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By H. Miki, S. Wheatley

The addition of precipitated silica greatly enhances chalcopyrite leaching in the presence of sodium chloride at moderate temperatures (65-90°C) in acid media with ferric ions as the oxidant. The beneficial effect increases with the increase in chloride concentration and temperature. The addition of sodium silicate and silica sand has no significant influence. The analysis of solubility data in acid/salt solutions indicates that the solubility of silica as Si(OH)4 as the dissolved species is controlled by the activity of water, as expected from the hydration theory. Kinetic analysis shows the trends that copper dissolution from chalcopyrite in the presence of precipitated silica with sodium chloride follows a shrinking sphere model indicating a chemically controlled surface reaction. The effect of temperature on copper dissolution in the presence of both precipitated silica and sodium chloride was also larger compared to the results in sodium chloride alone. The SEM analysis shows that chloride and silica facilitates the precipitation of sulfur on the surface of the silica particles rather than the chalcopyrite particles which avoids the blockage of the mineral surface and thus improves the leaching kinetics.

Jan 1, 2014

By M. A. Halim, V. I. Lakshmanan

Recycling is one of the key elements for sustainable process development for the recovery of value-added products and reducing environmental impact. Process Research ORTECH Inc. has developed several innovative and sustainable technologies, which minimizes the use of water, and chemicals for the recovery of gold, vanadium and gallium from secondary sources by maximizing the recycling of reagents, and reuse of water from process effluents.

Jan 1, 2015

By K. B. Chaudhurl

The thermodynamics of the reactions taking place are examined with the aid of equilibrium diagrams for the Pb-O-S system. Based on investigations of chemical, mineralogical and differential-thermo analyses of intermediate products of different desulphuration degrees, an attempt is made to explain the mechanisms of the reactions in the smelting shaft of the KIVCET furnace. The differences between this and other direct lead smelting processes are demonstrated by these thermodynamic and kinetic considerations. Proceeding from these results, the practicability of direct lead smelting processes is discussed with reference to the composition of the primary feed materials to be processed. This comparison also considers the behaviour of minor metals, the products obtained and their characteristics in respect to further treatment. For assessing the operating costs, the over-all energy consumption is considered taking into account various price relations between electric energy and fuels/reductants. Based on the peculiarities of the various processes, an attempt is made to compare the necessary means of meeting the pollution control requirements. The paper concludes with reference to the criteria and problems involved in comparable evaluations.

Jan 1, 1978

By G. W. Norval, V. G. Papangelakis, G. A. Moldoveanu

Smelting has been the primary method of treatment for refractory copper sulfide concentrates such as enargite (Cu3AsS4), but the pyrometallurgical processing generates elevated levels of volatile arsenic. The present research investigates a novel hydrometallurgical process of oxidative dissolution of enargite at ambient conditions in the presence of chlorine dioxide (ClO2), a very powerful oxidant generated in solution by the reaction between a strong acid (HCl or H2SO4) and sodium chlorite (NaClO2). The effects of initial oxidant concentration, particle size, agitation speed and temperature on dissolution kinetics and copper extraction were investigated. It was found that a stoichiometric ratio of ClO2:Cu3AsS4 = 9:1 were needed to completely and congruently dissolve the mineral with fast kinetics (<15 minutes) under ambient temperature. The dissolution extent (metal extraction) increases with increasing ClO2 concentration and decreasing particle size of solids, but is not influenced by temperature or agitation speed.

Jan 1, 2014

By Daniel E. Walsh, P. D. Rao

"A four-inch compound water cyclone (CWC) was tested to evaluate its gold recovery characteristics when processing -4.8 mm run-or-pit, placer material. Neutron activated placer gold particles (840 to 37 microns) were used as radiotracers (/98Au) in a closed circuit ewe test loop to determine concentrator recovery; a procedure believed unique to this study. The effect on gold recovery of gold size and shape, feed pulp density, feed pressure, vortex finder clearance (VFC), ewe cone type, top-size of the feed solids, presence or absence of heavy minerals in the feed, and the quantity of-37 micron slimes in the feed was investigated in over 300 tests.CWC concentration ratio and the top-size of the underflow solids were both affected by cone type, VFC, and feed pressure. Gold recovery was significantly affected by gold size, gold shape, and concentration ratio. These effects are complex, because significant size-concentration ratio and size-shape interactions exist. Radiotracer techniques showed gold particles had a residence time within the ewe of approximately one second. This study suggests ewe gold recovery is a concentration. This work suggests ewe gold recovery is a function of particle size and shape, and the flow rate through the cyclone. CWC cone ""bed density"" is considered important only as a thin, protective layer, which shields coarser gold particles from the entraining currents and facilitates their movement through the CWC.IntroductionCompound water cyclones (CWC), or automedium cyclones, are enhanced gravity concentrators for the beneficiation for slurries of sand, coal, and ground ore (Fig. 1). They are called compound water cyclones because of the compound slopes of their basal cones (Fig. 2) and are operated to suppress classification phenomena in favour of gravity concentration effects. The compound water cyclone is not a new wet concentrator. It was developed in the late 1950s by Dr. Jan Visman through research sponsored by Canada&apos;s Department of Energy, Mines, and Resources. Since that time, it has become a common unit in coal washeries for cleaning fine coal. CWCs and other versions of concentrating cyclones have also shown promise for heavy minerals and precious metals recovery."

Jan 1, 1988

By T. G. Joseph, M. Welz

ABSTRACT: Joseph (2002) introduced passive seismic monitoring to measure mining equipment performance. This paper evaluates the potential of passive seismic monitoring to correlate mining equipment operation with oil sands surface response, with a mining hauler as the seismic source. When applied to moving haulers, this action–reaction approach is complex. Vibrations from on-board equipment, such as pumps and tires, dirty the signal with noise. To facilitate any correlation, the signal must be cleaned up. Existing geophysical analytical techniques were manipulated to evaluate the noise problem and to filter sufficiently to permit an evaluation of whether a mining equipment action–ground response relationshipis in fact discernable.

Jan 1, 2011

By Richard J. Wardle, Ambrose F. Howse

The industrial minerals industry in Newfoundland and Labrador is a significant contributor to the provincial economy. The variety ofcommodities produced reflects the diverse geological environment from which they come. A highlight of the past decade has been the continuing development of dimension stone quarries, with producers now active in anorthosite, gabbro, granite and sandstone. Other dimension stone prospects have been identified and are in various stages of assessment and development. Western Newfoundland hosts a large resource of limestone, dolomite and marble. It provides raw material for industries that produce Portland cement, agricultural limestone and aggregate, as well as chemical-grade limestone and dolomite products. In western Labrador, dolomitic marble is quarried for use in the production of self-fluxing iron ore pellets. The recent opening of a new gypsum quarry at Fischells Brook signalled the beginning of a new era in the commercial production ofgypsum, a commodity which the province has produced since the 1950s. Hopefully it will emulate the nearby Flat Bay Quarry (now closed) which was a long-time exporter to markets along the U.S. eastern seaboard, in addition to supplying local demands. Oil production and continuing exploration in the Newfoundland offshore has renewed interest in local barite deposits for potential use in drilling fluids. Already there has been some production from the Collier Point deposit, and at Buchans, an existing plant is being refurbished to recover barite from a large tailings pond. Emerging new industries include the development of an antimony mine in central Newfoundland, the development of silica deposits near Labrador City for silicon metal production, and reactivation of the St. Lawrence fluorspar mine. The province has many deposits with development potential such as rare metals at Strange Lake, white marble at Roddickton and salt deposits near St. George's Bay region.

Jan 1, 2001

By C. R. Julian

MECHANIZATION During the last fifteen years, numerous attempts have been made to mechanize the operations of loading ore and placing till. It is to be regretted that, to date, little progress has been made in this direction. The comparative efficiency of manual labour in Spain is the factor largely responsible for the failure to cheapen costs by mechanization. The necessity for careful classification of the ore and the need for keeping all openings small also makes the problem one of difficulty. It may be of interest to describe the various attempts at mechanization that have so far been made. CONVEYORS: (1) When stoping by layout III in San Dionisio, a trial was made of transporting the filling by jigging conveyors. This method proved un-economical, as the wall building and spreading of the till could not keep pace with the delivery, with the result that the machinery was idle a great part of the shift. (2) The transport of ore from the working places to the ore-passes by jigging conveyors and belts was also tried. Although more successful than in the case of the fill, the method could not compete with that of hand tramming, principally due to the high cost of (a) maintenance caused by the abrasiveness of pyrites, and (b) labour constantly employed on re-aligning the conveyors owing to the constant settlement of the floor. In a few cases, where a sill floor was being blocked out in virgin ground, the method showed a saving. SCRAPERS: Frequent attempts at loading by scrapers have been made, but again the only success obtained has been in the blocking-out of sill floors. The principal obstacle to the successful application of scraping, other than on the sill floor, has been that the openings, which have to be small, call for a light scraper outfit, whereas, in practice, a heavy scraper and at least a 25 h.p. winch are necessary for handling satisfactorily the ore, which is heavy and which breaks somewhat blockily.

Jan 1, 1940

By S. L. Gertsman

Canadian steel foundry practice has made marked progress during the past decade. Equipment suppliers, development engineers, and foundry personnel have focussed their attention on every phase of the foundry operation, with a resulting lower demand on manpower and materials. Also, more rigid specification requirements as to dimensional tolerances and quality have necessitated improvement and increased control at every stage from the pattern shop to the cleaning room. The growing trend toward mechanization is clearly evident. Equipment such as sand mixers, sand reclamation systems, material handling devices, moulding machines, core blowers, etc., is being increasingly employed by the steel foundryman. This equipment not only increases production but also tends to lessen the human variable so prevalent and disconcerting in the early days of steel founding. The result has been an improved and more reliable steel casting, which is gradually obtaining wider acceptance by design engineers. The purpose of this paper is to discuss briefly some of the practices being used, and also the direction of development that is being pursued by Canadian steel foundrymen.

Jan 1, 1948

By R. E. Gilmore

PREAMBLE THIS PAPER comprises material presented in two separate &apos;Papers at the British Commonwealth Scientific Specialist Conference on Fuel Research held in London, England, in July, 1950. These papers are now available for publication in Canada, since only essential parts of the conference discussions, in addition to the resolutions resulting therefrom, will be published in the official Proceedings of the Conference. Inasmuch as the information presented concerns Canadian organizations and training facilities for fuel research, it should be of general interest to Canadian scientists, and especially to the Coal Division of the Canadian Institute of Mining and Metallurgy. Part I, the alternate title of which is Facilities in Canada for Fuel Research and for Exchange of Information and Staff, does not include research on peat, oil shale, petroleum oils in general, and natural gas, and omits studies of the geology, constitution, and production of coal. Special reference is, however, made to research on the heavy crude oils and bitumen of the Western Prairie Provinces, and particularly to their production and treatment to produce crudes for oil refinery processing.

Jan 1, 1951

By Cummings. J. B., R. Haworth

"THE OPERATION of the Potash Company of America, Ltd., at its plant near Saskatoon, Saskatchewan, is the result of many years of exploratory and development work, culminating in the construction of a shaft, milling, concentrating and other facilities necessary to the production of potash in a marketable form.The possibility that potash existed in •commercial quantities in Saskatchewan was first indicated in 1943, although it was not until mid-1946, when Bata Petroleums penetrated a potash bed at its Verbata No. 2 well near Unity that substantial in-ter.est was developed in the possible exploitation of this important mineral product.The Potash Company of America, which is the largest producer of pot-ash in the Carlsbad, New Mexico area, a district that has been sup-plying about 90 per cent of the North American potash demand, be-came interested in the Saskatchewan deposits •at an early stage. Its engineers made an intensive study of the western Saskatchewan area in 1947 and continued their review of operating problems throughout the next three years.""Potash"" is the commonly used general term applied to the minerals of potassium, of which there are several. The most common mineral forms in which it is produced are potassium chloride and potassium sulphate. The potash content of potassium compounds is ordinarily ex-pressed in terms of potassium oxide (K20) equivalent."

Jan 1, 1960

By M. E. Holter

"Limestone-bearing strata are exposed in seven areas of Alberta, each situated adjacent to rail and road facilities. Six of these centers are located along the eastern edge of the Foothills and Front Ranges of the Rocky Mountains in western Alberta. The other is in northeastern Alberta, along the eastern margin of the Alberta Basin. High-grade limestones are present in Middle Cambrian, Upper Devonian and Mississippian strata. Middle Cambrian (Eldon Formation) limestones have been exploited only in the Exshaw area west of Calgary, where they formerly were used for lime production. Limestone beds of the Upper Devonian Palliser Formation are exploited at Exshaw and at Cadomin in west-central Alberta for the manufacture of cement. Reserves of high-grade limestone also are available in the Palliser Formation near Crowsnest Lake in southwestern Alberta and near BrUle, west of Edmonton. Upper Devonian limestones of the Waterways Formation are widespread in the Fort McMurray area of northeastern Alberta, but available data indicate they are of inferior quality to the limestone deposits of the Rocky Mountains regions. The Mississippian Livingstone Formation contains large reserves of high-grade limestone at several localities in the Rocky Mountains and Foothills. Commercial development of the unit is now underway at Crowsnest Lake and at Exshaw for lime production, and future exploitation of these beds is feasible at Blairmore and Nordegg."

Jan 1, 1973

By S. A. Bradford

The twenty years before World War I was the Golden Age of copper smelting in British Columbia. In this short time, the smelters developed from small, primitive units to large, efficient operations. The first copper claims had been staked on Howe Sound and Knight Inlet in 1864, and there was extensive copper mining in the interior by the mid-1880s, but before 1895, all ore was shipped out of the country for smelting, converting and refining. The first interest in smelter construction was undoubtedly inspired by a Provincial bonus and Dominion land grants offered to smelter builders. The early smelters made use of small blast furnaces which were designed to smelt any kind of ore, but usually far too little ore was available. The first smelter seems to have been the McRae furnace on the Spillimacheen River (1883), followed by Vancouver (1889), Revelstoke (1891), and Golden (1891) (1). They each smelted a few tons of galena and then quickly closed down permanently for lack of ore. Only smelters that actually produced some copper matte are described in the following sections.

Jan 1, 1999

By S. F. Featherby

"This paper traces briefly the historical development of coal handling systems to meet the needs of a rapidly developing thermal power generation technology. The wide range of operating requirements is demonstrated by comparing and contrasting the Wabamun GS of Calgary Power Ltd. and a typical modern Ontario-Hydro thermal plant. The problems of safe storage of large tonnages of coal in stockpiles are discussed, together with recommendations for stockpile management. The development of coal bunkers and their management is discussed in detail, together with future trends in the industry."

Jan 1, 1966

By Richard P. Curtin, John M. Goris, Lewis A. Martin

Cable bolt supports are being recognized as an effective ground control system in under-ground coal mines in North America, and their use has increased considerably during the past few years. The U.S. Bureau of Mines personnel are conducting both laboratory and field tests to evaluate the performance of these supports under a variety of conditions and to establish realistic design guidelines. This paper describes efforts to evaluate the capability of cable bolts to resist the high shear forces often present in longwall operations. Shear tests were conducted on pairs of 0.025 m3 (0.88 cu. ft) concrete blocks having joint surfaces ranging from rough to smooth. Tests were conducted on blocks both with and without reinforcement with 15.2 mm (0.6 in.) diameter steel cables. During each shear test, the loads and displacements along the normal and shear axes, as well as loads on the cable, were monitored. Cableloads were determined using strain gauges attached to the outside surfaces of the barrel-and-wedge anchors used for pretensioning the cables. Test results show that a cable bolt placed across a joint more than doubled shear resistance of shear blocks having both smooth and rough joints.

Jan 1, 1996

By Patrick Mclaren, Peter B. Hale

Canada, with one of the largest continental shelf areas in the world, has done little to evaluate its offshore unconsolidated mineral resources which include heavy minerals (gold, chromite, rutile etc.) and industrial minerals (silica sand and aggregates). During glaciation much of the continental shelf was covered with an ice sheet and later subaerially exposed with the result that glacial, glaciomarine and fluvial processes deposited sediments that may contain heavy minerals derived from onland locations. With rising sea-levels, beach and nearshore processes may have served to concentrate heavy minerals by winnowing and removing the lighter mineral components. These potentially valuable resources can be found with suitable exploration techniques such as seismic profiling and bottom sampling. Gold deposits are known to exist off the coast of Nova Scotia, and on the basis of form er beach mining, gold deposits probably occur off Vancouver Island and the Queen Charlotte Islands. Large deposits of silica sand occur near the Madeleine Islands and it appears likely that supplies of marine aggregates are present close to urban markets or sites of future mega-projects such as oil field developments. This paper, which is based upon a review of literature and consultation with members of the Department of Energy, Mines and Resources&apos; Coordinating Committee on Ocean Mining (DCOM), is the first step in assessing the Canadian offshore f or its resource potential with respect to quantified deposits, known and speculative mineral occurrences. Although this is a subjective evaluation, the potential appears promising. A more detailed resource inventory is required to provide a more certain assessment.

Jan 1, 1984

By Maureen McGuiness

"The pastefill circuit at the Bell Allard Mine in Matagami, Quebec started up in August 1999. The surface pastefill plant produces a cemented paste which is sent underground by gravity through a vertical pipeline in the mine ventilation shaft. Difficulties with paste flow during the start-up highlighted the importance of understanding paste rheology and the effect of operating procedures on line wear. By June 2000, the original circuit had been modified to include a paste pump to transport the paste to the shaft.The steps taken during the paste plant commissioning are discussed. The final flow sheet is presented, focussing on the use of instrumentation to ensure full column flow and proper distribution underground. Resistance modelling and accelerated curing of samples are examined as possible ways of predicting paste resistance to ensure compliance with the mine’s paste specifications.INTRODUCTIONCommissioning a new plant can be difficult and time consuming. The start-up of Noranda’s Bell Allard paste backfill plant was no exception. Since the first day it went into operation, the paste circuit could not meet the tonnage and paste quality requirements of the mine because the paste would not flow by gravity into the vertical pipeline in the mine’s ventilation shaft.Diagnosis of the pastefill problems proved difficult. It was only when the rheology of the Bell Allard paste was understood that the flow problems were solved. To ensure that the paste placed in the stopes meets mine requirements, two methods of paste resistance prediction are being developed."

Jan 1, 2002

By B. Wasmund, B. Haneman, G. Sheehan

Success in implementing new technology for metallurgical processes is not a foregone conclusion: This paper includes a survey of 23 new technology-based metallurgical plant start-ups, in which the authors have identified 7 successes, 9 difficult start-ups, and 7 failures. Success is defined not only as meeting the schedule and budget to the end of mechanical completion; the key goal is a fast ramp up to the full design production level, with minimum plant and equipment modifications required after start-up. This paper sets out the key factors that underlie achievement of a quick production ramp up curve, as determined from the authors&apos; project experiences and a quantitative analysis of over twenty metallurgical plant start-ups, both pyrometallurgical and hydrometallurgical. Thorough test-work and pilot plants, plus appropriate scale-up to the full commercial plant, are key determinants of success in implementing new technology in metallurgical processes. Another critical factor is the number of new elements and their interactions. Project phasing is also particularly important for new technology projects, with appropriate review after each phase to develop a risk mitigation plan for the subsequent phase. New technology projects need committed champions to advance the project in the face of sceptics, but also require dispassionate and unbiased experts to ask the hard questions. As a project evolves, it is important to periodically question the appropriateness of assumptions, as well as to re-assess the relevance and completeness of data from test-work I pilot plants I industrial analogues. Sufficient human and financial resources are required to complete the often arduous implementation phase. During the ramp-up period, the operation generates little positive cash flow; however, significant expertise and capital are required for the de-bottlenecking projects that are often necessary to reach the plant&apos;s design output level.

Jan 1, 2011

By Pascal Lesagel

Life Cycle Assessment (LCA) is a holistic environmental assessment tool that allows the compilation and evaluation of the inputs, outputs, and potential environmental impacts of a product or service throughout its life cycle, from cradle to grave (i.e., from resource extraction and transformation to final disposal, including production and use stages). The relevance of LCA for the mining industry is twofold. First, the mining industry has a role in providing the LCA community the data that allows subsequent evaluations of the life cycle environmental impacts of primary materials such as metals, as well as the environmental comparison of the downstream products of the mining industry with other competing materials for specific uses. Second, the mining industry can use LCA in order to evaluate the environmental impacts of its activities, identify their environmental hotspots and compare the impacts of available technical options. For example, the environmental impacts of different extractive and processing technology can be compared through the use of LCA. This latter use of LCA by the mining industry is less common. This paper discusses the use of LCA to compare sulphidic tailings management options. The paper also presents some of the LCA research challenges that still have to be addressed to increase the relevance of LCA results for the specific context of mining activities.

Nov 1, 2008

By G. E. Norman, A. L. Mckague

"The new smelting process commenced operation in 1978. The pelletizing and sinter plants were replaced with slurry-fed roasters and the blast furnaces with electric furnaces. The existing converter aisle and matte handling facilities remained unchanged.Process DescriptionNickel-copper concentrate is partially roasted in two slurry-fed fluid bed roasters. After gas cleaning, the sulphur dioxide gas is transferred to the acid plant. The roaster product is conveyed to two electric furnaces for smelting to produce a waste slag and furnace matte. The slag goes to the disposal area and furnace matte containing the metal values is processed in the converters for further removal of iron and sulphur.The final matte containing about 75 per cent metal values is shipped to the refinery in Norway.The commercial smelter was designed for 2135 tonnes per day of concentrate, with an availability of 85% . Roasters and electric furnaces were sized at 117 per cent of design, or 1250 tonnes per day on each of two lines. Concentrate storage capacity in the plant is sufficient for two to three days&apos; plant operation.The new smelting process will be discussed under the following headings:Concentrate Slurry HandlingFeed PreparationRoaster OperationRoaster Gas CleaningCalcine TransferElectric Furnace Operation and Process Control Converting and Matte HandlingUnder these headings, process control , equipment changes, and plant performance after three years&apos; operation is reviewed. A brief discussion of accident prevention , and working environment is also included ."

Jan 1, 1984