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By J. S. Redpath

There appears to a definite trend toward the hoisting of greater tonnages from greater depths. There is every indication that this trend will continue and we feel that improvements in the design, fabrication and installation of mine guides will be of significant importance in the future. The present state of the art in mine-shaft guide systems is reviewed and the parameters required for improvement are derived in this paper. Finally, a proposal is made for a new steel guide system which meets the parameters and is economical to fabricate and install.

Jan 1, 1977

By Bennett McLaughlin

AGNICO-EAGLE started sinking the Penna Shaft in 1995 with a hoisting plant capable of hoisting 1,800 tonnes per day from a 2,240 metre deep shaft. Exploration success lead to the installation of a hoisting plant capable of extracting 4,500 tonnes of ore and 1,800 tonnes of waste per day from a depth of 2,210 metres. The introduction of a new rope selection factor, permitting a safety factor of 4.0, represented the breakthrough required for a cost-effective project. This paper describes the process taken to introduce the new rope selection factor and its impact on the original plant.

May 1, 2001

By R. Stratton-Crawley, S. W. Wilson

"Inco's Matte Separation Plant is a unique mineral processing facility having no process tailings stream. Each product is a high-grade concentrate with strict assay specifications which are defined by the downstream refining route. The most recent column application in the flowsheet, copper scavenging in the production of a high quality nickel concentrate, is described in detail. Testwork in pilot-scale columns (0.038 m, 0.051 m and 0.10 m in diameter) was used to develop a model of the copper scavenging system. This data was then used to simulate the performance of plant-scale equipment. The relationships thus established were confirmed by a series of plant tests in a 1.8 m diameter column. Column results consistently exceeded conventional cell performance. The modelling was extended to assess full plant production requirements and, as a result, a 2.1 m diameter column was specified for this application. Engineering design for this column is currently underway and the column is scheduled to be commissioned later in 1991.INTRODUCTIONMatte SeparationINCO's Matte Separation Plant is a part of the Copper Cliff Smelter complex near Sudbury Ontario. The flowsheet and the development of column flotation within it have been described previously (Feeley et al., 1987, Wilson et al., 1989). The plant feed is a synthetic Bessemer Matte from the Nickel smelter. This matte is slow cooled to promote grain growth and typically assays 46-52% Ni, 23-27% Cu. These elements are present primarily in sulphide form (Ni3S2 and Cu2S respectively) with some metallic alloy also precipitating from the sulphur deficient matte. Minor amounts of iron, precious metals, and nuisance elements are also present.The matte separation process is, in concept, relatively simple. Following magnetic removal of the metallic alloy from the feed, the flowsheet is designed to float a high grade copper concentrate from the nickel sulphide matrix. A simplified flowsheet of the process is shown in figure 1."

Jan 1, 1991

By G. K. Quainoo

In the automotive industry, the awareness to meet Corporate Average Fuel Efficiency (CAFE) standards has evolved the need to reduce vehicular weight in new automobile designs, with the overall goal of reducing gas emissions into the atmosphere (Kyoto protocol), One efficient method has been to use lighter materials such as aluminum in outer body panels, Heat treatable AA6111 is one of the materials employed due to its unique combination of formability, paint bake strengthening and superior corrosion resistance characteristics, Researchers have applied various thermo-mechanical processes on 6000 series aluminum alloys and have found an improvement in the mechanical properties of these alloys, For a formed and painted automobile panel, the final mechanical properties involve a combination of strength components arising from cold work, strain aging and precipitation minus recovery. In this study, the evolution of microstructure resulting from the interaction of cold work and precipitation in AA6111 has been studied by means of transmission electron microscopy (TEM) after subjecting samples to various heat treatments, tensile testing and differential scanning calorimetry (DSC), This has been done to understand the evolution of microstructure and its influence on the properties of the alloy, The results show a considerable improvement in strength with a corresponding increase in strengthening precipitates with increasing level of cold work in the alloy. DSC results following the application of various levels of cold work also show acceleration in the precipitate phase formation, as precipitates are observed to form at lower temperatures, with increasing level of cold work/

Jan 1, 2005

By J. Fournier, D. Fortin, F. Robichaud

Since milling began in 1988, the Laronde mill has been expanded several times, the most recent, increasing the milling rate from 5 000 to 7 000 mtpd. Laronde uses SAG/ball mill grinding followed by copper and zinc flotation circuits. A cyanidation/Merrill-Crowe process recovers the remaining gold and silver in the flotation tails in order to cope with high silver/gold ratio associated with the discovery of the Penna shaft. Since the commissioning of the Merrill-Crowe refinery in 2000, several modification and expansion projects were performed to reduce health and safety hazards. Remarkably, several of these improvements have contributed at increasing productivity and Net Smelter Return of the refinery while reducing worker's injuries. In 2004, the refinery was audited to evaluate and quantify the circuit performance. Metallurgical and mechanical operating conditions of the refinery are now understood and areas for further improvements are well defined. This paper describes some of the factors that have contributed to this improvement and describes how ergonomics and recovery can further be improved.

Jan 1, 2005

By C. I. Garcia, G. Zhou, W. Gao, A. J. DeArdo

The development of X-100 and X-120 linepipe steels was investigated using a series of low-carbon Mo-Nb-B steels. The laboratory steels were vacuum melted and processed using advanced thermomechanical processing (TMP) philosophies. Prior to the laboratory hot-rolling experiments, the grain coarsening temperature, the conventional T95 and T5 start-stop recrystallization temperatures and the transformation behavior of y were studied using a computer-controlled high temperature deformation MTS-458 and a Theta-IV High Speed dilatometer systems. The results from these experiments provided the guidelines for the design of the laboratory hot-rolling TMP processing experiments. The mechanical properties of the experimental steels showed yield strengths in the range 700-850 MPa and CVN impact properties of over 80 J at -20°C. The best balance of mechanical properties was obtained by using CCR+DQ+Tempering treatments. The major microstructural features responsible for the observed mechanical properties in order of importance were: a) substructural refinement associated with lower bainite, b) dislocation strengthening, c) fine recrystallized ferrite, and d) small amounts of retained austenite. Fine Nb(C,N) precipitates formed in ferrite were observed, however their contribution to the strength was minimum. Most of the Nb(C,N) precipitation took place in austenite. This precipitation was used to exert microstructural control of austenite during hot rolling. The physical metallurgy and optimum TMP to achieve the mechanical properties are detailed in this paper.

Jan 1, 2005

By Hyung Sup Choi

The preparation of high-purity zirconyl compounds was studied in order to develop an economical process for obtaining pure zirconium via the caustic fritting of zircon sand. The direct dissolution of caustic frits with concentrated hydrochloric or nitric acid at 80c. followed by the addition of a small amount of acidified gelatin, gave high-purity zirconyl chloride or nitrate. The addition of a small amount of gelatin caused a mutual flocculation between colloidal silica and gelatin. The precipitation of this silica floc markedly lowered the content of silica in the product. The silica content of the compounds (or solution) so produced, generally less than 100 ppm., was sufficiently low for tributyl phosphate extraction for nitrate solutions. It was found that the degree of purification de-pends not only on the procedures employed but also on the nature of the frit itself. Silica was more effectively eliminated from the fritted product produced at higher temperatures, and less silica was present in the com-pound prepared from the frit produced in a shorter heating time. In order to ascertain the nature of the

Jan 1, 1965

By A. E. Boone

"The paper presents critical areas in which improved coordination of effort by industry, government and sup-pliers will be essential to continue the growth record of the Canadian mining industry into the 'seventies'. The analysis includes: exploration, production, mining methods, research and development, markets, management and industrial relations. Performance objectives are suggested where tangible results can be measured. The author suggests the methods by which the 'seventies' can be the greatest decade in the history of Canadian mining. It is indicated that a national mineral policy is essential to the Canadian mineral industry."

Jan 1, 1970

By G. Barr

"The Polymetallic Twin Metals Project deposits in Northern Minnesota are being developed by Twin Metals Minnesota. Amongst the flowsheet alternatives being examined at a prefeasibility study level is one involving flotation of a bulk concentrate followed by high temperature autoclaving of the concentrate using the PlatsolTM Process to solubilize all the valuable metals in the concentrate (Cu, Ni, Pt, Pd and Au). Autoclave operating conditions have been established in which recoveries of all the pay metals are in the 92 to 99% range, and the autoclave residence time has been reduced to an hour. The stability of the precious metals in solution after autoclaving has been assessed, as well as the impact of internally recycling process liquors to the feed to the autoclave.INTRODUCTIONPlatinum group metals (PGMs; platinum, palladium, rhodium, ruthenium, iridium and osmium) are traditionally recovered from their ores by production of a high-grade concentrate by flotation and/or gravity concentration followed by smelting of the concentrate. Concentrates are smelted to remove nonsulphide minerals and converted to remove iron and sulphur. The resulting high PGM grade matte is processed hydrometallurgically to leach the base metals, leaving a residue with a very high grade (20-40%) PGM concentrate for final refining to individual PGMs. Due to the complexity of this process and its high capital cost, this process can only be applied economically to high grade PGM ores. Lower grade PGM concentrates might be accepted as copper and nickel concentrates but may not yield attractive payment terms for the PGMs. The mineralized Duluth Gabbro region of Minnesota hosts several low grade base and PGM deposits and Twin Metals Minnesota is working to develop the Twin Metals Project deposits. Earlier studies at both pre-feasibility and feasibility level, by other mining companies, have failed to yield an economically viable project based on the traditional process. It is possible to produce a saleable copper concentrate from these ores, but economic recovery of nickel and PGMs into saleable concentrates proved elusive.In the late 1990’s and early 2000’s the Platsol™ process was developed at SGS in Lakefield, Ontario (at the time Lakefield Research Limited) for the NorthMet deposit (also within the Duluth Gabbro) owned by PolyMet Mining. The process developed was a high temperature chloride-assisted pressure oxidation process capable of dissolving simultaneously the base metals (Cu, Ni, Co, Zn), gold and the PGMs."

Jan 1, 2012

By Oliver Hall

This paper sketches the mining at Noranda as it would be sketched to a visiting engineer. It does not follow quite the usual form, but is presented somewhat along the lines of a conversation. TO give the mining at Noranda its proper perspective, it is necessary to sketch the whole picture and outline: 1. History 2. Metallurgical Problems 3. Exploration 4. Mining Methods 5. Mining Details 6. Filling 7. Pillar Extraction 8. Costs HISTORY Noranda is a relatively young enterprise, with much of the personal character of its founders woven into it. The name Noranda is an abbreviation of Northern Canada and the name has been a happy one for an enterprise based on northern resources, tenacity and courage. The discovery credit goes to Ed. H. Horne. This intrepid prospector returned again and again to his sulphide discoveries on the shores of Osisko lake and, in 1922, after ten years of prospecting, succeeded in interesting S. C. Thomson and H. W. Chadbourne in his discoveries. The early exploration by L. K. Fletcher, from 1922 to 1925, for Thomson and Chadbourne, indicated promising, but somewhat perplexing, ore conditions. Mr. E. Hibbert and Mr. H. L. Roscoe rook on the task of preparing the mine for production and building a smelter in 1926, and this difficult task in this isolated area made steady progress and the smelter was blown-in in December, 1927.

Jan 1, 1937

By B. W. Clyburn

"Coals from the Corporation's Lingan and No. 26 mines are classified as high-volatile A bituminous, with a very low inherent ash and containing a/l essential properties to provide metallurgical coal, with the exception of a high sulphur content. Only through proper cleaning at low specific gravity can the pyritic sulphur fraction of the coal be liberated to an extent where final sulphur meets coking standards. This first section of the paper deals with the operation of a Dutch State Mines heavy-media cyclone circuit to achieve an actual separation in the region of 1.30 specific gravity. A discussion of the parameter of control which must be applied along with an appraisal of the results obtained is included in the paper.IntroductionVery high fluidity and unusually low ash are the outstanding characteristics of coal from Devco's mines in the Harbour seam of the Sydney coal field.However, sulphur content, mainly pyritic, ranges from 1 to 2.5070. To obtain the low and consistent sulphur level required in metallurgical coking coals, preparation at low specific gravity is required .Metallurgical coke is used as the fuel in an iron blast furnace. Its sulphur content largely determines the quantity of slag required to remove it and therefore influences furnace productivity and unit costs.Typical data on the various coal properties of importance in the production of coke are included in Table I. Necessity of Low-Gravity SeparationThe design of any coal preparation plant requires the study of washability properties of the coal to be treated to determine the quantity and quality of coal produced at a given specific gravity along with the difficulty in accomplishing that separation.Their low ash content allows the important washability aspects of Harbour seam coals to be represented by sulphur! specific gravity curves (Fig. I). This particular example indicates that a yield of 54.5% is attained, at a sulphur content of 1.20%, for a perfect separating device operating with a 1.29 S.G. cut point.Material rejected from this separation still contains usable coal, which is recovered as middlings by separating at a higher gravity."

Jan 1, 1980

By A. C. Elliott, A. J. Lafreniere

THE Hamilton Works of The Steel Company of Canada is a fully integrated steel plant with an annual capacity of three million tons. Located on the south shore of -Hamilton bay, it is in the centre of Hamilton's industrial belt. The heavy concentration of industrial activities found in this area, accompanied metallurgical well-known sources of pollution which are normal to urban areas is creating a pollution problem which concerns both industry and the general public. The Steel Company of Canada has recognized this problem and, accordingly, has adopted the policy of integrating suitable pollution control devices into its new installations. Much effort is also being expended to control the emissions of air contaminants from the existing equipment. At the Hamilton Works, there are two main sources of metallurgical dust emissions to the atmosphere -the Open Hearth furnaces and the Sinter Plant. Of these two, the Open Hearth furnaces are, undoubtedly, the largest single source of

Jan 1, 1962

By C. G. Harris, R. Sluyter

The purpose of an undercut is to undermine a block of ore which will then proceed to cave into draw holes just below the undercut. Undercut-ting is the final and most vital phase in the development of an ore block. Since its purpose is to undermine and induce caving into a block of ore, great care must be exercised to avoid premature caving by removing only enough rock to permit undercut development to proceed. Several undercutting methods, used over a twenty-year period, are re-viewed and their suitability is com-pared with ideal requirements.

Jan 1, 1960

By W. L. Murphy

The Star Lake property, located 115 km northeast of La Ronge, Saskatchewan is underlain by metamorphosed andesitic tuffs and flows which have been intruded by the dioritic to granitic Star Lake Pluton. Gold mineralization on the Star Lake property was first discovered at Ru h Lake by E. Beveridge in 1959 and by M. and E. Hird in 1961. In 1960 E. Partridge discovered Kahn 18 and Kahn 28. In 1982 the SMDC-Starrex joint venture completed geophysical and geochemical urveys including magnetics, VLF, IP/Resistivity, vegetation, bulk till and oil sampling, followed by drill testing of pecific targets. To date the most ignificant depo it is the 21 Zone which contain drill indicated reserves of 230,000 tons grading 0.5 oz/ton Au . The 21 Zone con ists of quartz with 5-10% (locally > 30%) drusy pyrite, minor chalcopyrite and trace amounts of scheelite, chalcocite and arsenopyrite. The 21 Zone is enclosed by a 25-50 m wide band of mylonitized monzonite. The mylonite occurs in the central portion of a 300 m wide northeasterly trending zone of brittle deformation .

Jan 1, 1986

By Norman B. Davis

Introductory Feldspar is one of the most important mineral products consumed by the various branches of the ceramic industry. In the manufacture of table ware, electric porcelain, floor tile, and enamels, it supplies the chief fluxing ingredients necessary to bond the other more or less inert materials together when moulded into desired shape and fired in a kiln. Feldspar is used in the manufacture of bottle glass as a means of introducing alumina in a form easily assimilated. It is also used in certain scouring soaps particularly designed for cleaning enamel and glass surfaces. Feldspar, as it finds its way to the trade, is not a single mineral but is rather a mixture of various proportions of the feldspar silicate series, either in natural intergrowth or blended in the milling process, to produce a desired result. It is often further modified by the presence of quartz in amounts up to 30 per cent. The table on the next page gives typical commercial analyses of feldspar from various sources. Canadian feldspar produced to date has consisted mainly of the high-potash, relatively low-soda, variety, and has enjoyed a good market in the United States for the manufacture of enamels, electric porcelain, and vitrified table-ware. About eighty per cent of the output has been exported to the United States, but, with increased milling facilities in Canada and changes taking place in domestic United States sources of supply, the proportion exported will be reduced next year.

Jan 1, 1931

By J. Cayouette, C. Bolduc, P. Blatter

"The LaRonde mill was commissioned in 1988 and began treating ore from the Penna shaft in 2000. The mill has been expanded to accommodate 7,500 t/day, but ramped down to 6,000 t/day since the deep extension began. The process recovers gold, silver, and base metals. In 2008, the Goldex plant began trucking gold-pyrite concentrate to a treatment plant feeding pulp to the LaRonde mill, increasing gold output by 40,000 oz. In 2009, the high-grade Lapa ore processing facilities were annexed to the LaRonde plant, increasing gold output by 120,000 oz. This paper outlines the metallurgical considerations related to the treatment of different ore types.RÉSUMÉ Le concentrateur de la mine LaRonde a été mis en service en 1988 et a commencé à traiter le minerai du puits Penna en 2000. La capacité du concentrateur a augmenté afin de permettre le traitement de 7 500 tonnes de minerai par jour, capacité qui est retombée à 6 000 tonnes par jour (tpj) depuis le début de l’extension en profondeur de la mine. Ce procédé permet de récupérer de l’or, de l’argent et des métaux communs. En 2008, l’usine de traitement Goldex a commencé à transporter par camion du concentré de pyrite et d’or vers une usine de traitement alimentant en pulpe le concentrateur de LaRonde, augmentant ainsi la production d’or de 40 000 onces. En 2009, les installations de traitement du minerai à haute teneur de Lapa ont été annexées à l’usine de traitement de LaRonde, augmentant la production d’or de 120 000 onces. Cet article passe en revue les considérations métallurgiques liées au traitement de différents types de minerai.INTRODUCTIONThe LaRonde metallurgical plant in the Abitibi region of Quebec, Canada, evolved into a mature milling site following expansions in 2000–2003, thanks to improved processes, manpower, and water treatment capabilities that better accommodate the complex constituents of the LaRonde ore. The ore requires a sequence of grinding, copper- lead and zinc flotation, and precious metals leaching, ending with a carbon-in-pulp (CIP) gold recovery. A portion (35%) of the tailings is sent back underground as paste backfill after being treated with the SO2-air cyanide destruction process. The tailings area has a dedicated cyanide destruction and metal precipitation area through which the used water passes before returning as recycled water. A biological water treatment plant was built in 2004 to address water toxicity in the final effluent. The water toxicity was the result of the high sulfide content of the LaRonde ore (from thiocyanate or stable cyanide species buildup) and the use of 90% recirculated water in the mill. The water treatment plant uses bacteria to transform thiocyanate into nitrates and precipitate phosphorus from the water before it is discharged into the environment."

Jan 1, 2017

By D. Yu, T. A. Utigard, M. Barati

"Sulfation roasting of nickel concentrate to generate water-soluble metal sulfates was investigated as an alternative process to smelting for the recovery of valuable metals. The kinetics of dissolution of various species of the calcine in three leachants was studied; hot water, dilute HCl, and concentrated HCl. The results indicated that dissolution of sulfates by hot water at 90 ºC is achieved within 30 minutes. In order to increase the recovery of the valuable metals, acid leaching is necessary due to the existence of ferrite in the calcine.INTRODUCTIONInvestigations on the sulfation roasting of nickeliferous sulfide ores or concentrates were mainly carried out in 1950’s to 1990’s to generate water soluble non-ferrous metal sulfates followed by metal recovery by leaching (Stephens, 1953; Thornhill, 1954, 1961; Fletcher and Shelef, 1964a, 1964b; Fletcher and Hester, 1964; Frankiewicz, 1977; Norrgran, 1983). Commercialization of the sulfation roasting process was only performed by Falconbridge Ltd. (Thornhill, 1961; Boldt, 1967), which employed a sulfation roast process on nickeliferous pyrrhotite at 680 oC where Ni, Cu, and Co were leached and Fe2O3 was produced for the iron industry. In 1965, 118,342 tons of pyrrhotite was processed, however because of the huge SO2 emissions (no acid plant) relative to the nickel production and the poor economics, this plant was shut down.Nickel production from sulfide ores via pyrometallurgical means, especially the electric furnace smelting process, is a major emitter of SO2 to the environment and a big energy consumer (Warner, Diaz, Dalvi, Mackey, Tarasov and Jones, 2007). Nowadays, due to the more stringent environmental regulations as well as the need to reduce energy consumption, metal production by sulfation roasting is gaining more attention as an alternative process to smelting. The main focus of this paper is to investigate the extent and rate of leaching of valuable metals from the sulfation roasted nickel calcine, aiming to maximize the metal recovery and minimize the dissolution of iron species."

Jan 1, 2012

By G. Scott Zimmer

Mine planning at Cassiar consists of an annual cycle of projection, control, evaluation and revision following completion of annual diamond drilling during the summer months . The inherent difficulty in evaluating fibre grade and distribution, combined with a high-wall phase or push-back mining system, requires continuous modification to designs and schedules based on a cumulative evaluation of equipment performance and prediction versus production. To expedite the planning sequence, a mini-computer system has been introduced which allows emphasis to be placed on optimizing designs, exempting personnel from manual calculations and tabulations.

Jan 1, 1978

By N. A. Warner

Virtually zero gas emission smelting is promoted as a means for securing environmental advantages and the general public’s acceptance. Concerns about climate change will increasingly make it more difficult for new primary metals projects to come to fruition unless greenhouse gas emissions are decreased. Assuming a sustainable market for sulphuric acid is not locally available, the next best option is high temperature reaction of strong SO2 with limestone or dolomite. This is followed by CO2 liquefaction and disposal either underground or in the deep ocean. The Voisey’s Bay nickel project is cited as an example where appropriate location of a new smelter close to large dolomite or limestone deposits would lead to a virtually zero gas emission operation. Most of the electrical energy required for producing technically pure oxygen and for liquefying CO2 and transporting it to disposal can be derived from smelting a bulk sulphide concentrate and then reacting SO2 at high temperature. Provided the smelter gases are properly cleaned before sulphur fixation, the sulphated stone should be uncontaminated and environmentally benign and possibly of use in the building and construction industry.

Jan 1, 1999

By Arthur Notman

Since addressing the Institute a year ago on The Future of the Copper Industry (l), many things have happened, most of them bad. It has been a hard year for profits and prophets. It was, therefore, with consider-able perturbation that I accepted the gracious invitation of your Committee to reappear. On reviewing my remarks of a year ago, I. have wondered whether, under pressure of more important matters, the Committee had neglected to make a note of them, or whether they felt that further explanations from me were in order. In either event, I am glad that I am here and welcome the opportunity to make any contribution I can to a clearer understanding of the problems of copper to those concerned. The English-speaking nations own 80 per cent of the present world-production of the metal. Col. P. E. Barbour, Secretary of the Mining and Metallurgical Society of America, and I recently completed an estimate of the known world resources of copper. We placed the figure, in round numbers, at 100,000,000 tons of metal. Of this amount, about one-third lies in the United States, one-third in the British Empire, and one-third in South America; and all but 4 per cent of this is owned by British Empire and United States capital. Our figures do not include any estimates for Russia, Japan, or Europe, on which there are no available data. It is true, consequently, that the British Empire and the United States are the ones concerned. It seems to me to be a matter of great importance to the world at large, and of even greater importance to those nations themselves, that the known sources of supply of this metal, so essential both in peace and war, rest so strongly in their hands. I cannot believe that in the long run they will neglect their responsibilities in the wise administration of these resources.

Jan 1, 1932