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By J. E. Nesset, J. A. Finch, Rosenblum. F., S. Somot

"In a previous presentation at the CMP, evidence was shown for the formation of hydrogen sulphide (H2S) in self-heating experiments on pyrrhotite-rich samples (Somot and Finch, 2006). Oxidation of H2S is strongly exothermic leading to the proposition that H2S is playing a key role in the self-heating process. Subsequently, tests in two weathering apparatus (I and II) were run under varying oxygen levels to further examine conditions leading to self-heating. To characterise their resulting self-heating capacity the samples from the weathering tests were subjected to a modified Stage B test using the self-heating apparatus developed by Rosenblum and co-workers (Rosenblum and Spira, 1995; Rosenblum et al., 2001). Results showed highest self-heating after weathering occurs under low oxygen conditions, supporting the H2S hypothesis. It was observed that highest heating rates are not directly related to highest weight gains of samples.INTRODUCTION“Sulphides” refer to several types of minerals containing sulphur in its lowest oxidation state of - 2. Self-heating is the spontaneous heating of a material without external heat input. It is well established that some sulphides will self-heat on exposure to moisture and oxygen (Farnsworth, 1977; Good, 1977; Rosenblum et al., 2001; Wu and Li, 2005). This process is highly exothermic and if the heat generated is not dissipated, combustion may occur when the temperature reaches the ignition point of the sulphide (typically 350-400 °C). The hazards of sulphide self-heating range from handling hot material, to sulphur dioxide release, to fires. The literature documents self-heating incidents underground, on ships and trucks transporting sulphide concentrates, and in mine waste (tailing) disposal areas (Stachulak, 1990; Lukaszewski, 1969; Headley et al., 1977). Lukaszewski (1969), Farnsworth (1977), and Good (1977) note that sulphide minerals can act as fuel to promote underground mine fires. Based on such findings, sulphide minerals could become classified as hazardous materials, making transport of concentrates and storage of mine waste subject to stricter and more costly regulation. The problem is one the industry is keen to avoid."

Jan 1, 2009

"The Antamina orebody is a geologically complex, polymetallic skarn located in the Peruvian Andes. A range of copper and copperzinc ores are campaigned separately through the concentrator producing copper and zinc concentrates as well as lead and molybdenum by-products.Ore type classification at Antamina is based on chemical assays; geological or lithological variations are not considered. Consequently, each ore type demonstrates a wide range of concentrator performance.Antamina is currently implementing a system to track ore movements from the shovel face to the concentrator. Relatively sophisticated models of run-of-mine and coarse ore stockpiles ahead of the mill will be used to account for the variable delay between mining and milling.One of the numerous benefits of ore tracking is the ability to directly associate the measured concentrator performance with a physical location in the orebody. Using existing mine planning software, three-dimensional models can be created of such performance measures as metal recovery, concentrate quality, operating cost, and reagent consumption.Such a database of information allows the true value of different ore sources to be determined. The value of an ore source is conventionally measured as metal content (individual or combined ‘equivalent’) with a cut-off grade applied to indicate some base level operating cost. However, the true value of an ore source should include dynamic factors like haulage cost, reagent use, smelter penalties, and even prevailing metal prices. If an ore source is considered from all perspectives rather than simply its potential to deliver value, the concept of ore becomes more flexible. Any ore source that reveals itself to be unprofitable can be eliminated from the mine plan or possibly blended with others to improve its value. The ability to predict mill performance, and thereby profitability, is a powerful tool.In an operation such as Antamina, where managing ore sources, campaigns, and the delivery of a variety of concentrates in a narrow timeline to customers is a daily challenge, prediction is the key to success and improved efficiency."

Jan 1, 2005

By G H. Reavely, The University of Western Ontario Department of Geology

The lower Middle Devonian Sylvania Sandstone occurs in the sub-surface in the western part of Mal-den township, Essex county, Ontario. The formation is composed of well rounded, frosted quartz grains with a silica content varying from 42 to 93 per cent and the grains are cemented by carbonate, constituting up to 57 per cent of the rock. This sand-stone is not a homogeneous bed but is divided by strata rich in carbon-ate cement. The thickness of the Sylvania in Malden township varies up to a known maximum thickness of 88 feet. The lower contact with the chert-bearing Bois Blanc formation is sharp but the upper contact with the Amherstburg formation (Detroit River group) exists as a transition by a gradual downward increase in quartz grains. The Sylvania would seem to outcrop in the lake bottom near the mouth of the Detroit River dipping to the north along a broad anticline the axis of which follows the Detroit River. Just south of Amherstburg, a local east-west trending

Jan 1, 1961

By A. H. Lang

"IntroductionMUCH PROSPECTING, exploration, and development work was done for uranium in Canada in 1952, chiefly in northern Saskatchewan and in the Great Bear Lake region of the northwest Territories. The outstanding feature of the year was the great amount of work done in preparing for production at the Ace mine of Eldorado Mining and Refining, Limited, in the Goldfields region . of Saskatchewan. Many private companies and prospectors were also active in this region. Most of the other parts of Canada where uranium has been found received less attention than during the last few years, partly because so much interest was taken in the Goldfields region.In presenting this short summary of the year's activities now, the writer is handicapped because the season is not yet over; some discoveries have probably not yet been announced, and there has not yet been time to digest the numerous reports that have been sent in by companies and prospectors. In any case it would be impossible to give details for most of the discoveries and properties, because that would require a long report, and because that information is classed as confidential until released by the discoverers and companies concerned. It is only possible, therefore, to give a few generalizations, a brief out-line of the activities in northern Saskatchewan, even briefer ,accounts of the work in other parts of the country, and a few details that property owners have informed the writer he may publish or that have already been published by the owners."

Jan 1, 1953

By Peter A. Hacquebard

"Two continuous coal zones occurring in a 2500f t (762 m) thick section of the Upper Carboniferous Pictou Group (Westphalian C and D) have been encountered in five offshore wells drilled f or oil and gas in the Gulf of St. Lawrence. They correlate, by means of fossil spores, with thick coals of the Mabou and Inverness coalfields situated at the eastern margin of the Basin. Therefore, the presence of a large submarine coalfield of at least 18000 sq mi. (46 620 km'] is indicated. This compares with an estimated size of 14 000 sq mi. (36260 km' ) for the Sydney Coal Basin.Accessibility is provided only by the small onshore parts of the Mabou and Inverness fields, because farther offshore the coals lie too deep to be mined (below 4 OOO f t ([ 219 m)).Two near-shore coal exploration wells indicate that at Mabou Mines the younger Inverness coals occur at a mineable depth to at least 5 km from land. A structure contour map of this area shows a reserve of 125 million tons in two Inverness equivalent seams that are 8.5 ft (2.6 m) and 4.5 ft (f.4 m) thick. The Mabou coals, however, reach too great a depth close to shore to possess mineable resources.A structure contour map of the Inverness submarine area, based on mine data and one off shore seismic profile, indicates inferred mineable resources of 160 million tons, in two seams that are 7ft (2.1 m) and 4.5 ft (f.4 m) thick . A detailed deep seismic survey will be necessary to substantiate the structure and resource estimates"",Maceral and coal quality percentage diagrams of five column samples of these seams (the 7 Foot and 13 Foot Seams of Inverness Equivalents) show a bright banded coal, high in reactive macerals, which will produce a weak coke unsuitable f or metallurgical purposes. A thermal coal with a rank of H. V. ""B"" Bituminous (0.64% Ro) is present, averaging 12000 btu llb (6 660 kcai/kg), 10% ash and 6% sulphur, of which 60 to 80% is derived from pyrite.Microlithotype profiles of the major Mabou and Inverness coals show characteristic successions that can be used f or seam identification and proved valuable f or structural interpretations.The time of faulting in the major fracture zone on the eastern margin of the Gulf of St. Lawrence Basin has been deduced from coal rank variations. It occurred in pos tPermian, probably Early Triassic time."

Jan 1, 1986

By Rob Stewart

Acknowledgements ? Josef Macek(Manitoba Geological Services) ? Sally Goodman (SRK) ? Inco Geologists ? Rogerio Montiero ? Thompson Mine Geologists Introduction ? Regional Geology ? Thompson Geology ? Stratigraphy ? Sulphide Characteristics ? Conceptual Model ? Structural History ? Belt ? Thompson Mine ? 1D Deposit ? Ore Controlling Structures ? Using Structural Data to Guide Exploration ? Summary

May 1, 2006

By A-A. Bogno, Ch. -A. Gandin, A. Maitre, H. Henein

Most metallic materials are produced from their liquid state. In order to control the properties of industrial products, it is very important to understand their solidification path and the resulting microstructures which can be significantly affected by melt undercooling. High undercooling results in rapid solidification and a refined microstructure with minimal microsegregation. This paper reports on the analysis of rapidly solidified Al-Cu droplets obtained by a single fluid atomization process, Impulse Atomization. A quantitative analysis by Rietveld refinement method of the Neutrons Diffraction data was carried out to determine the fraction of the intermetallic Al2Cu. Knowing the fraction of Al2Cu, the eutectic fractions and corresponding dendritic and eutectic undercoolings were estimated using the metastable extensions of solidus and liquidus lines of the Al-Cu system calculated by Thermo-Calc. In addition to this work, a model of microsegregation coupled with ThermoCalc software via TQ (application programming interface of ThermoCalc) and the Wang-Beckerman model for dendritic growth velocities has been developed for binary alloys. This has led to the development of a phenomenological relationship between primary phase undercooling and initial growth velocity. A comparison of estimated primary undercoolings using a coarsening model with the adiabatic undercoolings for each alloy composition has confirmed that solidification occurs under adiabatic conditions during recalescence.

Jan 1, 2014

By I. M. London, G. P. Hatch

The Canadian Rare Earth Elements Network (CREEN) was formally launched at the Rare Earth Symposium at The Metallurgy and Materials Society of CIM (MetSoc) Conference of Metallurgists in October 2013. CREEN is an industry-led, multi-stakeholder network focused on providing collaborative solutions that will advance Canada’s REE sector to produce a significant proportion of the global production of separated critical rare earth products by 2018. The Network is industry driven by companies with REE projects under development and supported by universities, engineering firms, national and commercial laboratories, and government. CREEN aims to accelerate the development and delivery of timely solutions to technical and economic issues specifically facing Canada’s emerging rare earth sector. It will facilitate partnerships with other national and international organizations to leverage existing research initiatives. It will also support training and education to ensure that the needed qualified human resources are available to achieve the sector’s goals. CREEN membership spans the full rare earth supply chain and technical support organizations, from prospective producers, advanced project developers, national and commercial laboratories, engineering consultants, university researchers, and other innovators. This paper provides an update on CREEN's developing networking and project develop

Jan 1, 2014

By J. O. Marsden

Over the past decade, the copper industry has been through an extended downturn followed by several years of sustained high copper price. A number of new technologies have been developed over the past 10 years aimed at reducing costs by decreasing energy, labor, and materials requirements, or by increasing metal recovery. The energy intensity of different copper extraction routes and different technologies varies considerably and this has a significant impact on the economics of extraction. Based on average ore grade materials, the total energy for the extraction of copper typically varies from about 24-26 MJ/lb (6.7-7.2 kWh/lb) for the mining, crushing, milling, flotation, smelting and refining route to about 14¬16 MJ/lb (3.9-4.5 kWh/lb) for the mining, crushing, heap leaching, solution extraction and electrowinning route. New technology developments are providing opportunities for significant reductions in energy consumption for copper extraction, representing energy savings up to 20-25% in some cases. In addition, in many cases, these new technologies have introduced environmental, safety and health benefits over the incumbent technology. Some of these technology developments have been more successful than others, and many hold great promise for application in the coming decade. This paper provides an overview of the technology developments that have occurred, and explores the underlying reasons behind successful implementation.

Jan 1, 2007

By Ben Bradshaw

Context ? Community engagement has become an increasingly significant and challenging part of mineral exploration and mine development; indeed, opposition from communities proximate to a proposed mine site has been known to derail technologically- and financially-sound projects. ? These cases suggest that mining firms need to better understand how to engage constructively with local communities in the pursuit of their claims. ? While a range of publications exist promoting various community engagement strategies, these recommendations, when viewed as a whole, are disjointed and largely untested in real development contexts. Aims of Presentation 1. Synthesize industry, NGO, government and academic publications focused on community engagement best practice in order to highlight those practices that are most commonly recommended. 2. Review the (Canadian) mining industry?s experience with some of these strategies based on existing case material in order to identify the extent to which commonly prescribed strategies are used and validated in practice.

May 1, 2010

By Jacob Wood, Robert Matusewicz

The Outotec® Ausmelt Top Submerged Lance (TSL) Process has achieved widespread commercial acceptance over the past 40 years for the processing of copper, nickel, lead, tin, zinc and precious metal bearing feeds. The continual development and evolution of the technology during this period has resulted in a more intense smelting process with higher energy efficiency and lower operating costs. More recently, considerable effort has been invested in decarbonisation of the process through improvements such as increased oxygen usage, dry feed injection and use of low-carbon auxiliary fuels. This paper covers a number of these recent advances to the technology and highlights their impacts on energy consumption and CO2 emissions for a range of non-ferrous smelting flowsheets. INTRODUCTION Relentless demand for improvements in the profitability, safety and environmental performance of non-ferrous smelting plants has driven a continual development and evolution of processing technologies in this industry. In response to these demands, a number of bath smelting technologies have emerged over the past 40 years and have been implemented for the treatment of primary and secondary feedstocks. The Outotec® Ausmelt Top Submerged Lance (TSL) Process (henceforth Ausmelt Process) is one such bath smelting technology which has been widely adopted in a large number of greenfield projects and brownfield plant modernisations (Wood & Hughes, 2016). Emissions of CO2 from the production of non-ferrous metals represent approximately 4-5% of global totals (Rankin, 2012), comparable with the almost 10% attributed to iron and steel production. Despite significant improvements in the energy efficiency of modern smelting technologies (Coursol, Mackey, Kapusta & Cardona Valencia, 2015), primarily through increased oxygen usage, further innovation and development is still required to address their reliance on fossil fuels such as coke and coal. Transformation of the non-ferrous smelting industry to low-carbon technologies and process flowsheets is lagging behind the power and transport sectors, which have witnessed significant growth in clean/renewable energy technologies to reduce CO2 emissions and address the issue of anthropogenic climate change (IRENA, 2018; IEA, 2018).

Jan 1, 2019

By F. W. Gray

Ideal utilization of the heat energy in coal should theoretically be secured by supplying each atom of combustible material present with the exact quantity of oxygen necessary for complete combination. An intimate and equal admixture of the fuel particles with air is therefore to be sought. Coal, or the combustible substances of which coal is composed, may be used in solid or liquid or gaseous form. The use of coal in small particles intimately mixed with air is, in effect, a specification of coal in pulverized or dust form. There has been much important development of this manner of using coal, which may be instanced as the outstanding advance in the use of coal as a solid. The completeness and efficiency of combustion in a properly designed dust-fired furnace permits the use of locally available coals of inferior quality, and enables them to be used commercially instead of imported coals of better quality. That is to say, some grades of coal of low calorific value, that are not economically useable in lump form on grates, are useable in pulverised form, because of the more complete combustion thereby obtained, and the consequent more efficient results. In the case of coals that are unsuitable for steam-raising in grate-fired furnaces, because of clinker troubles, (arising usually from a combination of high sulphur content and low-temperature fusibility of the ash content) use in pulverised form has obvious advantages, and in addition gives the benefit of any heat units that are contributed by free sulphur in the coal.

Jan 1, 1924

By Claude Bourgoin

"The Copra massive sulphide deposit occurs as a continuous slab of ore dipping at approximately 40 degrees within a sericite schist formation. The orebody has been delineated over a distance of more than 5,000 feet down dip. This paper is mainly concerned with the mining procedure, and particular reference will be made to the use of steel mill holes and hydraulic roof supports. The gravel backfill line, which is operated both by gravity and hydraulically, is described. The paper mentions some of the operational problems, discusses the feasibility of longwall mining and presents the information obtained from stope testing."

Jan 1, 1966

By A. M. Christie

Acknowledgements The following account has been compiled mainly from records and maps of Eldorado Mining and Refining (1944), Limited, hereinafter called the Crown Company. This work was done under the supervision first of R. F. Murphy, Chief Geologist, and later of E. B. Gillanders, Eldorado Mine Manager and Manager of Eldorado Exploration Division. W. F. James and B. S. W. Buffam are consulting geologists. Since 1946, S. N. Kesten has supervised geological work for the Company in the Goldfields area. Where maps of Eldorado properties have been included in this paper, the name of the geologist who examined the property is acknowledged on the map. Outline of General Geology The geology of the area is described in the Goldfields and Martin Lake preliminary maps of the Geological Survey and accompanying Paper 49-17. In brief, the Tazin series of Precambrian age, consisting mainly of sediments with minor interbedded volcanics and basic intrusives, is intruded and replaced by granite, now generally gneissic. The late-Precambrian Athabaska series of conglomerate and arkose, with interbedded basalt and andesite flows, rests unconformably on the older rocks. All these rocks are cut by small diabase dykes. The geological terms used in this paper and in the accompanying figures are standard with the exception of the term 'mafic rocks'. These include all the basic or dark coloured rocks of the Tazin group, such as amphibolites, biotite schists, and chlorite-epidote rocks (greenstones), whether they be of extrusive, intrusive, or sedimentary origin.

Jan 1, 1949

By M. E. Holuszko

A research program has been carried out at the Mining Department of the University of British Columbia to study the effect of wettability of coal on its handleability and bulk density. The effect of moisture content on the bulk density of coal was found to be more pronounced for hydrophilic coals than for hydrophopbic ones. Altering wettability of coal surface leads to different effects of moisture on bulk density. The samples were studied at different fine fractions content, and it was shown that there was no effect of increased content of fines on the bulk density for hydrophobic coals, while for hydrophilic coals this effect was very significant. It was shown that the moisture content at which the lowest bulk density was reached coincides with the critical moisture content for studied samples, as determined from handleability tests using Durham Cone method. This critical moisture is the moisture content at which a sudden deterioration of coal handleability occurs. Based on the bulk density and handleability tests, the flow theory of moist coal is proposed.

Jan 1, 2006

By P. A. Crane, N. Shirley, Aung Moe, H. M. Nicholson, D. Kan

Kazakhstan’s first commercial copper-leach solvent extraction-electrowinning plant, Central Asia Metals’ Kounrad project, was commissioned in April 2012. Exploiting low grade waste stockpiles produced during Soviet era open pit mining, a 10,000 tpa copper cathode plant was designed, constructed and commissioned within 18 months. Overcoming initial challenges with a workforce unfamiliar with the technology and with extensive periods of sub-zero conditions during winter the project has consistently met targets and produced high quality copper cathodes at cash costs of less than US$1/lb. Challenges encountered during the first two years of operation are described and future plans briefly discussed.

Jan 1, 2014

By M. Massinaei, M. R. Yarahmadi, S. Zeidabadi, M. Oliazadeh

"Although the majority of new flotation column installations continue to be for cleaning or recleaning, an increasing number of flotation projects are specifying columns for roughing or scavenging duties. NICICO has recently installed flotation columns operating in rougher, cleaner and re-cleaner circuits at three new copper concentrators; Miduk, Sungun and Sarcheshmeh. Miduk is probably one of the unique operations that use flotation columns in a rougher circuit. The Miduk rougher circuit comprises five CISA parallel columns. The rougher concentrate constitutes 88% of final concentrate and reports to concentrate thickener. The rougher tailings are scavenged with ten 50 m3 mechanical cells. The scavenger concentrate is then reground and cleaned in three 3.2 m columns in parallel. The cleaner tailings are scavenged in six 50 m37mechanical cells. The cleaner tailings along with the rougher scavenger constitute final tailings.In Sarcheshmeh, the cleaner concentrate is re-cleaned in a column. The column tailings are sent back to the cleaning circuit and the concentrate is reported to the concentrate thickener.This paper reviews performance details of the flotation columns utilized in rougher circuits at Miduk and compares their metallurgical performances in an industrial scale with columns at cleaning circuits for copper flotation. Practical limitations for applying the flotation columns in rougher circuits will be discussed in details.INTRODUCTIONThe use of flotation columns has grown rapidly since the first successful commercial application at Mines Gaspe, where columns were used in a cleaning circuit to float molybdenite. Early applications of columns were restricted to replacing or adding final cleaning stages in existing circuits. Columns can achieve superior cleaning as compared to conventional cells due to their ability to support a large froth depth and the use of water for washing froth. Wash water travels down through the froth and crosses the pulp/froth interface, replaces the entrained particles reporting to the froth from pulp and improve the concentrate grade."

Jan 1, 2011

By John Kruse, Sethu Raman, Dave Tenney

The Cullaton Lake B-Zone gold mine was the first gold producer in the Kaminak Subprovince of the Canadian Shield . Located approximately 650 km north of Thompson. Manitoba, the mine produced 77,783 ounces of gold and 5,564 ounces of sil ver from 251 ,236 tons of ore during 1981-84 period. The depos it is a small , structurally controlled , stratabound orebody in an Archean iron formation. Most gold occurs in sulphide and silicate fac ies. Based on new ev idence, the depos it is interpreted to have fo rmed by remobilization of syngenetic low-grade gold mineralization in the iron fo rmation in a favoura ble fold structure. The concept and methods developed at the mine have been successfull y applied in the discovery of new deposits in the area. One of the concepts. which link Archean and Proterozoic mineralization. may have wider applications in the search fo r gold deposi ts elsewhere in Canada .

Jan 1, 1986

By D. Berkley

Off-gas systems often become the limiting factor in production increase and environmental projects. Any upgrade or new off-gas project needs to address control instability issues, instabilities that can result in safety hazards, significant loss of system capacity and/or emissions to the environment [1]. In addition, the design engineer must optimize system configuration and equipment size for the new operating conditions, to have a technically feasible and economically viable project. Dynamic simulations can be used for addressing both the control stability and the design optimization issues. This paper illustrates how the dynamic simulation of transient processes and of their control system can be used in "real life" situations for these purposes, presenting the example of an electric furnace off-gas system design.

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