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By E. Roman, M. Brissette

"For its end of life, Kemess Mine processed its difficult-to-treat hypogene ore from the east pit, which is a lower grade copper and higher pyrite content gold ore. Metallurgical testwork showed that improvement was possible with finer grinding. In July 2010, small grinding media were introduced into the regrind mill resulting to a nearly 50% decrease of the power draw with a finer grind, an increase of 1.1% in the final copper grade, an increase of 1.2% in copper and 2.9% in gold recoveries at the cleaners. The overall recoveries of copper and gold increased by 0.6% and 1.3% respectively.INTRODUCTION Kemess Mine was located at 430 km North West of Prince George in North Central British Colombia. Its production started in May 1998 by Royal Oak Mines and was acquired by Northgate Exploration in 2000. Kemess reached its end of life production with its last of production on March 9th, 2011. The concentrator nominal capacity was 56,000 TPD consisting of a primary gyratory crusher feeding two identical conventional SAB circuits totalizing 35,840 kW available for grinding. Rougher flotation consists of four parallel rows of eight 130 m³ tank cells to produce a concentrate of 2% Cu and 6 gr/t Au which was pumped to a 5 m x 10.8 m regrind ball mill. The regrind installed power was 4,480 kW to generate a final grind of 80% passing 40 microns. This product fed the two stage cleaner flotation circuit, first stage being two parallel rows conventional 17 m³ Denver cells and second stage, two 3.3 m x 11.0 m flotation columns in series, designed and constructed by Kemess, to produce a 22% copper concentrate grade. The cleaner flotation middlings were returned back to the regrind mill (Froehling, Mohns, Roman & Grady, 2005; Froehling, Mohns, Rajwani & Fullam, 2007). The large copper-gold porphyry deposit was composed of 15% of oxidized supergene and leach cap ore and 85% of hypogene ore having three major alteration zones, mainly characterized by their sulphur/sulphide content. Chalcopyrite is the main copper mineral species with minor bornite. Gold was mainly present as free gold or electrum. The first alteration zone consisted of a phyllic alteration characterized by moderate and intense sericite alteration which had the highest mill throughput and twice the mine grade when in contact with the supergene horizon. The second zone consisted of a potassic alteration characterized by more competent groundmass and moderate to intense quartz stockwork which had a slightly lower mill throughput. Finally, a third alteration found beneath and on the east side of the deposit having almost no quartz stockwork and hardened groundmass, sulphide content is two to four times more. This zone had the lower mill throughput with significant drop in the mine average gold and copper grade. Through its mine life, the average life of mine copper head grade was 0.21% Cu and 0.64 gr/t Au. Head grades began to decrease from 2008 to be substantially lower in 2011 as shown in Table 1."

Jan 1, 2012

By M. P. Amsden

"Ecstall Mining is a wholly-owned subsidiary of Texas Gulf Sulphur at Timmins, Ontario. The mill tonnage is 10,000 tons per day of two different ores, a copper zinc ore and a silver lead zinc ore, producing about 2400 tons of concentrates per day. These are as a copper concentrate, a high silver zinc concentrate, a low silver zinc concentrate and a silver-lead concentrate. For flotation recovery a very fine grind is required, about 80% minus 325 mesh and the concentrates produced are 40% minus 10 microns.The thickened concentrates are pumped to the filter floor for filtering and drying. The filtering and drying section is separated from the flotation section by a wall and is controlled from a dryer control room by one operator.Two operating panels are located in this control room. One contains stop-start controls for the thickeners, filter motors and vacuum pump motors, and stop-start controls for dryer feed conveyors and dryer product conveyors to concentrate load-out bins, as well as ammeters for conveyor drive motors. Dryer throughput is regulated by Merrick Type L weightometers located on the dryer discharge conveyors and recorded on tons per hour strip charts.The second panel contains the temperature strip charts, furnace drive ammeters, scrubber and exhaust gas controls, burner controls and panel alarms for the four dryers.Filtered concentrates are dried in Nichols-Herreshoff, multiple hearth, dryers consisting of nine hearths (zinc) and seven hearths (copper and lead). There are two dryers for handling zinc concentrates and one each for copper and lead concentrates. The dryers are heated by burning natural gas. Each zinc dryer handles 1,000 t.p.d. and the copper and lead dryers 750 t.p.d. each.Multiple hearth dryers are unusual in the base metal mining industry and the reasons for selecting them in preference to rotary dryers are as follows:1) The concentrates could only be filtered to 15 to 17 percent moisture. These sloppy filter cakes would be extremely difficult to handle in rotary dryers."

Jan 1, 1972

By John C. Wilmot, Robert E. Brewer, Royce J. Smith

In March 2003, Phelps Dodge started up an innovative pressure leach facility for processing copper concentrates at the Bagdad mine in Arizona. This paper describes the development of the concentrate leaching plant at Bagdad and the operational results from start up to present. Optimization efforts and an approach to mineralogical modeling of the concentrate to calculate oxygen utilization are also presented.

Jan 1, 2004

By Donald J. Farrish

"Mr. Chairman and fellow CMP members, most of these remarks will be made with particular reference to copper concentrate but the basics apply generally to other metal concentrates as well.For very good reasons, using copper as an example, smelting capacity usually is located either close to mine production or close to areas of high copper consumption. The mine producer can add on smelting capacity to insure that the copper in his concentrate can be processed into a marketable form under more or less controlled conditions including costs. On the other hand, the consumer wishing to assure a better supply of copper likewise can build smelting capacity and offer treatment charges attractive enough to discourage mines from investing in their own facilities. In this regard, freight is an important factor. Bulk shipments from the heart of Africa with a large overland component are uneconomic whereas concentrate movements from Australia or South America compare favourably with smaller metal shipments.A mine project which incorporates smelting capacity, will often, through the presence of this capacity, encourage active exploration and development of additional concentrate production in the vicinity. The usual result is that new mines within reasonable distance of the smelter will be able to avoid the capital required to build their own smelting and refining facilities and that the existing facilities will expand to appreciate economies of scale."

Jan 1, 1978

By H. McSorley

"I note that many of you are involved in the production of zinc, lead and copper concentrates and metal, which I am the most familiar with among the non-ferrous metals. This afternoon, I will describe briefly the responsibilities of a commercial manager within a mining/metallurgical company, the basic framework of a non-ferrous metals concentrate agreement and lastly, a brief discussion of the copper, zinc and lead concentrate and metal markets.I hope this talk will contribute to a better understanding of the business between all of us and look forward to a discussion after the presentation.First of all, I work for Noranda Sales, which is the marketing and sales agent for Noranda Minerals' three operating units: Noranda Copper, Noranda Zinc and Mining Corporation. In addition, Noranda Sales acts for other mining companies in the marketing of their raw materials and metals. Noranda Sales is responsible for procuring all raw materials for Noranda's metallurgical plants, such as the Copper Group's Forne and Gaspe smelters, as well as the sale of surplus concentrates and by-products and metal products. In addition, Noranda Sales trades metals and concentrates and owns a metal brokerage business, Rudolf Wolff, a founding member of the London Metal Exchange. It does $3 billion of business in 60 countries, exporting some 80% of Noranda Minerals' output to the world.What are the responsibilities of commercial management in resource marketing to the mine and metal producers?Resource marketing and commercial administration involves assistance in establishing exploration priorities, contributing to feasibility studies, pre-production planning, product promotion and realization of income for many properties and metallurgical plants through completion of supply and sale agreements with other companie"

Jan 1, 1988

By S. P. Lowe

Flotation testing of Flin Flon ore was started in the Denver laboratory of Complex Ores Recoveries Co. in March, 1926. There had been a considerable amount of flotation testing previously which had shown possibilities of success, and it was felt that, with the increased knowledge of flotation and the comparatively new reagents then available, flotation held out the best prospects for a successful commercial treatment of this ore. There remained available for this experimental work a small amount of the rejects from a thorough sampling of the mine and some ore from the mine dump.

Jan 1, 1930

By The Staff

"IntroductionThe published information concerning treatment of uranium ores has been very limited as far as Canadian ores are concerned. Such information has dealt mainly with refining processes for concentrates or rich ores, designed to recover radium rather than uranium; these methods could not be economically applied to low-grade ores.The purpose of this paper is to describe treatment possibilities for some of the .ores that have been treated at the Mines Branch, and .to show how the character of these ores influences methods and results.What is a Uranium Ore?Prospecting for uranium has been extremely active during the past two years and a great many occurrences of radioactive minerals have been recorded. Such prospecting has been based to a large extent on the use of the Geiger counter in the fie1d. This equipment is an invaluable aid when the results are properly interpreted.Most definitely, indications of high radioactivity do not always prove the presence of a valuable orebody. First we have to determine:(1) Is the radioactivity due to uranium or to thorium. There is no immediate market for thorium.(2) Can the uranium in the ore be economically recovered.Chemical analysis is the most exact method of determining uranium content, but a fair estimate of the uranium, and also of the thorium, content can be made from the difference in gamma and beta activity. The Mines Branch guards against misinterpretation by determining both beta and gamma activities and, if more than a minor amount of thorium is indicated, then a Chemical analysis is made."

Jan 1, 1950

By C. S. Parsons

Introductory The steady advance in the price of lead and zinc in the metal markets of the world during the past few years has resulted in an active search for new deposits of these metals, and to the re-examination of known properties that are now idle. There are a number of deposits of these metals in eastern Canada, the best known of which are the Tetreault mine at Notre Dame des Anges, Que.; the Reader mine on Calumet island, Que.; the Stirling property in Cape Breton, and the Federal mine in Gaspe district, Que. . The author has run concentration tests on the ores from the first three mentioned properties. The ores from Notre Dame des Anges and Calumet island presented problems in concentration which were not successfully solved until the past year. Although considerable experimental work has been done by the Ore Testing Laboratories on the ore from the Stirling mine we have not been successful in developing a satisfactory method of treatment. Character and Types of Ores Metallurgically the lead-zinc ores of eastern Canada may be classified into three distinct types as follows: First: - Ore in which the sulphide minerals are fairly coarsely crystalline and can be freed by crushing to 40 or 60 mesh. The zinc blend has a high iron content (not marmatite) and gives a dark brown colour on grinding. The ores of Notre Dame des Anges and Calumet island, Que., may be cited as examples.

Jan 1, 1925

By R. Biss

"Niobium or columbium, as usually called in North America is becoming a more and more important metal in the industrial world because of its attractive properties.Eventhough discovered in the early nineteenth century, it was not until the 1930's that its use became more widespread. The discovery of large commercial deposits in the late 1950's and the demand of industry for steel with high strength and toughness further promoted its use. To assure its adequate supply new or-e processinr technologies had to be developed. So, beside the traditional gravity concentration, the flotation process was employed for the partial upgrading of pyrochlore concentrate at S8ve (Norway) plant in 1953. The flotation process was equally used at St-Lawrence Columbium plant in the province of Quebec, Canada. The new plants at Araxa and Catalao in Brazil and at St-Honore, Canada, which supply almost of all niobium used today in the non-Communist world, also adopted the flotation process. The processes using long chain aliphatic rnonoarnines, diamines or sulfonates as collectors proved to be difficult especially on weathered types of ores or on those having a substantial content of silicate gangue minerals. They almost completely failed in case of alkaline intrusive rocks as syenites, nepheline syenite, ijolites and pyroxenites, composed almost entirely of silicate minerals. A lot of effort was devoted all around the world on research of new, more efficient flotation processes. So in 1982, Les Services T.M.G. Inc. (Niobec), sole producer of pyrochlore concentrate in North America, developed the direct pyrochlore flotation process from carbonatites. In 1983, at about the same time, the Quebec Department of Natural Resources Laboratories and Les Services T.M.G. Inc. announced a successful recovery of niobium Minera1s from a low grade nenheline syenite ore."

Jan 1, 1984

By G. F. Liu, S. Owada

Platinum Group Metals (PGMs), Pt, Pd, Rh, have been widely used as a three-way catalyst to clean discharged gas from automobiles and therefore a considerable amount of the spent catalysts is generated annually. This paper proposes a novel concentration technology of PGMs by utilizing the double-deck structure of PGM bearing alumina-ceria and cordierite phases. The applied technologies are a combination of heating-quenching, selective grinding and screening for separating alumina-ceria phase from cordierite. Temperature change as a function of quenching time and the thermal stresses applied to both phases were simulated and calculated by FEM, and it was clarified the mechanism of micro-cracks generation at the phase boundary and micro-cracks in alumina-ceria phase, which indicated that separation of alumina-ceria phase from cordierite and selective breakage of alumina-ceria phase could be achieved in the subsequent selective grinding with an attritor. This process could concentrate 46 wt% of alumina-ceria phase into fine fractions with 86 % recovery efficiency. The remaining alumina-ceria phase can be further recovered by applying flotation and so on.

Jan 1, 2015

By D. Raicevic

Interest has recently been revived in the recovery of tantalum from the Bernie Lake pegmatite deposit. A gravity concentration process was developed to give satisfactory recovery and concentrate grade. The application of high-intensity magnetic separation was also stud1ed. A pilot-plant investigation that confirmed the laboratory testing and provided a commercial-grade concentrate 1s described.

Jan 1, 1968

By G. W. Neumann, J. R. Schnarr

The lead-zinc-copper-silver ores mined by Brunswick Mining and Smelting Corporation Limited at their No. 12 underground mine and No. 6 open-pit operation, and treated by distinct concentration processes in separate plants, present difficult metallurgical problems because of the extremely fine dissemination of the valuable minerals with pyrite and pyrrhotite. The problem of concentration is further complicated, in the No. 12 ore, by the presence of a varying content of graphitic carbon. This paper describes the milling of No. 12 ore and the production of copper, lead and zinc concentrates by differential flotation.

Jan 1, 1971

By D. Linzey

"History of Whitehorse Copper BeltThe first discovery of copper on the Whitehorse Copper Belt is reported to have been made by miners on their way to the Klondike in 1897. By 1899 the district had been well prospected and many of the presently known deposits had been staked.The first shipment of ore was from the Copper King property in 1900. This consisted of 9 tons of hand picked ore grading 46.4% copper. It was not until the period between 1912 and 1917, the production years of the Pueblo Mine, that significant ore shipments were made. Total production was 140,000 tons at 3.5% copper. An underground disaster killed six men and closed the mine in March 1917.Although the general area was dormant until after World War II, by 1947 geological mapping, magnetic surveys and diamond drilling had been done on the important showings. In 1954 Mr. Aubrey Simmonds directed the formation of Imperial Mines and Metals, which acquired by option and staking a large part of the Whitehorse Copper Belt. In 1957 Mr. Arnold Pitt reorganized the company as New Imperial Mines. With financing from Sumitomo and Toronto-Dominion Bank, a mill was built and production was started from the Little chief orebody by open pit in 1967."

Jan 1, 1977

By Martin Nevens

"In 1998, the Iron Ore Company of Canada initiated an aggressive program to improve the performance of its Carol Lake Concentrator located in Labrador City, Newfoundland. This program was termed the Concentrator Upgrade Program. The Concentrator Upgrade Program was a group of initiatives developed with the common goal of improving the overall process and operations of the IOCC Carol Lake Concentrator. The main goal of the program was to increase the annual production capacity of the concentrator from 18.0 million tomes to 21.6 million tomes. This gain in capacity was to be done mainly through improvements in process iron recovery. The target iron recovery value was 80+% versus a historical value of 70%. This improvement in iron recovery would translate to a natural weight recovery improvement from 44% to 50%.The Concentrator Upgrade Program provided the first opportunity in 30 years to make fimdamental changes to the concentrator flowsheet. To accomplish this, several pilot plants were built to evaluate new circuits. AAer 2 years, a new flowsheet was selected for the primary gravity separation circuit and the magnetite circuit. The centrepiece of the new flowsheet was the introduction of Hindered Settling Separators to the metallurgical process.The Concentrator Upgrade Program has since proceeded into detailed engineering and, as of February 2001, construction. The first one of IOCC’s 3 primary AG Mills (Mill 11) has been converted to the new flowsheet at the time of writing and is in the throes of commissioning. This paper will review the flowsheet development program in the pilot plant for the gravity separation circuit and examine the overall benefits to the operation of the IOCC Carol Lake Concentrator."

Jan 1, 2002

By Alessandro Navarra, Kristian Waters

Mineral concentrators are designed from preliminary geological data, and are therefore subject to geological uncertainty. This uncertainty has a demonstrable impact on the mining lifecycle, and has motivated stochastic strategic mine planning algorithms. The current paper describes how these algorithms may be extended to consider mineral processing operations in conjunction with open-pit mining operations. In particular, the paper describes an effective way to incorporate variable concentrator feed grade into these algorithms, which is the first step toward more elaborate representations of mineral concentrators. The resulting framework will be able to connect geological data to alternate configurations of the downstream resources, hence comparing the benefit of each configuration, and the corresponding capital investments. Sample computations are presented, comparing the NPV and utilization for several different mineral processing capacities.

Jan 1, 2015

By Denis Labrie

Résumé Cent soixante (160) câbles d'ancrage ont été installés au toit de la rampe à la Mine-laboratoire de CANMET à Val-d'Or, Qué bec, Canada, pour prévenir toute dégradation suite à l'élargissement de la voie de roulage dans un secteur tournant à 180 degrés, communément appelé Virage Santa Barbara. Le roc à cet endroit est de nature bloqueuse et stratifiée, et son épaisseur au toit de la rampe est limitée à environ dix (10) mètres, le tout sous une couche de terrain meuble saturée en permanence. Le soutènement mis en place a été conçu pour former une zone de compression et supporter une strate de roc d?environ quatre (4) mètres d'épaisseur. Les critères de conception et les méthodes d'installation sont présentées. Un contrôle de qualité rigoureux a été effectué au moment de la mise en place du support, notamment en ce qui concerne la mise en tension des câbles eux-mêmes et la qualité du béton utilisé lors de l'injection. Des instruments de mesure seront mis en place sous peu pour dépister tout mouvement éventuel au toit de la rampe. Abstract Design and installation of an active mine ground support using tensioned cables at the Experimental Mine, Val-d?Or, Québec, Canada. One hundred sixty (160) cables were installed at the back of the ramp at the CANMET?s Experimental Mine located in Val-d?Or, Québec, Canada, to prevent any degradation of the ground after the enlargement of the roadway in a sector turning at 180 degrees, usually called Virage Santa Barbara. The nature of the rock mass in this area is blocky and stratified, and its thickness above the ramp does not exceed ten (10) metres. Eight (8) metres of soil, mostly saturated, cover the bedrock on top of the ramp. The ground support was designed to form a compression zone at the back, aimed to carry a strata of rock of around four (4) metres thick. The design criteria and the methods of installation of the ground support are described in the paper. A strict control of the quality of the grout used for injection and the tension placed in the cables was carried out during the installation of the support. Ground monitors will be installed soon, to detect any movement that could take place above the ramp.

May 1, 2001

By Michel Dostie

Un séchoir à vis chauffé par induction électromagnétique a été développé et implanté chez Mines Niobec pour le séchage d?un concentré de niobium. Ce séchoir a permis une réduction des émissions de poussières et des gaz à effet de serre de l?usine. Il offre une grande souplesse de contrôle, une meilleure efficacité énergétique et peut être utilisé pour le séchage de granulats, de poudres ou autres substances habituellement traitées dans un four rotatif ou à l?aide de vis chauffées par un caloporteur. Le principe de fonctionnement du séchoir est simple. Trois inducteurs opérant à la fréquence du réseau électrique assurent le chauffage des parties métalliques du séchoir, dont des vis qui servent à convoyer le matériel. Le contact du matériel avec les parties métalliques chaudes permet le transfert de l?énergie requise pour le séchage. La conception de ce type de séchoir requiert un équilibre adéquat entre les besoins associés au chauffage par induction et ceux liés au transfert de chaleur par contact et au transport du matériel dans le séchoir. Cette première implantation industrielle a nécessité des efforts de développements importants et une collaboration des différents intervenants. Une revue des principes de conception, des difficultés rencontrées et des performances obtenues sera présentée.

May 1, 2007

Conventional waste management practices produce two waste streams for the construction of separate disposal facilities. The design of tailings impoundments is usually controlled by physical stability. Waste rock materials offer high shear strength characteristics for waste dump construction, however the hydraulic properties promote oxidation. The problem of oxidation is significantly reduced for tailings due to a fine texture that augments water saturation. Co-mixing of tailings and waste rock involves the intimate blending of tailings and waste rock to create a new material with superior physical and hydraulic properties. The new material has a low hydraulic conductivity, low compressibility, high water retention capacity and high shear strength. Co-mixed tailings and waste rock restrict oxygen entry and water seepage to minimize acid generation and metal leaching. Co-mixed tailings and waste rock may be used to construct cover systems, internal barriers and seals, confinement structures and full depth waste repository. The results of a laboratory program to characterize the physical and hydraulic properties of Comix tailings and waste rock are presented here. Various ratios of tailings were blended with three distinct waste rock materials. The saturated hydraulic conductivity for the Co-mixed materials was found to vary between 2 x 10-7 m/s and 5 x 10-8 m/s depending on blend ratio, waste rock type and compaction. This paper introduces concepts for the co-disposal of tailings with waste rock and evaluates the hydraulic behaviour of a Co-Mix waste system. The potential benefits of Co-Mix are shown for a typical mine.

Nov 1, 2002

By L. J. Vincze

The high cost of constructing mineral processing plants in remote locations warrants a close examination of the alternatives available for reducing the amount of on-site construction work. Among the alternatives are portable process plants, modular design and barge mounted plants. Each alternative has certain advantages as well as limitations depending upon specific conditions. On the basis of practical experience and engineering analysis, the paper examines the potential benefits to be realized by these techniques and summarizes the conditions required to obtain them. The potential savings indicated by such studies should encourage consideration of innovative design features for new plants located in remote areas.

Jan 1, 1980

By S. Luidold, A. Poscher, H. Antrekowitsch

"The rare earth elements (REE) are nowadays mainly used for permanent magnets, catalysts, hydrogen storage alloys in rechargeable batteries, for glasses, ceramics, and polishing agents. Other important areas of application are phosphors in different types of lamps (fluorescent tubes, energy-saving lamps, etc.). These lamps are often collected and treated at their end of life by disintegration and sorting. However, the obtained fine fractions comprise not only REE-containing phosphors but also small amounts of mercury and are therefore disposed till today in special landfills. Due to the enormous price increase of the rare earths during the last two years, a lot of activities started for extracting these elements from secondary resources such as for example phosphors. All recycling concepts for this task mainly work with hydrometallurgical methods. The large number of different compounds in phosphors with sometimes very different behaviors with respect to their solubility in aqueous phases forms a major challenge to achieve good yields as well as acceptable purities of the produced rare earth concentrates by a process with a reasonable number of operation steps. Therefore, this paper gives at first a brief overview about the compounds, used as phosphors and about existing concepts or investigations. It further describes our own process design and the results, obtained on laboratory scale. INTRODUCTIONThe rare earth elements (REE) have a central position in the industrialised world despite their marginal production volume in comparison to common metals such as aluminium, copper, zinc etc., because they are essential for many applications. They often cannot be substituted without a considerable loss on functionality and quality. This group of metals comprise the lanthanoids (f–block elements, lanthanum–lutetium) as well as scandium and yttrium.The estimated world mine production of REE amounted to 133,000 t rare earth oxide equivalent in 2010, whereat China accounted for 130,000 t or 98 % (Cordier, 2012). The European Union (EU-27) imported 23,013 t in 2008 to cover its demand. The figure 1 shows the fraction of the European member states in terms of the total imports of rare earth compounds from outside the EU-27 (Schüler, Buchert, Liu, Dittrich, & Merz, 2011)."

Jan 1, 2012