Search Documents

By Robert A. Bosschart, Harold O. Seigel

"Most electromagnetic methods presently used in mining exploration are of the moving source type; i.e., the primary field source is moved simultaneously and in a fixed configuration with the receiver. Of the fixed-source methods, which employ a stationary primary field and a moving receiver, the Turam method is the most effective and has marked advantages over alternative electromagnetic methods. The results are little affected by topographic relief, and a high degree of resolution can be obtained because of the constant relation between source field and investigation area. Another inherent advantage of the Turam configuration is that it provides more favourable dimensional relations. Thus, the primary field attenuates at a much lower rate than in moving-source configurations and, secondly, the method is size sensitive; i.e., conductor size affects the strength of the response, which is not the case with moving-source methods. These factors result in a considerably better potential depth penetration."

Jan 1, 1966

By Forrest A. Kerr

Introduction During recent years the work of the Geological Survey in northwestern British Columbia has been in the nature of reconnaissance and exploratory mapping, largely for the purpose of gaining knowledge of the potential mineral-producing zones known to occur along the eastern side of the Coast range, and also to gather such data as might facilitate their exploitation. Commencing with fairly detailed mapping in the more accessible parts, the work has been continued and expanded until now an understanding has been gained of the more general features of a continuous section along the range for a distance of about two hundred miles. Geographically, northern British Columbia is more or less isolated. It is cut off from the central part of the Province by a rugged and mountainous country which, except for the telegraph line and a rarely travelled trail along it, is not penetrated by any developed routes or lines of communication. To the west, it is cut off from the Pacific by the Coast range, an extremely rugged area sixty to eighty miles in width which, except along the few navigable rivers cutting across it, cannot be readily traversed. Politically, it is further isolated in this direction by the narrow strip of south-eastern Alaska which borders the coast and extends inland to the axis of the range.

Jan 1, 1931

By E. S. Allen, P. R. Kruesi, J. L. Lake

An electrochemical process is described for converting concentrates of base-metal sulphides to the corresponding pure metals and elemental sulphur. The application of the process to chalcopyrite is discussed. The process is also of potential interest in processing copper-nickel sulphides, and laboratory data concerning this potential are presented. The process creates neither air nor water pollution.

Jan 1, 1973

By Diego L. Romero, Joy P. Romero

"IntroductionThe purpose of this paper is to explain the theory and demonstrate the industrial applications of electrostatic separation. Wabush Mines' use of this type of processing for the concentration of iron ore is unique in the industry. Other minerals are concentrated electrostatically but the process is not widely used.Typical minerals separated by electrostatic separation techniques are:Non-ConductorsAnhydriteApatiteBariteBastnasiteBerylCalciteChrysotileCorundumDiamondEpidoteFeldsparsFluoriteGarnetGypsumHornblendeKyaniteAcmiteAugiteBrookiteCassiteriteChalcopyriteChromiteColumbiteCopperDaviditeEuxeniteFerberiteFrankliniteGalenaGoldGraphiteHematiteMica (Biotite)Mica (Muscovite)MonaziteOlivinePerovskiteQuartzScheeliteSideriteSillimaniteSpheneStauroliteSulphurTopazTourmalineXenotimeZirconConductorsIlmeniteIlmenite-( High Iron)IlvaiteKoppiteMagnetiteMarmatiteMolybdenitePyriteRutileSamarskiteSphaleriteTantaliteWolframiteWulfeniteThe limitations of this process are:1. There must be a difference in conductivity between the minerals being separated.2. The size range must not be very wide.3. The specific gravity of minerals being separated should be similar or the minerals to be pinned should be lighter. 4. The feed must be dry.5. The particle shape should be more or less uniform. 6. The feed must not be high in true middling particles."

Jan 1, 1989

By Christopher Boys

"Abstract -Many water inflows in Saskatchewan potash mines are linked to salt anomalies. Potash ore and three anomalies in the PCS Cory potash mine in the Patience Lake Member of the Prairie Evaporite Formation were studied to understand the processes involved in their formation. Another goal was to find geological indicators of the proximity of anomalies. A geological model that relates the potash to the salt anomalies has been developed.Up to five post-burial facies may be recognized . These range from carbonate-mud collapse breccias to bedded sylvinite, and probably result from post-burial leaching. ln this model, the same fluids that caused widespread recrystallization and possibly enrichment of the potash salts, started by dis­ solving huge cavities in the evaporites . The effects of the leaching were highly variable, indicated by selectively preserved delicate laminae and chevron textures, to deformed and totally dissolved salt beds . ln at least two major events, Late Devonian and Cretaceous, collapse structures may have acted as conduits for overlying formation waters to cause pervasive leaching and recrystallization of the Prairie Evaporite Formation .Geological indicators of the proximity of an anomaly may include: a change in Insoluble seam color from greenish-gray to mottled brown and greenish-gray, unusual local increases in ore grade, large patches (e.g., >200 cm2) of sylvite-poor potash crosscutting units near the top of the ore zone, and drops in topography >10 m of the marker seams. Anhydrite was more common in an anomaly than in ore. The local abundance of anhydrite in ore may indicate the proximity of some salt anomalies.Once an anomaly has been encountered, indicators of a major collapse feature may include: stretched clay seams, folded beds, small collapse features (1 m to 20 m), numerous washouts, or split clay seams with injected salt. Any number, or none, of these indicators may be found close to a major collapse feature."

Jan 1, 1993

By P. E. Cavanagh

FOR THE PAST seven years Mr. W. Simpson, Chief Mechanical Inspector for the Nova Scotia Department of Mines, has carried out exhaustive field trials of non-destructive inspection equipment in the coal mines of that Province. This work has demonstrated the usefulness of a number of types of non-destructive inspection when used for periodic inspection of hoisting and haulage equipment in the coal mines of Nova Scotia. As a result, the Dominion Coal Company has instituted a programme of regular preventive maintenance inspection ?by a special staff of qualified and trained men. The purpose of this present paper is to describe how non-destructive testing techniques are used on ropes, axles, couplings, and other hoisting and haulage equipment, how these methods are being used in other industries, and the expected benefits from intelligent and properly organized use of these techniques in the coal mining industry.

Jan 1, 1956

By R. L. Brown

The burning sulphide ores in the Sullivan Mine generate sulphur dioxide gases. This paper is concerned with a description of the environmental impact of SO2 on air quality in the mine and on the surface in the vicinity of the mine. As a result of surface caving, SO2 has been able to vent to surface and winds have carried it into one residential area of Kimberley. Monitoring practices are described.

Jan 1, 1977

By James D. Bittner

Separation Technologies, LLC (ST) has developed a processing system based on triboelectric charging and electrostatic separation that provides the mineral processing industry a means to beneficiate fine materials with an entirely dry technology. The environmentally friendly process can eliminate wet processing and required drying of the final material. The process requires little if any pre-treatment of the material other than grinding and operates at high capacity ? up to 40 tonnes per hour by a compact machine. Energy consumption is low, approximately 1 kWh/tonne of material processed. Since the only potential emission of the process is dust, permitting is typically relatively easy. In contrast to the other available electrostatic separation processes that are typically limited to particles greater than 75 µm in size, the ST belt separator is ideally suited for separation of very fine (<1 µm) to moderately coarse (300 µm) materials with very high throughputs. The triboelectric particle charging is effective for a wide range of materials and only requires particle ? particle contact. The small gap, high electric field, counter current flow, vigorous particle-particle agitation and self-cleaning action of the belt on the electrodes are the critical features of the ST separator. The high efficiency multi-stage separation through charging / recharging and internal recycle results in far superior separations and is effective on fine materials that cannot be separated at all by the conventional electrostatic techniques. Since 1995, this triboelectric process has been extensively used for the beneficiation of coal fly ash with eighteen separators in place and over 130 machine-years of operation at locations in North America and Europe. ST has also installed separators for the beneficiation of industrial minerals in North America and Europe. The technology has been successfully applied to the beneficiation of a variety of minerals including calcium carbonates, talc, barite, and potash.

Aug 1, 2013

By R. L. Veenstra

This paper explores the connection between the stresses observed and the failure mechanisms present in the modelled cemented paste backfill. In order to look at this connection, the authors have used a previously developed model to conduct a sensitivity analysis of the model?s strength and permeability input parameters. The results from the sensitivity analysis were then compared to determine what causes modelled stresses and failure mechanisms to vary. Increased insight into the behaviour of the modelled paste will help clarify how paste behaves in the field.

Aug 1, 2013

By Lionel C. Piuze

Introduction and Early History The British Canadian Mine is one of four operating properties of Asbestos Corporation, Limited, and is located in the town of Black Lake, Que., five miles southwest of Thetford Mines. In the early days of as1bestos mining, this .property was owned by a few small companies who later became part of the Asbestos Corporation. First .to commence mining operations on the property was the Coleraine Mining Company who, in 1885, began selling part of their large holdings in the area to various asbestos mining interests. Of these, the earliest active companies were Manhattan United Asbestos, the Glasgow and Montreal Asbestos Company, and the Anglo-Canadian, the last named later becoming the Standard and Dominion Asbestos Companies. Extraction of fibre was limited to what is now known as crude asbestos and the methods were primitive. Drilling was done .by hand and the ore was lifted by derricks operated by band winches. These were later replaced by horse power, but it was not until 1887 that the first steam-operated boom derricks were introduced, at the Anglo-Canadian mine. The ore was hand cobbled and the asbestos roughly classified and bagged. The waste rock, which by today&apos;s standards contained a considerable percentage of marketable fibre, was dumped near the pit. The first attempt to separate the asbestos from the host rock by mechanical means was made in 1888 by the G1asgow and Montreal Asbestos Company, then known as the Scottish-Canadian Asbestos Company, whose mill, erected in that year, was the world&apos;s first asbestos mill. Though the equipment was crude, the principles employed were the same as those used today with much larger units. The next steps were the use of rock drills, the adoption of steam rail transportation for moving mill rock, and conversion to the more flexible cable-derrick hoisting.

Jan 1, 1950

The effect of superficial gas rate distribution (Jg profile) on down-the-bank metallurgical response was tested in the rougher-scavenger bank (eight 10-m3 tank cells, 4 roughers and 4 scavengers) at Highland Valley Copper Mine&apos;s Cu/Mo separation circuit. Three Jg profiles were tested: (a) as found (i.e., typical practice), (b) increasing decreasing (i.e., increasing from cell 1 to 4 and decreasing from cell 5 to 8), and (c) decreasing-increasing (i.e., decreasing from cell 1 to 4 and increasing from cell 5 to 8). The Jg profile approach proved to be of considerable value. Profile (b) gave the best metallurgical results, i.e., the highest down-the-bank grade/recovery (increase in grade at constant recovery was approx. 3-4% compared to the as found case) and the most efficient Cu/Mo separation (cumulative Cu recovery was reduced by almost half - approx. from 20% to 12%, at 99% Mo recovery). The success of the evaluation prompted the implementation of profile (b). Detailed gas dispersion characterization tests (Jg and Db (bubble size)) showed significant discrepancies between the Jg measured directly (using the McGill University sensor) and the Jg calculated from field instrument readings (volumetric gas flowmeter) and machine dimensions (cell cross-sectional area). Tests were designed to reveal the source of disagreement. It was observed that a significant number of bubbles were not able to float (i.e., they were entrained with the tailings), the evidence appearing to be a significant number of very small bubbles (approx. 200-300 µm) which did not have sufficient buoyancy to rise. Consequently, rather than relying on the field instrument, the evaluation depended on the McGill University Jg sensor, which collects bubbles in a tube near the pulp-froth interface, thus providing significance to the data as the measurements were obtained from bubbles that almost certainly floated.

Jan 1, 2007

By A. Cummings

This paper reports two aspects of reactivity of complex Ni-Cu sulphide ores: variations that result from stockpiling of a nickel-copper sulphide ore in the Sudbury area and its consequences on flotation behaviour, especially in terms of metal losses to scavenger tails. In relation to the first aspect, self-heating characteristics of the stockpile were carried out by monitoring the internal temperatures of the stockpile. Six heat sensors were installed with respect to external conditions in local weather during a 7-month period. Stockpile temperatures were mainly influenced by ambient temperature with some retardation effects. The maximum temperature recorded in the stockpile was 44 °C. Samples taken at the beginning and at the end of stockpiling were tested to assess variations in behaviour of the rougher-scavenger flotation. Relative to the fresh ore, nickel and copper losses in flotation of the stockpile fines were 5.0 and 3.6 %, respectively. The fresh ore yields concentrates with higher nickel grades due to differential flotation behaviour of pentlandite and pyrrhotite relative to the stockpile fines, which exhibit a truly bulk flotation behaviour at least during the first 3 stages.

Aug 1, 2013

By Ralf M. Kleine

THE property of Consolidated 1 Discovery Yellowknife Mines Limited, (Figure I) is situated in the Northwest Territories, approximately 50 air miles north of the town of Yellowknife. The mine is reached by a shaft which extends from surface to a depth of 4,000 feet, with working levels established at 1 50-foot intervals. Stopping operations are carried on throughout a vertical range of 2,000 feet, with both shrinkage and cut and fill methods being used, depending on the ground conditions. Production started in 1950 and milling is done in a 1 65-ton per day cyanide plant. During ten months of the year, the property is serviced entirely by air, utilizing charter aircraft from Yellowknife. A 4,000-foot runway near the mine was constructed from mill tailings. This strip is adequate to receive Bristol freighter planes carrying heavy loads. Other servicing is done by Otter aircraft, equipped with skis or wheels for winter and with pontoons for summer operations.

Jan 1, 1962

This paper discusses three case studies conducted at Highland Valley Copper mine (HVC) that illustrate operational improvements and insights which resulted from using the McGill University gas dispersion sensors. In the first study, the superficial gas velocity (Jg) sensor was used to implement a gas profiling control strategy for the rougher, scavenger and first cleaner cells in the Cu/Mo separation circuit. The data showed a 40% reduction of down-the-bank Cu recovery at constant Mo recovery which resulted from operating the cells at the target profiles. In the second study, the bubble size analyzer was used to better understand two mechanisms of bubble formation in the two flotation columns that make up the final Mo cleaning stage: the conventional rubber-sleeve sparger and the Microcel(TM) system. The data showed a considerable reduction of bubble size in the Microcel column which resulted in a significant increase in concentrate quality (1-2% Mo absolute) and a dramatic (4-5 fold) increase in concentrate production rate compared to the typical operation. The estimated economic benefit resulting from the improved column flotation operation was an overall 4% increase in Mo circuit recovery. In the third study, real-time measurements obtained from the gas holdup and bulk density sensors were used to infer the pulp density (% solids) in a rougher cell of the bulk flotation circuit. Validation tests demonstrated that this approach provides reliable pulp density measurements. Although promising, more work is required before implementing this approach at HVC.

Jan 1, 2009

By W W. Moorhouse

A survey of recent literature indicates that sulphides occur in the volcanic rocks of the Archean, or in sedimentary rocks intercalated with the volcanic rocks. The thick sedimentary sections are generally poor in sulphides. Thus, the widespread pyrite and pyrrhotite mineralization in the Archean may be largely of volcanic origin. Introduction I N this paper, commercial base-metal deposits will not be considered, as they are dealt with in other papers of the Symposium. Instead, attention will be focused on those sulphides, often associated with graphitic argillites or tuffs, which have appeared in such embarrassing abundance in electromagnetic surveys of Archean areas. The data on which the paper is based are drawn from recent reports of the Ontario Department of Mines, the Quebec Department of Natural Resources and the Geological Survey of Canada. The information available from these sources is unfortunately limited, because sulphides commonly occur in sheared rocks, such as black argillites and tuffs, which rarely form conspicuous outcrops, and may not be exposed at all. Thus, in the absence of geophysical information, even detailed mapping may fail to reveal the presence of sulphide-rich rocks.

Jan 1, 1965

By Brian Hart, Stamen S. Dimov

"The naturally occurring carbonaceous material (CM) in gold bearing ores often exhibits strong-preg-robbing properties. It can adversely affect the process of gold recovery during the cyanidation due to its ability to adsorb, or preg-rob gold from the cyanide leach solution.Treatments of carbonaceous ores with chemical surfactants as blinding agents to limit preg-robbing have shown promising results but at the same time have demonstrated that, if not properly used, could have a strong detrimental effect on the gold recovery process. High dosages of surfactants used as passivating agents for carbonaceous matter could lead to unwanted partial passivation of the activated carbon added during the CIL process and severely impact the gold recovery. Optimal dosage for various surfactants would strongly depend on the ore mineralogy and the parameters of the pulp (temperature, pH, surface area and maturity of the carbonaceous material, etc).This paper describes an experimental study on the effectiveness of various commercially available blinding agents used to minimize the preg-robbing capacity of naturally occurring carbonaceous matter. The scope of the study was to: i) establish the optimum addition of blanking agent (surfactant) to minimize the preg-robbing capacity of the CM in the ore, and ii) establish maximum threshold amounts of blanking agents to be used before it negatively impacts the preg-robbing capacity of the activated carbon used in the CIL process. The study procedure involves standardized doping tests to evaluate the maximum preg-robbing capacity of treated CM, coupled with surface analysis with ToF-SIMS to monitor the presence and the degree of loading of these chemical surfactants on both the naturally occurring CM and the added activated carbon.INTRODUCTIONNaturally occurring carbonaceous material (CM) in gold bearing ores often exhibits strong-preg-robbing properties. Thus, it can adversely affect the process of gold recovery during cyanidation due to its ability to adsorb, or preg-rob gold from the cyanide leach solution. The preg-robbing properties of this naturally occurring carbonaceous matter can vary widely between ores, and within a single ore body (Dunne et al.,2013;Helm et al.,2009;Miller et al.,2005). The degree of preg-robbing related to the CM within an ore is defined by several parameters: total organic carbon (TOC) content, surface area, maturity (i.e., crystallinity) of the CM and the presence of various functional groups on the surface of the CM. Preg-robbing gold ores continue to be a significant challenge because of the lack of a single or universal solutions."

Jan 1, 2016

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 The Staff

Introduction It is the purpose of this paper to discuss a number of the metallurgical improvements in the technology of copper-nickel ore treatment which have been introduced during recent years in the plants of ?the International Nickel Company of Canada, Limited. In common with other ore treatment processes, the procedure for extracting nickel and copper is changing almost continuous! y. These changes are necessitated by reason of changes in ore grades and characteristics, rising material and labour charges, and the constant drive to maximize metal recovery and to minimize production costs. It is not possible to present a comprehensive list of all the changes made, and only a selected number of the improvements in the milling, smelting, and refining operations are covered. It should be clearly understood that some phases of the procedures described have been pioneered by others in kindred fields and due acknowledgment is given to their foresight and efforts. Articles have been published over the years describing the operations of the International Nickel Company plants and the reader is referred to the Engineering and Mining Journal, Vol. 130, No. 9, November 10th, 1930, and to the Canadian Mining Journal, Vol. 58, No. 11, November, 1937, and Vol. 67, No. 5, May, 1946. Other references are the Transactions of this Institute, 1932, 1938, and 1946; Metals Technology, American Institute of Mining and Metallurgical Engineers, February, 1938, and Canadian Chemistry and Process Industries, April, 1940.

Jan 1, 1948

By Lewis Finch

Oil and .gas reservoirs exist under pressure within the pore spaces of rock structures or traps. Wells are drilled to produce these reservoirs. Under primary operation, the natural energy of expanding fluids in and adjacent to the reservoir forces or drives oil and gas to the wells. There are three basic sources of energy: dissolved gas, water, and gas cap. Typical recovery by primary methods is only 10 to 25 per cent of the oil in place for the dissolved gas drive but is generally higher for the others. Secondary recovery involves the injection of water or gas to supplement natural energy, thereby increasing recovery over that obtainable by primary operation alone. In many cases ultimate recovery with secondary methods is 1.2 to 2.0 times the expected primary recovery. The type programme adaptable in a field depends on its &apos;primary performance and on certain reservoir characteristics. In the United States, application of secondary recovery methods is becoming increasingly important. About 22 per cent of United States oil production now comes from fields in which injection projects are operating. In 1953, nearly 1.4 million barrels of oil daily came from such fields, more than double the amount in the early 40&apos;s. Ultimate primary recovery from known pools is estimated at roughly 73 billion barrels. Secondary recovery projects already in operation will increase this to almost 80 billion, an increase of almost 10 per cent. Unitized secondary recovery projects have been very successful. From unitized projects alone, industry reserves of oil in the United States have been increased by 3 1/2 billion barrels. In Canada, secondary recovery has not been so wide spread mainly because D-3 reef reservoirs which have held the major reserves are under water drive. However, appreciable amounts of water are being injected in the Redwater D-3, Leduc D-2 and Joarcum Viking reservoirs, and gas in the Golden Spike D-3. In both countries, possible achievements in increased recovery through secondary recovery methods now in use and by new ones which may be developed through research and field trial are a challenge to the scientist and the industry.

Jan 1, 1956

By J. C. Hawkins

Determining moisture content and rate of flow of a solid product make measurement and control of dryers unusually difficult. This paper de-scribes a method of accomplishing this with readily made air-temperature measurements. The system can cope with changes in feed moisture and feed rate. It does not measure solids temperature. The system's application to several typical rotary dryers is described, and control schemes using feedforward techniques are explained.

Jan 1, 1971