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By W. J. D. Stone

"INTRODUCTION Over the past decade, a number of publications have described the advances in High Intensity Wet Magnetic Separation. A number of significant, but small capacity installations were made and are successfully operating. These were followed some three years ago by larger installations treating ilmenite gravity concentrates; at least one machine treating 25 tons per hour of new feed was installed and is successfully operating.However, this still did not result in general acceptance that High Intensity Wet Magnetic Separation could be applied on a large scale. Neither did it dispel the feeling that High Intensity Wet Magnetic Separation was ""expensive"" and hence, confined to small scale – high value applications suchas the cleaning of tin concentrates. In addition, there is the usual reluctance of being the ""guinea pig"" which has resulted in waiting to see ""someone else"" make the first large installation decision. Such a decision and installation has now been made.Therefore, the purpose of this paper is to show that High Intensity Wet Magnetic Separation has been commercially accepted on a large scale and to show its general application to the base metal mineral industry.Examples are confined to a few specifics due to the large volume of preliminary test data that is available. The art has now reached the stage where much of the preliminary work should be taken through to serious evaluation."

Jan 1, 1971

By W. F. James

"The property of Siscoe Gold Mines, Limited, comprises about 1,600 acres, including Siscoe island and adjacent claims under water in Montigny lake, in Dubuisson and Vassan townships, Quebec.For many years the property was reached by way of Harricana river and its chain of lakes from Amos, Quebec, about 45 miles distant. In later years a highway has been built from Noranda east through Val d'Or, about 5 miles distant.Gold was discovered on one of the claims on the north shore of Montigny lake as early as 1911, but these gold discoveries have never been economically important. Several years later gold was discovered on Siscoe island and considerable surface work was carried out. Still later, iscoe Gold Mines, Limited, was formed and carried out further work, some of it through shallow shafts. In 1928, larger scale operations were undertaken and a 100-ton mill was constructed. In the years following, production· was on a larger scale with lower grade, until finally a milling rate of over 1,000 tons a day was attained. Approximately 1,500,000 tons were treated between the end of 1940 and mid-year 1945. At present the milling rate is down to about 200 tons a day and work is confined chiefly to some of the less important veins that have been recently developed.The following is a summary of production up to December 31st, 1946:"

Jan 1, 1954

By J. M. Ortiz, J. Haas, W. Kracht, G. Pamparana

This work explores the effect of ore hardness variability on the design of a solar photovoltaic system with battery storage and grid backup, to operate a semi-autogenous grinding mill (SAG). First, a case of two synthetic ore populations was studied, without any consideration of spatial distribution. The mean and variance of the ore hardness (measured in specific energy consumption) of both populations were subjected to a sensitivity analysis. The operation was evaluated with one and two stockpiles. The latter allows classifying according to ore hardness to adapt the SAG energy consumption to the solar cycle. The results show that using two stockpiles allows achieving a larger autonomy (i.e., fewer energy imports) at lower total costs, especially when the difference of mean hardness between the two populations is large. The difference in variance (between the two populations) has a smaller impact on the design recommendations. Second, a case study was performed considering the spatial distribution of geometallurgical units. Two cases were considered: (a) brownfield, when there is historical information of the actual variability of the ore hardness; and (b) greenfield, when the system design relies mainly on geometallurgical modeling. Brownfield and greenfield planning result in similar sizing recommendations of the solar power plant if precise drill cores are available. In this case, geometallurgical modeling is an effective tool for forecasting the energy demand necessary for designing the power plant. INTRODUCTION Solar energy can help make mining more sustainable (Moreno-Leiva et al., 2017). With falling battery costs, an autonomous solar supply is soon to become an economical alternative in many parts of the world, even in the presence of a larger power grid (Child et al., 2017). Although this, places with high solar radiation such as the Atacama Desert in Chile, nowadays show a large potential of incorporating solar energy as a supply of energy. Many of the Chilean copper mines are in this zone making it interesting to study their compatibility and potential of integrating this renewable source to their operation. The power demand in a copper mineral processing plant is determined by the main power loads in grinding and flotation, with grinding typically the largest power consumer, especially the semi-autogenous grinding (SAG) mills (Wei and Craig, 2009). In Chile, it corresponds on average the 50% of the electrical energy consumption (COCHILCO, 2013). Solar energy production is determined by the irradiance perceived into the solar photovoltaic (PV) panels (which varies through the geographic location) and several other climatic parameters such as the current season, humidity, temperature, altitude, and others (Molina et al., 2017). Also, solar energy is only generated during the sun hours, getting to a maximum generation at a certain peak hour during midday, and finally dropping to zero during the night. This shows a cyclic parabolic profile as shown in Figure 1. Due to the SAG mill operated continuously, the power supply always must be available. During the night, to continue supplying the energy, it is necessary to complement the solar power generation with a battery energy storage system (BESS), which will act as a power backup and a buffer. For the optimal sizing of this PV- BESS system, information of the demand profile is needed (Pamparana et al., 2017). In the case of the SAG mill operation, the resulting demand relates to the ore-hardness for a specific throughput and grind size (Morrell, 2004). Therefore, for a given throughput and target grind size, a harder ore would require more power, and variable hardness results in more variable demand and a subsequent need for larger energy storage (Bueno et al., 2015). Due to the ore-hardness variability and the operation of the mill, the power demand profile in inherently variable.

Jan 1, 2019

By Ken Musgrave

"What Most Effective Management Does?It must satisfy the demands, of three groups of people: owners, employees and the public.OwnersOwners want profitable operations that will pay them a return on their investment, plus operations managed for long life. Many owners are also concerned with employee's well being and their company's public image.EmployeesJob security and a good income are probably still the most important demands, however, as time goes by, employees are also demanding more involvement in safety issues, working conditions, and even how work is done.The PublicThe public requires acceptable environmental standards, as well as enjoying the prosperity supplied by a successful operation.How are Mines Managed?Most mines are managed very traditionally. The basic credo is that the managers make the decisions, and the hourly, and junior salaried employees do what they are told. Clearly this is the extreme case, epitomized by the long service shift boss who might say ""It took twenty-years to become a shift boss, and no miner is going to tell me what to do"" .There are some exceptions, two notable ones being Campbell-Chibougamau, and T.G.S. (now Kidd Creek Mines) which, in very different circumstances, decided on a more participative style.Campbell-Chibougamau, having closed down due to unprofitable operations, reopened, using a team structure with working leaders, and a system for sharing gains against cost targets with employees. Although the system has some problems, and development miners are bonused conventionally, this has been a basically successful program.Texasgulf Sulphur, a company with a history of non-union operations, and a participative management style, made a corporate decision to operate their Kidd Creek Mine in the same way. The orebody was rich enough to allow them the luxury to do this, but they have never had a strike, so perhaps they have more than saved the cost of the benefits and salaries they needed to pay. They also reward employees with a stock distribution scheme based on service and earnings."

Jan 1, 1985

By G. Vibert Douglas

It has long been recognized that there are considerable difficulties connected with the physical and chemical explanation of shoots of ore. The literature of Mining Geology has frequent references to this subject; but the reasons given for the actual location of primary ore-shoots have been very tentative. In practice, the geologist or miner depends to a great extent on sampling and assaying to determine the boundaries of profitable ore within the mineralized zone. An ore-shoot is a portion of a mineralized zone which has a sufficient concentration of valuable minerals to make it ore. Ore deposits have been classified according to many schemes. There are classifications based on morphology and on genesis. However, it is also possible to classify hypo-gene hydrothermal ore-bodies in terms of ore-shoots or vice versa. A.-Ore-deposits in which the whole of the mineralized zone is ore, which is the same as saying that the ore-shoot extends throughout the mineralized zone. An example of this type of deposit would be the pyritic mineralization of Rio Tinto. B.-The second type would comprise those deposits in which the ore-shoots bear some relation to the geological structure of the area: all deposits in which 'bonanzas' occur in folds in the zone, at the intersection of veins along certain fault (or joint) features and other such controls. There are a great many examples of this type: (a) The Rhodesian copper lodes, where Bancroft and Gray have pointed out the association of the shoots of ore with drag folds. (b) A similar association has been pointed out by Faribault for some of the gold veins of Nova Scotia, e.g., Mount Uniacke. (c) The great bonanza of the Comstock lode in Nevada. C.-Deposits in which the localization of ore has been effected by the chemical character of the wall-rock. Examples of this type are the Fahlbands of Scandinavia, and the 'indicator' deposits of Ballarat, Australia. D.-Lastly, deposits in which there is apparently no structural and no chemical control.

Jan 1, 1934

By F. G. Smith

Abstract Laboratory methods are now in use whereby the temperature and pressure during the crystallization of hydrothermal minerals can be determined. The techniques include the use of the decrepitation method of studying liquid inclusions, and electrical measurements of pyrite. The determinations are sufficiently accurate that the data can be used in solving a variety of ore deposition problems. Within the last year, several new laboratory techniques have been developed in the Geochemical Laboratory of the Department of Geological Sciences, University of Toronto. The results of several tests of ore by these methods have proved to be useful in treating some problems which previously were considered unsolvable. It is now possible to determine the temperature of deposition of most of the minerals in a hydrothermal ore deposit, also the depth below the surface during deposition. Measurements can also be made of the reopening history of a complex ore. The temperature-pressure determinations depend upon the fact that minerals deposited from a hydrothermal solution always trap a small amount of the solution at the time of crystallization. The solution, being predominantly composed of water, has a density which depends upon the temperature and the pressure prevailing during crystallization. After ore deposition is complete, erosion and isostatic uplift finally exhumes the vein. During this slow fall in temperature and pressure, the solution contracts and a gas bubble appears. If the trapped solution in the mineral is examined, the gas-liquid ratio records the density of the solution at the time the mineral was deposited (except for a slight change in the volume of the mineral). The thermal expansion and compressibility of water and water solutions are known to a sufficient degree that, if the gas /liquid ratio can be determined, the temperature-pressure relations during deposition can be calculated.

Jan 1, 1949

By A. Yousefpour, M. Hojjati, G. Chouinard

In recent years, high performance thermoplastic composites such as PEEK and PEKK have been developed for aerospace applications. These materials offer, among the other properties, high toughness and damage tolerances. These are semi-crystalline materials and their processing can lead to different crystallinity that in turn have some impact on the final properties. The effect of cooling rate on degree of crystallinity of PEEK is studied to identify the processing window for manufacturing. Samples were heated at the constant heating rate of 20°C/min up to 375°C (above melting point) and held for 10 minute. The enthalpy of the crystallization was measured at different constant cooling rates of 0.5, 1, 2, 5, 10, 20, 30, and 40°C/min. After cooling, the samples were heated at constant heating rate of 2°C/min using modulated DSC. At temperature between 90°C to 375°C, two endotherm peaks were observed. Results suggest that endotherm peaks are related to a melting and recrystallization phenomenon of one crystal morphology. However, the second endotherm peak could be associated with another crystal structure or morphology.

Jan 1, 2006

By Finch. J. A., C. Perez, J. M. Ortiz, G. Cortes, A. B. Yañiez, F. Coddou, P. Morales, H. Elgueta

A campaign to perform characterization tests in a TankCell®-300 flotation cell installed at Chuquicamata Codelco's concentrator was conducted. The campaign included integrated gas dispersion measurements (gas velocity radial mapping and single point gas holdup and bubble size) and determination of frother concentration. Cell streams were sampled to assess metallurgical performance at the same time. The experimental program was designed to establish the bubble surface area flux operating range and its effect on performance, and the effect of using longer residence times and of a device designed to enhance mixing in the collection zone (FlowBooster(TM)). The gas dispersion results and their relationship to metallurgical performance are discussed.

Jan 1, 2009

By Evans B. Mayo

ABSTRACT Orange Footwall 'sill' is locally concordant locally discordant, with the structure of its sedimentary walls. The sediments were folded in two directions. Folds, following both these directions, are preserved in the concordant portion of the 'sill'. It seems, therefore, that the porphyry has replaced the sediments, thus preserving within itself their structure. During replacement, the nascent porphyry may have been much weaker than its walls. Accordingly, under directed pressure, the porphyry could have flowed locally, disarranging the replaced structures within it and developing a flow structure discordant with the folds in the sediments. Some such action may account for the discordant parts of the 'sill'. INTRODUCTION The senior author has seen certain granitoid massifs that have an internal structure vastly different from, and discordant with, the structures in their wall rocks. It seems that? such massifs have moved independently of their surroundings. Yet, a structure section elsewhere in the same mountain range may reveal granitic rocks with internal structures that appear to continue the structure of the invaded rocks. In such a case, it is at least thinkable that the granite has replaced the older sediments or volcanic rocks. In February, 1950, the writers mapped, on 15 level of the Nickel Plate mine, near Hedley, B.C., a diorite or gabbro porphyry 'sill' that, in one cross-cut (1503), appeared to be quite concordant with the wall-rock structures, whereas in another cross-cut ( 1500) about 100 feet to the south, the same porphyry was discordant (see Figure 1).

Jan 1, 1951

By H. H. Gardner

Introduction The Greenhill mine of West Canadian Collieries, Limited, is on the Alberta side of the Crowsnest pass, twelve miles from the Alberta British Columbia boundary-line. Here, five coal seams of Lower Cretaceous age are found in the Kootenay formation. They outcrop on the north and south slopes of the valley, with strike approximately N.30°W., paralleling the main range of the Rocky mountains, and dip about 40 deg. westward. Of the five seams, only two, designated No. 1 and No. 2, have been worked to date. On the West Canadian Collieries property, No. 1 seam ranges in thickness from thirty feet to nil. Generally, it has a hard, strong conglomerate roof. No. 2 seam is separated from No. 1 by forty-five feet of shales and sandstones. It has a thickness of eight to thirty feet.

Jan 1, 1947

By Stanley Davidson

"The ore deposit mined by Falconbridge Nickel Mines, Limited, is one of the numerous nickel-copper sulphide bodies marginal to the large oystershaped mass of differentiated norite in the Sudbury district, famous as the world's most important nickel producing field. The unique character of the ore deposits of the district has resulted in its intensive geological study over a period of more than 50 years. The results of these studies have given rise to a voluminous geological literature and to a great deal of controversy as to the genesis of the ores. This description of the structural geology at the Falconbridge mine is presented in the hope that it may form a small part of the chain of evidence leading to a reasonably satisfactory explanation of the ore genesis.The mine, named after Falconbridge township in which the deposit occurs, lies along the southeast margin of the norite mass, which, however, is h::re concealed beneath a deep mantle of glacial sands and gravels averaging over 100 feet in thickness. As a consequence, the deposit was not discovered by the early prospectors, and it was not until 1916-17 that E. J. Longyear, of Minneapolis, located the ore by drilling(ll). The discovery was foreshadowed in 1899 by the work of Thomas A. Edison, who found indications of the deposit by what is believed to have been a combination of magnetic and electrical geophysical surveys. He sank a prospect shaft over what has to date proved to be the largest and richest ore section in the mine. A wet quicksand layer at the rock surface proved impenetrable, however, and the 'Edison' shaft never reached bed-rock.The Falconbridge property was acquired by the Lindsley interests in 1928, and ore output, since its inception in 1929, has gradually risen from a modest beginning to the present 2,000 tons and more daily. Total production in this period is 7,500,000 tons of ore averaging 1.72 per cent nickel and 0.89 per cent copper, together with a small but valuable content of precious metals, principally of the platinum group."

Jan 1, 1954

By David Dreisinger

Arsenic occurs in nature in association with many valuable metals including copper, nickel, cobalt, gold and platinum group metals. The recovery of these valuable metals is of course complicated by the need to extract and stabilize arsenic in a form suitable for disposal. In this paper, a review of some recent developments related to hydrometallurgical treatment of arsenic bearing materials is provided. The key aspects of metal dissolution, arsenic stabilization and disposal are discussed.

Jan 1, 2014

By B. S. W. Buffam

"The property of Moneta Porcupine Mines, Limited, consists of a group of eight claims in Tisdale township, Ontario. It includes part of the townsite of the town of Timmins, and adjoins the west boundaries of the Hollin_ger Consolidated and Mace properties. The Moneta property was first staked in 1909, about a year after the first discovery of gold in the Porcupine camp. In 1910 the Moneta Company was incorporated and some preliminary exploratory work performed by Nova Scotia Mines of Cobalt. In 1912 English interests advanced $90,000 for diamond drilling and underground work. One drill hole gave high assays, but apparently the records were poorly kept or the cores were interchanged. As a consequence, when underground exploration was undertaken in 1923 it was directed south rather than west and no ore was found . In 1924 about 5,000 feet of diamond drilling was done in the southern part of the property, but without intersecting ore.In 1931 W. E. Segsworth assumed the direction of the property. Diamond drilling commenced on August 18, 1936. The first hole intersected 9.9 feet of ore averaging 1.23 oz. gold a ton. Underground work was started early in 1937. A mill was erected in the autumn and the first gold brick was poured January 29, 1938.The Moneta mill began operation on January 2, 1938, and the following table gives a summary of the production to June 30, 1943, when the mill was closed."

Jan 1, 1954

By C. Chapman, P. Cowx

"INTRODUCTIONTetronics Research and Development Co. Limited has installed several plasma torches for steel heating in continuous caster tundishes. An extensive demonstration program on a 14 tonne tundish reported the following advantages of plasma heating.• close control of steel temperature to ± 5°C;• a reduction of the furnace tapping temperature of up to 20ºC, leading to savings in energy and refractories costs ;• improvement in steel quality, to produce a slab product with an equi-axed crystal structure and a reduced number of large sub-surface slag inclusions;• the virtual elimination of oxygen pickup in the tundish; and• the capability of making ferroalloy trim additions to the tundish to permit a change of steel grade during casting, greatly decreasing inventory costs.The Need for Tundish HeatingIn the continuous casting of steel, the function of the tundish is to transfer the molten metal between the ladle to one or more continuously fed casting moulds. Figure I shows a typical temperature profile of molten steel in the tundish over the first cast cycle. It is observed that a rapid drop in temperature occurs both at the start of the cast, due to the tundish refractories absorbing heat, and also during ladle changeover. In addition, as a result of thermal losses through the ladle sidewalls, there is a gradual decline in the bulk steel temperature over the entire heat cycle. Consequently, in normal tundish operation, it is necessary to cast with a high superheat (25°C to 30°C + above steel liquidus temperature) in order to prevent freeze-up of the strand. Problems of high temperature variation and the potential of the steel solidifying in the tundish are greater for small caster units of low thermal mass . A high steel superheat increases the steelmaking vessel process time and refractory wear and prevents the formation of a uniform equi-axed solidification structure in the cast steel, resulting in centre line segregation and porosity. The large drop in the casting temperature that occurs during unsteady state operation causes an increase in the number of sub-surface inclusions, reducing the value of the product. Accordingly, plasma heating may be employed to maintain the molten steel at an optimum temperature to produce a slab of consistent quality."

Jan 1, 1989

By C. B. Ndimande, C. Ntsele, M. Lisso, L. Arlow

"In the processing of UG2 platinum ore, stirred milling technologies are dominating regrind applications that require grinding the particles to P80s’ in the region of 45 µm. For this application stirred mills are 30–40% more energy efficient and require a smaller foot print compared to traditional tumbling mills. In this work a study was carried out using a batch pin mill and three scales of Stirred Media Detritors. A laboratory scale pin mill, a pilot scale Stirred Media Detritor with an installed power of 18.5 KW and two industrial scale Stirred Media Detritors in continuous operation, with an installed power of 355 KW and 1,100 KW were used. The industrial scale SMDs were in the secondary grinding section of a mill floatmill float (MF2) UG2 processing plants. The tests were focused on assessing the effect of feed rate and percent solids on power consumption and product fineness at lab scale, floatation response of the SMD product at pilot scale and on an industrial scale, the effect of feed rate on energy consumption and product fineness. The measurements obtained were feed flow rates, mill power and from the samples cut, particle size distribution of both feed and product. Specific energy was observed to increase with increasing percent solids over the 30wt% to 80wt% studied. Floatation response tests of the pilot scale SMD products show improvement in grade. Specific energy and reduction rations are observed to decrease with an increase in feed rate.INTRODUCTIONThe purpose of comminution in most mineral processing applications is to liberate the valuable minerals from gangue so that they can be recovered in subsequent separation stages. Most precious and base metal plants treat low grade fine-grained ores which require a higher degree of size reduction to yield the necessary degree of liberation (Partyka & Yan, 2007). Many authors have shown that the relationship between product size and grinding energy consumption is exponential, the finer the product from the comminution device, the higher the energy consumption (Gao & Weller 1993; Napier-Munn, Morell, Morrison & Kojovic, 1996; Jankovic, Valery & La Rosa, 2003). The suggested reason for this kind of relationship is that smaller particles have fewer flaws and higher strength than larger particles. Particles with fewer flaws and higher strength require higher energy for breakage to occur. One of the challenges most plants face is that of efficient energy utilisation in the liberation of the mineral from these complex ores. Conventional tumbling mills are not energy efficient in fine and ultra-fine grinding applications because some of the energy is spent on moving the charge and does not go directly into breakage. Stirred mills have been found to be about 30% to 40% more efficient and require a smaller foot print compared to traditional tumbling mills for regrind applications that require product size with P80s’ in the sub 45 µm regions (Radziszewski & Allen, 2013). Stirred mills are able to produce fine product because they can achieve a high number of stress events per unit time and volume compared to tumbling mills (Kwade, 1999a). To minimise energy usage without compromising product quality, the mining industry has adopted stirred milling technologies for fine and ultra-fine grinding (Radziszewski & Allen 2014; Kwade, 1999b). The south Africa platinum group metal (PGM) industry alone had over 40 stirred media mills installed by 2011 (Rule, 2011). Of that 40, 13 were in the ultra-fine grinding (UFG) application and the rest in main stream inert grinding (MIG)."

Jan 1, 2016

By A. F. Beck

Abstract Canada has opened up a geological province in ?Western Canada which offers a new .stimulus to oil exploration geophysics. The problems of instrumental technique, interpretation, and logistics involved in the exploration of this new territory are presented in this paper and some of the efforts being undertaken to overcome them are discussed. The scope of this programme, its possible trend and extent, especially when viewed .against the background of the exploration effort in the United States, is touched upon. Introduction The science of earth physics was first applied to the search for oil on this continent some twenty-five years ago when torsion balance and refraction seismic methods were initiated in the Gulf Coast area of the United States. Since that time advances in the various branches of the science have been sporadic as new fields for their use opened up in the search for deep salt domes as well as less well-defined geological structures; in the application to well logging as part of the exploitation of petroleum; and in underwater surveys, aerial surveys, etc. In the present paper, attention has been concentrated only on the Western Canada plains area because of the recent remarkable growth of geophysics as an oil finding technique in this region. The other prospective oil areas of the West Coast and the Eastern Provinces of Canada are at present of minor importance, although they will undoubtedly receive increasing consideration in the future as accessibility to markets becomes a major factor and more improved geophysical and geological techniques are developed. A vast province in Canada, covering some 655,000 square miles of prospective oil territory (approximately one-half of the prospective oil area in the United States), has provided the new sphere of activity for geophysics (see Figures 1 and 2). Included in this area are immense inaccessible, uninhabited frozen regions which pose a new problem in logistics and operational techniques.

Jan 1, 1950

By Paolo Farina

Slope monitoring radar has emerged in the last ten years as a leading edge tool for monitoring movements in natural and engineered slopes, thanks to its ability to rapidly measure slope movements with millimetric accuracy over wide areas in any weather conditions, obviating the need to install artificial reflectors. In recent years, slope monitoring radar has experienced significant improvements in its performances, mainly thanks to the use of different radar technology, such as Synthetic Aperture Radar (SAR), able to overcome some of the limitations of the first generation of radar and to provide higher spatial resolution, longer working distances and faster acquisition time. One of the leading applications of this technology is today represented by slope monitoring within the surface mining industry. Prominent international mining groups currently employ slope monitoring radar, based either on Real Aperture Radar (RAR) and SAR technology, for active and background monitoring of open-pit walls. The main technical features of typical slope monitoring radar based on SAR technology along with their possible applications are presented in this paper along with recent case studies of successful slope monitoring in open pit mines.

Jun 1, 2012

By H. M. Roscoe

Fifty per cent. increased lump coal production and at the same time a reduction of from 20 to 40 per cent. in explosive consumption. These results were achieved by the use of the rock-dust cartridge method of stemming shots in the Ruhr coal mines, as announced by Dr. Alfred Stettbacher in the September 1923 number of the Explosive Engineer. Immediately, the explosive and the coal-mining industries on this continent became intensely interested. Considerable experimental work has been carried on in a number of American and Canadian mines during the past year, by which our engineers have become assured that the use of rock-dust cart-ridges for stemming shots increases the efficiency of explosives and promotes safety in coal mines.

Jan 1, 1924

By F. Czerwinski

Mechanically fragmented chips of an AZ91D magnesium alloy were transformed into a semisolid slurry within the Thixomolding® system. Microstructural analysis of a material at various processing stages revealed that the cold deformation of the alloy, experienced during chipping, led to the recrystallization and growth of equiaxed grains which were subsequently converted to the globular structures by melting the grain-boundary network.

Jan 1, 2004

By Joël P. T. Kapusta, Liam J. Watt

The last extended copper smelting and converting survey dates back to the 2003 International Copper Conference held in Santiago, Chile. The following year, the Minerals, Metals, and Materials Society of AIME (TMS) started a new series in its Journal of Metals (JOM) called JOM World Nonferrous Smelters Survey devoting its first Part to Copper. The copper smelting landscape has significantly changed in the past 15 years, both in geographical terms with the shift of copper smelting production from the Americas to China and in technological terms with the growing adoption rate of Top-Submerged Lancing (TSL) technologies and the development and implementation of Bottom-Blowing technologies. A copper smelting survey update, even if not as in-depth as the 2003 Copper Smelting Survey, is therefore in order. The authors will review the latest trends in copper smelting technologies and production worldwide in comparison to the landscape of the early 2000s. INTRODUCTION This 2019 copper smelting survey is different from previous surveys as our data does not originate exclusively from responses to a questionnaire sent to all the copper smelters. Our data comes from several sources. We are therefore very thankful to the International Copper Study Group (ICSG) and Wood Mackenzie for sharing some of their information and to ENFI, Outotec, and Glencore Technologies for helping us cross-check our numbers for the Chinese smelters, flash smelting, Ausmelt, and Isasmelt technologies. Our survey presents data reporting from a total of 96 operating copper smelters from around the globe, which is significantly higher than the 50 surveyed in 2003. Although secondary smelting numbers have steadily increased over time, this paper focuses on primary smelting operations with copper concentrate as feed material. The list in this survey is still far from complete, with missing information from several known smelting operations. The total primary copper production tonnage of the smelters we surveyed amounts to 18.3 million metric tonnes from 29 countries representing 92% and 94% of total world primary production for 2018 estimated by ICSG and Wood Mackenzie, respectively. This representation has increased from 2003 when the total was 9.71 million metric tonnes from 23 countries accounting for 73% of world production. The trends presented and analyzed within this paper have stronger significance because of the increase in production accounted for. The Chinese and Russian smelter information collected is more detailed than years past. Our complete dataset is summarized in Table 1 at the end of our paper.

Jan 1, 2019