a composite body of alkaline affinity that includes dioritic, gabbroic, and magnetite-rich clinopyroxene ± olivine ultramafic phases.The skarn has been discontinuously traced along strike for more than 1 km, and individual skarn layers are up to 40 m thick. The most common non-opaque minerals are garnet, clinopyroxene, and carbonate, with lesser epidote, biotite, amphibole, and chlorite. Apatite locally forms more than 3 vol.% of the rock. Compositionally the garnet is a low Mn grandite averaging Pyr3-Grs41-Adr56 mol.%.Mineralization consists of lenses, up to 10 m thick, containing massive low Ti-V magnetite (avg. 0.03 wt.% TiO2 and 0.01 wt.% V2O3). Magnetite is associated with up to 20 vol.% pyrrhotite, lesser pyrite, and trace chalcopyrite and gold. There is a moderate enrichment in rare earth elements with assays up to 570 ppm La and 490 ppm Ce. The Heffley Creek pluton belongs to a suite of Late Triassic-Early Jurassic alkalic and Fe-rich intrusions that are widely developed throughout the Quesnel Terrane. Some host Cu-Au porphyry mineralization, but less commonly they are associated with magnetite-apatite veins such as at the Glen Iron mine and Magnet occurrence, or with magnetite-rich Cu-Au skarns such as the Heff occurrence.Although abundant low Ti magnetite is present in the Heff skarn, it does not appear to represent iron oxide copper- gold (IOCG) type mineralization. Microprobe analyses completed during this study show that low Ti magnetite is not a unique feature of IOCG deposits, but also characterizes some other types of hydrothermal mineralization. In British Columbia these include some alkalic porphyry-related magnetite-apatite veins in the Quesnel Terrane, as well as the well-known Wrangellia-hosted Fe skarn deposits. Thus, low Ti magnetite appears to be a common signature of many magmatic hydrothermal deposits in contrast to the high Ti primary magnetite found in most igneous rocks."

Jan 1, 2007

By D. A. MacFadyen, J. J. Brummer, C. C. Pegg

"The first record of a kimberlite found in Canada (1946) was the identification of thin dykes intersected while drilling for gold in Michaud Township, Ontario.Sampling of the Munro Esker (1964) in the Kirkland Lake area, Ontario, by the Geological Survey of Canada identified the occurrence of detrital grains of pyrope garnets along a length of 35 km of the 113 km tested. A search for the source of the garnets resulted in the identification (1968) of a narrow subsurface kimberlite dyke in the Upper Canada Mine. This discovery resulted in a staking rush. Unfortunately, subsequent work did not identify the source of the kimberlite indicator minerals.During 1978 the Ontario Geological Survey started a multi-discipline study of 29 townships (2560 krn2) in the Kirkland Lake area, to encourage exploration for gold, base metals, and kimberlites. Back-hoe sampling (1979 to 1982), where the overburden was thin, and reverse circulation drilling, in areas of thicker drift, yielded samples of the till. These were analyzed for several elements and a mineralogical identification of the heavy minerals was completed. Pyrope and chrome diopside grains were identified.Studies of the Pleistocene geology indicated only the most recent direction (167 degrees) of ice advance (Matheson) and the associated deposits, out of a possible three advances known to occur in the general region straddling the Ontario-Quebec boundary, is present in the immediate area of Kirkland Lake. Contouring the distribution of pyrope grains (1990) showed a concentration centered over an area of 616 km2 extending down-ice from Gauthier Township. This included a smaller area containing chrome diopside grains. Kimberlite boulders were identified (1981) in gravel pits on the Munro and Misema River Eskers located within this anomalous area. The next step would be to use the airborne geophysical data to locate the kimberlite pipes which yielded the indicator minerals and boulders. The source area is likely to be in the northern half of the Ontario Geological Survey study area."

Jan 1, 1992

By C. H. Bertoni, A. Vachon

The Corner bay copper deposit is the first significan discovery on the south limb of the Dore Lake Complex, located at the eastern end of the Detour Lake-Chibougamau greenstone belt, Quebec. The deposit was discovered in March, 1981, after 26 years of intermittent work in the area. Mineralization is found in a shear zone cut ting rocks ranging in composition, from gabbroic anorthosites to anorthositic gabbros which have been intensely altered and deformed by at least two tectonometamorphic events. Both the copper-bearing shear zone and its host rocks are cut by a large NE-striking gabbro dyke. Most of the known mineralization is found east of the dyke, but two deep exploration holes have shown that the down dip extension is present to the west of the dyke. The mineralized shear varies from one to 15 metres in width, strikes around 010° and dips from 70° to 80° to the west, and has been tested for a length of 700 metres. The wall rocks are usually chloritized and silicified. Mineralization is characterized by chalcopyrite, pyrite, molybdenite, magnetite, and sphalerite occurring mainly as the matrix to quartz-carbonate breccias in the "main" shear zone. The predominant sulphides are pyrite and chalcopyri te as crystals or fragments. The brecciated mineralized shear shows evidence that there was at least one remobilization of the shear and it is suggested that copper-bearing fluids invaded the shear during its remobilization. The exact timing and source of mineralization are not known. Up to February 1984, 38 holes had been drilled to outline indicated reserves to a depth of 450 m of 1,5 million tonnes grading approximately 4% copper, 0.34 gm, gold and 13.71 gm silver per tonne. It is believed that there is considerable reserve potential in the block west of the gab bro dyke, the down dip extension of the main zone.

Jan 1, 1984

By J. G. Pharoah

Over the last two decades a variety of models for solid oxide fuel cells (SOFCs) have emerged ranging from one dimensional (1-D) to 3-D models, from steady-state to transient models; single- and half-cell and entire stack models. A majority of these models have focused either on the transport processes or on the chemical/electrochemical processes. The approach taken by our research group is to develop a comprehensive SOFC model framework based on the considerations of detailed electrochemical reaction mechanism and by accounting for complex transport processes occurring in the porous media at the micro-scale level. In this paper, we review the state-of-the-art in SOFC modeling and identify the existing gaps that need to be filled in.

Jan 1, 2005

By Patrick Polk

For many years, sulfuric acid producers all over the world have been forced to meet ever more strict environmental regulations to reduce SO2 emissions. The sulfuric acid industry has implemented new solutions in order to comply with the new lower SO2 emissions target. Haldor Topsoe (Topsoe) has responded to this challenge by continuously improving the range of VK sulfuric acid catalysts and providing tailor-made catalyst solutions to meet the demands of the sulfuric acid producers for lower SO2 emissions. Reducing emissions through catalysis: requires less capital than installing a scrubber, requires no additional process chemicals, generates no waste or by-product to dispose of. In 1996 Topsoe introduced VK69, a cesium-promoted vanadium catalyst, designed for operation in the pass(es) after the intermediate absorption tower in double absorption plants. The high activity of VK69 allows for a more than 50% reduction in SO2 emissions from existing double-absorption plants. Topsoe currently has more than 110 installations of VK69. To comply with the still more stringent regulations being placed on the sulfuric acid industry to lower SO2 emissions, Topsoe has developed a new sulfuric acid catalyst designated VK-701 LEAP5™. This catalyst was introduced to the market in 2010. VK-701 LEAP5™ is based on a novel technology which circumvents the internal transport deficiencies of existing commercial sulfuric acid catalysts and thereby offers exceptionally high activity in strong, SO3 rich gases. Sulfuric acid plants have used this catalyst to meet emissions requirements lower than previously believed possible with a catalyst only solution. This paper will present examples on how to reduce emissions by implementing a tailor-made catalyst solution using VK69 and VK-701 LEAP5™.

Jan 1, 2014

By B. K. Gorain, A. W. Stradling

"The traditional metallurgical scale-up techniques for flotation plants are based on lumped flotation rate constants, dimensionless hydrodynamic numbers and the use of safety factors. Once the plant has been designed, the flotation principles that govern scale-up play almost no role in the optimization of the circuit to meet its metallurgical targets. This deficiency can potentially lead to a plant design incapable of meeting its targets, especially when circuits incorporate large flotation cells. This paper demonstrates the application of the k = PSbRf model in providing a suitable framework for flotation modelling, scale-up and circuit optimization, thus presenting an integrated approach to the problem. Studies were conducted at Teck Cominco’s Red Dog concentrator to characterize cell hydrodynamics, gas dispersion properties, froth flow behaviour, entrainment and ore floatability to obtain the key data necessary to develop a model for the flotation circuit. The findings of these studies are presented in this paper, which provide valuable insights into the modelling and optimization of the Red Dog flotation circuit. IntroductionThe traditional methodology for flotation scale-up and plant design is based on the ruleof- thumb with safety factors and dimensionless hydrodynamic group similitude considerations. With the recent trend toward larger flotation cells with volumes of 150 m3 and greater in concentrators, the problem of scale-up has become even more acute. The scale-up factors that may have been tolerated on smaller cells are not applicable to larger cells. The transportation of froth in these large cells adds further complexity to the problem. Arbiter et al. (1980) foresaw this problem and pointed out that if scale-up were attempted by rule-ofthumb and trial-and-error, the probability of failure would then increase with scale. This problem is confounded by the fact that the design and scale-up considerations used for a new flotation circuit play almost no role in optimization of the circuit to meet its metallurgical target. This results in a plant design, which may be incapable of meeting its metallurgical targets. There have been several instances where new concentrators have required significant circuit modifications and additional capacity to achieve design targets."

Jan 1, 2003

By H. Abdollahi

Cold rolling is one of the most important techniques in metal forming since the cold rolling products are almost finished product, The product quality of this process is widely influenced by friction in the roll gap; therefore, controlling the friction and other parameters affecting the cold rolling is very important in order to have a product with high quality, Among the cold rolling parameters, the pressure distribution or friction hill within the roll gap is known as the most significant one, In this study, a new software (Matroll), is introduced which can determine the coefficient of friction (COF) and plot the friction hills for an industrial mill, Besides, based on rolling equations, it offers about 25 rolling parameters as outputs. To verify the software operation, the real industrial rolling data was used as inputs, The results (outputs) are in good agreements with the findings of other researchers, The COF values are very reasonable, The friction hill shows that COF is not constant over the whole arc of contact.

Jan 1, 2005

By W. P. Campbell

THE investigation herein described had its beginning in the chemical laboratory of the Department of the Interior, Calgary. After the transfer of the natural resources to the Province of Alberta in 1930, the laboratory was closed and the investigation discontinued, but in 1933, with the permission of the Director of the Mines Branch, the work was again taken up and brought to completion. OBJECT OF THE INVESTIGATION The object of the investigation as originally planned may be stated as follows : (1) To determine the chemical composition of the limestone formation underlying Turner Valley gas field. (2) To identify 'beds' in the limestone, if such existed, with definitecharacteristics which would mark them from immediately overlying and underlying measures. (3) To relate information acquired on the composition of the limestone to the occurrence of oil and gas in the particular section examined. Definite information was lacking as to the exact chemical composition of the limestone and of its variations in composition at various depths. The formation was generally referred to in the field as the 'dolomitic' limestone, but the depth to which the dolomitized zone extended and the degree to which the limestone generally had become dolomitized were not known. Jn the drilling and logging of wells, the recognition of suitable 'markers' in the various formations is a matter of some importance. Markers are generally relatively small but widespread members of a formation, which have some characteristic property, of colour, composition, or form, by which they may be identified, and with them, consequently, the formation of which they form a part. In the formations above the limestone in Turner Valley, a number of well defined and easily recognized markers are known to geologists, drillers, and others interested in the field. Many of these markers Hand out in sharp contrast to adjoining measures and are therefore easily recognized; in others, the contrast is less sharp, with consequent difficulty in identification.

Jan 1, 1937

By E. F. Evoy

"The Gunnar uranium deposit was within metasedimentary rocks of the late Archaen Tazin Group. These rocks were intensely altered by albitization so that the immediate host to the ore consisted dominantly of albite, and by the subsequent introduction of calcite. The ore consisted of disseminated pitchblende and uranophane in a pipe-shaped breccia zone. Oxidation of the ore was more intense near surface than at depth, but there was no near-surface enrichment.IntroductionThe Gunnar Mine site is on the tip of Crackingstone Peninsula, on the north shore of Lake Athabasca, Province of Saskatchewan, Canada. The peninsula forms the southern part of the Beaverlodge mining area. The ore consisted of disseminated pitchblende and uranophane in brecciated metasedimentary rocks of the Tazin Group, and the deposit was characterized by extreme albitization and subsequent carbonatization of the host environment.Production from the mine began in 1954 and the ore was depleted by 1963. In that interval the deposit yielded about 5 million tonnes of ore containing about I. 75 kg/tonne U3O8. It was mined initially from an open-pit and subsequently from underground; the open-pit contributed about 55% of total tonnage. Uranium was recovered by atmospheric leaching in sulphuric acid, ion exchange concentration, and precipitation with magnesia.This paper is based on studies made during the productive life of the mine and is concerned primarily with pre-ore alteration of the rocks containing the deposit, and with the ore mineralogy."

Jan 1, 1986

By M. C. Ethier, A. L. Laramie

"The Granisle and Bell Copper mines were officially put into production in 1966 and 1972, respectively. The Granisle Mine was purchased in late 1979by Noranda and the two operations were amalgamated as one division. Both mines were closed in 1982after sustaining heavy financial losses during a period of low copper prices beginning in 1981.This paper describes the resumption of operations at the Bell Mine in 1985 after its shutdown period of three years and the dramatic and sustained improvements in productivity and efficiency realized as a result of a commitment by employees and management to the application of Participative Management and Employee Involvement principles. After a general description of the effects of such a philosophy on the operation as a whole, and a comparison to the operation's last full year as a producer, it deals with the practice of this philosophy in the maintenance department at the Bell Mine and the superb results realized.IntroductionThe Bell Copper deposit was discovered in 1963 and came onstream as a 10000 ton s per day open pit mine in the fall of 1972. Identified reserves at that time were 46 million tons of ore containing 0.50% copper. The mine shared facilities of the townsite of Granisle with the nearby Zapata-Granby mine which had established the community six years earlier.Because of easy grinding ore and improvements to milling circuits, Bell's throughput rate was increased to 17 000 tons per day by the late 1970s. In the open pit, improvements resulted in mining of additional reserves with higher stripping ratios. At startup, a half ton o f waste was mined for every ton of ore processed.By the end of 1982, with 48.2 million tons already mined, the Bell Mine had identified additional mineable reserves of 39.4 million tons containing 0.52% Cu.In November 1979 the Granisle Mine was purchased from Zapata-Granby. The two mines, with a total of 700 employees, were operated under common management as the Babine Division until 1982 when low copper price s forced the closure of both for an indefinite period.The outlook for copper prices remained bleak and only 50 people were retained on the payroll to maintain the two plants, most of them working on a part-time schedule.The population of the Village of Granisle dwindled from over 1500 inhabitants to under 500, as people moved away to seek other employment.Prior to the shutdown, the Bell Mine employed 370 people and pit extraction averaged nearly 50000 tons per day of which 16000 tons was mill feed, and the remainder waste. Total cost to produce a pound of copper was C$1.36 in 1982."

Jan 1, 1990

By Neil McMillan

"By any measure of common practice, Claude Resources' Seabee Gold Mine in Northern Saskatchewan should not now be operating. Not because reserves dwindled, or grade dropped or prices weakened or technical problems arose, but because a host of unimaginable other problems beset the project, any one of which would normally have led to the mine's failure.The success of the Seabee Mine, and it is extremely successful, is a story of the vision and blunt determination of two men. Neither is remarkable in his own right but each possesses the characteristics which were necessary to forge a highly productive and profitable narrow-vein mine in the midst of the most bizarre and unpredictable events which likely have ever beset a mine start-up in Canadian history.Together, Bill MacNeill, a Saskatchewan born, former bush pilot and Ray Gagnon, a big hearted, hard-fisted, miner with 44 years of experience in Canada's underground, built the Seabee Mine.They didn't accomplish this with brilliant geology, outstanding engineering or nimble corporate manouvering but rather a stubbornness and raw common sense which likely are all too often, ingredients missing in failed projects.The Seabee Mine is 100% owned by Claude Resources, a Saskatoon based company taken over by Bill MacNeill, its current chairman, in 1982. The company is listed on the TSE and produces 1200 barrels of oil per day and about 60,000 oz of gold per year. The company has a strong balance sheet, is very profitable and has 18 million shares outstanding.The Seabee property in Northern Saskatchewan started out like many other gold exploration properties in Canada.It was discovered in the l 940's by what is now Cominco, and, while highly regarded by that company the property sat largely dormant until acquired by Claude Resources in 1985.Claude did what most junior exploration companies would do and went looking for a company with a depth of expertise to joint venture the property.That company was Placer Development who could earn a 55% interest in the Seabee by delivering a bankable feasibility study on the Project by July 1988 and providing financing to production.Placer Development was an excellent company and spent over $8 million dollars on the Seabee over a 3 year period. Unfortunately for Claude Resources, Placer Development merged with Dorne Mines in 1987 and the new merged company, Placer Dome, established a minimum production threshold greater than the 50,000 oz per year which the Seabee appeared capable of supporting at that time. Placer Dome's request for an indefinite extension of the joint venture agreement to allow it to drill off a larger ore body was rejected by Claude Resources and the Seabee Property was returned to Claude in 1988."

Jan 1, 1998

By S. Balideh

A good understanding of the behavior of broken rock helps to make more informed decisions regarding slope stability and waste dump issues in mines. The cohesion coefficient of rock has little influence on the strength of broken rock; therefore, a criterion based on friction and cohesion of intact materials does not provide an accurate analysis for the strength of broken rock. This paper illustrates the effective strength of broken rock through a brief literature review about failure of intact rock and rock masses. The complete stress- strain curve and some important points of residual strength of rock are summarized in this paper.

Jun 1, 2012

By G. W. H. Norman

The surficial Archæan rocks of the southern gold belt of western Quebec are constricted near Kewagama lake by granite masses to the north and south. This divides the belt into natural eastern and western parts. This paper deals with the eastern part, extending from Malanie to Haig township. In this section the Keewatin-Timiskaming rocks have a length of about 70 miles and end abruptly against garnetiferous gneisses of the Grenville terrain. In the western half of the section where exploration has been under way since the early twenties, there are sixteen mines that are or have been in operation, and eleven prospective mines. In the eastern half where exploration has been carried on since the early thirties, six prospective gold mines are under development, one· of which, Louvicourt Goldfields, is at the initial production stage. Of the sixteen properties in the western half that are operating or have operated, all, except the Golden Manitou, which is a base metal mine, and the old Green Stabell from which there was a small production of copper, produce gold. Of the eleven prospective mines in the western half nine have gold. New Bidlamaque has gold and copper and one, East Sullivan, has copper-zinc ore. Since production began in 1927 gold, silver, zinc, copper, and lead having a total value of about $10,000,000 have been produced from the mines of the eastern section of the southern gold belt of western Quebec.

Jan 1, 1954

By Jim Wickens, Andy Cole, John Pekrul

"The roaster facility at Barrick Goldstrike Mine treats double-refractory sulfidic/carbonaceous gold ore. Prior to oxidation in the roasters, the ore is ground in two parallel dry grinding circuits utilizing 19’ Ø x 75’ double rotator mills. The design plant throughput was 12,000 dstpd. However, process improvements have significantly increased throughput rates by 25-50%. The current daily throughput record is 20,078 dstpd. Grinding circuit improvements contributing to this success include feed size reduction, ball size optimization, automatic ball charging optimization, and operating strategy changes. In addition to the changes already made, this paper discusses future optimization initiatives including on-stream particle size analysis and “real-time” ore hardness determination techniques.INTRODUCTIONBarrick Goldstrike Mines is located 29 miles Northeast of Carlin, Nevada, USA. Through 2001, the property has produced over 23 million ounces of gold making it one of the premier gold operations in the world.Prior to Barrick’s ownership, the property began producing gold from a small heap leach operation in 1975. The small-scale heap leach production continued through 1986, and in January 1987, Barrick acquired the property. Increased exploration activity by Barrick significantly increased gold reserves. In August 1988, a 4,500 dstpd mill facility was commissioned to treat high grade oxide ore. Also, heap leach operations had significantly expanded. In 1990, the mill was expanded to 6,000 dstpd, and the first autoclave was commissioned to treat refractory sulfide ore. By the end of 1996, the mill and pressure oxidation facility had expanded to 16,000 dstpd and heap leaching had ceased as oxide reserves were exhausted. In 2000, a roaster facility was commissioned to treat double-refractory sulfidic/carbonaceous ore."

Jan 1, 2003

By J. O. G. Sanderson

THE Brazeau river is a relatively short foothills stream in western Alberta and its drainage area is limited to approximately 2,400 square miles. It rises near the head of the North Saskatchewan river, about two-thirds of the way from Banff to Jasper, and is confluent with the North Saskatchewan at a point about 40 miles north of Rocky Mountain House. It is not the purpose of this paper to describe the geology of all of this area. Only the central portion, which lies east of the outer limestone ranges and takes in the outer folds of the foothills belt, will be dealt with. This area is shown on Figure 1. A small portion of the area described lies in the drainage basin of Pembina river, which flows into Athabaska river. The area to be discussed may conveniently be termed the 'Brazeau area', since Brazeau is the name of the river basin referred to above, of an out-lying limestone range, and of the only large settlement or community in the region, the mining town Brazeau. One of the first Factors of the fur trading post of Rocky Mountain House in the early years of the nineteenth century was Louis Brazeau. Coal mining during the past 25 years, and more recently exploratory drilling for oil, have brought the district into some prominence. The Brazeau area was visited by D. B. Dowling for the Geological Survey of Canada in 1906 and 1907 (1). His traverses and reports dealt mainly with the Kootenay coal deposits. It is doubtful if he traversed the outer foothills area with which the present paper deals. His reports on rich coal deposits in the Bighorn Basin area attracted commercial interests, and in 1908 large tracts were leased as coal lands. James McEvoy mapped and studied the coal seams in that year, and G. S. Malloch, of the Geological Survey of Canada, made a complete survey of the whole of the Bighorn basin. His report (2), published by the Survey in 1911, describes the stratigraphical geology and names the formations. Further references to the geology of the district, mainly in relation to coal, are made by D. B. Dowling (3) and by J. S. Stewart ( 4). In the period between 1913 and 1920, the area was traversed by private interests in search of likely oil structures. A well was started in 1914 along the Saskatchewan river about 19 miles west of Rocky Mountain House, and drilling was undertaken by Imperial Oil, Limited, in 1921 at Coalspur.

Jan 1, 1939

By Jr. Arcand

Canadian Economy ? Getting Results ???? A stronger Canadian economy ???? National debt cut ???? Taxes reduced, tax-free savings account, support for manufacturing sector ???? Assisting with infrastructure Aboriginal issues affect all Canadians ???? Aboriginal prosperity is in everyone?s interest ???? Conditions for Aboriginal success include: - Indian residential school settlement - resolving outstanding specific claims

May 1, 2008

By P. Taskinen, A. Jokilaakso

The Flash Smelting Process for copper and nickel production has been one of the most successful new metallurgical process developments in the 20th century. The experimental data from laboratory scale investigations of studies has produced information and insight into the reaction mechanisms and kinetics of the flash reactions of copper concentrates. Advanced computer models coupling chemical reactions with a Computational Fluid Dynamics (CFD) software became possible with the development of commercial CFD software together with increased computing power. Currently, there are both experimental and CFD modelling, including also CFD–DEM coupling (Discrete Element Method), studies ongoing for investigating the kinetics of matte – slag reactions in the flash smelting furnace (FSF) settler. The ultimate goal of the modelling work is to develop a comprehensive FSF model for studying the behavior of changing raw materials, both primary and secondary, and distribution of their elements between the matte, slag, and gas phases. The use of User-Defined-Functions (UDF) is one way to digitalize metallurgical knowledge and experimental information to be used for supporting process experts and development of artificial intelligence applications in metallurgy. In this paper, a review of the development of the FSF reaction shaft modelling and experimental investigations, and the current work for the settler reactions’ experiments and modelling are presented. INTRODUCTION The Outotec Flash Smelting process (Bryk, Ryselin, Honkasalo, & Malmström 1958) has been used in the copper and nickel industry for 70 years with continuous support from experimental investigations by many research groups in academia, among others Jorgensen and Segnit (1977); Jokilaakso, Suominen, Taskinen and Lilius (1991), Chaubal and Sohn (1986), Kim and Themelis (1986), and in industry Mäkinen and Jåfs (1982); Kojo, Lahtinen and Miettinen (2009); Tuominen, Pienimäki and Fagerlund (2016). It has been developed also for pyrite and lead smelting (Asteljoki, Sulanto & Talonen, 1984). A schematic illustration of the FSF and other main parts of the process is depicted in Figure 1. Also, two and three dimensional physical water or gas models have extensively been used in product and process development (Lilja & Rajainmäki 1995). During the recent decades, computer based models have increasingly been adopted in the FSF research and development (Ahokainen & Jokilaakso, 1998); Ahokainen, Jokilaakso, Taskinen & Kytö, 2006; Hahn & Sohn, 1990; Jorgensen & Elliot, 1992; Zhou, Zhou, Chen & Mao, 2014; White, Haywood, Ranasinghe & Chen, 2015) to name a few, but also in supporting engineering and sales of the technology (Miettinen 2017). Even though the reactions of the sulfidic concentrate particles have been included in the reaction shaft modelling, the complete FSF model with both gas-solid/drop and molten slag/matte drop has so far been and still is too demanding for today’s computer hardware.

Jan 1, 2019

By Mohammad Mehdi Salarirad

Fouling of activated carbon by different organic species is a great concern in carbon in pulp and carbon in leach circuits. The rate of gold adsorption onto activated carbon from synthetic gold solutions which contained different amounts of potassium ethyl xanthate (PEX), potassium isobutyl xanthate (PIBX), and methyl isobutyl carbinol (MIBC) were evaluated through batch adsorption tests. The results of these experiments showed that the gold sorption rate rapidly decreases by increasing the concentration of collectors including PIBX and PEX up to 20 mg/L and at higher concentrations, the kinetic rate constant (i.e., k value) gradually leveled off to 53 h-1 for PIBX, which is 46% lower than the 99 h-1 for PEX. At low concentrations of up to 15 mg/L of MIBC, a gradual decrease of the rate constant was observed, while at higher concentrations, the decrease was found to be more pronounced. The gold loading capacity and the rate of gold adsorption onto activated carbon from a gold cyanidation pulp in the presence of flotation reagents were also evaluated. The results of these experiments showed that the flotation reagents have no significant effect on the gold loading capacity of activated carbon at prolong adsorption period, meanwhile the rate of gold adsorption continuously decreases by increasing the concentration of flotation reagents in the leaching solution.

Oct 1, 2011

By Michel Aubertin

Les activités minières peuvent produire de grandes quantités de roches stériles, qui sont typiquement entreposées dans des empilements de surface, au dessus la nappe phréatique. Ces haldes peuvent occuper une superficie de plusieurs dizaines d?hectares, et s?élever à plus de cent mètres. Pour des exploitations en roches dures, les roches stériles ont usuellement une granulométrie qui contient des particules de la taille d?un sol silteux jusqu?à des cailloux et blocs de taille métrique. La structure interne d?une halde construite sur une surface relativement plane comprend généralement deux zones principales. La première zone se trouve au coeur de l?empilement, et elle est formée par la présence de plusieurs stratifications subhorizontales (avec des couches denses et lâches) due à l?effet des équipements lourds qui compactent et brisent les grains. La deuxième zone se trouve aux endroits où les stériles ont été déversés en crête, par des camions ou des butoirs, ce qui induit une ségrégation des particules sur les flancs, le long de la pente. Selon la séquence de mise en place, la distribution granulométrique et la hauteur des bancs, un grano-classement plus ou moins développé se produit, avec les particules les plus grosses au bas de la pente et les particules plus fines au sommet ; on observe aussi une stratification inclinée due à l?avancement latéral du front de déposition. Ces éléments de la structure interne d?une halde influencent la distribution et le mouvement de l?eau (et de l?air). Pour évaluer la distribution des propriétés des matériaux dans une halde, on doit usuellement avoir recours à une combinaison de techniques qui fournissent des informations sur les caractéristiques hydrogéologiques et géochimiques des roches stériles. A cet égard, certaines techniques géophysiques sont particulièrement intéressantes car elles permettent une cartographie tridimensionnelle des variations des propriétés. Les informations obtenues de diverses techniques de mesures utilisées conjointement peuvent alors être employées afin de construire un modèle numérique qui permet d?analyser les écoulements non saturés de l?eau et le transport réactif des contaminants. De telles simulations aident à mieux comprendre la réponse de la halde dans son état actuel et futur, ce qui fournit des arguments pour ajuster la séquence de déposition pour élaborer le plan de fermeture et pour sélectionner la stratégie d?instrumentation et de suivi de l?empilement. La présentation inclura un survol des diverses techniques qui ont été développées afin de caractériser les propriétés des matériaux en laboratoire et sur le terrain, et pour obtenir un portrait global de la structure interne d?une halde. Des résultats additionnels sur la modélisation du transport réactif seront aussi montrés afin d?illustrer l?influence de la structure interne d?un empilement sur sa réponse hydro-géochimique et environnementale.

Nov 1, 2008