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By D. G. Ingram

This paper reviews the operating and maintenance practices at Bethlehem Copper from the commencement of operations in November 1962 to the present. Cost data and wear life of major components are also discussed.

Jan 1, 1979

By J. A. R. Faucher

"Autogenous grinding may be an efficient and economical solution to your ore comminution problem.An important potential economic advantage of autogenous mills results from the availability of very large capacity units.Autogenous grinding could be more economical in terms of both capital and operating costs.Satisfactory pilot plant testing and thorough economic evaluation are required for a sound decision in comminution plant selection.INTRODUCTIONMankind's first weapon was probably the wooden club, but men soon learned to shape, smooth and polish stone for tools and weapons by pounding and rubbing them with sand and water. It was only about four thousand years ago that rocks were first broken to concentrate, smelt and return the metals they contained. In spite of our recent great technological advances we still break rock in essentially the same manner that was used thousands of years ago - by pounding, rubbing and squeezing - and we still waste much energy and metal in the process"

Jan 1, 1969

By J. G. Cullain

In conjunction with the over-all goals of energy conservation at Inco Metals Company, a program of improvement in compressed air utilization was established. Air flows were monitored and compared to calculated requirements to establish efficiency by area. With the cooperation of area management, measures were implemented to reduce nonproductive usage. At the operation, annual savings in power consumption alone were 80,000 dollars. The program is being extended to other mine areas within the Division.

Jan 1, 1979

By J. Y. Kim, Kenneth Stowe, Stephen Chryssoulis

"A series of flotation tests was carried out on Brunswick Mining ore with various pH modifiers (soda ash, lime, KOH) and added ions (ferric, nitrate, sulphate) in the copper lead rougher circuit. The main objective was to identify downstream effects on sphalerite activation and subsequent zinc rougher flotation. Some significant differences in zinc flotation were obtained. Most notably, soda ash and nitrate ions had a positive impact and ferric ions a pronounced negative effect on selectivity.Selected products from the flotation tests were deslimed at 400 mesh, washed with methanol, air dried, placed in teflon vials purged with nitrogen and stored at -15 degrees C. Numerous liberated sphalerite and pyrite particles were selected under a stereoscope and placed in rows on indium foil. The surface compositions of the particles were analyzed with an innovative laser probe (LIMS). The very small analysis area of the LIMS enables the surfaces of individual grains to be characterized. In addition, the rapid analysis time allows a statistically significant number of grains to be analyzed quickly.Surface lead appears to play a major role in zinc activation/flotation. Possible mechanisms are proposed to explain the variations in metallurgical performance at the different test conditions.IntroductionAlthough the bulk composition of mineral grains is an important consideration for the mineral processor it is ultimately surface composition and topography (edges and dislocations preferred sites for reactions) that control reactivity in flotation and cyanidation (passivation, encapsulation and preg-robbing). Determination of the surface properties of particles from process streams poses a particular challenge for the surface chemist for a variety of reasons, including:"

Jan 1, 1994

By Bennett McLaughlin, Gille Brousseau, John F. Cook

"La Mine Bousquet commenced operations in October 1979. Mining has been by underground methods from two main zones which dip steeply to the south , Sub-level stoping methods with following fill are used.The orebody and immediate country rocks are sericitic and highly schistose. The intensity of schistosity varies significantly and poor ground conditions prevail, especially within the orebody,Initially few mining problems were encountered but in May 1981, significant damage occurred. A system of stabilizing pillars was introduced with improved support systems. Predevelopment in ore and pre-drilling of blastholes were reduced with extra footwall development.Damage has continued to occur on a regular basis particularly during the spring thaw. Generally, the adverse conditions have been successfully overcome.IntroductionMost of the mining problems that have been experienced at Bousquet have been caused by poor ground conditions . This pa per describes these conditions, considers the cause and describes the ways in which the conditions have been dealt with . Despite the problems, Bousquet is a successful operation which in 1983 produced 95,000 ozs of gold from 514,000 tons of ore."

Jan 1, 1985

By K. B. Han, S. Winkler, M. J. Benoit, M. J. Worswick

"Automotive heat exchangers are fabricated by forming multi-layered aluminum (Al) alloy brazing sheets into the desired geometry and subsequently passing the assembly through a furnace for brazing. As manufacturers seek to use thinner gauge and higher strength sheet to reduce vehicle weight, forming of the Al alloy sheets has become a challenge. Warm forming has previously proven to allay these forming concerns, but no consideration was given to the effect of increasing the forming temperature on brazing. Recently, it was shown that annealed sheet was more susceptible to the detrimental phenomenon of liquid film migration (LFM) during brazing if formed above 150°C, while work hardened sheets showed no increased susceptibility to LFM with increasing forming temperature, up to 250°C. In the current study, the brazing performance of simulated battery cooling plates was investigated. The plates were fabricated both from fully annealed and work hardened sheets. Brazing was assessed by microstructural evolution during a brazing cycle. The post-brazed microstructure varied with strain and forming temperature in plates made from annealed sheets, while no variation in microstructure with location or forming temperature was observed in plates formed from work hardened sheets.INTRODUCTION Since the 1970’s, one common method of fabricating automotive heat exchangers has been by forming multi-layered aluminum (Al) alloy sheets, and subsequently brazing the formed components together in a controlled atmosphere furnace. The Al alloy sheets used are comprised of at least two Al alloys roll bonded together, but can consist of additional layers, depending on the application; at minimum, the sheets are comprised of a core and clad layer. The core layer, often an AA3xxx alloy, remains solid throughout processing and provides strength to the assembly. The clad layer is always one of the AA4xxx series alloys which, due to their high silicon (Si) content, have a melting temperature range well below that of the core alloy. When the sheet is passed through the brazing furnace, the clad alloy melts to provide the brazed joint filler metal throughout the assembly, while the core alloy remains solid. In order to achieve cost and weight savings, heat exchanger fabricators have used Al alloy sheets with reduced thickness. However, deformation and brazing of these increasingly thin components remains a concern (Zhao & Woods, 2013). Furthermore, springback has been observed after forming sheets of higher initial strength (i.e. work hardened conditions), leading to flatness issues of formed components. Consequently, the ability to form high quality brazed joints is difficult in components formed from higher strength brazing sheets."

Jan 1, 2018

By T. McCallum, B. Wellbrook, T. Ratnaweera

Leaching of copper (Cu) concentrates produces elevated concentrations of Cu and acid, which makes solvent extraction (SX) processing more challenging. Maintaining extraction targets can be more difficult with higher pregnant leach solution (PLS) grades, and variability of PLS Cu and acid can lead to increased chemical iron transfer. Diluting concentrate leach feeds with an existing heap leach inventory makes SX processing easier. However, considerations about how much to dilute and where to distribute the flow into the SX configuration must be carefully evaluated, given their impact on metallurgical performance. In this paper, characteristics of a concentrate leach feed are discussed, along with considerations for processing by SX. Also reviewed are pilot plant results of concentrate leach distribution into SX and plans for commercial testing. INTRODUCTION Hydrometallurgical processing of copper concentrates continues to gain interest from the industry. Treatment by smelting and electrorefining continues to dominate, accounting for ~80% of global copper production, but is faced with its own challenges (Li et al, 2017). The case for increased hydrometallurgical processing has been discussed as high grade ore deposits are diminishing, capital costs for smelting are high, and the environmental aspects present challenges for sustainable practice. The hydromet copper industry is also turning a corner as easily leachable copper oxide deposits are depleting, and excess SX-EW capacity exists in certain regions. The transition to hydrometallurgical processing of copper concentrates will take a bit of effort as leaching of copper sulfides is difficult and byproduct credits must be considered. Various POX leaching processes have been studied and proposed to the industry as viable practices. Of the many processes, commercial use has been practiced with the Mount Gordon Copper Process, total and partial pressure oxidation by Freeport-McMoRan at their Bagdad and Morenci, Arizona complexes, the Sepon Copper Process in Laos, and the bioleach BIOCOP™ process in Chile (Dreisinger, 2016).

Jan 1, 2019

By D. O. Tansey

This paper will describe the mechanisms involved in delay blasting and how they are applied with the use of D.S.B. It will examine the control of potential damage resulting from detonations, and show how good fragmentation and efficient recovery of this material blasted can be achieved

Jan 1, 1979

By Sean Dessureault

Technological Revolution ?Information age ? brought about by: ?Low-cost processing, storage, information sharing ?Shared & integrated data ? Increasingly more sensors & data sources From data collection to data use ??Data mining??analyzing the huge volumes of data ?Key example used in MBAs: ?Wal-mart, Google Explosion of data, trickle of information ?Paralysis of action Outline Trying to provoke- What drives innovation now? ?Challenges in mining Data Action Approach ?Examples from research & consulting upon request Conclusions ?Unaddressed challenges (Research Opportunities)

May 1, 2006

By Jacob Wood, Robert Matusewicz

The Outotec® Ausmelt Top Submerged Lance (TSL) Process has achieved widespread commercial acceptance over the past 40 years for the processing of copper, nickel, lead, tin, zinc and precious metal bearing feeds. The continual development and evolution of the technology during this period has resulted in a more intense smelting process with higher energy efficiency and lower operating costs. More recently, considerable effort has been invested in decarbonisation of the process through improvements such as increased oxygen usage, dry feed injection and use of low-carbon auxiliary fuels. This paper covers a number of these recent advances to the technology and highlights their impacts on energy consumption and CO2 emissions for a range of non-ferrous smelting flowsheets. INTRODUCTION Relentless demand for improvements in the profitability, safety and environmental performance of non-ferrous smelting plants has driven a continual development and evolution of processing technologies in this industry. In response to these demands, a number of bath smelting technologies have emerged over the past 40 years and have been implemented for the treatment of primary and secondary feedstocks. The Outotec® Ausmelt Top Submerged Lance (TSL) Process (henceforth Ausmelt Process) is one such bath smelting technology which has been widely adopted in a large number of greenfield projects and brownfield plant modernisations (Wood & Hughes, 2016). Emissions of CO2 from the production of non-ferrous metals represent approximately 4-5% of global totals (Rankin, 2012), comparable with the almost 10% attributed to iron and steel production. Despite significant improvements in the energy efficiency of modern smelting technologies (Coursol, Mackey, Kapusta & Cardona Valencia, 2015), primarily through increased oxygen usage, further innovation and development is still required to address their reliance on fossil fuels such as coke and coal. Transformation of the non-ferrous smelting industry to low-carbon technologies and process flowsheets is lagging behind the power and transport sectors, which have witnessed significant growth in clean/renewable energy technologies to reduce CO2 emissions and address the issue of anthropogenic climate change (IRENA, 2018; IEA, 2018).

Jan 1, 2019

By Louise Laverdure

Outline ?Background ?Issues and considerations ?Why do we need to innovate ?Green Mining Initiative ?Footprint reduction ?Innovation in waste management ?Ecosystem risk management ?Mine closure and rehabilitation ?The Future

May 1, 2011

By P. Condori, G. Rech, J. Winnett

"Palabora Mining Copper has a unique ore body composition which unlike other copper ore bodies has three main components in significant proportions; these are copper bearing ore, magnetite and dolerite. The high content of dolerite, a hard barren material, creates a high proportion of pebbles which normally are recycled back to the mill. This action increases the mill bearing pressure and power progressively until corrective actions are taken.A logical action to solve the pebbles generation would be to incorporate a pebble crusher. This in fact was done however two fundamental issues were encountered; the high content of magnetite and existence of a cyclone classification section. Due to the high content of magnetite, metal detectors have not been able to work efficiently to separate tramp metal which causes damage to the pebble crushers. The existence of cyclones in the circuit had a detrimental effect on the final product when the pebbles crusher was online producing coarse sandy material.Due to the difficulties in treating pebbles via conventional procedures and the unique Palabora ore composition and characteristics, sorting technology was investigated at laboratory and pilot scale. It was found that a combination of optical and electromagnetic sorting could efficiently separate dolerite from the copper bearing and magnetite ores.This paper reports the findings of the laboratory and pilot scale work performed and discusses the additional benefits to the circuit."

Jan 1, 2012

By H. Sipilä, H. Vartiainen, H. Paarma

"The carbonatite massif of Sokli includes several low-grade Nb showings composed of ores and wastes as identified by routine analyses. More detailed lithologic proportions were determined in two orebodies in the Kaulusrova Nb-mineralized area by a careful geological study and by thorium radiation measurement on 10 cm-long drill core cuttings with a total length of 460 metres. The distribution of Nb in eight X-ray spectrometrically analyzed drill core sample intervals (totalling 35.8 m) was determined by analyzing the intervals semi-continuously by an X -MET analyzer. The geological studies suggest that Nb-mineralized bodies are feasible fo r the sorting of are and waste. This was confirmed by the semi-continuous determination of Nb on the X-MET analyzer.IntroductionThe Sokli carbonatite complex is located in eastern Finnish Lapland. The main ore of the carbonatite massif is a regolithic phosphorus ore in the weathered crust. Large-scale geophysical measurements and diamond drillings have also established several niobium showings within the magmatic carbonatites. Owing to the complicated geology of the massif, the niobium showings occur as irregular zones o r areas displaying complicated structure, texture, mineralogy and geochemistry (Vartiainen and Paarma , 1979; Vartiainen , 1980). The tonnages in areas such as this are large but the grades in-situ are low . The most intensely studied niobium showing is the Kaulusrova area.The exploitation of these showings depends on the feasibility of applying a sorting technique to upgrade the feed and to minimize the amount of material to be treated in the concentration plant. These possibilities o n the Kaulusrova area have been viewed by a detailed geological and X-MET an analyzing study."

Jan 1, 1985

By James F. Allan

"The Kipawa yttrium-zirconium prospect is located about 150 km south of Noranda, Quebec. Yttrium-zirconium mineralization occurs in an elongate, regionally metamorphosed and deformed peralkaline complex in the Grenville terrain. The mineralized zone, as defined by =.0.10% Y2O3, is 1300 m long and 10 m to 30 m wide. Zirconium content typically ranges from 0.50 to 1.20% ZrO2, The mineralized zone strikes northwest and dips 20 degrees to 35 degrees to the southwest. It occurs at the structural base of the peralkaline complex in syenite gneiss and calc-silicate rocks and is conformable with both the footwall contact of the complex, and the layering and gneissosity in the enclosing rocks. Minerals of economic interest are eudialyte (sodium-zirconium silicate), mosandrite (sodium-titanium silicate), britholite (calcium-silica phosphate), and a few other uncommon zirconium and titanium silicate minerals.The highest and most continuous yttrium grades occur in the upper part of the syenite gneiss unit in areas containing eudialyte, mosandrite and minor britholite. Yttrium also occurs in britholite in calc-silicate rocks and in mosandrite in syenitic rocks in the lower part of the syenite gneiss unit. Both the yttrium-bearing minerals and yttrium grades are erratic in the lower part of the unit. Zirconium is generally more uniformly distributed than yttrium. A peralkaline granite gneiss phase of the complex intrudes the syenite gneiss and possibly truncates it, and the mineralization, near the southern boundary of the mineralized zone.The mineralized zone is coincident with a radiometric anomaly and discontinuous yttrium and zirconium soil anomalies.More drilling and metallurgical studies will be required to determine the economic viability of the yttrium and zirconium mineralization at Kipawa."

Jan 1, 1992

By F. Duan, J. Pfarr, J. M. Goris

"The U.S. Bureau of Mines, in cooperation with the Homestake Mining Co. and the University of Utah, is conducting a field demonstration to evaluate the behaviour of rock masses supported with cable bolts. One of two rock masses being studied is supported with both conventional and birdcage cables. This rock mass is located between the 6500 and 6650 levels of the 45-48N stope, 21 ledge. The second rock mass is the hanging wall of the D-limb stope between the 3500 and 3650 levels near the Ross Shaft and is supported with conventional cables. The primary objectives of the project are to monitor the behaviour of the two rock masses during mining using extensometers and cable support strain gauges, after which the rock will be modelled using the finite-element code UTAH III. Field data will be used to verify the modelling. In addition, a comparison between the effectiveness of conventional and birdcage cables will be made.45-48N StopeThe 45-48N stope is located in the 21 ledge between the 6500 and 6650 levels and contains about 233 000 short tons of mineable ore. The orebody lies within the Homestake Formation and is very irregular being approximately 200 ft long and 75 ft wide. Between the 6500 and 6650 levels, it dips from 35 degrees to 60 degrees east with a near-vertical plunge to the south. Mineralization is characterized by arsenopyrite and pyrrhotite with minor gold. The contact between the Homestake and the overlying Ellison Formation creates a plane of weakness along localized graphitic layers. The footwall dips at approximately 60 degrees but between 100 ft and 120 ft above the 6650 level , the hanging wall flattens to almost 20 degrees causing a significant mining problem."

Jan 1, 1991

By Stephen Hardcastle

Personnel Heat Exposure Issues In Canada?s Deep Mechanized Mines ?Project developed in 2004 ?Base/precious metal industry identified heat stress/management as a major challenge affecting productivity and operating costs ?Project started in 2005 ?Current research nearing completion ?Guidelines, further data analysis and ?Communicating the Science? will continue into 2011

Oct 1, 2010

By N. Plint, M. Potgieter

The Anglo Platinum Mogalakwena North concentrator was one of the first three hard rock mineral processing applications to utilise a HPGR circuit in preference to a SAG milling circuit. This was driven by the extreme competence of the ore that had given rise to throughput issues on the original South Plant. Despite more than adequate capacity and performance of the individual comminution units, the circuit has struggled to obtain full design capacity. A thorough review of the integrated performance of the circuit revealed a wide range of bottlenecks and underutilised parts of the circuit arising from design issues. Interestingly, the major opportunities lie in materials handling issues and mismatch of loads about the circuit. This paper presents the high-level outcomes and the associated opportunities, and is pertinent to all HPGR circuit designs.

Jan 1, 2012

By Denis Landry

"RÉSUMÉAu cours de dix dernières années, la compagnie Maghemite a développé, expérimenté et breveté un nouveau precédé de concentration du minerai de fer à partir de la récupération d'hématite présente au bassin de sédimentation de la Compagnie Minière Québec Cartier.A partir de cette nouvelle technologie de concentration par induction, la compagnie Maghemite produit une poudre d'hématite qui est mélangée avec du strontium carbonate à un ratio de l à 6 en poids. Le mélange homogène est achemine sur un disque d'agglomération, et ensuite incorpore dans la fournaise de la Compagnie Minière Québec Cartier. Le temps de cuisson et la température (l200°C) correspondent exactement aux critères nécessaires pour la fabrication d'aimants de céramique, Grade 5, à partir de la poudre de ferrite.IntroductionMeghemite a débuté sa production de poudre de ferrite au printemps 1986et prévoit une production de 20 000 tonnes par année dans cette nouvelle usine. A très court terrne, une usine sera construite pour la production de cinq à dix millions de Iivres d'aimants permanents par annee et à long terme qu'une usine de fabrication par robotique de moteurs à aimants permanents, utilises dans I'industrie automobile. La poudre de ferrite à base de strontium est une compose ferro-magnétique forme d'une molécule d'oxide de strontium et de six molécules d'hernatite. Ce compose d'hexa fluorite de strontium a une force tres puissante et fournit la source d'énergie magnétique la moins dispendieuse comparée aux autres aimants permanents. L'utilisation des aimants de céramique formes d'hexa fluorite de strontium a connu un croissance phenornenale depuis 1970 pour atteindre un marché de 500 millions de livres par année en 1985.II n'y a aucune autre usine de production commerciale de poudre de ferrite à base de strontium au Canada. Le facteur determinant qui a favorise l'etabilissement a Port Cartier est base sur la réduction de 30% du cout des aimants de cerarnique provenant de notre poudre. Notre debouche majeur se situe aux États-Unis et vise la production des aimants de cerarnique pour les moteurs utilises dans les automobiles, les ordinateurs et les appareils ménagers, L'objectif de cette compagnie est de réduire le prix futur des aimants de cerarnique à environ 30% du prix actuel.L'usine commerciale de production de poudre de ferrite est maintenant opérationnelle. Le financement et la construction de cette usine sont Ie résultat de l'opération d'une usine pilote sur une période de 5 ans afin de récupérer l'hematite d'un haut niveau de pureté provenant de résidus de I'usine de bouletage de la Compagnie Minière Québec Cartier (CMQC) à Port Cartier. La fournaise de CMQC est utilisee pour chauffer les boulettes cornposees d'un mélange de carbonate de strontium et d'hematite d'un haut niveau de pureté en étalant environ 5 tonnes à l'heure de ces boulettes au-dessus du tablier de boulettes de fer dans une des fournaises fonctionnant à environ 450 tonnes à l'heure."

Jan 1, 1987

By Robert B. Parsons

"Canadian investment abroad has been the focus of considerable attention in recent years. Canadian mining companies have been heavy investors in Latin America and are taking a hard look at Central Asia and the Pacific Rim. This international flow of capital is not one-way however. Foreign mining companies continue to make substantial investments in Canada's mining industry. This month. Tax Notes addresses some of the main Canadian income tax implications of foreign investment in Canada.Foreign Investment in CanadaThere are two basic forms of foreign investment in a Canadian company: share capital and debt. The following comments deal with each of these investments separately. It is appreciated that the relevant tax legislation is, as always, quite complex, and that the notes that follow are intended only to serve as a guide. This article should not be relied on as a substitute for professional advice."

Jan 1, 1994

The Cadia mine is shifting from the open pit operation to the Cadia East underground block cave. The resulting increase in milled tonnes and the decrease in fines production through shifting to block caving require an increase of over 25% in installed power. This expansion is being accomplished via the installation of up-front crushing and HPGR milling of the ore, with the SAG mill receiving a secondary crushed feed. This design, criteria and rationale for selection is presented. Over the coming years, the mine will further expand capacity. The target is to accomplish this with minimal addition of installed power or use of fresh water. This presents a challenge that epitomizes the future constraints on our resource dependent and intensive industry. The approach and proposed options to this longer-term expansion are also presented.

Jan 1, 2012