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By C. Chongo, L. Little, Q. Mclennan

Since commissioning in 2005, First Quantum Minerals’ Kansanshi Mine in Zambia has produced over three million tons of copper and 1.8 million ounces of gold from a deposit with highly varied copper mineralization. The processing plant is complex with three independent flotation circuits, gold gravity concentration, atmospheric and high pressure leaching, solvent extraction, and electro-winning. For the first ten years of operating the plant, copper mineralogy was inferred from total copper and acid soluble copper assays, and various misconceptions developed about the mineralogy which impacted operational strategy and project decisions. In 2015, an on-site mineralogy section was set up with an Automated Scanning Electron Microscope, the Zeiss MinScan. This instrument has provided detailed mineralogical data that have debunked some of the mineralogy myths that had developed, highlighting the key underlying issues affecting processing performance. This has enabled the development of projects targeting losses of specific copper minerals in defined size classes, unlocking significant value. This paper describes some of the early misconceptions around mineralogy at Kansanshi processing plant, outlining projects that have benefitted from understanding copper mineral distribution. Learnings from Kansanshi are to be applied at other FQM sites, with a similar mineralogy program being set up at the Cobre Panama project. INTRODUCTION The deposit Kansanshi Mine is located in the North Western Province of Zambia, and it has been the largest copper producer in Africa for over a decade. The deposit occurs within a broad northwest trending antiform that can be traced for 12 km, hosted in a zone of complicated faulting, abundant vein injection, breccia development and down-dropped rock units that lies within Kansanshi’s mining license. The copper mineralization within the deposit is predominantly vein-hosted, although some is strata-bound, occurring in thin bands and veinlets parallel to foliation, and some is disseminated associated with albite-carbonate alteration (Gray, 2015). Supergene enrichment has led to significant variety in the copper mineral speciation. This alteration is complex, and has not followed the text-book principles with a neat layer of supergene mineralization overlying fresh hypogene ore. Rather, the occurrence and extent of oxidation and supergene enrichment is highly irregular throughout the deposit, sometimes occurring at significant depth in localized pockets and along fault lines. Gold mineralization tends to follow the copper within the deposit, but it is dominated by coarse-grained, free-milling native gold. The extent of copper oxidation – measured as the fraction of total copper that assays as acid soluble – is used to classify ore into three main ore types, named Sulphide, Mixed, and Oxide, which are then fed to three different primary crushers for processing in independent circuits.

Jan 1, 2019

By Michel Gauthier, Jacque Trottier

"ForewordA symposium on base metal deposits was held in Bathurst, New Brunswick, from June 10-13, 1990, sponsored jointly by the Geological Surveys Branch of the New Brunswick Department of Natural Resources and Energy, the New Brunswick Prospectors and Developers Association, and the Geology Division of the Canadian Institute of Mining, Metallurgy and Petroleum. Papers prepared for the symposuim are being published as a series of articles in the CIM Bulletin. This third paper (the first was by Fyffe, et al., in Vol. 83, No. 938, the second is in this issue) in the series presents an overview of the tectonic setting and geochemistry of base metal deposits in the Eastern Townships of Quebec.ABSTRACTIt is well known that the classification system of volcanogenic massive sulphides (VMS) is based upon their metal content. This metal content, the result of hydrothermal solutions circulating within strata underlying the deposits, is generally thought to be related directly to two parameters: (1) the nature of the underlying stratigraphic sequence; and (2) the physico-chemical conditions that existed at the time of the hydrothermal event. Furthermore, these two parameters are, in turn, related to the tectonic setting. One must bear in mind that these parameters are diachronous and evolve with time. These factors are considered in our analysis of the major VMS deposits of the southeastern Quebec Appalachians. This analysis will describe the time and environment of formation of these deposits and integrate them into an evolving paleotectonic model.VMS deposits in the southeastern Quebec Appalachians formed during three distinct metallogenic episodes. During the first episode, which involved early closing of the Iapetus Ocean and associated destruction of oceanic crust by subduction processes(Early Ordovician?), cupriferous VMS deposits hosted by pillowed, mafic (boninitic) lava flows were formed in immature island-arc systems (""Cyprus-type"", e.g. Huntingdon deposit).In the second episode, which also occurred during the closure of Iapetus but at a later stage (Early to Middle Ordovician), mature island-arcs formed and hosted polymetallic VMS deposits (""Kuroko-type"", e.g. Eustis deposit).Finally, during culmination of the Taconic and/or Acadian orogenies (Middle Ordovician and/or Devonian), transtensional basins, associated with tholeitic to transitional mafic volcanism began to develop. Major sedimentation occurred contemporaneous with volcanism, and within this framework polymetallic VMS deposits were formed (""Besshi-type"", e.g. the Memphremagog deposit).Although incomplete, the proposed paleotectonic model represents the sequence of the tectonic settings that prevailed during the formation of the VMS deposits of the southeastern Quebec Appalachians."

Jan 1, 1991

By D. Y. Kim

This paper shows an approach that a gondola-typed robot recognizes walls on building facades. It is applicable for autonomous or teleoperated building façade painting robots. The robot may react based on the wall classification data. This approach is based on 2D LRF(two-dimensional Laser Range Finder). The robot acquires relative distances to walls, and a Kalman filter decides correspondence of walls. An ARS(Attribute Reference System) sensor helps convert LRF coordinate to global coordinate. The experimental results demonstrate the conversion of LRF data.

Aug 1, 2013

By J. C. Roy, S. Couture, C. Barbeau

The chemical composition of the asbestos tailings from different mines in the Eastern Townships of Quebec are fairly uniform in composition. The serpentine minerals antigorite and chrysotile form about 85 to 90 per cent of the total. Iron oxides add another 7 to 10 per cent; magnetite represents about 70 per cent of the oxides. Chromite is present in amounts of about 0.5 per cent. The average contents of elemental magnesium, iron and nickel are 23, 6 and 0.25 per cent respectively.

Jan 1, 1972

By A. Glover

As the demand for natural gas as a prime global energy source continues to grow, the search for new sources of the fuel spreads into geographical areas that are more remote from the marketplace. Along with this comes the need for longer and ever more efficient pipelines. This requirement for higher value in natural gas transportation is satisfied to a large extent through the application of high strength technology and innovative design approaches that support increased design and operating pressures. This paper reviews the latest accomplishments and successes in these technologies for use in gas transmission. It also explores some of the technologies which are targeted for the future to allow the industry to achieve even higher benchmarks in reliability and cost-effectiveness. The central element in the theme of high strength technology for gas pipelines is that of high strength steel. From tensile strengths of Grade 359 a few decades ago, more and more operators are now specifying Grade 550 linepipe for their large diameter projects. As well, Grade 690 steel is operating successfully in limited transmission applications and Grade 825 has recently been installed. With the introduction of the latest high strength pipe comes the need for high strength fittings. The industry's first Grade 550 fittings were recently specified and installed on a project with Grade 825 line pipe. High strength materials can only be implemented successfully if compatible design and construction processes are in place. The latest developments in strain- and reliability based design will be described as well as the corresponding advancements in welding and inspection technology.

Jan 1, 2005

By David Green

"This paper describes Outokumpu's Tank Cell concept using the unit reactor principle and operating experience gained in various applications. Presently the tank cells used range in size from 35 t pilot size to 100 m' (3500 cuft). The paper discusses operating experience and results from commercial installations in copper and zinc rougher and cleaner services.The key feature of the Tank Cell described is the effective control of the froth phase and resulting possibility to operate on an improved grade recovery curve by manipulating the control variables."

Jan 1, 1995

By G. C. Weatherly, D. S. Wilkinson, A. M. Limarga

Competition between stress generation and relaxation mechanisms during the oxidation process has been observed. However, the nature of the intrinsic growth stress in thermally grown scales is not well understood. In this talk, we will propose a conceptual model to calculate the intrinsic growth stress based on the analysis of stress-driven diffusional process of oxygen ions along the oxide grain boundary. The calculated stress, which is considered to originate from the constrained lateral expansion of the oxide, is in agreement with a range of experimental observations.

Jan 1, 2004

By D. Kim

Kennecott operates one of the largest and most modern copper refineries in the world at Magna, Utah, USA. The inputs to the refinery are anodes produced at Kennecott Smelter, which has extremely high contents of lead and bismuth. In order to minimize undesired effects in the electrolytic refining process, unwanted impurities, especially bismuth, must be controlled. This paper describes the process development of practicing state-of-the-art quality control and presents the pilot test results of using the MRT Technology for Bi production.

Jan 1, 2007

By M. Uszko

Methane drainage and ventilation methods of methane hazard mitigation are used in the coal mines of Kompania Weglowa S.A. Over 22% of methane released during mining activities is captured by methane drainage systems and transported to the surface. In this article we present development plans for utilization of methane captured and transported to the surface by methane drainage systems. The results of research on the possibility of economic utilization of methane concentrated in ventilation air that leaves the mine through fan diffusers are also described.

Aug 1, 2013

By Y. Kocaefe, D. Kocaefe, G. Ergin

Filtration efficiency depends strongly on the wetting of the bed media by aluminum. This project was undertaken to study the wettability of different types of bed media (tabular alumina) using sessile-drop and infiltration techniques. The samples were analyzed using optical microscopy, SEM, and TEM to study the chemical interactions. The results indicate the spinel formation at the interface. This paper presents some of the findings which compares the two methods and gives the results of the analyses on the wetting of alumina by aluminum.

Jan 1, 2004

By B. Vorobyov

A Canadian company, Sight Power Inc., has developed a revolutionary, fully automated shaft monitoring and inspection system for deep-level mining based on a 3D mobile laser scanning technology. It consists of a special hardware unit and proprietary software with Artificial Intelligence elements for object recognition, features identification and change detection. The main purpose of this system is to significantly improve the safety of underground mining as well as to increase the available hoisting time thus generating substantial additional revenue for the mine.

Aug 1, 2013

By M. J. Nicol, C. van Wensveen

The kinetics of the oxidation of thiosulfate by copper(I I) in ammoniacal solutions have been studied in the presence and absence of dissolved oxygen. The formation of an intermediate mixed ammine/thiosulfate copper(II) complex ion has been confirmed and the rate of the reaction monitored by simultaneous on-line spectrophotometric, dissolved oxygen and potentiometric measurements. The rate of the anaerobic oxidation of thiosulfate by copper(II) was found to be orders of magnitude slower than that in the presence of dissolved oxygen and is inhibited in the presence of ammonia and anions such as sulfate and chloride as a result of competition with thiosulfate for the axial coordination sites on the copper(II) tetrammine complex. In the presence of dissolved oxygen, it was found that the copper(I) thiosulfate complexes are only very slowly oxidized while the copper(I) diammine complex is rapidly reoxidised to the copper(II) state. Thus, the initial rapid reaction with copper(II) leads to a pseudo steady-state condition in which the concentration of copper(I) is relatively constant and the rate of oxidation of thiosulfate can be predicted from the measured rate of oxidation of copper(I) by oxygen in ammoniacal solutions. The effects of the concentrations of ammonia and thiosulfate on the oxidation rate can be rationalized on the basis of the above coupled to the species distribution of copper(I) in the ammonia/thiosulfate system. It is shown that, with relatively simple measurements of dissolved oxygen and copper concentrations, the rate of oxidation of thiosulfate can be predicted under typical leaching conditions.

Jan 1, 2005

By C. A. Clark

The Chagres Smelter is located 80 kilometres north of Santiago - Chile, in the middle of an agricultural valley which is also one of the poorest districts in the country. This condition sets the main focus for the smelter's Corporate Social Responsibility (CSR) programmes, which ultimately aim at building self sustainable social and economic capital in accordance with the local capacities. With the help of Anglo American's SEAT (Socio Economic Assessment Toolbox), a corporately developed instrument designed to help the operations understand the needs of the communities and the impacts of those operations, the Chagres Smelter implemented several programmes, such as the CETTA (Experimental and Applied Technology Transfer Centre) programme. This project started in 2003, and consists of creating a centre for the transfer of sustainable techniques and skills for the small agricultural and livestock producers that live in the rural areas near the Chagres Smelter. Its main impacts are: Improved production quality (goat cheese and bee honey) and access to relevant markets, improved training and self-sustainability levels of producers, enhanced socio-economic level of the District's inhabitants by improving their income earning opportunities and technical knowledge, creation and promotion of a local brand as a symbol of quality products from the valley and a positive environmental impact of good breeding and native flora protection practices in the area. Other relevant social programmes are the 'Environmental Strivers', which created a recycling centre in the community; and the 'Beautiful Valley" project, which provides management knowledge and skills to local youngsters and leaders who can contribute to finding solutions for local environmental needs.

Jan 1, 2007

By K. Bachmann, M. Rudolph, U. A. Peuker, H. H. Duong, T. Heinig, T. Leißner, H. Schubert, Helmholtz-Institute Freiberg for Resource Technology, Technische Universität Bergakademie Freiberg

"Minerals can be liberated by random fracture of particles into smaller fragments or by detachment along phase boundaries. These two mechanisms represent borderline cases. When ores get comminuted the liberation of minerals is achieved to some extent by both mechanisms. This article describes a method to determine the extent of transgranular and intergranular fracture on surface exposure of minerals based on 2-dimensional liberation analysis.The approach uses the non-biased surface information like phase specific surface area (PSSA), phase specific free surface (PSFS) and phase specific locked surface (PSLS) of minerals and their change with comminution. The amount of transgranular and intergranular fracture on surface exposure can be calculated using the phase specific surface parameters.A sedimentary rock (apatite ore), an igneous rock (nepheline-syenite) and an artificial material (copper slags) were ground to different fineness. Based on the mineral liberation analysis (MLA) of feed and products, the extent of phase boundary fracture on the surface exposure of the minerals is studied.INTRODUCTIONMinerals can be liberated ether by comminution or by detachment (Gaudin, 1939). Liberation by comminution is a random fracture mechanism, which is not being influenced by ore texture, grain boundaries and mineral features (transgranular fracture). Liberation by detachment represents a fracture along grain boundaries (intergranular fracture). Random fracture often is named as the dominating mechanism for the liberation of ore minerals. This has been the basis to simplify models for liberation modelling (Barbery, 1991; King, 1979; Meloy, 1984) assuming that the probability of cracks moving along grain boundaries is zero. Thus, no interfacial area is lost during comminution."

Jan 1, 2016

By T. H. Adair

"IntroductionCONTINUOUS casting of ferrous and non-ferrous metals is not a new innovation. Patents describing machines for continuous casting are on file as far back as the year 1842. In the middle of the last century, Sir Henry Bessemer conceived and built a continuous casting• machine for the production of mild steel sheet.The production of billets and slabs of both non-ferrous and ferrous metals is being carried out by the continuous method on a fairly large scale on this continent and abroad. At present, the volume of production of •copper and aluminum and their alloys in billet and slab form is much greater than the continuous casting of steel products. The new installation of a continuous casting unit at Atlas Steels, Limited, is designed primarily for the casting of alloy steel billets and slabs.As an introduction to the art of continuous .casting of metals, it is interesting to examine a few of the many devices which have been developed. As previously mentioned, Sir Henry Bessemer constructed a machine for the direct casting of mild steel sheet. His discoveries and ideas of continuously casting steel formed the foundation for the work of other pioneers in this field, all of whom have contributed to the improvement of this art through the ensuing years. The machines which will be selected for examination are those of Bessemer, Poland-Lindner, Williams, Ennor, and Junghans. The last unit to be discussed will be a modification of the Junghans machine recently installed at Atlas Steels."

Jan 1, 1954

By Fathi Habashi, Ahmet Deniz Bas

"The mechanism of leaching of semiconducting minerals such as PbS, ZnS, UO2, etc., has been the subject of intensive speculation by hydrometallurgy researchers in the early 1950s who assumed the formation of intermediate surface complexes that could be neither separated nor identified by physicochemical techniques. The electrochemical theory of leaching introduced in the late 1960s resolved this problem by comparing the leaching process to a corrosion phenomenon similar to the corrosion of metals. Few years later, experimental evidence showed that anodic and cathodic zones are formed on the dissolving mineral although no electric current is imposed on the mineral during dissolution. A discussion of these findings is outlined.INTRODUCTIONIn the early 1950s researchers realized that kinetic studies for leaching ores are as important as thermodynamic calculations. It was also during this period that the concept of species adsorption on mineral surfaces has dominated the interpretation of the mechanisms of most reactions. This may have been due to the fact that many researchers of this period came from the mineral dressing sector and were influenced by flotation theories. However, when the knowledge of lattice defects and the semiconductivity of minerals became known and their importance in extractive metallurgy was realized, there was a need to explain the leaching reactions in light of these modern theories (Habashi, 1969, 1970). Semiconducting minerals of importance in metallurgy are two categories: the sulfides such as those of copper, lead, zinc, and the oxides such as those of uranium."

Jan 1, 2016

By C. Gordon Saunders

"The ungraded-fibre mill is located at the mine site and has a rated capacity of 6,600 tons of ore input and 1,200 tons of ung1•aded fib1 •e product per day. Power for operation is obtained from a diesel generating plant located on the site, which has a capacity of 5,300 kW. The preliminary milling process consists of prima1•y and secondary crushing, drying and temporary storage of plus-1 1h -in. material. The final milling processes are two stages of crushing and three stages of screening, with air-lift separation of the fibre from the host rock. The central mill building also houses a machine shop, mill maintenance shops, a mobile equipment overhaul shop, an engine and majo1•-component overhaul shop, and a warehouse. Major changes to the milling ci1•cuits since start-up have been the addition of a larger secondary cone crusher, ct third dryer, adding a rotary distributor to the feed of the screening section and adding an automatic start-up sequence for all equipment except crushers and fans. The operation of the mill is coordinated from a central control room, where a ""mimic"" panel indicates the operation of all major units in both the ore preparation and the screening sections. Product quality is controlled by continuous sampling and frequent labo1•atory analysis, which provide data fm• the adjustment of aspirating hoods and mill feed rate. Operating problems unique to this location, and common to a sub-arctic environment, are discussed."

Jan 1, 1976

By M. Potesser

In the past, different furnace types have been developed for use within the copper industry, with two common anode furnace designs typically used in copper smelting plants worldwide: the tiltable reverberatory furnace (KPO) generally used for the secondary copper industry and the cylindrical or drum type anode furnace (TRO) for handling a liquid blister charge generated in primary copper production. The disadvantage of the KPO is its design related to the longer refining period, because of the low bath depth, however it provides good conditions in the melting period due to its large bath surface. On the other hand, small amounts of scrap charged into the TRO increase the melting and dissolution period, but it provides good conditions for the refining period. The newly-developed elliptical furnace concept (TRE) offers the advantages of each of these furnace types. The special design allows melting of the scrap more efficiently than in the KPO and refining the liquid copper more efficiently than the TRO. This paper shows a metallurgical comparison of the three furnace types in regard to the melting period by heat technological considerations (optimized arch design) and of the refining period done by CFD with concentration on current, recirculation and dwell time of the gas in the melt. The paper outlines the possibilities for a reduction of the tap-to-tap time and energy consumption as well as for an increase of the production capacity, which can be achieved by applying the TRE instead of the conventional furnace designs.

Jan 1, 2007

By M. Kaya, A. R. Laplante

"Since the beginning of eighties the use of flotation columns has surged in Canada and abroad; the metallurgical superiority of columns over mechanical cells is in great part due to froth washing, which ensures higher gangue rejection and selectivity. Can wash water, which has proven so beneficial, be used in mechanical cells? Although froth washing technology was widely implemented in Soviet plants for bi tuminuous coal, and alusite, powellite, scheelite, molybdenite, etc. more than 25 years, it has been neglected in the western world. Published data suggest 10 to 15~ increases in grade and/or recovery with wash water in mechanical cells (Klassen and Mokrousov, 1963). There are at least three wash water plant applications in Zaire, Chile, and Canada, but little, if any, published information is available. This research work, which is the first extensive fundamental study related to froth washing in mechanical cells, attempts to answer the questions of how, how much, and where should wash water be added.This project was undertaken in three stages:1. Bench-scale laboratory tests with a 6.5 L Denver cell at McGill using a silica flour and a slime reject from Niobec (St.Honor6).2. Pilot-plant scale tests with a 65 L Denver cell at McGill using the silica flour and a complex Cu-Ni sulphide ore from the Strathcona mill of Falconbridge.3. Plant-scale tests with a bank of 2800 L Denver cells at Falconbridge Ltd. for complex Cu-Ni sulphide ore and Eastmaque Gold Mines Ltd. for Au tailing reclaimation."

Jan 1, 1989

By R. Pelletier, Herny. E., C. Allaire

Corrosion of refractory linings by molten metals is controlled by interactions between penetration and chemical reaction. Corrosion of aluminosilicates by molten aluminium is no exception. The early stage of corrosion can be described as a particular case of reactive wetting over a porous medium. Although the reactivity between aluminium and silica is great, which should improve wetting and penetration, the presence of air and the formation of a protective oxide layer disfavours initial penetration. This paper presents the results of an exploratory study on the effect of some parameters on the initial stage of aluminium penetration. Penetration kinetics and metal intrusion tests have been performed on alumina and silica powders with pure aluminium and Al¬5%Mg. Capillary models are used as tools of interpretation. Penetration kinetics tests had a poor reproducibility and the kinetics itself can not be explained very well by the capillary-tube-bundle model. On the other hand, a capillary model initially developed for ice intrusion into freezing soils produced predictions in reasonably good agreement with intrusion pressure measurements. The effect of particle size and alloy composition can be predicted using this model. However, the effects of temperature and powder chemistry need additional interpretations to be rationalised. An unusual resistance to penetration of silica powder by molten aluminium have been observed in a series of experiments. This led the authors to the strange conclusion that oxygen should be seen as an excellent non-wetting agent and that there might be ways to use it in industrial applications.

Jan 1, 2004