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By James Pirie

"The major Archean gold deposits in the Red Lake greenstone belt, which have produced over 374 million grams of gold since 1930, occur near the top of the lower komatiitic to tholeiitic mafic to ultramafic metavolcanic sequence. The upper calc-alkalic mafic to felsic rocks form three discrete and separate ediftces overlymg this lower sequence.The gold deposits are classified according to their stratigraphic or lithologic associations into:1) mafic-volcanic-hosted deposits;2) felsic-intrusive-hosted deposits; and3) stratabound deposits.Group 1 and to a lesser extent Group 2 deposits occur within zones of alteration several square kilometres in extent. The nature of this pervasive alteration can be characterized by comparison of petrochemical data from the altered rocks and their fresher equivalents some distance away. The altered rocks have substantial addition of SiO2> CO2, K2O, As and Sb and subtraction of Na20, CaO, MgO and total Fe. Cr, Ni, Co and Zr appear to have been relatively immobile. Hydrothermal alteration and gold deposition probably accompanied early fumarolic activity and continued during subsequent deformation the metavolcanic sequence, with gold eventually being mobtltzed and concentrated into major vein structures to form the present orebodies. The smaller Group 2 deposits formed by emplacement of felsic intrusions into already altered, anomalously gold-bearing mafic metavolcanics, with the heat from the intrusions setting up parasitic hydrothermal systems which mobilized the gold and deposited it along with minor sulphides in fractures in the cooling intrusions."

Jan 1, 1982

By C. L. Emery, A. V. Corlett

"The stress equilibrium is disturbed in a body of rock by a mine opening and is restored by a redistribution of the stresses around the opening. The pattern of the redistribution of unilateral stress around an opening has been established by mathematical analysis and photoelastic measurements. The pattern for multilateral stress is found by superimposition of unilateral fields. The mathematical analysts do not use the elastic moduli as parameters and they are not significant in photoelastic work. The medium is isotropic. The concept of unilateral stress from vertical loading and the classical pattern of its stress distribution around openings does not explain commonly observed failures around the perimeters of mine openings. They show evidence of compression where tension is postulated.When it is recognized that few minerals and perhaps no rocks are Hooke Solids, most rocks must be St. Venant Solids. The components have varying degrees of elasticity and viscosity. The assembly will be-have elastically to rupture under shock loading, but when loaded short of rupture will adjust viscously to equilibrium. Similarly, the highly elastic components may initiate rupture before equilibrium can be established when stress is instantaneously relieved. Polycrystalline adjustments may produce permanent deformation. The mechanics of consolidation, especially in sedimentary deposits, ac-quire a stress component normal to the direction of compaction which can exceed that of the loading. It is one source of prestress. There are others. The principles of prestress design are based on the normal beam reactions, modified by a built-in compression in the lower chord. When the beam is loaded to design limits, the lower chord retains some compression and the whole beam depth is effective in compression. Some of the . common evidences of failure in compression over a mine opening can be duplicated in a prestressed experimental model.When the triaxial stress pattern is recognized and suitable measuring techniques are devised, mine design can be done on a rational basis."

Jan 1, 1959

By J. C. Kingston

Introduction The sliding-form method of erecting concrete structures was first devised and used in the early part of this century by the Sante Fe Railroad Company for the erection of a grain elevator at Santa Fe, New Mexico. A somewhat related principle has been employed for a number of years in shaft lining work and, to our knowledge, was perfected in Butte, Montana, but until the building of the concrete headframe at the Jeffrey mine of the Canadian Johns-Manville Company, Ltd., at Asbestos, Que., the method, as applied to surface structures, was quite foreign to the mining industry in Canada. The current shortage and cost of structural steel shapes has no doubt contributed more than any other single factor to the investigations that have led to the use of reinforced concrete as a headframe building material. Mining men in western Quebec and northern Ontario have shown a great deal of interest in the design and construction of the headframe at the East Sullivan mine in Bourlamaque township, Que., and we have had many queries regarding the methods used and, in particular, for an explanation of the sliding-form principle. This article is written in an attempt to set forth the conditions which were to be met; to explain the construction methods used, and to discuss the economy of concrete headframes as compared with the conventional steel structures with which the mining fraternity is familiar.

Jan 1, 1949

By C. M. Offenhauer

Abstract Zirconium markedly affects the formation of graphite in cast iron and may promote the formation of normal flake gaphite, fine flakes of eutectiform graphite, or spheroid nodular graphite, according to the composition of the Iron and the amount of the zirconium addition. Usually, it is employed in the form of a complex addition agent in order to facilitate its introduction and to guide its effect. The reported applications of zirconium as an inoculant for the production of pearlitic high-strength cast iron indicates that it is most effective as a silicon-manganese-zirconium alloy. Added in this form it reduces chill and minimizes zones of ferrite and eutectiform graphite. In low-sulphur cast iron, zirconium in amounts greater than 0.10 per cent tends to promote the development of eutectiform graphite. These irons are characterized by freedom from primary cementite or normal flake graphite and exhibit very little tendency to shrinkage on solidification. In hyper-eutectic low-sulphur cast iron, zirconium causes the formation of a partially nodular graphite structure. A combination of magnesium with silicon-zirconium alloy was found to produce completely nodular graphite structures without the hazards associated with the addition of elemental magnesium.

Jan 1, 1949

By R. Bashir, J. F. Hatley

ABSTRACT Northern Saskatchewan boasts some of the world’s largest known high-grade uranium deposits. The successful mining of these deposits cannot be accomplished without overcoming technical challenges, however, which include high grade of the uranium ore, specialized mining methods to deal with groundwater at high pressures, and poor ground conditions. This paper discusses the various mechanisms of inflows at three of Cameco Corporation’s sites in northern Saskatchewan. The risk of inflows is quantified in terms of unique challenges due to hydrogeological conditions, rock mass integrity, and uncertainty in geological conditions. Strategies in the case of an inflow are also briefly described.

Jan 1, 2013

By M. C. Harris

The past twenty to thirty years have seen unprecedented research activity aimed at understanding the performance of flotation froths. In 1990, Finch and Dobby coined the term froth recovery factor, Rr, to represent the efficiency of the froth in delivering particles from the pulp-froth interface to the concentrate. Originally defined for flotation columns, Rr has also been found useful in modeling mechanical flotation cells, and a number of techniques, based on quite different approaches, have been developed for measuring the froth recovery in industrial flotation cells. None of these techniques is universally successful. This paper reviews the concept of the froth recovery factor, and the basis of each of the techniques that have been proposed to measure Rr, and examines the reasons for this parameter being so difficult to pin down. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By C. E. Baltzer

This is the fourth in a series of coal technology reviews being prepared. in accordance with a recommendation voted by the Coal Division C.I.M. in session at the Jubilee Meeting, Vancouver, 1948, that the Department of Mines and Resources be requested to arrange for publication by the proper Government authority of a Quarterly Review of Coal Technology for distribution among those concerned in the production and use of coal in Canada. Copies of the first review, which appeared in the November, 1948, BULLETIN, pp. 612-614, of the second review in the June, 1949, BULLETIN, pp. 272-275, and of the third review in April, 1950, BUL-LETIN, pp. 1,9?3-196 (also, respectively, in Transactions, Vol. LI, 1948, pp. 262-264 Vol. LU, 1949, pp. 117-120, and Vol: LIU, 1950, pp. 133-136), were distributed by the Dominion Coal Board and are still available on request. In this review, the first in the series in the field of combustion, development and trends during the period approximately from World War II to the present time are described and therefore the presentation is general. Later reviews will particularize developments in relation to the range of coals available in Canada.-ED. INTRODUCTION THE utilization of coal in heat and power producing equipment has become of paramount importance to the coal industry in maintaining stable and profitable markets. In the past, the chief concern was with mining, transportation, and overall supply problems, but modern conditions demand interest in and knowledge of all phases of the product, from coal in situ to its ultimate disappearance in the form of products of combustion. Even the last mentoined factor has caused complications, as is shown by current widespread activity in the field of smoke abatement

Jan 1, 1951

By P. R. Geoffoy, T. Koulomzine

"The discovery of the Mogador deposit concealed by 100 feet of overburden was the result of combined application of geological reasoning, ground geophysical surveys, studies of glacial float and extensive diamond drilling. The ground was acquired because it lay on the projected intersection of the Manville and Laflamme River faults. Systematic ground prospecting led to discovery of mineralized floats. A first unsuccessful exploration campaign lasted several years and consisted of 137 drill holes.In 1951 the boulder nests were reexamined and an associat'on of the mineralized float with boulders of a granodiorite, unknown in outcrops of the district, was established. Consequently, ground magnetic surveys were extended and re-interpreted, and a large anomaly interpreted as corresponding to a batholith was outlined. The existence of the batholith was immediately confirmed by drilling and the Mogador deposit discovered in third hole of new drilling programme in a zone of fractured volcanics paralleling southern contact of batholith.The Mogador deposit is a complex replacement of silicified volcanics by pyrite, pyrrhotite, sphalerite, chalcopyrite and galena carrying values in silver and gold. A total of 1,230,000 tons has been indicated, most of it now classified as fully developed proven ore."

Jan 1, 1960

By A. E. M. Warner, P. J. Mackey

"In 1988, two of the present authors Warner and Vahed [1] were amongst several co-authors on a seminal paper reviewing nickel pyrometallurgical operations of the era. Given that significant changes in the nickel industry have occurred since that time, including the overall political landscape, technology, the overall world energy picture, the countries sourcing nickel and finally the nickel market itself, the present authors considered it timely to provide a 2015 update. In 1988, total world nickel production from sulphide and laterite sources, including production in the former "Centrally Planned Economies"- was about 0.86 million tonnes/a, while in 2014 total world nickel production reached an all-time high of almost 2 million tonnes/a - some 230% higher. On the other hand, while in 1988, about 94% of world nickel was produced pyrometallurgically and of the order of 33% via laterites, today, about 88% of nickel is by pyrometallurgy, with some 41% from laterites, thus showing that more nickel is now sourced from laterites, a trend which is expected to continue.During the period under review, new processing technologies were developed and introduced, along with substantial improvements in both the technologies employed and the scale of operations. Significant productivity gains have been achieved in sulphide pyrometallurgy in part through more efficient mineral processing, particularly in pyrrhotite rejection, and the use of ever larger-scale process equipment. This made it possible to treat lower grade and more complex ores. The significant game-changer from a production perspective was the introduction in the early 2000s of nickel pig iron (NPI) in China via modified iron blast furnace smelting, an old technology long ago cast aside by other nickel producing countries. With the exception of the emergence of this new NPI capacity in China, in the laterite industry modernization and expansion of existing operations has been employed to gain productivity, to cut costs and/or offset the effect of declining ore grades. The NPI technology development has become a game changer in the traditional global supply and demand relationship, opening up a new frontier to supply nickel to low grade utility steel producers. One other key nickel development was the Indonesian ban on nickel ore exports effective in January 2014, thus effectively curtailing NPI production at existing Chinese plants, but on the other hand, potentially prompting new smelting facilities in Indonesia. This paper reviews and updates major pyrometallurgical sulphide and laterite operations worldwide, including changes in nickel extractive metallurgy. It also provides a brief review of new developments in pyrometallurgical operations, with special focus on the NPI process and presents an outlook of the potential future direction of the industry."

Jan 1, 2015

By R. W. Brigstocke

History The birth of the mining industry of Canada took place about 1670. According to Salone (Salone E., La Colonisation de la Nouvelle France, page 205) the first discovery of ore in the country was made by an iron-master, Monsieur de la Potardiere, near Trois Rivieres, Quebec. Under French rule some prospecting was done; but at this time no one seemed to consider the working of mines practicable. It was not until the time that Begon became Intendant, when the Marquis of Vaudreuil was Governor, that mining was attempted. Begon was a patron of industrial arts and did his best to promote home manufactures. The mining industry was developed under his regime and discoveries of copper and lead ores were made in 1730. About this time the St. Maurice Forges were erected to treat bog-iron ore, and they were in operation for many years. Prior to 1747, iron pans to the value of £21,000 were manufactured, together with bar-iron and plough-shares. About 1769, that is, ten years after the conquest by Wolfe, stoves and other articles, and, later, potash kettles, appeared. What is still more interesting to us-or was, at least, to General Wolfe-is that cannon balls made at the St. Maurice Forges delayed his operations. A map dated 1744, a copy of which appears in the report of the Ontario Bureau of Mines for 1913 (Vol. XIX), indicates the extensiveness of the wanderings of the French and also shows the location of the lead mine on the east shore of Lake Timiskaming. Bog-iron ore was turned into metal, with charcoal for fuel, at Norman-dale, Norfolk county, Ontario, in 1813, and at Clementsport, Nova Scotia, in 1825. In a volume published in 1672, reference is made to the occurrence of coal on the Atlantic seaboard, and in 1677 Monsieur Duchesneau, the Intendant, levied a royalty of twenty sous per ton on all coal taken from Cape Breton.

Jan 1, 1932

By F. D. Forgeron

"ONE OF THE FIRST DOCUMENTED APPLICATIONS of soil geochemistry in the Canadian Shield was that carried out by Chisholm in the Kenora district in 1949. This survey proved successful in outlining sulphide-associated gold veins utilizing cold-extractable metals. Since then, mining companies, government agencies - both provincial and federal - and universities have conducted soil investigations. Some of the results are documented in publications, others are on open file in provincial and federal mines departments and, unfortunately, many other investigations with both successful and unsuccessful results are buried in company files or have been discarded. This paper deals with soils within the scope of chemical studies of overburden in the Canadian Shield. The subject is a broad one and some definition is required. The soil investigations discussed herein are those aimed at the testing of specific targets more or less in the source area. This definition distinguishes soil investigations from other overburden studies which commonly monitor metal accumulations at some substantial distance from the metal source. Naturally this distinction is relative, because in many instances there is overlap."

Jan 1, 1971

By H. Al-Kazzaz

The 2-mm butt joints of ZE41A-T5 sand castings were laser welded using 1.6 mm EZ33A-T5 filler wire and a continuous wave Nd:YAG system at a power of 4 kW, surface defocusing and various welding speeds, Compared with the base metal, the fusion zone showed significant grain refinement due to high cooling rate, No grain coarsening was observed in the heat affected zone (HAZ). The porosity area percentage and total solidification crack length in the fusion zone (FZ) were reduced as the welding speed increased from 4 to 7 m/min, Fusion zone area, total penetration depth, and weld width decreased with increased welding speed, The hardness in the FZ was similar to or higher than the base metal after a natural aging of about one year, but there was a drop in the hardness of the HAZ, The HAZ width decreased with increasing the welding speed, Tensile test showed that a joint efficiency of approximately 75 ? 90 % was obtained.

Jan 1, 2005

By D. D. Macdonald, G. Engelhardt

The accumulation of damage due to localized corrosion [pitting, stress corrosion cracking (SCC), corrosion fatigue (CF), crevice corrosion (CC), and erosion-corrosion (EC)] in complex industrial systems, such as power plants, refineries, desalination systems, etc., poses a threat to continued safe and economic operation, primarily because of the sudden, catastrophic nature of the resulting failures. Of particular interest in managing these forms of damage is the development of robust algorithms that can be used to predict the integrated damage as a function of time and as a function of the operating conditions of the system. Because complex systems of the same design rapidly become unique, due to differences in operating histories, and because failures are rare events, there is generally insufficient data on any given system to derive reliable empirical models that capture the impact of all (or even some) of the important independent variables. Accordingly, empirical models have generally failed to provide a robust basis for predicting the accumulation of corrosion damage in complex systems under realistic operating conditions. The alternative prediction philosophy is determinism, in which the development of damage is described in terms of valid, physico-electrochemical mechanisms with the output being constrained by the natural laws. The differential damage is then integrated along the corrosion evolutionary path for the system (i.e., over the future operating "history") to yield the desired integrated damage, which is the quantity that is most useful to an operator. In this paper, we review the theory of predicting corrosion damage within the framework of Damage Function Analysis (DFA), with particular emphasis on the pitting of aluminum in chloride solutions and on the accumulation of damage from SCC in Type 304 SS components in the primary coolant circuits of Boiling Water (Nuclear) Reactors (BWRs). These cases have been selected to illustrate the various phases through which localized corrosion damage occurs.

Jan 1, 2005

By R. A. McIvor, R. Levac

"The Stobie No. 7 shaft, 14 ft diameter, double- drum skip hoist, was installed at the INCO Limited Frood Stobie Complex in 1942. Figure 1 shows the hoist layout. The hoist was originally equipped with babbitted journal bearings on the main drum shaft and pinion gears. In 1990, the hoist was modernized with a new braking system, two new 2000 hp D.C. drive motors, a thyristor armature supply and a PLC control system. The new drive motors were connected to the drive pinion gears with a gear type flexible coupling. The pinion gear journal bearings were refitted during the refit in 1990 as the existing babbitted bearings showed signs of wear. The pinion gear journal bearings had always run warm and had external cooling applied during the warm summer months. Figure 2 shows the journal bearings on the pinion shaft. The skip hoist main bull gear and two pinion gears were replaced in 1997 because of cracked bull gear spokes. New drive couplings were installed on the pinion gears and the pinion journal bearings were modified to allow some self-aligning properties to try to reduce the heating and wear on the babbitt. The modifications did not significantly reduce the heating problems and a decision was made in the spring of 1998 to convert the bearings to self-aligning, anti-friction-type bearings.The traditional roller bearings used on double helical pinion drive gears in hoist applications has always been double-row spherical roller bearings due to their high load-carrying capacity and misalignment allowances.Unlike single helical gears, double helical arrangements do not exert axial thrust on the pinion gear bearings, therefore, both bearings in the pillow blocks must float easily with any pinion displacement. Drum misalignment, thrust bearing end play and a multitude of other influences causes continuous axial displacement of the pinions when in operation. This constant displacement or “hunting” of the pinion gear to maintain its centre on bull gear often exceeds the axial clearance limits of spherical roller bearings thus resulting in a continuous sliding motion of the bearing outer rings against the housing seats. With time, the housing fit eventually wears, creating an out-of-round condition for bearing housing (maximum allowable cylindricity tolerance is IT4/2). When this happens, the pillow block housings must be replaced or re-machined to specification. Premature bearing wear and overheating will occur if a housing out-of-round condition is encountered."

Jan 1, 2001

By Brent C. Jellicoe, Phil Robertshaw, J. Murphy, Peter Williamson

Kimberlites and associated diamonds have been the focus of extensive exploration in central Saskatchewan since 1988. During 1989, Uranerz Exploration and Mining Limited identified 71 shallow magnetic anomalies in the Fort a la Corne area from detailed aeromagnetic surveys. By the end of 1991, 18 of these targets had been proven, by drilling, to be kimberlite bodies encased within Cretaceous sedimentary strata. From 1991 to 1997, the number of drill-confirmed kimberlite bodies increased to 69. Our current view, drawing on an integration of geophysical and geological information, is that the kimberlites are composed of individual bodies and multi-vent clusters of coalesced bodies, all apparently constructed of stacked, temporally distinct layers of pyroclastic crater-facies kimberlite. Diamond recoveries and geochemical results from associated heavy minerals at Fort a la Corne remain highly variable, although continued minibulk sampling is expected to improve the estimation of diamond grades for the most prospective bodies.

Jan 1, 2001

By Staff

Introduction As the Sherritt Gordon property is still in the development stage, . it is rather difficult to write a proper account of the mining methods and milling practice that will be used. While the general scheme of operation will remain the same, there will undoubtedly be many minor changes to meet special conditions which we cannot forsee at the present time. Most of the work accomplished to date has followed the usual routine of preliminary development in the Canadian North. However, we have learned a few things which might be of use to others operating under similar conditions. The most important of these is the saving in power cost made possible by the use of Diesels as against steam power when using wood fuel, and the movement of freight by tractors when rail transportation is not available. Location The property i6 located about 90 miles north of The Pas, or 40 miles northeast of the Flin Flon mine. A branch line from Cranberry Portage, on the?C. N. railway, between Flin Flon and The Pas, connects the property with the outside.

Jan 1, 1930

By M. J. Collins

"Autoclaves were first used in the metallurgical industry in 1893 to recover alumina from bauxite. In the 1940s and 1950s, several high temperature and pressure processes were invented in the laboratory of Professor Frank Forward at The University of British Columbia, in parallel with advances in equipment and processes by the Chemical Construction Corporation. Sherritt Gordon Mines Limited enlisted these groups to help develop the nickel sulfide ammonia leach process that was commercialized in 1954. Autoclave processes that have since been commercialized include high-pressure acid leaching of laterites, zinc pressure leaching, and pressure oxidation of refractory gold feedstocks. RÉSUMÉ En 1893, l’industrie métallurgique est la première à utiliser les autoclaves pour l’extraction de l’alumine dans la bauxite. Dans les années 1940 et 1950, plusieurs procédés à haute température et à haute pression sont inventés dans le laboratoire du Pr Frank Forward de l’université de la Colombie-Britannique (UBC) ; parallèlement, la Chemical Construction Corporation fait de grands progrès en matière d’équipement et de procédés. Sherritt Gordon Mines Limited fait appel à ces groupes pour qu’ils aident la société à développer le procédé de lixiviation du sulfure de nickel dans de l’ammoniaque, commercialisé en 1954. Les procédés de lixiviation en autoclave commercialisés depuis incluent notamment la lixiviation acide à haute pression de latérites, la lixiviation sous pression du zinc et l’oxydation sous pression des matières premières de l’or réfractaire.INTRODUCTION Autoclaves are chemical reactors that are built to contain processes taking place at elevated pressure. They are used in metallurgical refineries throughout the world to take advantage of the increased reaction kinetics and different reaction products that can be obtained in aqueous systems above the boiling temperature at atmospheric pressure. The word autoclave comes from the French “auto” and the Latin “clavis” and literally means self-locking—that is, the core distinguishing feature of an autoclave is that it includes a means for pressure regulation (e.g., a pressure relief valve). Denis Papin (Figure 1a), one of the inventors of the steam engine, was the first to make use of a safety valve to control steam pressure. He is credited with inventing the autoclave in 1679. Papin’s “digester” (Figure 1b) was a type of pressure cooker that was originally used to liquefy bones. Most commercial autoclaves are horizontal, multicompartment vessels with mechanical agitation, as shown in Figure 2a; however, the steam-agitated Pachuca vessels used to leach laterite ore in Moa, Cuba (Figure 2b), are also classified as autoclaves according to the self-locking definition provided above."

Jan 1, 2018

By Yun-Jie Wei

Seismic areas were in the eastern margin of the Qinghai-Tibet plain, whose structures were complicated, mainly composed of Maowen fault, Yingxiu fault and Pengxian-guanxian fault. The rapid rise of the Qinghai-Tibet plain led the crustal material of the eastern edge to move to the southeast along the faults on a large scale since the late Cenozoic; Minshan block structure and Long Men Mountain tectonic zone represented the strong nappe thrust movement as the east boundary of Chuanqing slip block; the stress was accumulating when squeezed, which to a certain extent resulted in breakdown of the crust, and earthquakes. The shock speed, high-energy accumulation, and the reversed dextrorotation of the earthquake fault characteristics et al. happened, which caused the development of secondary geological disastersts. According to on-site investigation, the typical geological disasters had thrust rock collapse, the instability deposit, the revival of potential debris flow et al. whose genetic model had been analysed.

May 1, 2009

By S. A. L. Read

"The intact rock constant, mi, is one of the three basic input parameters required for the widelyused Hoek-Brown failure criterion. Values for the constant should ideally be determined by statistical analysis of laboratory test data. In this paper the influence of the inclusion or exclusion of tensile test data on derived values is discussed. We firstly investigate the relationship between direct tensile strength (DTS) test values and Brazilian tensile strength (BTS) test values based on a literature search, finding that the correlation between the two test types is DTS = 0.9*BTS, independent of the lithology being tested. Secondly, using the shear strength database of Douglas (2002), we examine the influence of confining pressure range and the inclusion or exclusion of DTS and BTS test values on calculated values of mi.Chief amongst the influences was the exclusion of tensile data in the calculation procedure, particularly when the Hoek triaxial confining stress range requirement (?3?max = 0.5?c) was not satisfied. Based on a reasonable 1:1 relationship between R (the ratio of unconfined compressive to tensile strength), use of actual tensile data in the calculations for the Hoek brown failure criterion is considered to be a simpler and more robust approach to the use of a tensile cutoff based on empirical criteria such as that of Fairhurst (1964). We advocate the fitting a failure curve using compressive and tensile test data as the most reliable means of calculating mi, while at the same time satisfying requirements as originally advocated by Hoek relating to the appropriate triaxial confining stress range (?3?max = 0.5?c) and sufficient (>5) evenlyspread data points. In the absence of triaxial data the use of R provides a practical means of obtaining estimates of mi that are more robust than guideline values."

Jan 1, 2015

By R. Stauffer, S. Lindsay

"Sherritt Gordon Mines Limited utilizes pressure hydro-metallurgical techniques to recover nickel, copper and cobalt from su1phidic concentrates, mattes and various other metal-bearing materials.A brief description of the nickel refinery operation is given. In the nickel refinery process, an ammonia pressure leach is employed to treat the feed materials to dissolve the non-ferrous metals as their respective ammine complexes. The resulting leach solution goes through a series of steps which removes copper as copper sulphide and further purifies the solution prior to nickel precipitation by hydrogen reduction. The reduction end solution, containing the cobalt which was originally present in the leach solution as well as residual nickel, is treated with hydrogen sulphide. The resulting nickel-cobalt sulphide precipitate feeds the soluble cobaltic ammine process, which separates the nickel and cobalt and recovers the cobalt as a pure powder.A detailed description of the cobalt recovery process is given. Included are the various steps, comprising: acid leaching of the mixed sulphides, solution purification, ammine complex formation and cobaltous oxidation, two-stage nickel precipitation, cobalt conversion and reduction. A brief description of cobalt powder handling is included, along with typical physical properties and chemical analyses of the cobalt product. In general, the purpose of this paper is to describe the present plant practices employed in the recovery of cobalt as a by-product of the nickel refinery operations."

Jan 1, 1967