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By J. E. Nesset, S. R. Rao, J. A. Finch

"For base metal sulphides, iron rejection starts in mineral processing. This review focuses on changes in plant practice specifically to improve iron sulphide rejection by control of contaminant ion effects and discusses selected general innovations in mineral processing that can be expected to play a role. One group of changes to control contaminant ions is in size reduction (the use of stage grinding and inert stirred milling) and another is in system chemistry (order of reagent addition and exploitation of the flexibility of sulphoxy reagents). Plant examples illustrate the successes, indicating that there are several options available. The general innovations start by considering the new tools for measuring gas dispersion properties and quantifying froth characteristics by imaging. Examples of their application to improve concentrate quality illustrate the potential. Other innovations stress adapting geostatistics to model variation in milling and flotation response to provide feed forward control and rigorous application of statistical experimental methodology in plant test work. An example from one concentrator shows improvements in concentrate quality from application of basic principles can be impressive.INTRODUCTIONThe more iron control (rejection) that can be accomplished in mineral processing the lower the subsequent metal extraction costs and environmental implications of iron disposal, particularly in hydrometallurgical processes. Iron rejection has been a contributing target to periodic attempts to apply mineral processing to nickel laterites and bauxites but the prime application is control of pyrite and pyrrhotite (iron sulphides) in the treatment of sulphide ores by flotation. In this paper some new concepts and innovations introduced in sulphide flotation plants over the past ten years or so (i.e., since a previous review [1]) will be outlined with examples of how they have contributed to improved “iron control”.To increase rejection of iron minerals, first the recovery mechanism should be understood. There are four principal ones, two physical in origin: 1, via locked particles (i.e., flotation of composite particles due to insufficient size reduction to liberate the minerals) and 2, through entrainment in the water reporting to the float product (an unselective process); and two originating from a response to the system chemistry: 1, true flotation (i.e., iron sulphides becoming hydrophobic) and 2, as a result of iron sulphides forming aggregates with hydrophobic particles (e.g., ”slime” coatings). There has been considerable effort to diagnose which of these dominates iron sulphide recovery; in many cases it is due to “chemistry”, in particular true flotation. The flotation effect often appears related to contamination by metal ions [1]. This can reduce selectivity in two ways: 1, metal ion species may activate iron sulphides, or 2, cause general depression which demands more vigorous flotation conditions (e.g., additional collector) with consequent loss of selectivity. This is where the review will start, by considering ways to control contaminant ions."

Jan 1, 2007

By L. Iacopetti, A. Calderara, M. Perego, P. Perrone, T. Furusawa

De Nora, a global leader in the development, manufacture and sale of all DSA® anodes based on titanium coated with mixed metal oxide (MMO) for electrochemical processes will present key advancements made to Self-Protected Anodes (SPA) for metal electrowinning. (DSA® is a registered trademark of Industrie De Nora S.p.A., Italy). In 2017 pre-commercial demonstration cells were operated in industrial environment. The program’s focus was to fully demonstrate the SPA anode’s superior mechanical and electrochemical robustness during normal and induced dendrite shorting occurrences while providing quality of plating in commercial operation. De Nora specialists focus on key components, in particular the engineering of the self-protection system, DSA® anodes and catalyst formulation capable to cope with high levels of pollutants while providing long service life in the meantime. Results of field trials confirmed the expected anode performance and enabled the selection of the most suitable “SPA” structure, based on resistive protective elements. Summarizing the economic benefits to copper electrowinning tankhouse operation with De Nora’s self- protected all DSA® anodes are; Double-digits power savings Cobalt-free electrolyte operations Minimal dendrite shorting damage incurred at the SPA anode Smoother, uniform cathode deposits with tangible improvement on current efficiency Tankhouse operations producing lead-free copper quality cathodes, in addition to elimination of lead waste for improved operator health and environment. INTRODUCTION De Nora’s engineered “Value Technology Package” (“VTP”) for electrowinning, consisting of our DSA® anodes coated with mixed metal oxide specifically formulated for copper electrowinning in conjunction with an advanced self-protected full titanium anode (“SPA”), underwent an intense field qualification program, inclusive of the behavior under massive short-circuits as part of the field investigation, with the goal to select and appoint the ultimate design configuration of “SPA”. Optimized wireless-based monitoring system was included in the field program, demonstrating good functionality for cell parameters monitoring and remote shorts detection.

Jan 1, 2019

By M. Fan, M. Mankosa, G. Luttrell

"Column and other non-conventional flotation approaches continue to provide benefits where conventional flotation processes have exhibited limited success. This is particularly evident with respect to flotation of ultrafine and coarse particles. Advancements in air sparging technology have provided the ability to produce finer bubbles than previously possible. The generation of finer bubbles coupled with the froth washing capabilities of a flotation column has demonstrated improvements in ultrafine particle recovery while simultaneously producing a high-grade float product. On the other side of the spectrum, the use of these sparging technologies while applying flotation fundamentals to a fluidized-bed reactor has increased the maximum floatable particle size up to and in excess of 3 mm. Benefits of higher recoveries and reduced reagent consumption have resulted from the use of these technologies. An additional benefit includes a reduction in plant grinding requirements. As such, this paper describes the application of Cavitation-Tube sparger technology and fluidized-bed flotation (HydroFloat). A review of data from industrial and pilot-scale applications is also provided.INTRODUCTIONConventional (mechanical) froth flotation is considered the workhorse of the minerals processing industry. This low-cost process makes it possible to selectively recover minerals by exploiting the difference in surface characteristics (e.g., wettability) of the valuable component and the waste material. Unfortunately, the upper particle size limit for flotation rarely exceeds 0.600 mm, and is typically maintained at less than 0.300 mm for most industrial applications. For many commercial base metal plants, the particle size range for optimum recovery is typically between 0.01 and 0.1 mm (Lynch et al., 1981). This finding is not novel. In fact, the effect of particle size on flotation recovery was studied as early as 1931 by Gaudin et al. who showed that coarse (+0.250 mm) and extremely fine particles (-0.010 mm) are more difficult to recover than particles of an intermediate size. The loss of recovery is due to inherent limitations associated with the flotation process, including bubble-particle adhesion and collision, detachment, buoyancy, and transport."

Jan 1, 2010

By A. Bamber

Canadian leadership in a global mining context will depend not only on entrepreneurship and best practice but also on technological innovation. This paper argues for more ambition and commitment to R&D for technological innovation in Canadian mining. It focuses on underground hardrock mining, where past R&D initiatives have simply not stood the test of time, and it is important to examine why. Concerns arise because industry’s commitment to R&D has not been sustained over time. Innovation through exploration, processing, and environmental technologies has been more significant. Meanwhile, R&D capacity and synergies in government institutions and universities have not been exploited. There is a need for more commitment, coordination, and collaboration by industry, governments, and universities. This paper examines some corporate models that have achieved sustainable innovation, along with some that have not. A strategy for innovation is discussed that relates to culture, commitment, coordination, and collaboration.

Jan 1, 2005

By J. A. H. Church

MR. J. A. H. CHURCH: The salient feature would seem to be that the thickness of the seam, in our coals at any rate, is the main factor in predisposition to spontaneous ignition. The evidence, incomplete it must be admitted, in the Saskatchewan and British Columbia fields, and complete in the Alberta field to my mind, shows this up very strongly. The German report on the upper Silesian coal fields definitely fixes the critical thickness at 13 feet, the British report goes far beyond this figure by stating that liability to ignition increases with the thickness of the seam over four feet. Before discussing the Alberta fires it would be well to note an error on page 12 -the probable cause of the fire in the Frank Mine should read "Spontaneous near fault. Heating first discovered 1909". Of the six fires attributed to spontaneous ignition all the seams were identical or in excess of the critical thickness mentioned in the German report. If there be any reason in the foregoing it is high time some forethought were taken to adopt some definite system of laying out the workings of such seams not so much on the outcrop districts as with a view to the future operation to the dip. Seams approaching 13 feet in thickness which to date have shown no disposition towards heating during the extraction of the outcrop areas may well cause infinite trouble or indeed total loss when the ventilating pressures increase as increase they must to the dip. This state of affairs can be combatted only by the adoption of a correct system of working and the provision of numerous airways of as large an area as may be compatible with the physical characteristics of the particular seam.

Jan 1, 1923

By A. Brown

IN INTRODUCING the subject of rock pressures, it may safely be assumed that mining men are only too familiar with the physical effects of strata stresses that accompany the extraction of minerals. It may be further assumed that they have, as individuals, arrived at certain conclusions regarding their nature, based upon years spent in observing such phenomena and in learning how to continue mining in spite of them. Such hardly won experience forms the core of what is often referred to as 'pit sense'. This essential type of knowledge is not ?based on theoretical considerations, nor can it be found in text books. It is highly individualistic in nature and almost impossible to pass on from one generation to another in terms of precise rules for guidance. It is this aspect of individual judgment based on practical experience that has led to the significant phrase The Art of Mining.

Jan 1, 1956

By L. W. Hamel

"DUST CONTROL - GRANISLE COPPER LIMITEDINTRODUCTIONGranisle. Copper Limited is located in the north-central region of the Province of British Columbia, approximately 200 road miles north-west of Prince George. Mill startup was in November, 1966, at a rate of 5,000 tons per day, expanded to 13,000 in 1973. The primary crushing rate is 1,200 tons per operating hour, and the secondary 750, and they can be operated jointly or separately.DUST COLLECTION SYSTEMS There are seven dust collection systems ventilating the crushing and grinding complex. The individual pickup points are depicted on Figure 1 -""Crushing Plant Flowsheet"", and Figure 2 - ""Concentrator Flowsheet"", e.g. 1A, 1B, 3C, etc.System No. 1 - Primary Crusher The feed rock box of the Allis-Chalmers superior 42-65 primary crusher is ventilated by 19,000 CFM of air exhausted directly to atmosphere by a Sturtevant 426 M fixed discharge fan.No. Dust Pick Up Point CFM lA Crusher Feed Rock Box 19,000System No. 2 - Primary Crushing and Screening System No. 2 ventilates the primary crushing and screening equipment. A total of 19,000 CFM of air is exhausted by a Sturtevant 426 M fixed discharge fan through a Howden Type S - size 75 cyclone locally modified for wet scrubbing."

Jan 1, 1976

By A. D. Hunt

THIS PAPER will review Canada's fossil fuel situation as we understand it today and indicate some of the options available to meet our energy requirements during the next 15 years. It would therefore be helpful to examine Canada's total energy requirements and discuss the un certainties of the data base on which we must base future energy investment decisions. On the world scene, Canada is at the top of the energy-consuming nations, using about 49 bbls of oil equivalent per caput/ year. This appears to be slightly ahead of the U.S. and of course much higher than that of many countries. It is generally accepted that there is a more or less direct relationship between energy consumption and material standard of living. However , as we know, Canada, when compared with other industrialized countries on a GNP, an individual-income or some other standard basis, is lower in the list. This situation may be explained by our more severe climate and a relatively small population distributed over a land mass second only to that of the Soviet Union.

Jan 1, 1977

By L. C. Graton

Introduction The Porcupine district of northern Ontario has yielded over $300,000,000 in gold during its twenty-three years of mining operations. It thus ranks among the foremost gold producing areas of the world. Of this $300,000,000 already produced from the District, the Hollinger mine has furnished over 60 per cent and stands as one of the greatest gold mines of all time. In 1929, the Hollinger Directors decided to supplement the current geological and development work by an intensive investigation of the geology of the mine. This special study, begun in June of that year, was completed in October, 1932. An account of the geology of the mine in a degree of detail commensurate with the intensity of the study is in course of preparation. But the widespread interest manifested at the present day in gold occurrence generally, in Canadian gold deposits, and in the specific results of the investigation at Hollinger, appears to justify the immediate presentation of a highly abridged summary of our principal findings, insofar as they relate to the more general and scientific phases of the geological situation. Those conclusions having direct bearing on operating and exploratory policy are not dealt with here. The present preliminary paper, therefore, records chiefly the conclusions reached, with little incorporation of supporting argument or evidence. While intended to give a reasonably balanced perspective of Hollinger geology, the condensed presentation naturally emphasizes those views which are not in complete accord with accounts hitherto published regarding this district.

Jan 1, 1933

By R. L. Brown, E. A. Swanson

THE Buchans ore bodies are located in central Newfoundland, three miles north of Red Indian lake. The townsite of Buchans was named after a Royal Navy Captain who, while attempting to make contact with the Beothuck Indians, camped in the area in 1820. Ore was first found at Buchans by a Mic Mac Indian, Matty Mitchell, who discovered one of the three small orebodies in the bed of the Buchans river. The Anglo-Newfoundland Development Company, which holds mineral rights in the area, developed the orebody, but was forced to give up the venture because of difficulties encountered in separating the various sulphides. The American Smelting and Re-fining Company developed a flotation process which was capable of economically separating and concentrating the various sulphides, and, in 1926, they took a long-term lease on the property.

Jan 1, 1962

By B. Ignasiak

Laboratory studies suggest that improvements of coke strength brought about by pre-heating caking coals before carbonization accrue from inadvertent oxidation rather than from other low-temperature changes in the coal mass. Controlled oxidation of highly caking coal, followed by laboratory carbonization, produces cokes which, in terms of a laboratory scale tumble test index, are equivalent to those obtained from prime metallurgical blends. Appropriately formulated blends of exhaustively oxidized and fresh caking coal similarly yield cokes with strength indices comparable to those of cokes made from the same coal after oxidation under optimum conditions.

Jan 1, 1979

By A. Uribe-Salas, J. A. Finch, B. J. Huls

Froth depth or interface level is an important control variable in column flotation which can influence both grade and recovery. A common method of locating the level is based on sensing the hydrostatic pressure at one or more points along the column. The level indicated can be in considerable error, largely because of variations in froth and collection zone bulk densities. A portable conductivity probe has been developed to detect the position of the interface from conductance measurements across the interface. The location of the interface corresponds to the position where a large change in conductance is observed, which is primarily a consequence of the difference in gas holdup between the collection and froth zone. This probe detects the position of the interface to an accuracy of ± 5 cm. The probe can be used while the column is in operation, which allows for on-line recalibration of the level detection system. Results obtained in its application in a pilot-scale column (0.91 m in diameter) are described.

Jan 1, 1990

By P. R. Geoffoy, T. Koulomzine

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

Jan 1, 1960

By R. Khanna, K. Hyun Ko, A. J. Berkovich, J. Hook

"The co-pyrolysis of synthetic polymer polyethylene terephthalate (PET) and agricultural wastes (naturally occurring polymer-macadamia nut shell) was investigated in the temperature range 473K to 1273K using a horizontal furnace with an aim to understand their thermal degradation under isothermal conditions. In-depth characterization of pyrolysis residues was carried out using x-ray diffraction (XRD) and solid state nuclear magnetic resonance (NMR) for carbon structure, and through determination of the concentration of unpaired electrons using electron paramagnetic resonance (EPR). In previous studies, it has been found that PET thermally decomposes ~ 650K-700K, releasing (~80 wt % of initial weight) gaseous products due to random chain scission. In the case of macadamia nut shell, three types of byproduct can be obtained from pyrolysis: char, tar and gaseous products. In the co-pyrolysis of macadamia nut shell with PET in 50-50 wt% ratio, total product weight ratio could be modified with the addition of PET acting as a hydrogen source. This is because a recombination of thermal cracking products of cellulose could be suppressed by hydrogen from PET, which will later lead to an enhancement of tar formation. In addition, pyrolysis around 673K is sufficient for bond cleavage to occur in cellulose and lignin leading to the formation of negatively charged activated carbon with high surface area, providing bonding sites for volatiles evolving from PET. Therefore the co-pyrolysis may be able to enhance the product yield (tar/char/solid carbon residue) along with a reduction in the release of gaseous products. During the co-pyrolysis, temperature was found to have a significant influence on the kinetics of thermal degradation and solid residual by-products after co-pyrolysis.INTRODUCTIONPlastics are being used worldwide in a wide range of applications in the modern society; their usage has resulted in increasingly a massive waste problem. The production of most synthetic plastics requires hydrocarbons that are produced from petrochemicals derived from fossil oil and natural gas, a non-renewable source (Speight 2011). Currently, plastic manufacture utilizes ~4% of world oil and gas production, and it is expected to drive further increases in petroleum demand by 1-2% due to their large volume of manufacture (Hopewell, Dvorak et al. 2009). Landfilling and incineration of plastic waste are the two main routes to plastic waste management (Encinar and González 2008). In Australia, only 10% of waste plastics were recycled in 2006 (White and Hyde 2011). This means that large amount of fossil fuels from plastics has either been simply burned for energy recovery or buried in the ground. There is an urgent need for developing alternative avenues for recycling waste plastics. Our group at UNSW has carried out extensive research on the recycling of waste polymers as carbon resource in steelmaking including slag foaming and carbon dissolution from waste plastics into liquid steel at 1600°C; the effect of basic plastic characteristics such as chemical composition, structure, bonding network etc. was examined (Sahajwalla, Rahman et al. 2009)"

Jan 1, 2012

By R. Poulin, M. R. Samis

Real options valuation is an alternative net present value framework that is able to incorporate both management flexibility and dynamic project risks. In this paper, management is considering the development of a satellite low-grade zone while operations in a developed high-grade zone continue. If the lowgrade zone is developed prior to high-grade zone exhaustion, mine capacity must be expanded before additional production from the low-grade zone can be processed. This expansion can be avoided only if low-grade zone development is delayed until the high-grade zone is exhausted. The real option model presented here allows the development and capacity expansion decisions to be reconsidered on a discrete half-year basis. It delineates price regions, for given levels of high-grade zone reserves, in which it is optimal to develop the low-grade zone, defer low-grade zone development and abandon the mine irrevocably.

Jan 1, 2006

By M. Choy, A. Kadiayi, E. Magdzinski

"Design of engineering controls to limit occupational noise exposure rely on accurate calculation inputs. Sound in mines can carry considerable distances. Mine ventilation engineers rely on noise propagation calculations to estimate silencer performance criteria for key mine fan installations that are often in proximity to occupied areas of a mine and can remain in service for decades. The blasted and rockbolted walls of hard rock mining tunnels have unique acoustical properties. Underground testing in an operating metal mine in Sudbury, Canada was performed and results processed to characterize noise propagation in mines, with the goal of improving the accuracy of noise calculations.INTRODUCTIONAs mine operators continue to improve and promote workplace safety, addressing noise at fixed infrastructure locations is observed as increasingly common. Underground fans are important to consider in this context, as they are typically loud, in proximity to occupied and sensitive workplaces, and operate nearly continuously. Predicting noise propagation from ventilation fans within underground mines has long been a challenge, with few available resources documenting acoustical properties as calculation inputs. Other factors in addition to rock face absorption properties include tunnel geometry and distance from the fan, which play critical roles in characterizing the noise level at any given point away from the fan. By understanding and establishing methods to better predict noise dissipation along underground mining tunnels, engineers can design noise controls with a greater degree of precision and confidence to effectively protect workers from over exposure to noise.This paper investigates classical methods of predicting reverberant room and direct field noise propagation. These prediction methods are then compared to noise measurements taken within the Fraser Mine of Glencore’s Sudbury Integrated Nickel Operations (Sudbury INO) Measurements were taken at a depth of ~881 m (2,889 ft), along an ~300 m (984 ft) long blasted hard rock mining tunnel. The noise along the mine tunnel resulted from the intakes of two 900 kW (1,200 hp) ventilation fans with a combined exhaust capacity of 300 m3/s (630,000 cfm)."

Jan 1, 2019

By K. W. Fritzsche

The prosperity of any nation depends, to a large extent, on its natural resources such as oil, coal, 'metal, timber, waterpower, and fertile soil. Each one of these resources forms the basis of a huge industry. The mining and smelting industry ranks among the first since it paves the way for a number of other industries. The mines and smelters provide a market for electric power, coal, timber, and agricultural products: other industries in turn provide a market for metals and non-metals. The real pioneering, however, is done by the prospector who goes into the wilderness to search for the ores from which the metals are to be extracted for the use of men. Prospecting is an interesting and fascinating occupation. There are many difficulties and hardships in the way but the lure of gold and the vision of finding an outcrop that may develop into a large bank account, within a reasonably short time, will urge the prospector forward. Thus, on the outskirts of this northern hemisphere hundreds of prospectors are searching and toiling and of whom nothing is known or heard until they reach civilization and announce a new discovery. Then a mad rush takes place and everybody who can afford to go will take a gamblers chance and plant stakes in the neighbourhood of the new discovery, or wherever an outcrop of mineralized rock can be found, with the hope of winning a fortune.

Jan 1, 1925

By Mohammad Noaparast, Babak Fotoohi

"Due to certain advantages in (semi-)Autogenous-Ball mill circuits in most of the high-throughput ore grinding units of mineral processing plants, much attention is paid to optimize the mill performance. Despite the maturity of the grinding mill mechanical design, there had been made less attention to the efficiency of the grinding media in the past. In this research, the possibility of establishing a relationship between liner/lifter wear rate and variations in the composition of the iron ore (from Chadormalu mine) is investigated.Measurements and determination of liner/lifter wear rates and patterns concluded in recognition of critical liner segments exposed to much abrasion during the ore grinding. After metallurgical analysis of liner materials and correlation of wear rate with the ore composition, the homogeneity in the metallurgical microstructure of the alloyed steel (such as the uniform distribution and amounts of the constituent phases) was determined as the most influential factor in the response of the liner/lifter to the variations in the ore composition. Magnetite with greater abrasion index than hematite, in finer particles, is responsible for additional abrasion of liners; hematite with greater work index exists in the mill with larger particle sizes, thus it could produce wear on liner parts with less tolerance to impact as is the situation for martensitic steels.INTRODUCTIONThe mineralization in Chadormalu plutonic iron ore deposit is consisted of mostly magnetite, hematite, martite, apatite, quartz and carbonates. The average composition of the ore is presented in Table 1. In the processing circuit, the gyratory crushed ore reduced to 30 cm would finally be the feed to three similar 32’ semi-autogenous mills in parallel processing lines. The pulp in the mill would have the characteristics mentioned in Table 2. The quality of the mill output has its direct effect on the downstream processes either physically or chemically (e.g. in cycloning or flotation respectively). In order to take advantage of optimum performance for these circuits, a close control of the ore grinding conditions is necessary; because any shortages in throughput, liner/lifter damage or changes in ore composition could bring the unexpected casualties. In this work, it has been attempted to find (possibly) a reasonable relationship between variations in ore characteristics together with liner quality and the amount of wear rate in different liner/lifter segments of a semi-autigenous mill. Liner/lifter segments are supplied by three different domestic steel making companies. The alloy structure of the liners/lifters is made up of pearlitic chromoly steel."

Jan 1, 2005

By Avinash Kandalam, Markus Reuter, Jörg Kleeberg, Michael Stelter

The Top Submerged Lance (TSL) technology has obtained significant importance in the pyrometallurgy industry for nearly four decades. One of the advantages of TSL furnace is its high reaction rate, which is caused by splashing and turbulence of the melt. In contradiction, this phenomenon stands as a barrier for conducting experimental investigations to validate the simulation models. The highly turbulent and splashing environment in the TSL furnace is caused due to the immersion of the lance into the slag layer and thus the effect of the flame structure is directly related to the splashing, turbulence, reaction kinetics and life-span of the lance. Moreover, the material properties such as viscosity, density and the surface tension will also influence the flame structure. As a first step to understand the flame structure, attempts are made to generate a stable flame of the lance in an open environment. INTRODUCTION Top Submerged Lance (TSL) technology was invented during the 1970s at Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia by Floyd and Denholm. This technology was later commercialised and currently, there are about 100 TSL plants around the world commissioned by various licence holders such as AUSMELT (Outotec) and ISASMELT (Xstrata- Glencore Technology). Copper is the most produced non-ferrous metal followed by lead and zinc, see Hunt (2005). Today, a wide range of primary, secondary, and complex recycling materials are used as a feed material in the TSL, Alvear et al. (2010), Kaye et al. (2008). The working principle of TSL technology lies on inserting and submerging a lance from the top of a vertical cylindrical chamber into the slag layer. The lance is considered as the heart of the furnace, where the air and fuel are transported through two concentric tubes and are mixed in a combustion chamber, which is approximately 7 cm from the tip of the lance (considering the pilot-scale TSL furnace at the Institute for Nonferrous Metallurgy and Purest Materials - INEMET). The TSL furnace is very flexible with the type of fuel, feed material and the air input. The fuel can be natural gas/heating oil/fine coal particles and the air could be enriched with oxygen (Figure 1). The general mechanism of the TSL furnace lies on feeding the material from the top of the furnace and the material is pulled into the molten bath due to the high turbulent atmosphere, which results in high reaction rates. The thermocouples installed in the furnace (i.e. in the ceramic linings) allow the operator to know the temperature of the melt. For example, in the case of copper production the tapped material (i.e. matte/metal) can be transported to a settler for further processing or directly used.

Jan 1, 2019

By Oakley B. Gwillam

The study of leached outcrops as an aid in determining the character of mineralization beneath the surface is in its infancy. Practically all the work on this subject up to the present has been applied to the 'porphyry' copper deposits of the southwestern United States. Some work has been done also on the zinc-lead solid sulphide deposits of the western United States. The question has been asked, "Can this study be applied, and would it have any practical application, in northern Manitoba?" When one realizes the size of the unprospected territory in this Province and the consequent need for a cheap and rapid method of interpreting the countless outcrops which occur in order to discriminate between valueless iron sulphides and valuable sulphides of the base metals, it is readily seen that the study is of great value if it can be applied with a reasonable degree of surety. Augustus Locke, well known economic geologist of the southwestern United States and a pioneer in the study of leached outcrops of disseminated copper ore, has written much on the subject. Messrs. Blanchard and Boswell in a series of articles have dealt with the leached outcrops derived from lead and zinc sulphides in the western United States. Since this paper is essentially a comparison between the leached outcrops of the southwestern United States and those of northern Manitoba with the purpose of testing the adaptability of the study in this Province, an outline of the criteria used in the southwest will be of value to the reader.

Jan 1, 1930