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By Stephen Esposito

Outline ? Brief Overview of Solid Energy New Zealand ? Need for Integrated Risk Management at Solid Energy New Zealand ? Overview of Solid Energy?s IRM program ? What are the results and key learnings? Overview Of Solid Energy New Zealand ? 100% NZ Government Owned ? Produces 95% of New Zealand?s Coal ? Sales turnover USD150 million per year ? Sold 4 million tonnes of high quality coal in 2003 ? Coking and Thermal coals ? Exported 2 million tonnes of coal ? Significant international and domestic growth expected going forward

May 1, 2004

By A. Hussain

PAPER NOT SUBMITTED FOR PUBLICATION

Jan 1, 1987

By Md. Rashedul Islam

Magnetic data was collected from the Yeoju historical sites using the fluxgate gradiometer through six sites & several grids. We measured the vertical gradient by the FM256 Fluxgate gradiometer. The readings were logged every half meter. The obtained data were processed and treated to introduce a high quality magnetic image. The gradiometer results defined various positive and negative magnetic anomalies, which revealed the existence of several archaeological features of different shapes and sizes. The study of the process magnetic images give us a concept that the subsurface features are caved shape stone chamber tombs, burial mounds, deep room structure, Yeoju mausoleum, pagoda?s square foundation stones, walls etc. All these are superior work of early Goguryeo inheriting orthodox Silla style. So, the study area may have great archeological interest.

May 1, 2009

By M. C. Villeneuve

A numerical modelling approach was developed to explicitly simulate geomechanical characteristics of intact rock: mineralogy, grain size and fabric. The approach involved creating a representative constitutive model for each of three common rock-forming minerals: mica, quartz and feldspar. The constitutive models developed are valid within the low confinement realm of excavation boundaries, where tensile fracture processes dominate. The mineral types were assigned to numerical elements, which were associated with each other through an algorithm created in a finite difference model, FLAC 2D (Itasca 2007a), to simulate real crystal geometries and orientations. The numerical models were used in a parametric investigation of the geomechanical characteristics and compared with published observations of the rock yielding process in laboratory testing. This approach has allowed the explicit grain-scale investigation of the impact of geomechanical characteristics on rock yielding at low confinement, leading to an improved mechanistic understanding of excavation-scale rock yielding processes at excavation boundaries.

May 1, 2009

By Ian S. Thompson

"Exploration properties form a continuum from grass roots to those with favourable geology, geochemical and/or geophysical anomalies, mineralization, showings (prospects), and finally to those with defined mineral deposits. Often properties exhibit a composite of these categories.The most problematic to value are properties or deposits that are not economically exploitable at the time of the valuation, due to a lack of exploration, insufficient grade or tonnage, poor mining conditions, or the imposition of socioeconomic, environmental, or legal constraints.Various acceptable methods of valuing the range of all such mineral properties or deposits are reviewed. Some inappropriate methods are also discussed.BIOGRAPHYIan S. Thompson is President and Principal of Derry, Michener, Booth & Wahl Consultants Ltd. (DMBW), an independent consulting practice, specializing in exploration, ore reserve estimations, engineering and valuations of mineral properties.Mr. Thompson is a graduate in Honours Geological Sciences from the University of Toronto with over 35 years Canadian and International experience in mineral exploration and development, including the discovery of base metal. gold and uranium deposits.DMBW is affiliated with DMBW, Inc. in Colorado, and works with independent engineering and financial groups in North America, Europe, Australia and Africa.Mr. Thompson is a national member of CIM; the Associations of Professional Engineers of Ontario and British Columbia; The Geological Association of Canada; The Society of Economic Geologists; The Prospectors and Developers Association of Canada and the BC and Yukon Chamber of Mines.INTRODUCTIONThis paper is presented in response to the request of the Mineral Economics Society of the Canadian Institute of Mining and Metallurgy for a Review of Approaches to Valuation of Mineral Properties, as recommended by the TSE/OSC Mining Standards Task Force.Exploration properties with undeveloped mineral resources range from grassroots acreage without exploration history, to those containing mineralization (or a mineral resource) that is insufficiently explored, to well explored deposits which lack either continuity, or sufficient grade/tonnage, or have poor mineability or metallurgy, such that they are not currently exploitable at the time of the valuation. This does not imply that they do not have value."

Jan 1, 2003

By Serena Biella

Gold has received a growing interest as a catalyst for the selective oxidation of organic molecules using oxygen under mild conditions1. In the liquid phase application small gold particles (2.5-7 nm) deposited over different solid supports can be used but, like many other noble metals, their catalytic activity depends upon the nature of the support and the preparation metod2-5. In particular, gold on carbon is the preferred catalyst for the oxidation of the alcoholic 2-7 and the aldehydic7-9 groups and one of the best preparation method is the immobilisation of colloidal particles2-5,8,9. Suggested application of gold catalysis in fine chemicals production, tested on laboratory scale preparations, is reported in table 110. In order to produce more efficient catalysts for the liquid phase oxidation and to derive new insights into the reaction mechanism, we have made a comparison among catalytic systems based on different metals. The first effort was to test the activity, if present, of naked metal particles and then to study the influence of various materials commonly used as a support.

Oct 1, 2003

By P. C. Garg

"IntroductionThe Central Mine Planning and Design Institute (CMPDI) of India, started planning the extraction of thick seams highly susceptible to heating in 1977by the French method of sub-level caving and/or multi-slicing. Nitrogen flushing was proposed for inhibition of heating by the author in one such project - the Kotadih colliery.Inhibition of heating was unheard of in the Indian coal industry before 1977-78. The usual practice was to seal off a district or a part of the mine or the entire mine when spontaneous heating occurred. With very little equipment in a normal bord and pillar district and a low production rate, the financial loss in capital assets and in production did not warrant any serious thought for inhibition of spontaneous combustion. With the planned advent of longwall mining, particularly sub-level caving, with heavy capital investment as well as high production potential, the sealing of a longwall face due to spontaneous heating could not be considered an appropriate solution.Principle of Inhibition of SpontaneousCombustionFrench engineers have established that a fire will not break out when oxygen is 15% or lower in the general body of the air. However, once a fire starts, the percentage of oxygen has to be reduced to 2% - 4% to extinguish it. It is this principle which has been used at Blanzy Coalfield in France to inhibit heating and it is claimed that this has retrieved the integral sub level method of mining. Nitrogen infusion has been used in Frence since 1978 to keep the oxygen content below 14% in the goaf."

Jan 1, 1987

By Richard R. Klimpel, Simon Isherwood

"The industrial processing of ores containing gold and/or platinum minerals is generally mining site specific, e.g. McQuiston and Shoemaker (1985). The variety of various mineral processing techniques employed is extensive and includes size classification, gravity concentration, amalgamation, roasting, cyanidation, chemical leaching, ion ex-change/solvent extraction and froth flotation. Because of the relatively small quantities of Au and Pt that exist in the earth’ s crust, the economical recovery of Pt and Au often requires that the Au and Pt be associated with other industrially important minerals. This association of Au and Pt with other minerals can occur in very complicated mineralogical forms. It is probably safe to say that Au and Pt mineral concentration from natural ores represents some of the most complex metallurgical challenges facing the mining industry.Froth flotation is a technique that is receiving increasing industrial attention for the treatment of finely disseminated and/or associated Au and Pt minerals. The high throughput at relatively low capital cost, the potentially high selectivity, and the existence of a well-established technology for treating more abundant associated minerals such as base metal sulfides makes froth flotation an attractive processing alternative. Broadly speaking, the industrial oriented froth flotation experience with Au and Pt minerals exists in two major categories: 1) the flotation of Au and Pt associated with pyrite (or pyrrhotite) and 2) the flotation of Au and Pt associated with primarily Cu, Zn, or Cu/Pb/Zn containing sulfide ores.In the case of the precious metal association with pyrite (or pyrrhotite), much of the published froth flotation experience comes from South Africa. Typically, such processes are done using an acid side flotation with a collector such as mercaptobenzothiazole. The approach obviously is to float pyrite and hence recover associated gold. Generally the higher the total sulfur recovery the higher the gold recovery. Similar experiences of Pt associated with pyrite are a lot less common mineralogically and hence less well documented industrially. For example, in Canada, Pt is often associated with pyrrhotite but is not really processed as a straight pyrrhotite recovery.For the situation of Au and/or Pt associated with other base metal sulfide minerals, the industrial experience base is quite varied and is well documented from both North and South American operations. The nature of most of these flotation processes is to design, operate, and optimize the installed concentrator to get the Cu, Pb, Zn, Ni, etc. that is the bulk of the valuable sulfide ore and then take whatever precious metal recovery comes. Typically, such flotations are on the basic side using standard thiol collectors such as xanthates, dithiophosphates, thionocarbamates, etc. It is very common with such ores to use mixtures of collectors in order to get ""everything"". Often in such plants, there is an inherent balancing act occuring so as to operate in such a manner to reject pyrite (and pyrrhotite) in order to maintain high base metal mineral concentrate grades and yet recover sufficient precious metals such as Au and Pt minerals which often are associated with the iron sulfides being rejected. Obviously in such an environment, the smelter operation often ends up telling the concentrator what the precious metal recovery actually was in a given production period."

Jan 1, 1994

By I. Mc Dougall, H. Joubert, G. de Villiers

The use of sidewall copper cooling systems to prolong furnace campaign life is becoming an accepted technology solution in the base metals industry. Tenova Pyromet has designed and installed a number of sidewall copper cooling systems in base metals furnaces, including the platinum industry. Apart from increasing the furnace campaign life through the formation of a stable freeze lining, a well-designed copper cooling system enables the plant operator to focus more on optimizing the process to achieve throughput and recovery targets, and to accommodate more varied and available concentrate feed blends. The paper discusses the design of sidewall copper cooling systems for copper smelting and converting furnaces to achieve the above objectives. More specifically, the design of copper cooling systems for top submerged lance furnaces are discussed. An overall increase in furnace heat losses has been raised as a concern for intensively cooled sidewalls. The paper explores the overall heat loss expectations for copper cooled furnaces versus traditional refractory lined furnaces. In addition, the potential use of alternative cooling media is discussed. INTRODUCTION Base metal smelting and converting furnace technologies have been evolving continuously over the past century to satisfy the need for higher throughput, improved efficiency, and longer campaign life. To accommodate these demands, in particular higher smelting intensity and throughput, furnace bath containment systems had to improve. The use of pure refractory lining systems has slowly made room for the use of more intensively cooled lining systems (Joubert, Nikolic, Bakker & Mc Dougall, 2016). These cooling systems evolved from external shell cooling, such as shower or film cooling, to copper plate coolers extending into the furnace refractory lining, and high intensity stave or panel coolers (Verscheure, Kyllo, Filzwieser, Blanpain & Wollants, 2006). Consequently, an increasing number of base metal smelting and converting furnaces are equipped with copper cooling systems, including flash furnaces (Bryk, Ryselin, Honkasalo, & Malmstrom, 1958; Yasuda, Motomura & Kawasaki, 2014; Marx, Shapiro & Henning, 2010), top submerged lance primary smelting and fuming furnaces (Bhappu, Larson & Tunis, 1994; Kim, Lee & Lee, 2000; MacRae & Steinborn, 2018), top submerged lance converting furnaces (Viviers & Hines, 2005; Nikolic, Hogg & Voigt, 2018), primary platinum smelting electric furnaces (Nelson, Stober, Ndlovu, De Villiers & Wanblad, 2005; Jones, 2005; Hundermark, De Villiers & Ndlovu, 2006; Mc Dougall, 2013), and electric slag cleaning furnaces (Joubert, Nourse, Masters & Hundermark, 2005).

Jan 1, 2019

By A. Miura, R. Winarko, D. B. Dreisinger

Chalcopyrite leaching in acidic ferric sulfate media at ambient temperature exhibits slow kinetics and poor leaching efficiency, which is typically attributed to surface passivation. Recently, the presence of small amounts of iodide in the leaching media has been reported to significantly accelerate chalcopyrite dissolution. To further explore the behavior of chalcopyrite leaching in the presence of iodide, it is essential to determine the factors that control the leaching kinetics. In this study, we investigated the effect of initial solution potential, iodide concentration, particle size, and temperature on the kinetics of copper extraction from chalcopyrite. The key in the experimental setup was to minimize iodide loss by iodine evaporation and precipitation as cuprous iodide. The former was achieved by performing the leaching tests in fully sealed leaching systems. The latter was achieved by maintaining the solution potential higher than 420 mV (versus Ag/AgCl electrode), where formation of CuI precipitate is possible. The experimental results show that higher solution potential and higher iodide concentration had a pronounced positive effect on the rate of chalcopyrite dissolution. There was no effect associated with particle size, which might be due to the narrow size range tested. The positive effect of increasing temperature only manifested itself when the solution potential was sufficiently high. INTRODUCTION The main challenge of chalcopyrite leaching using ferric ions as the oxidant at ambient temperature is the slow kinetics and poor extraction. The reason for this leaching behavior has been attributed to passivation resulting from formation of insoluble passivating layers on chalcopyrite surfaces, which could be metal-deficient sulfides, elemental sulfur, polysulfides, and iron precipitates (Klauber, 2008). To overcome passivation, technologies using higher temperature and pressure have been developed to leach chalcopyrite concentrates, such as the CESL process (Mayhew, McCoy, Mean, & Woeller, 2013), FLSmidth Rapid Oxidative Leach (ROL) process (Mulligan et al., 2017), Galvanox (Dixon, Mayne, & Baxter, 2008), Albion process (Hourn, Turner, & Hourn, 2012), HydroCopper (Hyvärinen & Hämäläinen, 2005), TPOX (Dreisinger, 2006), and AAC/UBC process (Dreisinger, Dempsey, Steyl, Sole, & Gnoinski, 2003). Even though they are effective in accelerating copper leaching kinetics, those technologies typically have higher capital and operating costs associated with production of concentrates and application of autoclaves. This makes them unsuitable for treating low grade primary copper sulfide ores.

Jan 1, 2019

By Alireza Sarafi, Alijan Aftabi

"A hydrocyclic system used for mineral separation at the laboratory scale results in the separation of more than 90% of micas. The system functions only by water and might offer advantages where other methods of mica separation are not available. INTRODUCTIONVarious methods for the separation of micas, wollastonite, and garnet, e.g., screening, flotation, magnetic separation, and heavy liquids, are well known (e.g., Spence, 1929; Bates,I960; Gillson et al., 1960; Benjamin, 1971; Connor and Kolhnar, 1991; Collings and Andrews, 1991). However, where these methods are not available, the separation of micas by a hydrocyclic system developed by Sarafi and Aftabi (1991) may prove to be economic. This note is a brief description of the hydrocyclic system. Minerals and MethodFor testing the recovery of mica and other minerals from different rocks (garnet-mica schist, skarn, and pegmatite), standard minerals were tested first, and then rock samples. Pure mineral standards were prepared from coarse-grained samples of pegmatite, mica schist and skarn; the grain size of the minerals separated was more than I cm. The Hydrocyclic System and Mineral SeparationThe hydrocyclic system is shown schematically in Figure 1. In the first step in mineral separation, mineral and rock samples were crushed, milled, and then sieved to minus 250 plus 125 microns. Approximately 10 gm to 25 gm of the sample were inserted in decanter Dt • The motor pwnps, M1 and M2, were then turned on and the water valve rl was opened. At this time, water was flowing turbulently (30 em3/sec. to 50 em3/sec.) and minerals were separated according to their crystallographic nature, density and!or habit. The fInal separation was done by exit valves r2, r3 and r4, while the motor pwnps were still operating. After each experiment, the rt , r2' r3 and r4 valves were closed and the motor pumps were turned off. Following this, minerals in each decanter and the mter were collected, dried and weighed. The whole time of the experiment was optimized to be about 10 minutes, but varied from 3 to 15 minutes for micas and garnets. respectively."

Jan 1, 1994

By M. L. Goble

"Inco Metals Ltd. (Manitoba Division) operates a mining, milling, smelting and refining complex, 500 miles north of Winnipeg in central Manitoba. The Thompson Mill is presently operating at 12,000 S.T.P.D. on ore from both underground and open pit mines. The ore is treated in two separate milling and flotation circuits utilizing a common crushing system which is located inside the main mill building. The milling facility employs approximately 43 operating employees, 30 maintenance employees and 20 staff in supervisory or process development roles.In recent years an increasing awareness of the potential hazards of contaminants in the work place has made it mandatory that all employers maintain careful and accurate records of the work environment to which each employee has been exposed during his working career.The importance of this record keeping and general observation of the work place cannot be over emphasized. Proper monitoring of the work place provides an accurate and complete record of the contaminants and physical agents to which an employee is exposed during his work career. This can aid in studies which might be conducted in the future and can also be used as a basis for instituting improvements to the workplace."

Jan 1, 1980

By Donald A. Cranstone

Donald Cranstone holds B.Sc. (Honours) and M.Sc. degrees in Geology from the University of Manitoba and a Ph.D. in Economic Geology from Harvard University. He has worked as a mine geologist, a provincial geological survey geologist and as a senior exploration geologist. He joined what is now the Minerals and Metals Sector of Natural Resources Canada in 1971, where he has been a commodity specialist for gold, for copper and another 28 metals. He is a senior mineral economist, currently engaged in analysis of mineral exploration and discovery success in Canada and of the future of the Canadian mining industry. Abstract This paper examines the history of Canadian non-petroleum mineral production. The outlook over the next 25 years, for mining in Canada and in each province and territory, is reviewed. The outlook for mining in Canada and in most provinces/territories is favourable, but problems seem likely in a few jurisdictions unless new orebodies are brought into production. In terms of exploration potential, Canada consistently ranks among the top three countries in the world. Over the last eight years, Canada has consistently been second only to Australia as a destination for exploration investment. For the first time, Canada is ranked in terms of total mineral production, including coal and construction materials, relative to all the countries of the world including countries of the former communist bloc.

May 1, 2001

By T. H. Etsell, P. C. Holloway

The fly ash produced by oil sands operations in northern Alberta represents a large, high-grade, potential resource for vanadium production in Canada. After extensive batch testing at the University of Alberta, a conceptual process flowsheet for the recovery of vanadium from oil sands fly ash has been developed. The various unit operations for this process, including decarbonization, roasting, leaching, desilication, precipitation, salt recovery and byproduct recovery, are described. Processes for the recovery of molybdenum and ammonium chloride from waste streams from this process, are proposed, as are potential uses for the ash residue; these byproducts represent significant potential sources of secondary revenue while reducing the environmental impact from the process. A preliminary economic analysis for vanadium recovery from oil sands fly ash using this process is also included and several major economic factors influencing its commercialization are discussed.

Jan 1, 2004

By E. Fiset, T. Hennebel, F. Verbruggen, A. Prévoteau, K. Rabaey

Arsenic (As), bismuth (Bi) and antimony (Sb) are known to affect the quality of copper deposits in copper electrowinning operations. The codeposition of As was previously believed to occur only at current densities far exceeding the range of typical current densities for copper electrowinning. In this study, we investigate the copper electrodeposition on different pretreated stainless steel (SS) substrates from bleed electrolyte in galvanostatic mode at –45 mA/cm². Scanning electron microscopy (SEM) micrographs illustrate that during the initial phases of copper nucleation and growth, the current density was locally increased due to the pretreatments. It was reasoned that the codepostion of As could possibly occur in normal electrowinning conditions, but the risk can be substantially reduced by good SS substrate handling and maintenance practices. INTRODUCTION The presence of As, Bi and Sb is known to have a deleterious effect on the copper cathode quality in copper electrowinnings (Hiskey & Maeda, 2003; Hoffmann, 2004; Xiao, Cao, Shen, & Volinsky, 2012; Xiao, Cao, Mao, Shen, & Ren, 2014; Jafari et al., 2017). They are known to influence both the chemical and physical quality of the copper as they can contaminate the copper (Jafari et al., 2017) and affect the copper deposit structure (Hiskey & Maeda, 2003; Kim, Kim, & Chung, 2009), which contributes to a degraded market value of the copper (Tuddenham, 1984). The incorporation mechanisms of these impurities are believed to occur mainly through slime inclusion (F. Xiao et al, 2012) and electrolyte inclusion (Hiskey & Maeda, 2003). Other studies suggested that codeposition of these impurities is possible by their standard reduction potential being close to the one of copper (Xiao et al, 2014). Hiskey and Maeda (2003) investigated the copper electrodeposition on a copper electrode substrate in Cu electrolytes with a Cu, H2SO4, As, Bi, Sb composition representative for commercial copper tankhouses. The combination of voltammographic techniques and Auger electron spectroscopy showed that As was the first impurity to be electrodeposited from this electrolyte, yet at potentials where the limiting current density of the copper electrodeposition reaction is exceeded. The copper tankhouses usually operate at a current density ratio of 0.3 to the limiting current density in order to achieve tolerable copper quality deposits. The codeposition of As could be considered impossible in this current density condition. However, it is known that during the initial phases of electrodeposition on foreign substrates, a substantial part of the reaction proceeds by growth of individual nuclei where the current density is locally high and diffusion limited (Radisic, Ross, & Searson, 2006). Furthermore, it was observed that copper nucleation on TiO substrates occurred preferentially in the scratched oxide free areas which could serve as parts with high localized current densities (Chang, Choe, & Lee, 2005).

Jan 1, 2019

By Richard Morland

The Ekati Safety Guarantee is a conversation that has been taking place at Ekati for the last two years. It is a challenging, confronting, inspiring conversation which encourages people to see and pursue the possibility of guaranteeing that nobody who works at Ekati will be seriously injured or killed at work. The conversation takes us out of the normal, incremental approach to safety improvement; it takes us out of the world of striving, of seeking, of trying, and allows us to stand in, and be a stand for the future possibility of Zero Harm. It requires an unreasonable stand for, and commitment to, our own safety and the safety of our colleagues. A Powerful Conversation The safety guarantee began with conversations between executive team members and has been propagated regularly through the line through management meetings, pre-shift meetings, during workplace inspections, job safety observations, job and project planning, orientation and induction sessions, and when opportunities present themselves. This is a conversation that continues outside of Ekati with family, with government, with community members. It is a stand for safety as a value. The conversation about the safety guarantee is now pervasive at Ekati and forms part of a framework of initiatives that have led to sustained improvement in safety performance. During the last two years, the recordable injury frequency at Ekati has dropped to its lowest level in Ekati?s history. At the same time, job safety observations have increased from 500 per month to 4000 per month, whilst the overall number of people at Ekati has reduced by 30%. It has led to new ways of thinking about the conduct of operations. It influenced the 2008 upgrade of the Ekati process plant, resulting in the development and implementation of a crane lift protocol that eliminated injuries during over 100 lifts in two weeks, in an area of difficult geometry and with multiple entrances. It created space to successfully conduct a challenging commissioning period for the process plant crusher, during which time the machine was disassembled and reassembled several times, without incident or injury. No production pressure was permitted to interfere with this work, in line with our stated aim that we wanted everyone involved to guarantee that they would not be seriously injured or killed?our people had the space to do the work at a pace, and in a way, that guaranteed this outcome.

May 1, 2010

By D. Madsen, B. Salamondra, A. Moss, D. Etienne

"Raise mining at the Namew Lake Nickel Mine in Manitoba uses 3 m diameter bored raises driven at 45 to 50 degrees dip for stope access and drilling. These raises are developed within the orebody on 20 m centres to accommodate electric-hydraulic longhole jumbos and charging wagons. Critical elements of stope development include delineation of are contacts, control of deviation during raise development, optimal stope sequencing to permit a high extraction rate, drill anchorage installation, production drilling and blasting, and ground control. Procedures to deal with these elements are described, with emphasis on the geotechnical investigation for design of open stopes and pillars.Although mining with drilled raises does not have the flexibility to follow large variations in orebody dip, results to date indicate that it can be used successfully in the thicker ore zones. Thinner zones are currently mined using a modified Avoca method. Some flexibility to accommodate variations in orebody dip in thin are zones may be obtained by using alimack raise climbers to drive access raises, and carry longhole drills and charging equipment. Rock quality has been sufficiently good to maintain stable stope walls for full-height mining of primary stapes at 20 m strike length.IntroductionThe Namew nickel deposit is located 60 km south of Flin Flon, Manitoba. It is a moderately dipping (45 to 50 degrees) pipe-like ultramafic intrusion with a sulphide halo enrichment. The diluted recoverable ore reserves at January I, 1990 are 2.2 million tonnes grading 2.05% Ni and 0.7% Cu. The operation is a joint venture between Hudson Bay Mining and Smelting (60%) and Outokornpu Mines Ltd. of Toronto (40%). The mine is budgeted to produce 530 000 tonnes in 1990. The deposit was discovered in 1984 and mine development commenced in 1987.In the raise mining area, primary stopes will be filled with a high quality backfill consisting of cement and quarried limestone. Secondary stopes will be mined out between the primaries in the second pass of mining. The design extraction rate is 94% over all.The orebody above 120 level has an average mining width of 2.4 m, so is too narrow for raise mining. A modified form of Avoca stoping is used."

Jan 1, 1991

By Marcel M. Djivre

Electromagnetic wire rope testing is the only practical non-destructive method to evaluate the current condition of wire ropes in general, and in the mining industry in particular. The method has been successfully used worldwide for decades. In mining it has considerably improved the safety of operations. Yet, problems persist. In particular both the Loss-of-Metallic-Area (LMA) readings, as well as the Local Fault (LF) readings, as obtained by different instrument operators, were found to be unacceptably diverse. Consequently, large sums have been spent internationally, as well as in Canada, comparing a whole range of these instruments in an effort to rate their performance. The published results clearly confirmed operational experience, namely that the LMA and LF readings were, indeed, unacceptably diverse. Excellent pertinent conclusions were also published. In Canada the authors? conclusion was that while the divergence in the LF signal based results could, possibly, be attributed to both hardware and human-error related factors, the LMA signal related quantitative uncertainties were human-error related. Consequently, much attention was paid in Canada to developing novel control methods, namely computerized ones to replace the more error-prone analogue ones. In addition new sensor-heads were developed, both for portable as well as for permanent installation with remote control operations. While these efforts were of considerable benefit, the situation must again be carefully reviewed with very special reference to deep-level mining, now of immediate concern in Canada as well. In this paper the authors supply an overview of the results obtained by three of the four major international projects referred to previously. Relevant conclusions/comments are also restated. Moreover, specific recommendations are put forward as to how current problems might best be remedied.

May 1, 2004

By J. B. C. Wu, B. McKee

"Mining along with subsequent processing of the minerals often presents conditions where a wear- and/or corrosion-resistant alloy is needed to minimize downtime and maximize efficiency. This paper is intended to give an overview of the alloys that are currently being used, as well as those developed in recent years that could be used in the mining industry. Emphasis will be put on the iron-, nickel-,cobalt-based alloys and composites containing a variety of carbides. The characteristics, properties, product forms, and methods of application are presented. In addition, examples of the actual use of these wear-resistant materials are illustrated.IntroductionPreventing wear and corrosion is important in any industrial operations. In the mining industry, the process equipment typically suffers many different types of material degradation. Abrasion, impact, erosion, metal-to-metal wear and corrosion are typically encountered. Each situation requires different material characteristics to retard the degradation process. Therefore, it is essential to understand the characteristics of the materials and the effects of the alloying elements.There are four common classes of metallic materials for resisting wear and corrosion; namely, iron-based alloys, nickel-based alloys, cobalt-based alloys, and carbide-containing composites. Each class of material has its own characteristics. Depending on the chemical composition, the materials within each class can be vastly different in properties. In recent years, there have been materials developed in each of the four classes using the knowledge of the metallurgical principles and the effects of the alloying elements on the material degradation process.To use a wear-resistant alloy, it is also necessary to understand the available product forms and their application methods. Weld overlaying is a traditional way of using these alloys (Wu and Redman, 1994). In recent years, thermal spray is becoming popular. For applications where over-laying and spraying are impractical, solid components can be made by a variety of casting and powder metallurgy techniques. They can also be fabricated from the wrought products.To select a proper material for an application, it is important to understand not only the characteristics of the wear-resistant materials but also the degradation process. Due to the complexity of the processing environments, past experience is also helpful in making the decision on the material selection."

Jan 1, 1997

By R. G. Hamm

A brief outline covering the shovels and draglines in use in the open-pit mines of Western Canada, including British Columbia, Alberta and the Yukon, is given, followed by the procedure for the selection of the correct wire rope for each application. Such fa ctors as wire rope constructions, lay directions and types of cores are mentioned. Once the correct wire rope has been selected, there are variousfactors that can affect the service fife ofthe rope and the reduction ofdown-time during rope change-overs. Factors such as hairpin winding, types of Becket loops, and shovel drum and bail adaptors are described.

Jan 1, 1979