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By M. Dupuis

In the present study, the heat balance of the Hirakud smelter aluminium reduction cell has been accurately assessed using only a surface thermocouple and a pyrometer, As it is well known that using a single linear or quadratic relationship to estimate the heat flux from the measured surface temperature does not provide the accuracy required to close the cell heat balance, this approach was not used in this study, Instead, the fundamental natural convection and radiation heat flux equations were used systematically for each measurement point, Practically, this means that the ambient air temperature and at least one ambient radiative temperature must also be known in addition to the surface temperature for each measurement point. Sometimes, the radiative heat flux could not be accurately estimated using a single ambient radiative temperature, In those cases, a more accurate estimation based on two ambient radiative temperatures and corresponding view factors has been used instead, It turns out that although at least three temperature measurements are required to estimate a single heat flux, it takes a lot less time to make those temperature measurements using a pyrometer than directly measuring the heat flux using an expensive heat flux meter, Furthermore, no loss in accuracy was detected when using this approach as the cell heat balance could be closed within 5%, the level of accuracy typical of cell heat balance assessment using heat flux meter.

Jan 1, 2004

By S. Foged

Umicore and MWH jointly demonstrated that mechanical dewatering of goethite and neutralised tailings significantly increased the life of a 30 ha tailings pond and improved the operation of the pond. Umicore operates one of its zinc production plants in Balen, Belgium. As part of its production process, an excess of neutralised and goethite¬containing tailings is generated. These have historically been stored inside large lined ponds. As the storage area of the current goethite pond was nearing its capacity, Umicore studied the potential for an extension to the existing embankment. However, this extension would face intense regulatory scrutiny, because the environmental and safety impacts were considered important. Together with Umicore, MWH suggested and investigated an alternative treatment approach consisting of mechanical dewatering prior to storage. A feasibility study was prepared where wet storage was compared to dry storage. Differences in safety risks, environmental impacts and economic costs were outlined. The study demonstrated that the life of the tailings pond could be increased from 6 to 22 years, seriously reducing the environmental impacts and safety risks at no significantly higher cost than would have been incurred with the continued operation of the existing pond. The results of the study are presented in this paper.

Jan 1, 2006

By F. Awotwe-Appiah, P. Koshy, J. Dankwah, J. R. Dankwah

This research investigates the generation of an effective carbonaceous material from waste ‘pure water sachets’ and their subsequent utilisation as reductants for the reduction of the Opon Mansi iron ore. Composite pellets of Opon Mansi iron ore and pulverised carbonaceous material generated from waste pure water sachets were heated from room temperature to 1200 °C in a gas fired furnace for seventy minutes. The reduced pellet was analysed chemically for its oxygen and carbon content using a LECO Oxygen/Nitrogen and LECO Carbon/Sulphur analysers, respectively. It was observed that nuggets of metallic iron were readily produced with the carbonaceous materials acting as an effective reductant and source of chemical energy. XRD analysis of waste ‘pure water sachets’ revealed that the polymer was semi-crystalline with peaks that were identical to those of high density polyethylene (HDPE). Gas emission behaviour of the iron ore-PWS pellet was studied in a horizontal tube furnace at 1200 °C using an infrared gas analyser; the results revealed an exhaust gas rich in the reducing gases CO and CH4 along with CO2.

Jan 1, 2015

By L. D. Haig

"The Texada Mill is a unique iron operation producing High Grade sinter iron concentrate and a by-product copper, gold, silver concentrate. The plant is complex and extremely flexible to handle the many varieties of ore. Two iron concentrates are made and blended. A coarse iron concentrate from primary grinding and a fine concentrate after rougher flotation to remove all the sulphides.All the tailings from iron processing are collected, dewatered, reground and floated for additional copper recovery.The entire milling operation has been carried out in all sea water for seven years and mixtures of sea, fresh, and reclaimed water for ten years prior to that.A very stable float results from the use of sea water at the natural pH8. Reagent Consumption is lower and Metallic Corrosion of mill liners and grinding media is actually less than local fresh water or mixtures of fresh and sea water.Marine growth in pipe lines can be periodically removed by violently bubbling high pressure air up through the water filled mains.Location:Texada Mines is located on tide water on the west side of Texada Island 100 miles northwest of Vancouver, B. C.The Island is served by a 30 car ferry, tug and barge and a scheduled air service from Vancouver to a company maintained air strip near the mine.The climate is moderate with about 30 inches of rain during the winter and relatively dry summers."

Jan 1, 1974

By J. A. Harle

Introduction When considering power in Alberta, there automatically come to mind ideas of either hydro or thermal generation, leaving in one's thought an uncertainty as to which one would propose. There is frequently an obvious source of power in some locations on our fastflowing rivers, the major possibilities being described in the report on Surface Water Supply and Water Power of Alberta issued by the Alberta Government in 1948, but it must be realised when reading that report that the sites so described will require extensive geological and other surveys before they can be exploited, and account must be taken also of the transmission distances involved in each instance. From a conservation point of view, where water power can be economically developed and power transmitted to the load centres, this should be done, and our thermal resources should be husbanded for our coming generations, especially if our water resources are falling owing to glacial shrinkage.

Jan 1, 1951

By A. A. Paoli

The selection of a mining plant for carrying on development work presents many problems distinct in themselves, and affected by various local factors. In this paper, the writer proposes outlining and discussing in some detail the chief factors governing the economic selection of such plants. This will be followed by an enumeration of the underground and surface plant required for carrying on several hypothetical exploratory and mining operations. Where it is impossible or not convenient to obtain hydro-electric power, and where wood for fuel is scarce, we now find oil engines being used. A 100 h.p. oil engine, such as would be required to operate a three-drill air compressor, consumes approximately five Imperial gallons of fuel-oil per hour at full load. On the basis of a 60 per cent load factor, this gives, for eight hours' operation, a probable actual consumption of twenty-four Imperial gallons.

Jan 1, 1929

By H. B. Merlin

"The past demands for energy and the contributions by the major sources are shown for the world and regions, and for Canada. Three forecasts of future demand are presented. By the year 2000, the world will be consuming energy at a rate of 670-700 x 1015 Btu/year. Canada's rate is estimated at 20 x 1015 Btu/year. Electricity will increase its portion of energy from 7.5 per cent to 15 per cent, and more than 40 per cent of the primary energy w1ll. be required to generate 1t. World, regional and Canad1an forecasts are g1ven for total electricity generated and for electricity generated in nuclear stations. The integral world requirement for energy by the year 2000 will be over 12 x 10 18 Btu. Current recoverable fossil and hydro reserves are about 18 x 1018 Btu. The total reserves are estimated to be seven times greater.World production of electricity in nuclear stations by the year 2000 will be almost three times the electricity produced in the world today. The amount of fuel consumed in generating this electricity will depend upon the types and mix of reactors installed. The heavy water reactors, alone or in conjunction with fast breeders and liquid fuel reactors, are the most efficient users of uranium and thorium resources. The heavy water reactors are also the most efficient producers of plutonium which will be required as fuel for fast breeders."

Jan 1, 1969

By R. D. Lindsay

"Pamour Porcupine Mines, Limited is involved in the mining, milling and primary refining of various gold, gold - copper and refractory gold ores. Pamour operates five mines in the Porcupine Mining District of Ontario, and two 2,550 t/d milling facilities.Both metallurgical facilities use conventional cyanidation technology including zinc cementation for precipitation of gold and silver from solution. The precipitation process, as applied to clarified leach solutions (less than 1 ppm suspended solids) at Pamour is called the Merrill - Crowe process. Precipitates from both milling operations are treated at Pamour's Area Refinery. Schumacher precipitates, unlike Pamour No. 1, require an ''Acid Treatment Stage"" prior to refining to remove the high contained copper. This is accomplished by leaching the precipitates initiallv with sulphuric acid to remove zinc and then with sulphuric acid and manganese dioxide to dissolve copper. Refining procedures after ''Acid Treatment"" are essentially the same for both precipitates.The following considerations highlight the basic principals applied to refining cyanidation precipitates at Pamour, including:"

Jan 1, 1986

By D. Chakravarty, D. Dutta, B. Samanta, S. Patteti

"This paper presents the mixed spectral behaviour of iron ores from deposits in Gua, India. Spectral signatures of powder samples and their two-component mixtures were generated by spectro - radiometry. Spectra were divided into continuum and absorption components. A modified Gaussian model was used to extract subtle features from the absorption components of the spectra. A linear unmixing model (LUM) applied to estimate minerals from the spectra of mixed powder samples indicated that this model achieved an R2 value of 0.88. The LUM was then applied to estimate the abundance of ores from a hyperspectral satellite image of the deposit area.RÉSUMÉ Le présent article montre le comportement spectral mixte de minerais de fer de gisements à Gua, en Inde. Les signatures spectrales d’échantillons de poudres et leurs mélanges à deux composantes ont été générés par spectroradiométrie. Les spectres ont été divisés en composantes de continuum et d’absorption. Un modèle gaussien modifié a été utilisé pour extraire des caractéristiques subtiles des composantes d’absorption des spectres. Un modèle de démélange linéaire, appliqué pour estimer les minéraux dans le spectre des échantillons de poudres mixtes, indique que ce modèle a atteint une valeur R2 de 0,88. Le modèle de démélange linéaire a ensuite été appliqué pour estimer la quantité de minerai à partir d’une image satellite hyperspectrale du secteur du gisement."

Jan 1, 2015

By Roxanne Scott

Outline ? Overview of Community Investment in the Mining Sector ? Emerging Good Practice: ?Strategic Integrated Community Investment? ? Assessing Local Context: ? Institutional Assessment ? Partnership Assessment Approaches to Community Investment Isolation: No proactive engagement in community development Ad hoc philanthropy: small infrastructure, sponsorships, donations Strategic philanthropy: Community proposes options for development Company decides what to do and carries it out, e.g. building schools, health posts, roads Strategic integrated community investment: ? Aligned with government/community development goals and priorities ? Communities and government involved in decisions and execution ? Focused on training and capacity building ? Partnerships ? Continuation in absence of company support Measured returns on investment

May 1, 2010

By J. E. Armstrong

"IntroductionT'HE PRODUCTION of gravel and sand may be considered to be the major mining operation in the Lower Fraser Valley of British Columbia. At least thirty pits are in operation with a yearly production probably in excess of two million yards and a value in excess of one million five hundred thousand dollars before crushing, washing, and sizing. The value of the finished products would probably be double the above figure.Since 1949, the writer and his co-workers have been engaged in the geological investigation of the Lower Fraser valley and adjoining Coast mountains for the Geological Survey of Canada. The study, which is not yet completed, includes both bed-rock geology and geology of the unconsolidated sediments lying above bed-rock. In a rapidly expanding industrial area, .an advance knowledge of the geology may• greatly aid in future 'planning, and in many cases may .prevent not only the wastage of large sums of money, 'but possible disaster. Some of the present and future applications in which geological information in the Lower Fraser valley should be of value are as follows: the development of domestic, irrigation, industrial, and municipal groundwater supplies; drainage for industrial sites,, roadbeds, and farmlands; flood control along the Fraser river and smaller streams in the area; the location of dam sites, of major tunnels for water supply •and sewage, of road-beds, of foundation sites for large buildings .and other engineering undertakings in which geology may aid; the evaluation of oil and gas •possibilities; the production of building stone; and the production of sand and gravel, the subject with which this paper is primarily concerned."

Jan 1, 1953

By John H. Low

Introduction Despite the fact that the .association of magnetite with chrysotile asbestos in the parent producing area of the world, the Thetford Mines - Black Lake area, has been recognized since the ores of that region were first known, magnetic methods were not extensively employed in exploration for asbestos until about the beginning of 1949. Since then, large areas of Ontario, Quebec, and the eastern United States have been prospected both by aeromagnetic and conventional ground magnetic methods. Prior to 1949, a limited amount of magnetic work had been done, notably that of A.H. Miller (1, pp. 184-186), which was carried out in conjunction with the geological survey of the Thetford area by H. C. Cooke (2) in the years of 1930 to 1932. At that time, Miller pointed out that the occurrence of asbestos is associated with very large magnetic 'anomalies' and that, within the Pennington dyke, an area of asbestos- bearing peridotite could be distinguished, by the anomalies, from adjacent areas of non-asbestos ?-bearing peridotite. Since he .also observed large anomalies in what were believed to be ?barren areas, Miller concluded, however, that the magnetometer could hardly be of much or any value in the direct location of asbestos War .and post-war demands on known reserves of asbestos ore, however, stimulated the search for new deposits, and an economical and rapid method of directing speculative drilling was most desirable.

Jan 1, 1951

By G. Warren

"In the past, smelting and refining of the precious metals recovered from ore has been generally looked upon as a small and relatively minor component of the business of gold mining. This is not surprising when one considers that the manpower, space and capital components of a gold refinery at an operating mine can be several orders of magnitude smaller than other unit operations at the same location. This philosophy is changing however, as economic and environmental pressure are forcing a re-evaluation of all aspects of gold mining and milling.This paper describes and evaluates three furnace technologies available and used by precious metal operators. The operation of arc, induction, and reverberatory furnaces are discussed and their strengths and weaknesses with respect to capital cost, impurity removal, slag quality, and environmental concerns highlighted.INTRODUCTIONIn the past, smelting and refining of precious metals recovered from ore has been generally looked upon as a small and relatively minor component of the business of gold mining. This is not surprising when one considers that the manpower, space, and capital components of a gold refinery at an operating mine can be several orders of magnitude smaller than other unit operations at the same location. Generally, gold producers will spend a great deal of effort to squeeze the last drop of efficiency out of a leach or grinding circuit via simulation or testwork but will design and build the refinery based upon past practices or industry standards. That past practices or industry standards will provide a functional refinery is undisputed; that this philosophy achieves the efficiencies that are possible or demanded in other plant operations is debatable.Environmental and worker hygiene requirements are considerations as well. Pollution control equipment can become a substantial contributor to both the capital and operating costs of a refinery and furnace selection has a marked influence upon the type and cost of this equipment. Slag characteristics and subsequent processing options available also play a role in furnace selection as precious metal slag losses and the recovery effort can greatly influence the cost / benefit analysis of a particular technology."

Jan 1, 2001

By Mostafa Benzaazoua, Emilie Ré, Raphaël Mermillod-Blondin, Hassan Bouzahzah, Jean-François Wilhelmy, University of Québec in Abitibi-Témiscamingue

"We analyzed two copper and lead flotation concentrates from the LaRonde mill using MLA technology (Mineral Liberation Analyzer) to identify the contaminants and to quantify their size and liberation. The MLA mineral quantification was compared with traditional mineralogical techniques (Scanning Electron Microscopy, Optical Microscopy, X-Ray Diffraction and Chemistry). The accuracy of MLA data was then quantify in application to metallurgical decision (mineral identification, mineral quantification, particle sizing and liberation quantification). We prepared five well-known materials from pure minerals and analysed them by MLA. MLA concentrates analyses showed the lead concentrate is mainly contaminated by pyrite and sphalerite. These minerals are liberated above 70 % and present a floatable size around 15 to 35 µm. Surface activation by dissolved lead from galena is therefore assumed for these contaminants. The analyses of the known samples show that mineral quantification and size distribution given by the MLA are consistent with the chemical analyses and the laser particle sizer. The liberation measurement is affected by the stereological effect. Modelling quantifies the overestimation of the particle liberation. Based on the modelling, the stereological shift on liberation should not impact metallurgical conclusions on the concentrate contaminations.INTRODUCTIONTo face the diversity of mineral processing challenges, the process mineralogy includes phase quantification, measurement of mineral size, liberation by exposure and by grade, association, surface contact proportion and texture. In the last decades, two SEM commercial tools emerged: MLA and QEMSCAN R. Both are based on specific combinations of backscattered electrons and X-ray images as well as image analysis routines developed at CANMET (Petruk & Pinard, 1976, Petruk, 1989), CSIRO (Frost, O'Hara, Suddaby, Grant, Reid, Wilson & Zuiderwyk, 1977, Reid, Gottlieb, MacDonald, & Miller, 1984) and JKMRC (Hall, 1977, Gu & Sugden, 1995). Recently, TIMA (TESCAN) and Mineralogic MiningR (ZEISS) supplied automated mineralogy for mining industry (Bouzahzah, Benzaazoua, Graham & Cropp, 2015, Gottlieb & Dosbaba, 2015a). In parallel, home-made routine were developped to resolve mineralogy challenges in mineral process but also in geometallurgy and mining environment (Kahn, Mano, & Tassinari, 2002, Knight, Klassen & Hunt, 2002, Mermillod-Blondin, Benzaazoua, Kongolo, de Donato, Bussiere & Marion, 2011, Hunt & Bradshaw, 2015). SEM mineralogy become essential to operation by setting units on mine sites (MacDonald, Latti, Adair, Bradshaw, & Dunn, 2011, Goergen et al., 2013, Dobbe et al., 2014, Gottlieb & Dosbaba, 2015b)."

Jan 1, 2016

OVERVIEW OF PRESENTATION ? What is LMI ? Who uses LMI and how? ? Value of LMI to the Mining Industry ? Mining Industry Workforce Information Network (MIWIN) ? The Challenge: Forecasting the future in uncertain times ? Results: Hiring requirements in the next decade ? Results: Occupational information ? Next steps

May 1, 2009

By F. C. Robles Hernandez

This paper presents the results of the electromagnetic semi-solid treatment of the 319 aluminum foundry alloy, Various levels of structure modification were achieved controlling the AC current used to create the Electromagnetic Field, thus manipulating the intensity of the field, The level of grain refinement, partial modification of the Al-Si eutectic, as well as cellular dendrites were observed, A quantitative analysis of the structure was performed using Image Analysis (IA) techniques. In addition a novel Thermal Analysis methodology was developed for the on-line determination of the microstructure modification level.

Jan 1, 2004

By Jing Li, Weiqiang Lai, Joe Zhou, Jiezhen Ma, Shuibo Chen, Ashele Copper Company, Feng Gao, Guofu Feng

"Copper-zinc ores often contain gold and silver, which can be recovered into copper concentrate by flotation as by-product. The challenges for operations that produce copper, zinc, gold and silver are the separation of copper and zinc and the low grade of precious metals. Ashele copper-zinc ore in north China contains 2.38% Cu, 0.69% Zn, 0.21 g/t Au and 18.10 g/t Ag and the plant produces copper and zinc concentrates, with gold and silver being recovered into copper concentrate. Copper occurs mainly as chalcopyrite and Zn occurs as sphalerite. Copper is well recovered with a recovery of over 94%. However, the recovery of Zn is substantially low (around 50%) due to fine grain size of sphalerite. In addition, gold recovery is much lower than expected and only 33% of gold in the flotation feed was recovered. The grade of gold in copper concentrate is also lower than the required payable grade (1.0 g/t). To determine the cause for lower Zn and Au recoveries, a plant survey program was conducted on the operation. The information acquired shows that the loss of Zn was mainly in the copper concentrates (accounting for approximately 38% of the head assay); of which, 24% was liberated, 8.5% was associated with chalcopyrite and 4.6% was associated with pyrite, indicating that the separation of copper and zinc was the main cause for the Zn loss, with liberation being the second cause for Zn loss. Future effort in improving Zn recovery should be focused on the separation of zinc from copper. Gold in the ore occurs as both microscopic gold and submicroscopic gold, accounting for 36% and 64% of the head assay, respectively. Microscopic gold occurs mainly as native gold and electrum; it is relatively coarse with a grain size of 10 to 240 µm and a large portion can be recovered by gravity. Submicroscopic gold was mainly carried by pyrite (accounting for 38%), and to a less extent, by tennantite (15%) and chalcopyrite (10%). Gold in sphalerite is nominal (1%). It is suggested that more coarse gold and tennantite be recovered and a gold recovery increase can then be achieved to obtain a copper concentrate with over 1.0 g/t Au through flowsheet optimization. Gravity concentration should be investigated and may be worth added into the existing flowsheet to maximum the gold recovery and grade.INTRODUCTIONCopper-zinc ores containing gold and silver is a subtype of polymetallic sulphide ores. Unlike porphyry copper sulphide ores and iron-oxide copper-gold ores, this type of ores often contains substantial amounts of zinc and lead. Polymetallic sulphide ores are mainly distributed in Canada, such as at the LaRonde and Horne deposits. Other examples include Mt. Morgan in Australia and Boliden in Sweden. Globally, production and reserves from gold-rich VMS deposits account for 1370 t gold. This is equivalent to 1% of the world production and reserves, whereas the Canadian total for gold-rich VMS deposits is 870 t, representing close to 10 % of Canadian production and reserves (Gosselin & Dube, 2005a, 2005b). Flotation is the principal process for processing the copper-zinc sulphides ores, for subsequent smelting, roasting, or hydrometallurgical treatment. Oxidized copper-zinc ores can also be processed using leaching technology. For example, at LaRonde operation (a Cu-Zn-Pb ore containing 3-4 g/t Au and 60-100 g/t Ag) the flowsheet consists mainly of a copper flotation circuit and a zinc flotation circuit followed by a cyanidation process of flotation tails. The precious metals are recovered with copper concentrate, zinc concentrate and cyanidation of zinc tails via Merrill Crowe precipitation (Zhou et al., 2005)."

Jan 1, 2016

By J. A. Finch, A. R. Laplante, R. Espinosa-Gomez

"The Niobec concentrator rejects up to /5% of the Nb as slimes (-10u.m). The recovery of Nb from these slimes by column flotation is being studied. An essential condition for selective flotation is slimes dispersion. A particle size analyzer, the Sedigraph 5000D, was used to monitor dispersion in plant waters with combinations of organic and inorganic dispersants and flotation reagents. Flotation reagents were particularly detrimental to dispersion with sodium silicate. The best dispersion conditions were selected for column flotation tests. These tests revealed that reagent combination had a pronounced effect on froth stability. Careful frother selection achieved good froth stability under conditions of good dispersion. Plant water increased the required dispersant concentration causing mineral depression.IntroductionSlimes (-10 u.m) rejected at Niobec contain up to 15070 of the over-all Nb content . Recovery of Nb from these slimes would significantly increase over-all recovery. A suggested recovery route involves two phases: (1) carbonate flotation (to remove most of the carbonates) depressing silicates and pyrochlore (as currently done at Niobec); and (2) selective (direct) pyrochlore flotation from the silicates. Phase 2 has been addressed and several routes to achieve selective flotation are available. Phase I was attempted with the selective reagent scheme used at Niobec but a considerable amount of pyrochlore floated with the carbonates due to poor slimes dispersion."

Jan 1, 1987

By E. Herrera Alarcón, L. Mariscal Samaniego

The Teniente Converter (wet charge type) was commissioned in august 1995 and was designed to smelt 744 tpd (metric tons per day) of dry copper concentrates. Its products are white metal (73% Cu) that is sent to the Peirce Smith converters, slag that is cleaned in Reverberatory Furnaces and the process gases that are sent to the Sulfuric Acid Plant. Since its start up, the Teniente Converter smelting capacity was increased 1.6 times, from 800 tpd to 1,280 tpd using 33% oxygen-enriched air, and reaching an operative availability of 97%. By the other hand its campaigns have reached a record duration of 530 days without hot patching tuyeres and a partial refractory lining repair in the last four campaigns. This paper describes the most relevant improvements, as well as the strategies that had been used to reach these achievements.

Jan 1, 2007

By R. T. Elworthy

Canada ranks second in the list of world consumers of natural gas. In 1923 our production was nearly fifteen million thousand cubic feet valued at $5,800,000. Our output, however, appears very small compared with that of the United States, which in 1923 totalled over one thousand and eight million cubic feet, valued at $240,000,000. Natural gas is found in commercial quantities in three? provinces in Canada. New Brunswick: Natural gas in New Brunswick has been utilized commercially only since 1912,although the investigation of oil and gas possibilities of the province commenced as early as 1859. The annual production is a little more than one-twentieth of the total Canadian production and remains fairly constant from year to year. Ontario: In Ontario the earliest gas wells were drilled in Essex and Welland counties between the years 1885 and 1890. On account of the small demand in Canada the cities of Detroit and Buffalo were supplied with large quantities of gas from these wells, but this export was curtailed in 1898 and finally ceased in 1900. The production of natural gas in Ontario, mainly from fields in Lambton, Kent, Essex, Norfolk, Haldimand and Welland counties, increased rapidly from 1900 until the peak was reached in 1917, when over nineteen million thousand cubic feet valued at $3,641,587 was consumed.

Jan 1, 1925