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By C. R. Ross

"THE ASSESSMENT of pneumoconiosis-producing dusts in mines and other industries is usually undertaken for one or more of three reasons: (1) To compare dust exposures at particular operations with standards of permissible dustiness in order that hazards may be evaluated and preventive procedures initiated where required.(2) To study particular operations with the objective of improving dust control devices or procedures by locating dust sources. (3) To obtain data which, along with the results of medical investigations, may assist in understanding the causes of dust-induced diseases or aid in the establishment of permissible standards of dustiness. Most dust measurements are made for the first of these reasons -to evaluate dust hazards so that they may be controlled. For this purpose, four quite different assessment techniques have been in widespread use for many years. One of these is based on the konimeter, an instrument familiar to most .Canadian mining men; a second on the impinger, which is also widely used in Canada, and almost exclusively so in the United States; a third on the thermal precipitator, used extensively in Britain and South Africa; and a fourth on the tyndallometer, a light-scattering instrument used in Germany."

Jan 1, 1960

By G. W. Poling

Sedimentation behaviour of siliceous mill tailings derived from a magnetite-chalcopyrite ore in fresh water, fresh water - sea water mixtures and full-salinity sea waters are compared. Results of batch settling tests are presented in the form of settling curves and solids flux curves. The addition of a few per cent of sea water markedly enhanced the zone sedimentation rate due to particle agglomeration caused by a reduction in zeta potential of the suspended solids. The presence of a small amount of residual, previously magnetized magnetite in the tailings also enhanced agglomeration and sedimentation. The significance of these results to submarine disposal of mill tailings is discussed.

Jan 1, 1973

By I. Demers

The abandoned Manitou mine site covers an area of approximately 190 ha near Val d?Or, Quebec. This old site has been generating acid mine drainage for several decades. In 2006, a partnership was established between the Quebec Ministry of Ressources Naturelles (MRN) and Agnico-Eagle Mines to reclaim the Manitou site using tailings from the nearby Goldex mine. These neutral tailings were to be deposited on top of the Manitou site. An extensive study was performed to evaluate specific reclamation scenarios to control acid mine drainage using Goldex tailings as cover material. The article first describes the global approach used for this evaluation, which includes in-situ hydrogeological monitoring, tailings characterization, laboratory column tests, and numerical modelling. Of the thirteen column tests, three were conducted to evaluate the parameters affecting the performance of covers made of Goldex tailings placed over the spillage area of the Manitou site. Geochemical and hydrogeological parameters were assessed during the leaching column tests for almost two years. The tests aimed at evaluating the effect of water table level and monolayer cover thickness on the overall performance. The testing procedure involved monthly leaching and measurement of geochemical parameters. Results indicate that water table position is the most important factor affecting the monolayer cover performance to control AMD. Based on these results, it was established that the water table must be located near the interface between the Goldex and Manitou tailings to effectively reduce AMD generation. Cover thickness also has an impact on cover performance, which is however less significant than the water table position. The testing scenario with a water table located at the interface with a one-meter Goldex tailings cover showed progressive improvement in effluent quality.

Aug 1, 2013

By James A. Robertson

"This paper is the result of a continuing investigation begun in 1953 by government geologists and mining companies. Previous work is reviewed and the development of several stratigraphic nomenclatures and correlation schemes is traced, culminating with the interim report of the Federal-Provincial Committee on Huronian Stratigraphy formed in 1966.The stratigraphy, structure and correlation of the Huronian rocks of the Blind River area and the region between Sault Ste. Marie and Sudbury are reviewed. The area is underlain by three Precambrian units: (1) the Archean greenstones and granites, (2) the Huronian sedimentary and volcanic rocks and (3) the post-Huronian intrusive rocks. The Huronian rocks, largely quartzite and conglomerate with greywackes, argillites and carbonates, were laid down in shallow water transgressing over the eroded Archean basement. Thickness and facies changes indicate a northwesterly source, northerly overlap and deposition controlled by basement topography. Polymictic conglomerates, occurring at least at three horizons, represent tillites and are associated with varvites with dropped clasts. These are best developed in the Gowganda formation, which varies from a continental glacial environment in the north to a marine glacial environment in the southeast.There were at least three phases of post-Huronian igneous activity, probably related to several periods or phases of late Precambrian deformation and metamorphism: (1) sills of Nipissing diabase and rather younger diabase dikes; (2) the Cutler Granite and Croker Island Complex; and (3) dikes of Keweenawan olivine diabase.Copper mineralization is associated with the Nipissing diabase. The uranium ores are found in pyritic quartz-pebble conglomerate near the Huronian Archean unconformity, particularly in ancient valleys; they are considered to be placer deposits modified by later events. Uranium production from the Blind River camp to the end of 1966 was 128,160,096 pounds U308 valued at $1,203,840,848 derived from 56,077,179 tons of ore grading 0.11 per cent U308.Within the Blind River and adjacent areas, future discoveries will probably be the result of costly systematic deep-drilling programs accompanied by detailed geologic studies of the type carried out by oil companies and probably computer-oriented."

Jan 1, 1969

By K. A. Clark

SEPARATION of the oil from the bituminons sands of the Athabaska area of Alberta has been a subject of study by the Research Council of Alberta. The results of the study have been published in the Annual Reports of the Council. However, the last Annual Report in which there is mention of bituminons sand separation is that for 1934. The attention that is being directed toward the bituminons sands at the present time calls for an up-to-date summary of the work of the Research Council of Alberta on the hot-water separation process. STATEMENT OF FUNDAMENTALS OF HOT-WATER PROCESS Studies of the hot-water separation process have been largely empirical in nature. The objective sought has been a complete recovery of oil from the sand in the form of a separated oil which, itself, is free from mineral matter. Various procedures have been tried in the hope of attaining this objective and a very considerable mass of observations and background of experience have been acquired. lt is rime that a theory for hot-water separation should commence to emerge. As a start toward the formulation of such a theory, the statements which follow regarding the constitution of bituminons sand and its reactions with water and air are presented. It is not pretended that they are entirely correct, but it is believed that they lie not far from the truth. (1) Bituminons sand is an aggregate of sand, clay, oil, and water. The sand consists mainly of quartz particles of 100 ta 200 mesh size and smaller, but also of particles of other minerais including mica, rutile, ilmenite, tour-maline, zircon, spinel, garnet, pyrite, and lignite. Clay occurs interbedded with the bituminons sand, of which, also, it is a constituent. lronstone nodules of all sizes up to eight inches in diameter are likely to be present in the bituminons sand beds. The oil is viscous, naphthenic, and of a specific gravity slightly greater than that of water. The oil content ranges up to, and sometimes even exceeds, 17 per cent by weight. Rich bituminons sand from beds not invaded by water has a water content of 3 to 5 per cent by weight. The water is probably present as a film around the sand particles. The oil surrounds the moist sand grains as an envelope. (2) Water wets quartz and other siliceous minerals more readily than does mineral oil. Consequently, water tends to displace the oil film surrounding the quartz and other siliceous particles when the bituminons sand is mixed with water. Whether the oil is completely displaced depends on the properties of the water. That is to say, the materials dissolved or suspended in the water modify its wetting properties.

Jan 1, 1944

By P. Langlois, G. Labonté, J. J. Barrett, J. Holmes

"The Voisey’s Bay mill processes a high-grade pentlandite and chalcopyrite ore in a largely pyrrhotite/troilite matrix. From 1994 to 1997, circuit development focused on making a 14% nickel concentrate. When flowsheet development resumed in 2001, the target grade was raised to 20% ni. initially triethylene tetramine and sulfite pyrrhotite depressants were used in a lime circuit, but by recycling process water and the contained thiosalts, the required nickel grade was made without depressants. construction of the mill was fast-tracked, with start-up in september 2005. ramp-up was faster than other recent nickel installations, with tonnage being limited by concentrate dewatering due to higher-thanexpected ore grades.RÉSUMÉ l’usine de traitement de Voisey’s Bay traite un minerai à teneur élevée en pentlandite et chalcopyrite dans une matrice formée surtout de pyrrhotite/troïlite. De 1994 à 1997, le développement du circuit ciblait la production d’un concentré à 14 % de nickel. lorsque le développement du schéma de traitement a été repris en 2001, la teneur cible a été élevée à 20 % de ni. initialement les déprimants triéthylènetétramine et sulfite de la pyrrhotite étaient utilisés dans un circuit à la chaux; cependant, en recyclant l’eau du procédé et les sulfosels qui y sont contenus, la teneur en nickel a été atteinte sans utilisation de déprimants. la construction de l’usine de traitement a été accélérée et elle a démarré en septembre 2005. la mise en opération a été plus rapide que pour d’autres installations récentes de nickel; le tonnage traité étant limité par le séchage du concentré en raison des teneurs de minerai plus élevées que prévu.INTRODUCTIONnickel was discovered on canada’s east coast in the vicinity of Voisey’s Bay, northern labrador, by chislett and Verbiski (Higgins, 2011) while working for Diamond Fields resources in 1993. The ovoid deposit was subsequently delineated in the winter of 1994–1995. By the end of 1995, the ovoid had been well explored, and at that time was thought to have a reserve of at least 30 million tonnes (Mt), with an average grade of 2.83% ni and 2.0% cu (naldrett, singh, Krstic, & li, 2000). Drilling to the east of the ovoid indicated the presence of significant mineralization. in June 1995, inco limited bought a 25% share in the Voisey’s Bay nickel company (VBnc), which was a subsidiary holding company set up by Diamond Fields. inco also bought 8% of Diamond Fields and negotiated the right to sell all the nickel produced from VBnc for 20 years as part of this agreement. in april 1996, inco bought Diamond Fields and acquired the remaining 75% of VBnc shares."

Jan 1, 2017

By H. J. Chalmers

THE H.B. MINE and concentrator are located in the Nelson Mining Division of British Columbia, on the north side of the Sheep Creek valley about seven miles southeast of the town of Salmo. It is an operation of The Consolidated Mining and Smelting Company of Canada, Limited (Cominco), which has its metallurgical plants at Trail, about 25 miles west. The property was originally staked about 1907 by Horton and Benson, whose names are commemorated in the designation "H. B." Up until 1927, a considerable amount of development work was done in the upper levels by various companies. Cominco purchased the ?property in 1927 and carried out intermittent work until 1946. Following this, an extensive surface diamond drilling programme and a subsequent underground exploration were undertaken. Sufficient ore was outlined 'to warrant the construction of a 1,000: ton concentrator. This was started in April, 1952, and completed by the spring of 1953. However, because of adverse base metal market conditions, operation was deferred until May, 1955.

Jan 1, 1957

By M. L. Connolly

Zinc production by Cominco Ltd. began in Trail in 1916 at a rate of 55 metric tonnes per day (t/d) and was increased ,in several increments until now electrowinning capacity approaches 750 t/d. The last increment, 40-t/d high-productivity electrowinning plant, was commissioned in 1974. In this paper, the design and operating experience with both the existing electrowinning plant and the new high-productivity plant are described.

Jan 1, 1977

By D. B. Stewart

In the past few years, much effort has been spent in elucidating the impact of diesel engines on the mine environment. This paper summarizes diesel fundamentals , exhaust emissions and typical tailpipe concentrations. Mine sampling results and an evaluation of exhaust treatment systems are discussed. A review of changes in pollutant concentrations between the tailpipe and the mine exit is made and suggestions are given to reduce operator exposure to diesel contaminants.

Jan 1, 1978

By L. Becze, B. Pierre, S. Di Carlo, G. P. Demopoulos

From January to June 2007, the autoclave production at the Kidd Metallurgical Site was severely affected as a result of plugged discharge lines and extensive precipitation/crystallization of sulphates that caused massive scaling in different autoclave compartments. Work was performed at McGill University to understand the root causes. The crystallization of zinc and ferrous sulphate salts was investigated in terms of solubility measurements. Scale samples were characterized using chemical and mineralogical-spectroscopic analysis. In this paper, following a description of the Kidd zinc pressure leach operation, highlights from this investigation are presented and solutions used to overcome the problem are outlined.

Jan 1, 2008

By K. H. Kretzschmar, M. A. Smith

A brief review of the rapid growth of ACT in Western Canada is presented. It is remarked that this rap-id growth has been accompanied by a heterogeneous approach to design. A more rational and consistent approach is suggested, together with the assumptions on which this approach is based. The operating history of some existing installations is discussed briefly, and conditions necessary for the continued growth of ACT are outlined.

Jan 1, 1960

By G. M. Furnival

A PROGRAMME of structure drilling was commenced in the Southern Alberta Plains in June, 1943, for the purpose of determining the geological structure of the underlying sediments. More than 270 holes have been drilled throughout an area of some 1,800 square miles or 1,000,000 acres (see Figure 1). The Southern Plains of Alberta are covered by a mantle of glacial drift,' at places exceeding 200 feet in thickness. Only where this mantle has been dissected by deep drainage channels is bed-rock exposed to any great extent. Along such channels, surface geological mapping can be conducted to ad- vantage. Accordingly, geological mapping was commenced _in 1942 and continued each season to the present. To supplement this information, a survey of the water wells was carried on in conjunction with the mapping. However, to obtain more positive and evenly distributed structural control throughout the area as a whole and to define more adequately structural trends indicated by the preliminary mapping, it was necessary to resort to the use of drills to penetrate the glacial mantle. Various types of light drills are commonly used for this purpose and provide geological information in the form of drill cuttings, cores, drilling time rates, etc. Correlation of information is generally obtained through comparison of cored sections, drill cuttings, micro-fossils, and drilling time rates. However, in this case the holes were electrologged and correlations were made chiefly by comparison of such logs. The data so obtained is plotted and portrayed in the form of structure contour maps on recognizable stratigraphic horizons and in the form of isopach maps of the recognizable stratigraphic intervals penetrated in the holes. This method had not been widely used in Alberta previously and the technique employed was necessarily developed after the project began.

Jan 1, 1945

"In a continuing investigation into the development of uranium alloys for armament applications, some complex base alloy corn positions were modified by varying the amount of alloying elements and by removing one or two of the alloying elements in turn from the base alloys. These uranium-base alloys were specially formulated in a search for heat-treatable, high-strength, ductile, high-density alloys. All alloys studied were ternary, quaternary or more complex alloys of uranium with molybdenum, zirconium, niobium and vanadium. Each cast alloy was studied under three different heat-treatments, and its mechanical and corrosion properties were determined. It was found that although most of the alloys studied had the hardness and strength required, they were extremely brittle and notch-sensitive under tensile stresses."

Jan 1, 1968

By James D. Bamburak

Total mineral production in Manitoba has averaged C$1 billion over the past ten years. Industrial mineral production has comprised almost 10% of the total, with more than half coming from the aggregate sector. In southeastern Manitoba, tantalum, spodumene and amblygonite concentrates, cesium and rubidium ores, cesium formate, dimension stone and sphagnum peat moss are produced. Gypsum, high-calcium limestone and lime are produced in the Interlake area. Early industrial mineral production consisted of tools and implements, salt and pottery. Historical production has included: salt, building stone, aggregate, lime and dolime, lignite coal, gypsum, natural and Portland cement, calcium bentonite, brick, light-weight aggregate, caustic soda and soda ash, and silica sand. Future industrial mineral production may come from reactivated quarries, pits and wells or from new producers of current commodities. Newproducts may include: stainless steel master alloy, silicon metal, titanium and magnetite, lithium carbonate, float-plate glass and ferrosilicon, "marble" dimension stone, magnesium metal, potash and kaolin.

Jan 1, 2001

By A. Warczok

Metal losses in discard slag are the main factor determining overall recovery. The metals are present both in dissolved form and as matte or metallic inclusions, varying in size from 2 to 1000 µm. Pyrometallurgical slag cleaning usually consists of heating the slag, reduction of oxides and settling of matte/metal droplets. Heating the slag decreases viscosity and accelerates reactions. Reduction of magnetite liberates inclusions and facilitates co-reduction of dissolved metal oxides. A significant amount of the matte and metal is present as very fine metallic inclusions, too small for settling. The coalescence of these matte or metal inclusions is required to remove them from the slag. The developed new concept of slag cleaning combines DC furnace technology with an extra magnetic field for vigorous slag stirring, enhancing mass transfer to the reductant surface, accelerating the rate of reduction, and destabilizing the emulsion of matte or metal inclusions. Intensive slag stirring increases the probability of collision of inclusions, will accelerate their growth and will therefore improve settling. The process is carried out in a patented DC channel furnace, where the liquid metal or matte layer acts as a cathode and the floating coke bed on the slag surface is the anode. In the first part of the furnace, a superimposed magnetic field induces a Lorentz's force causing the slag to start an intensive circular motion. The next furnace zone does not experience any stirring and is dedicated for quiet sedimentation of the inclusions. A mathematical model of gravitational coalescence combined with forced slag motion showed the possibilities of effective removal of copper matte inclusions. The results of laboratory pilot scale tests of continuous slag cleaning showed fast slag reduction and confirmed the improved matte removal from the slag. Conceptual analysis shows the potential use of the technology in various other non-ferrous industries, like for example nickel plants. It is also possible to use this technique batch wise.

Jan 1, 2007

By Brad Gunn

Our program has been dictated by the necessity of broadening our markets through converting potash chemicals to fertilizers more in demand than potassium chloride. To this end, we have undertaken studies on methods of preparing potassium sulphate or potassium magnesium sulphate by rather simple conversion. When mixtures of sodium and magnesium sulphates are reacted with potassium chloride, the ratio of sodium to magnesium is quite pertinent. A range of ratios has been selected and the conversions of potassium chloride to sulphate have been assessed by cyclic operations. Results from experimental procedures for producing potassium nitrate are also avail-able. The influence on recovery for systems including organic solvents is assessed for a variety of situations.

Jan 1, 1971

By M. Kosugi, Y. Kon, M. Kawata, J. V. Satur, K. Mitsuhashi, C. Tokoro, K. Horiuchi, R. Kawarabuki, B. Calabia

"Liberation of copper minerals is important in ensuring high flotation efficiency in copper sulfide flotation. The high pressure grinding roll (HPGR), microwave (MW), and electric disintegration (ED) are known to feature enhanced liberation over conventional comminution machines such as jaw crushers and ball mills by producing internal stresses on minerals or mineral grain boundaries through high compressive forces, thermal expansion of minerals, and pulsed high voltage discharges, respectively. In this study, each of these methods was applied before ball mill grinding to investigate its effect on enhancing the liberation of copper minerals in a low grade and fine-grained copper ore. The copper minerals observed in the tested ore sample are bornite, chalcocite, and chalcopyrite, and their grain sizes range from 10 to over 100 µm. Calcite, quartz, and feldsparare confirmed as gangue minerals. The liberation of the copper minerals by the different methods was analyzed using the mineral liberation analyzer (MLA) and compared. The result showed that the HPGR crushing was the most effective for enhancing copper mineral liberation. HPGR bench-scale test was then conducted on the copper ore and flotation was applied on a HPGR-treated sample to confirm the improvement in the flotation performance by applying HPGR.INTRODUCTIONIn order to recover copper minerals by flotation, copper ore is usually ground by ball milling to liberate the copper minerals from gangue minerals. In the case that the fine size copper minerals are targeted, grinding of the copper ore to a finer size is necessary to increase the copper recovery. However, finer size grinding by ball mill increases energy consumption significantly, which might deteriorate the economies of the mineral processing operation. HPGR, MW, and ED have been recently the focus of researchers as new techniques for enhancing the mineral liberation in mineral processing (Tavares, 2004; Kingman, 1998; Wang, 2010).HPGR crushing is considered to generate micro cracks along mineral boundary when rocks pass between two rolls by applying high compressive force. In the MW treatment, micro cracks are reported to be generated at crystal boundaries by differential thermal expansion of crystals attached to each other. In the ED treatment, micro cracks are known to be produced by plasma current flowing along mineral grain boundaries. These treatments are expected to increase mineral liberation (Fujita, 2001),improve flotation performance(Michaelis, 2005), and reduce ball mill work index(Kaya, 2010)."

Jan 1, 2017

By S. Power Warren

Introduction It is generally conceded by flotation men that the condition at the surface of a particle of mineral or gangue is the most important factor controlling its behaviour in a flotation cell. Much research work has been devoted to the study of the forces that are active at the surface of the particle and of the effect of the surrounding solution upon these forces. Study of the relationship between mineral or gangue particles and gas bubbles indicates that, in the main at least, flotation is a physical phenomenon. The important factor, that of mineral-gas-bubble attachment, is unquestionably physical; however, modifications may be effected by chemical means, whereby the nature either of the surface of the particle or of the surrounding solution may be changed. For example, the coating of lead sulphide that forms on lead-carbonate ore particles when sodium sulphide is added greatly aids the flotation of the carbonate particles. Without going into the question as to why, under certain surface conditions, mineral particles will attach themselves to gas bubbles whereas under other conditions they will remain unaffected, it may be stated that there are three general conditions in a flotation pulp which control the attachment of the particle and the gas bubble.

Jan 1, 1933

By E. Ghali

For engineering applications, magnesium is usually alloyed with one or more elements which include aluminium, manganese, rare earth metals, lithium, zinc, and zirconium. Under normal environmental conditions, the corrosion resistance of magnesium alloys is comparable or better than that of mild steel. The oxide film thickness on pure magnesium after exposure for only ?10 seconds at ambient temperature is 2.2 ± 0.3 nm. Exposure to humid air or to water leads to the formation of a thick hydrated amorphous film that has an oxidation rate less than 0.01 pm/ y. E-pH diagram and high temperature corrosion are discussed. The pH values between 8.5 and 11.5 correspond to a relatively protective oxide or hydroxide film that is more stable at higher pH. Structural applications of magnesium alloys are limited by creep strength rather than by oxidation. Active and active-passive behaviours of magnesium alloys are discussed. The pilling Bedworth Ratio values of oxide and hydroxide are 0.79 and 1.77 respectively and so the formation of Mg(OH)2 inside the oxide film could lead to the development of cracks. Microbiologically influenced corrosion and rational biodegradation of magnesium alloys are discussed because of their interest for medical care.

Jan 1, 2006

By Robert Macdonald, William Coombe, John F. Lewry

Gold occurrences have been known in the La Ronge Domain for many year . Mineable reserves have more recently been outlined and there is every prospect of a major gold camp being established in the domain within this decade. The La Ronge Domain lies in the Lower Proterozoic 'Trans-Hudson Orogen' and is part of a collage of Early Proterozoic crust comprising volcanoplutonic arcs, batholiths, associated volcaniclastics and volcanogenic sediments lying between the Superior Craton to the outheast and the reworked Archean basement/Aphebian cover terrain to the northwest. The domain has several lithostructural subdivisions, the most important of whjch , from a gold exploration point of view, is the Central Metavolcanic Belt. This belt is composed dominantly of a range of metavolcanic rocks and gabbroic to granitic intrusives, which geochemically resemble younger subduction-generated 'primitive' arcs developed on oceanic crust. U-Pb zircon geochronology indicates that the arc volcarusm and pre- to late-kjnematic plutonism occurred about 1890 Ma to 1850 Ma ago. The belt has an attained grade of upper greenschist to amphibolite facies and is relatively undeformed , though high strain zones occur locally. Most gold occurrences in the La Ronge Domain have been found in the Star-Waddy Lakes area of the Central Metavolcanic Belt, and in the Sulprude-MacKay Lakes area to the south which is interpreted as a tectonically dismembered part of the main belt. Both tratiformand vein-type gold occurrences are present in the domain; vein-type predominate and form nearly 90 per cent of the occurrences. The stratiform-type occurrences show a regional lithological a sociation with iron-rich sediments within proximal felsic volcanjc sequences. Some vein-type occurrences appear related to brittle fracturing associated with intrusive emplacement (the magmatic-hydrothermal "syn:' and "subvolcanic" veins) and faulting. However, most of the vein-type occurrences exhibit a spatial association with regionalscale ductile shear and other high strain zones, and were probably formed by metamorphichydrothermal processes.

Jan 1, 1986