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By P. W. Ware

The majority of all refined copper is consumed to produce electrical conductors. Most copper conductors are drawn into wire from 8 mm ETP copper rod produced from high purity copper cathodes. Southwire Company has more than 40 years experience using, designing, fabricating and marketing a process for continuously producing ETP copper wire rod. This process is called the SCR® (Southwire Continuous Rod) process. Today, approximately half the copper wire rod produced in the world, or more than one third of all refined copper consumed, is produced using the SCR process. Southwire has sold 75 SCR copper rod mills to metal producers and wire manufacturers around the world. Southwire is North America's largest electrical wire and cable producer. Southwire operates a 48 metric ton per hour SCR® copper rod system in Carrollton, Georgia. This allows Southwire to provide technical support for existing SCR® system customers based on first-hand knowledge. Rod fabricators and their wire customers are always striving for copper rod that improves productivity. They are looking for improved surface quality, finer wire sizes and fewer wire breaks per ton of rod drawn. This paper will present a brief history of the SCR® process, a description and recent process developments.

Jan 1, 2007

By U. Martin

Advanced copper materials for conducting applications require an optimal combination of high mechanical strength at ambient and moderately elevated temperatures together with superior electrical and thermal conductivity. Mechanical alloying under repeated cooling of the milling vials in liquid nitrogen has been applied to produce ultra-fine grained (UFG) oxide dispersion strengthened (ODS) copper with a high yield strength at ambient temperature. In the present study ODS copper was manufactured by mechanical alloying of copper powder and 3% by volume of incoherent oxide dispersoids. During the high-energy milling a homogeneous distribution of fine dispersoid particles (diameter nearly 100 nm) can be achieved in the powder. Samples with a density of more then 97% of theoretical value were produced by uniaxial hot pressing under 650 MPa at 600°C for 20 minutes. The high yield strength at ambient temperature can be described by a linear superposition of the Orowan stress for particle hardening and of ultra-fine grain strengthening according to the Hall-Petch mechanism. Simultaneously, a best value of 75% IACS could be obtained for the electrical conductivity. The creep behaviour of ODS copper in the temperature range from 500°C to 700°C is described within the frame of diffusional creep deformation.

Jan 1, 2007

By M. Sabau

The Electrowinning Plant at INCO's Copper Cliff Nickel Refinery is a precious metals upgrading plant. The feed to the plant contains copper, nickel, cobalt, iron, significant amounts of precious metals and some impurities. Copper is the most abundant element in the feed. This paper describes the major equipment and process changes over the last twenty years, geared to improve the tankhouse operation, workroom environment and recovery of copper from the acidic solution. Copper is plated on to titanium blanks using explosion-bonded crossrods, animal glue as a levelling agent, and an organic surfactant for mist control. The installation of the stripping machine in 2001 required a number of changes: cathode and anode contacts were redesigned, flat bus bars were replaced with dog-bone type, spacer boards for cathodes and anodes were installed, longer anodes started to be used, and the plating cycle was extended from seven to fourteen days. A number of initiatives for improvement are being carried out. Explosion-bonded crossrods are being replaced with titanium-clad crossrods. The plan for the near future is to increase copper production by increasing current efficiency and current density. The possibility of lowering the iron concentration in electrolyte and changing the acid mist control method is being investigated.

Jan 1, 2007

By G. Viramontes-Gamboa

Approximately 70% of world copper reserves consist of the mineral chalcopyrite, and much international effort has focused on its study. Ultimate objectives include the development of environmentally friendly alternatives to smelting, and technologies to treat low-grade ores, for which concentration and smelting are economically unviable. Unfortunately, chalcopyrite leaching is inefficient in H2S04-Fe2(S04)3-FeS04 solutions, which is considered to be the most desirable oxidizing medium for leaching of copper sulfides, since the chemistry is well known, corrosion of industrial equipment is negligible, subsequent copper recovery by SXlEW is well established, and environmental impact is minimal. The main reason for this inefficiency is the self-passivation of chalcopyrite. We have devoted considerable effort in the understanding of this phenomenon, and have developed a predictive electrochemical methodology capable of establishing a priori the precise range of potentials within which chalcopyrite leaches and where it is passivated. Since potential control is a critical parameter in chalcopyrite leaching, this experimental methodology can be very useful for establishing the best conditions to leach chalcopyrite. In this paper, the scientific foundations of this predictive experimental technique are presented, and its practical application is demonstrated by comparing its predictions with leaching experiments from the literature.

Jan 1, 2007

By F. Lambert

"Amok Ltd./Cluff Mining operates a uranium mine at Cluff Lake in northern Saskatchewan. The project consists of one open pit and one underground mining operation along with a full-scale milling installation.The underground stoping operations are of the narrow vein type and are done between two levels 50 m apart. The mining method is undercut with concrete backfilling. Cuts are 3.5 m in height and can be as narrow as 1.4 m in width.Stoping operations are mechanized utilizing a CT-500E electric Microscoop marketed in Canada by Teledyne. The machine is only 85 cm in width and does all the mucking in stopes. Ore passes are provided in stope roughly every 40 m to 50 m.This paper describes the utilization of the CT-500E Microscoop in the company's underground operations and provides performance data related to the experience.IntroductionThe Amok Ltd ./Cluff Mining operation is located in the northwestern corner of Saskatchewan. The project started in 1980 with open pit mining and milling operations. In 1983, an underground mining operation began production . Today, the Amok Ltd./Cluff Mining installation produces 800 tonnes of uranium per year , which originates from both the open pit and the underground mine at about the same proportion."

Jan 1, 1990

By C. O. Aksoy

"Pillars left to ensure the stability of major underground coal mine infrastructure (shafts, drifts) often contain substantial quantities of coal. Recovery of this coal is an efficient use of the resource, but often presents safety hazards; pillar extraction destabilizes the protected structure, and can make its use dangerous. In this study, the stability of an active shaft at an underground coal mine situated in the Soma- Manisa region of Turkey was investigated during the recovery of the coal in the shaft safety pillar.A proprietary three-dimensional finite element analysis model (ANSYS) was used. An elastic-plastic material model utilizing the Drucker-Prager failure criterion was employed. The three-dimensional Drucker-Prager formulation was preferred over the two-dimensional Mohr-Coulomb model because it was thought to more accurately represent the strain hardening behaviour shown by most geologic materials.Stresses and deformations formed around the shaft support were estimated using the model and the results were verified by in situ observations. The results show that stress distributions around the shaft and the subsidence of the shaft support are influenced by the location location of the extraction front and the break angle of the overlying material."

Jan 1, 2005

By Didier Fohlen

Three Policy Shifts to enhance IFC?s Accountability ? Comprehensive and dynamic treatment of social, health, safety and environmental risks ?Covers a range of risks encountered by clients in emerging markets ?Framework to anticipate risks and to address them as they arise ?Includes community development, biodiversity, human rights ... ? Effective principles to guide an outcomes-based approach ?By clients and IFC ?Focus on broad community support and value-added sustainable development initiatives Enhanced governance, transparency and disclosure

May 1, 2006

By Chigova. Terence

In 2008, Anglo installed the Modular IntelliMine® System at its Kleinkopje Mine (AKK). As part of this deployment, Anglo also used the Change Management Consulting Service offered by Modular to ensure a successful installation. This paper outlines the benefits that AKK has realized through the deployment of the system, including a 15% improvement in tonne/kilometers per hour (TKPH). The mine benefited from the improvements provided by the system almost immediately by utilizing change management to more effectively integrate IntelliMine technology into their processes. This case study includes details about the deployed system, the implementation of change management, and recommendations to ensure success in future projects.

May 1, 2010

By R. Phillips, A. G. Doll, D. J. Barratt

"The Bond low energy impact (crushing) work index test is specified to be performed on rock specimens between 50 mm and 75 mm in effective diameter. NQ-diameter drill core, frequently used in mineral exploration programs does not meet that specification, it being 45 mm diameter or less.This paper reports the effect of performing the impact test on contiguous sections of HQ diameter and NQ diameter core, exploring the hypothesis that the contiguous intervals give equivalent results in spite of the core diameter difference."

Jan 1, 2012

By W. Grell

"In this paper, two methods of standardizing mill language are proposed; one is based on metric units and the other on English units. Tentative procedures for chemical and screen analysis based on published methods are proposed.Standard procedures for determining work index, and for leaching, flotation, and classification tests are outlined.Objects of Standardization:(1) to improve communication -(a) among gold metallurgists(b) with other branches of mineral dressing(c) with mineral dressing in other countries(d) with general scientific procedure(2) to improve mill control by -(a) standard methods of analysis (i)(ii)(iii)(b) standard methods of calcula tiort(c) standard accounting proceduresin the plantin the mill laboratoryin the assay office(3) to improve mill test work and investigationAreas of Standardization(1) Nomenclature or terminology(2) Measuring techniques(3) Test procedures(4) Accounting procedures"

Jan 1, 1966

By Xiaoxing Hu, Guibing Zheng, Yangge Zhu, Xingrong Zhang

"In China, more than 90 percent of titanium resources are reserved in vanadic titano-magnetite deposits. In this type of ore, the same elements such as Ti, Fe, Ca, Mg exist on surface of both ilmenite and titanaugite (the gangue mineral) because of isomorphism, which makes selective flotation difficult. Therefore, how to enlarge the floatability difference between these two minerals has always been a research emphasis and still needs to be studied further. In this paper, the pre-treatment methods using ultrasonic wave were proposed. The results indicate that ultrasonic treatment shows beneficial effect to enlarge the floatability difference, and the effect will be strengthened by extending the ultrasonic treatment time or increasing the ultrasonic power. The mechanism was investigated through infrared spectroscopic (FT-IR) analysis. Collector interacts with Ca and Mg which results in titanaugite flotation, after ultrasonic treatment, the dissolution of Ca and Mg is intensified, which leads to the lack of active points on mineral surface, so the floatability of titanaugite is depressed. Meanwhile, collector mainly interacts with Fe which results in ilmenite flotation, and the present of ultrasonic might promote its oxidation (Fe2+ to Fe3+), so the floatability of ilmenite after sonication is increased.INTRODUCTIONUltrasonic is the sound wave with frequency of 2 × 10-4 Hz~2 × 10-9Hz. Since the first International Symposium of Sonochemistry in 1986, the application of ultrasonic wave is more and more extensive. In researches about mining and metallurgy, various investigators have shown that intensive acoustic fields can modify the state of a mineral, leading to chemical or dispersive effects. Generally, the effect of ultrasonic vibration depends upon the nature of the mineral and also the way ultrasonic wave is applied (Celik, 1989; Ozkan, 2002). In addition, ultrasonic treatment usually plays roles of removal of reagents adsorbed layer from minerals and emulsification of flotation reagents when it is used in flotation (Nicol, Engel, & Teh, 1986; Slaczka, 1987; Djendova & Mehandj, 1992; Farmer, Collings, & Jameson, 2000; Gurpinar, Sonmez, & Bozkurt, 2004)."

Jan 1, 2016

By Daniel B. Leznoff

The cyanoaurate anions [Au(CN)2]- and [Au(CN)4]- are shown to be useful building blocks for synthesizing supramolecular coordination polymers. For the gold(I) unit, aurophilic interactions often increase the structural dimensionality of the system and can impart increased thermal stability to the metal-polymers produced. A series of polymers of the form M[Au(CN)2]2(Ligand)x have also been prepared and show large colour changes upon changing the ligand, thus illustrating a sensor-type application. Both building blocks can mediate significant antiferromagnetic and ferromagnetic interactions between transition-metal centres in the polymers. For the gold(III) unit, no metal-metal interactions are observed, although weak Au-N(cyano) interactions control the intermolecular packing. Several structural examples of cyanoaurate-based coordination polymers are presented, including 2-D and 3-D arrays and a supramolecular square.

Oct 1, 2003

By C. Díaz, A. D. Dalvi, C. E. O'Neill

Roast-reduction smelting (RRS) of nickel concentrate, combined with flash smelting of copper concentrate, was one of the process options that Inco considered as a means of meeting its 1994 sulphur dioxide abatement target at its Copper Cliff operations. RRS involves deep roasting the nickel concentrate in fluid bed roasters. The roaster off-gas is treated in a sulphuric acid plant, and the low sulphur calcine is reduction smelted with coke in an electric furnace to yield a sulphur- deficient matte. The latter material is converted to Bessemer matte in Peirce-Smith converters, with minimal evolution of sulphur dioxide, and the converter slag is reverted to the electric furnace. Excellent nickel and cobalt recoveries (Ire obtained. This paper discusses the development of RRS, including extensive commercial scale testing at Inco's Thompson Smelter, and its key operating parameters.

Jan 1, 1994

By Dirk van Zyl

The world is consuming more and more electronic products every year. This has caused a dangerous explosion in electronic scrap (e-waste) containing toxic chemicals and heavy metals that cannot be disposed of or recycled safely. But this problem can be avoided. We are pressing leading electronic companies to change; to turn back the toxic tide of e-waste. Every year, hundreds of thousands of old computers and mobile phones are dumped in landfills or burned in smelters. Thousands more are exported, often illegally, from the Europe, US, Japan and other industrialized countries, to Asia. There, workers at scrap yards, some of whom are children, are exposed to a cocktail of toxic chemicals and poisons.

May 1, 2008

By Greg Johnson

Maintenance needs information about assets to optimize availability and production needs information about performance and consumption to maximize output. In considering both these needs together as, ?Asset Optimization?, the information systems that support them are critical. The theory of Asset Optimization derives from the Lean Manufacturing concepts developed by Toyota, but some changes are required to apply this to mining operations. In particular, mining operations require automated systems due to their geographic spread and they need a strong emphasis on capturing under-performance losses as well as delays and stoppages in production. Leading metal miners and coal miners alike have applied these systems to good effect in the last 10 years. The concepts developed initially in minerals processing plants are now being applied to the mines themsleves as well as the mining logistics chain. Production increases of 5?10% are achievable with the right implementation and consideration of the some key lessons learnt in the last 10 years. Putting these lessons into action is one key step in the goal of optimizing asset performance and thus utilizing the resource at lowest cost.

Aug 1, 2013

By M. R. Henzinger, W. Schubert

"The quality of the backfill applied at a shield driven tunnel is of significant importance failure of the lining. The used material also affects the interplay between support and excavation behaviour.In this research the state of the actual bedding situation is investigated by an analytical approach, laboratory tests and numerical simulations. The numerical simulation using continuum methods have shown shortcomings. These shortcomings regarding the instability of large strain simulations restrict the possibility to reproduce the relocation of the backfilling material. The performed scaled model tests have shown that the regripping process of a double shielded tunnel boring machine affects the soil failure within the gap. With the analytical results the influence of the wall friction can be predicted. Therefore the angle of the failure surface can be determined. The results have shown that the wall friction significantly increases the failure angle. INTRODUCTIONFor tunnel boring machines (TBM) with single (SM) or double (DSM) shield, precast liningsegments are used as rock support. These segmental linings are installed within the protection of the TBM shield. In order to reduce the friction while advancing, the shield diameter is smaller than the diameter of the cutter head and therefore also smaller than the excavation boundary. The difference depends on the expected radial convergences. Since the lining segments are mounted within the shield the steering gap between the shield and the excavation boundary increases and is hereinafter called annular gap.In the process of tunneling in hard rock, the annular gap is usually filled with fine grained and closely graded gravel, termed as pea gravel. The backfilling process starts as soon as possible after the shield tail passes the lining. Due to the operational procedure within the working area of a TBM, a fully backfilled annular gap might not be established after every ring closure. This leads to an unfavorable distribution of the pea gravel leaving the segmental lining partially without bedding. Segmental linings can develop sufficient resistance only when properly bedded."

Jan 1, 2015

By Jacques Nantel

Mechanical-electrical personnel are present in all phases of the mining industry; the coverage is broad and diversified. Concepts of energy accounting are reviewed to pinpoint the sectors with a large energy consumption. Four sectors are reviewed: underground hard-rock mines, underground soft-rock mines, open-pit mines and mineral processing. In each sector, five or six technical innovations are analyzed as to their contribution to a more efficient use of energy.

Jan 1, 1979

By Ken G. Stowe, Stephen L. Chryssoulis, Joe Y. Kim

"Lead ions originating from galena during processing of complex sulphide ores migrate to ""cover"" the surface of sphalerite and iron sulphide mineral rarticles, and cause poor selectivity in differential flotation. Generally in sulphide ore processing, the lead activated minerals float in the Cu/Pb circuit. Subsequently, surface lead complicates the zinc flotation circuit by lowering the concentrate grade due to the co-flotation of lead- activated iron sulphide minerals. The effect of lead in the differential flotation of sphalerite from Cu-Pb-Zn and Pb-Zn ores is discussed. Plant and laboratory test data are interpreted by determining the surface composition of individual grains of sphalerite and iron sulphide rarticles using two surface analytical techniques, Laser Ionization Mass Spectrometer (LIMS) and Time of Flight-Secondary Ion Mass Spectrometer (TOF-SIMS). Cationic and anionic species on the surface were analyzed to elucidate the phenomena.IntroductionSurface properties play a critical role in many aspects of mineral processing such as flotation, flocculation, etc. An understanding of interaction mechanisms of different reagents (inorganic cations and anions, collectors, regulators, etc.) with mineral surface in an aqueous solution is a very important pre-requisite in achieving the desired selective flotation. In the flotation of complex sulphide ores, the flotation collectors respond to the activation of minerals such as sphalerite, pyrite etc. by heavy metal ions of Cu, Pb or Ag, which is a strictly surface phenomenon."

Jan 1, 1995

By G. W. Brooks

This short article is quite different to the general run of papers that are presented to the Institute, but no apology is offered because I consider that first-aid and mine-rescue work are of equal importance to many other subjects that are dealt with in our Transactions. Members of the Institute should be as much interested in the safety of persons engaged in the mining industry as they are in the practical methods of modern mining. We must not only do our best to conserve life and property by adopting every known device to that end, but we must also prepare ourselves so that we may take prompt and effective action when life is in danger, or when property is subject to loss. The need for such preparation in Alberta is perhaps greater than in most places where mining is carried on, and we must spare no effort to assemble at every mine men who are well trained in first-aid and mine-rescue work. The large area over which the mines are distributed renders central training stations out of the question, hence the need for local rescue-teams. Hospitals with skilled staffs, close enough to the mines to be convenient, also seem to be out of the question; therefore the greater need of a high standard of first-aid training for the people in our mining camps. The Government mine-rescue cars are supplied with the equipment necessary for training persons in this essential work and also for dealing with disasters should they occur. The question then arises: are there a sufficient number of men who are trained ? If so we can rest assured that what is possible to be done will be done. But if a sufficient number of trained men are not available much loss of life and damage to property is likely to result.

Jan 1, 1925

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