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By Ludwig M. Strah

"Wear is a universal problem and is present in all cases wherein one weighted surface moves with or relative to another surface. A practical description of wear as applied to mineral processing plants is outlined.With the advent of higher material and maintenance costs, more attention is being focused on the field of wear resistant linings. The aforementioned is magnified today as the production facilities continue to be designed to handle larger daily capacities. These changes, higher costs and larger plant handling facilities have necessitated the introduction of different materials and designs to combat the never ending battle against wear.In order that wear be understood, it can be relegated to two specific types:1 - Mechanical Wear - due to movement of one loaded surface relative to another.2 - Chemical Wear - more easily defined as corrosionMechanical wearMechanical wear can be subdivided into two basic forms:A.,Material movementB.,Material impactMaterial movement Abrasion is the result of, as earlier stated, the straight move¬ment of one loaded material relative to another.Material impact Is the striking effect when a mass strikes another from various angles and at various speeds. Impact can be severe enough to permanently damage and distort the basic component installed to overcome impact."

Jan 1, 1983

By M. Mirnezami, D. Lascelles, J. A. Finch, E. El-Ammouri

"Aggregation, i.e., the tendency of particles to cluster, can be expected to influence flotation selectivity. In this paper, a method of measuring aggregation is introduced and used to conduct plant surveys.Aggregation is measured using settling rate and turbidity converted to an aggregation index (AI) where 0 corresponds to most dispersed and 1 to most aggregated over the range of conditions tested, normally pH. Surveys of Cu and Zn flotation stages at four concentrators showed the AI increased significantly above pH 9. The metal ions identified in the process waters, principally Ca and Mg, were tested to determine which might be responsible. The presence of Mg was found to be the most important. In doping tests, Mg was shown to cause significant variation in AI over the pH range of 9 to 12.The impact of Mg was restricted to pH > 9. Over this pH range, Mg forms a range of hydroxy species, including Mg(OH)2 precipitates. An aggregation mechanism associated with these precipitates, electrostatic bridging, is suggested. Possible problems and opportunities in flotation practice arising from the findings are discussed."

Jan 1, 2002

By B. Simser

Noranda?s Brunswick mine is a 10 000 t/d producer of lead-zinc-copper-silver ore that has been in operation since 1964. Mining of this multiple lens deposit is primarily by blasthole stoping techniques between 400 m and 1200 m below surface. The combination of a high overall extraction ratio, an overall steeply dipping tabular shape, and high horizontal stresses (twice the vertical) have elevated the induced stress regime to levels comparable to much deeper operations. Improved mine design, and a better understanding of how the rock mass responds to mining in high-stress environments is essential to improve overall recoveries and maintain safety. Seismic monitoring has proven to be an essential tool at Brunswick, for both short-term safety of workers, and long-term strategic planning. Practical case studies illustrate how seismic data, particularly source parameter information, can be used to measure the rockmass response to mining and improve mining layouts in difficult regions. As the global trend continues toward mining in deeper, higher stress environments (e.g., South African Witswatersrand Basin, Sudbury Basin) and as local extraction and thus ground stresses continue to increase in existing deposits, seismic monitoring will play a critical role in mining safely and economically.

May 1, 2004

By B. Simser, V. Falmagne

"Noranda’s Brunswick mine is a 10 000 t/d producer of lead-zinc-copper-silver ore that has been in operation since 1964. Mining of this multiple lens deposit is primarily by blasthole stoping techniques between 400 m and 1200 m below surface. The combination of a high overall extraction ratio, an overall steeply dipping tabular shape, and high horizontal stresses (twice the vertical) have elevated the induced stress regime to levels comparable to much deeper operations. Improved mine design, and a better understanding of how the rock mass responds to mining in high-stress environments is essential to improve overall recoveries and maintain safety. Seismic monitoring has proven to be an essential tool at Brunswick, for both short-term safety of workers, and long-term strategic planning.Practical case studies illustrate how seismic data, particularly source parameter information, can be used to measure the rockmass response to mining and improve mining layouts in difficult regions. As the global trend continues toward mining in deeper, higher stress environments (e.g., South African Witswatersrand Basin, Sudbury Basin) and as local extraction and thus ground stresses continue to increase in existing deposits, seismic monitoring will play a critical role in mining safely and economically."

Jan 1, 2004

By L. D. Smith

"This paper examines the impact of the various assumptions that go into an economic evaluation, and shows how these can be combined to show an exciting result that may not really exist. An example of an embellished case (the kind that one frequently sees when projects are being promoted) is developed and the cumulative impact is analyzed to show the actual project underneath. The paper also points out some areas to watch for overly optimistic assumptions such as prices, inflation, and debt. The concept of a “bare bones” base case is proposed (constant metal prices, constant dollars, no inflation, no debt, no interest, on a project basis, after tax) as a common reference point.As well, the discount rate is examined as one of the fundamental means of reflecting risk in discounted cash flow evaluations. Current industry practice is discussed, and a methodology for the analysis of risk levels is proposed that assesses the constituent components of the discount rate: real interest, mineral project risks, and country risk."

Jan 1, 2002

By F. J. MacPherson, A. C. Caron

"Cassiar Asbestos Corporation Limited is at present B,C.'s only asbestos mining company, and has been actively engaged in the management and operation of the Cassiar Mine since the early 1950's. The Cassiar operations are located between 3,500' and 6,600' elevation in a secluded mountainous area of northern B.C., approximately 100 miles by road southwest of Watson Lake in the Yukon Territory. Climatic conditions in this area range from mild warm in the summer, to extremely cold during the long winter period.The minesite itself is located over a mile above sea level at the top of McDame Mountain, where year round 24 hours per day miners extract the chrysotile ore from the surrounding waste by standard open pit techniques. The ore body dips into the mountain at about a 45° angle, and as the mining progresses, larger stripping ratios are required. Waste to ore ratio this year will be more than 10 to l whereas only a few years ago ratios of 3 or 4 to l were possible. After drilling, blasting, and loading by shovel onto trucks, the asbestos ore is transported to the Primary Crushing Plant for crushing prior to transport by aerial tramway more than three miles to the Concentrator and Mill in the valley below, where the fibre is extracted from the barren host rock serpentine and milled into numerous grades for shipment to asbestos users round the world. The major air usage is associated with the milling process, presently requiring over 500,000 CFM, with future requirements expected to exceed 840,000 CFM by the end of the decade."

Jan 1, 1976

By Jamie Archibald

The Department of Mining Engineering at Queen?s University conducted a study of backfill practices in underground mines across Canada to assess the current state of backfill usage and to overview potential hazards associated with backfill practice, from preparation to transportation to placement. The primary aim of this study was to cover each component of a typical mine backfill system, and to identify potential incidents leading to the disruption of backfilling operations and any associated corrective actions. This paper, Part II of the study, deals with underground operations consisting of backfill transportation and backfill placement. Part I of the study, which deals with surface operations consisting of backfill material supply and backfill plant preparation, is also presented in these proceedings. A review of safety measures associated with current backfill operations and recommendations for procedures of best practice that should be implemented to reduce fill-related hazards in all mine backfill workplace environments are presented. In general it has been found that system failures normally lead only to minor losses to the operations.

May 1, 2009

By A. R. Miller, G. Desrivières, M. C. Bétournay, D. L. Barnes, P. Laliberté

"Over the last four years, an international initiative, championed by Vehicle Projects LLC, the Fuelcell Propulsion Institute and Natural Resources Canada, has been active in carrying out research projects to prove out the concept of applying fuel cell technology to underground mining vehicles. These have been carried out by a consortium consisting of mining companies, equipment manufacturers, technology developers, national laboratories and consultants, with the participation of Canadian and U.S. mine regulatory agencies.This clean technology, which produces only water and electricity, would allow several advantages to be obtained, in the health area (by eliminating diesel emissions and reducing noise generation), in lowering production costs (such as reducing ventilation required) and lowering greenhouse gas emissions.This paper outlines the results obtained in several key areas, such as, the operation of fuel cells in underground conditions, risk issues related to underground and surface operation of hydrogen vehicles and hydrogen production and delivery systems, and the design and mining performance of the world’s first hydrogen mining vehicle, a mine production locomotive. The work to date on the fuel cell loader, designing the power plant and power transmission systems, operational requirements, and operating cost reductions is also presented."

Jan 1, 2003

By P. N. Saavedra, E. A. Salamanca

"The maintenance strategies in the mining industry are changing from operative and periodic inspection strategies to a condition-based, predictive maintenance strategy centred in vibration analysis plus complementary techniques. Condition monitoring can also help to improve availability by being able to pinpoint and diagnose problems on operating machinery at an early stage. This reduces unscheduled downtime and production losses.However, in mining, for shovels operating in transient modes, with variable load and/or speed, the FFT (Fast Fourier Transform) standard approach is not directly applicable for analysis. This work illustrates how spectral order analysis and new transforms, called time-frequency transforms (TFT), allow us to monitor the shovel when it is working. Some practical examples showing the application of these analysis techniques to occasional vibrations measured on hoist and crowd transmission of a shovel are also presented. It is shown that at present, it is possible to carry out the vibration monitoring in the mining shovel while it is working, therefore avoiding the high cost of a loss of production which can occurr in traditional monitoring, where the measurement is taken while the shovel is out of production."

Jan 1, 2002

By C. Ketata, M. C. Rockwell

During the operation of a mineral processing plant, the unit processes are investigated by analyzing the data extracted by means of stream sampling. The data structure is identical to the time series form. Data analysis is a crucial step in understanding the plant performance. To control the plant performance efficiently, it is very important to avoid sampling errors, which is impossible. However, it is possible to minimize these errors. The factors influencing these errors are divided into two categories: material properties illustrating its heterogeneity, and sampler features. The purpose of this paper is to study the influence of the material composition variation on sampling errors, and to compare our evaluation method with that of Gy. Note that the stream mass flowrate is assumed to be constant during the sampling process.

Jan 1, 2001

By J. Lazareck

"XPotential Products Inc. has developed technologies to convert auto shredder residues and other forms of plastic waste into useful products such as posts suitable for retaining walls and parking curbs. The technology is competitive provided low-cost plastic waste is available, and could have applications throughout the world. The paper describes the technology used and illustrates the various processing steps. Development of the TechnologyPresently, state-of-the-art auto shredding yields approximately 75% ferrous and non-ferrous metals and approximately 25% by weight of auto shredder residue (ASR). Advances in metal shredding and non-ferrous metal separation technologies turned XPotential Products Inc.’s attention to ASR as a potential revenue source, or at least a means to markedly reduce the cost of disposal. This abundance of nuisance ASR was, in the company’s view, a potential resource as derelict autos and white goods were similarly perceived 40 years ago. As owners of General Scrap & Car Shredder Ltd. in western Canada, XPotential faced significant disposal costs for four shredders. This journey began over 10 years ago and took many twists and turns until a final course of action was chosen. The recovery of the metallic portion of vehicles and white goods has reached technological maturity and attempts to add value are now achievable only in very small increments."

Jan 1, 2004

By Richard C. Banting

Excessive vibration is known to have an adverse affect on soft body tissue and operators of heavy mining equipment can be exposed to vibration that exceeds levels recommended in international guidelines (ISO 2631-1, for example). Research has found that many of the seat and suspension systems currently used in mine haul trucks and load haul dump vehicles are actually amplifying the vibration. This overview presentation will outline the current research being conducted at Laurentian University and the University of Western Ontario, and the roles of partners in rating the ability of a number of commonly used mine vehicle seats to isolate harmful vibration.

Oct 1, 2010

By Pierre Gaucher

It is possible to selectively mine an orebody by combining the use of the SSW probe with any bulk mining methods as well as narrow vein exploitations. In other words, thanks to the use of the SSW probe, mining operators will be able to reduce and control dilution that is generally associated to every mining operation. Already, quick and substantial savings have been obtained. Falconbridge mines have demonstrated in Sudbury and Raglan operations, that the SSW probe can log nickel, copper and iron sulphides in blast holes. They have raised the grade and reduced dilution by outlining the limits of the ore zones before selectively loading explosives in the blast holes. By lowering the probe in a blast hole, a profile of the ore content is instantly measured and recorded. Logging cored diamond drill holes at the mine have demonstrated that the ore content (nickel, copper, cobalt, PGM) as assayed is proportional to the intensity of the probe?s electromagnetic response (EM), probably because the nickel / pyrrhotite ratio is uniform within a given orebody. The probe also measures the intrinsic conductivity of the sulphides and the percentage of magnetite. All probe readings are displayed and automatically stored at a 10-cm interval within the same reading unit. A 30-meter blast hole takes less than 2 minutes to survey. The whole instrument is light (12 kg) and very simple to use. One operator can carry the SSW system and survey either down or up-holes. The probe works from ?40°C to +50°C. Plotting the measurements of the SSW probe in blast holes (2-3-4-6-10 inches in diameter) before blasting allows to determine the exact shape of the orebody within the waste rock and uneconomic low-grade ore. Thus, only the portion of the holes that contains ore is blasted. The dilution is then much reduced and, by leaving the waste and low-grade ore in place, the mine saves on transportation, blasting, crushing, backfilling, milling, etc. Thousands of dollars are thus saved. Some savings may also be achieved during the development of stopes by guiding development drifts and by replacing diamond drilling by percussion drilling. In some circumstances, when the probe shows that some of the rich ore was not drilled-off, additional blast holes will allow to recover pockets of rich ore that otherwise would have been abandoned in the walls of a stope.

Oct 1, 2001

By David H. Searle

This paper will discuss the common trends existing in various Canadian jurisdictions for the closure and reclamation of mines. Included will be a discussion of the requirement to post security as well as its form and how security is calculated and refunded. Reclamation can no longer be left to the end of mine life. Progressive reclamation must occur throughout mine life and must be part of the mine plan from the beginning.

May 1, 2006

By Lauri Gregg

Key Message Energy focused Change Management Process that engages operations managers is the missing tool needed to build capacity for energy/GHG management

May 1, 2007

By Francis Chartrand

The Kwyjibo deposit is an iron oxide Cu-REE-F-Mo-Au mineralization of Mesoproterozoic age located in the Grenville Province approximately 120 km NE of Sept-Îles, Quebec (Figure 1). Occurring along the SE margin of the Canatiche granitic complex, the deposit is composed of several polymetallic showings that are related to different textural facies of magnetite. The mineralization process at Kwyjibo is complex, and is divided into Early Granitophile, Magnetite, Main Polymetallic and Specular Hematite stages (Cayer et al., submitted for publication). The Main Polymetallic stage, comprising chalcopyrite, pyrite, fluorite, molybdenite and REE-bearing minerals, is superimposed on pre-existing magnetiterich rocks. Discovered by SOQUEM Inc. in 1993, the Kwyjibo deposit shares many characteristics with other hydrothermal polymetallic iron oxide deposits around the world. Foose and McLelland (1995) suggested that this class of mineralization could occur in the Grenville Province. However, only a few polymetallic occurrences are known to be associated with low-Ti iron oxide deposits in the Grenville. Kwyjibo is one of the most significant examples of a polymetallic iron oxide deposit to have been found in the Grenville Province to-date.

May 1, 2003

By Alan D. Akerman

This paper describes the significant advantages and improvements in operational availability, reduced breakdowns, and overall cost reductions that can be achieved through the application of a Reliability Centred Maintenance (RCM) program, including Condition Based Maintenance (CBM) and Equipment Health Monitoring (EHM), in a mine environment. It uses a case study to illustrate the essential elements that constitute the basic requirements to establish such programs. This CBM case study analyzed the Load-Haul- Dump (LHD) vehicle sub-systems and their dominant failure modes, as a precursor to the development of condition indicators. The case study describes a disciplined process to enable condition indicator development and qualification in support of a CBM program. The identified condition indicators vary from readily applicable off-the-shelf monitoring systems and techniques, through to "leading edge" technologies that require further research and development. The paper also explores the developments that have been made in the combination of expert system software associated with modern computer based control systems, and the availability of "intelligent? sensor technology that complement the control system capability.

May 1, 2002

By Gorzalczynski. Stan

The recent trend in underground mine developments is ?big is better?. This is most certainly evident in the mine shaft and the conveyances that operate within its compartments. Today, there are several new installations requiring mine cages that can transport up to 170 passengers. The technology in mine hoisting is advancing to address a combination of higher capacity requirements, deeper hoisting depths and faster winding rates, however, some areas of the hoist plant have not changed for the past fifty years. The most notable of these areas is the shaft compartment guide string and the conveyance mounted safety arrest mechanism. The technology in use today for the protection of passengers in a shaft conveyance from a hoist rope severance incident, remains conceptually unchanged from Elisha Otis? design of 1850. The actual retardation components, the safety dogs, have taken on several forms since Elisha?s invention with the last major design change occurring in the late 1940?s. The arrest of a free falling shaft conveyance requires that the shaft guides withstand the energy imparted on them by the safety dogs. There are some very real limitations presented by the use of wood for this application. The new hoisting era will most certainly continue to demand larger capacity equipment but also, an increased awareness toward safety.

May 1, 2002

By Serge Ouellet

Résumé Six modèles métriques de remblai cimenté en pâte (RCP) ont été suivis durant 120 jours par l?utilisation de deux méthodes géophysiques non-destructives : la résistivité et la micro-sismique. Les RCP étaient constitués de trois résidus miniers et de deux proportions de ciment (3% et 6% en poids). En parallèle, des cylindres de RCP étaient utilisés pour évaluer périodiquement l?UCS. La résistivité augmentait quasi-linéairement de 28 à 120 jours pour tous les RCP investigués. Des variations de résistivité selon le type de résidu et le pourcentage de ciment ont été observées. Une équation empirique a été dégagée entre l?UCS, la résistivité, le temps, la densité relative et le rapport eau/ciment (E/C). La mesure de la vitesse des ondes de cisaillement a permis de dégager une équation mathématique de type exponentielle qui relie la résistance mécanique sans correction préalable par les paramètres de la recette de RCP. La réalisation de ce projet avait pour but de dégager la meilleure approche non-destructive afin d?estimer la résistance mécanique des remblais en chantier minier. Sur la base des résultats obtenus, les deux méthodes utilisées ont donné des résultats probants afin d?estimer la résistance mécanique et les deux méthodes sont donc à même d?être utilisées en chantier souterrain. Abstract Six scale models of cemented paste backfill (CPB) were followed during a 120 days period using two nondestructive geophysical methods: resistivity and micro-seismic. CPB were made up of three mine tailings and two cement proportion (3% and 6% by weight). In parallel, CPB cylinders were used to periodically evaluate uniaxial compressive strength (UCS). Resistivity was increasing nearly in straight line from day 28 to day 120 for all CPB models. According to the tailing type and cement percentage, resistivity variations were observed. An empirical equation emerged from UCS, resistivity, time, specific gravity of tailings and, water/cement ratio. The use of shearwave velocity allowed to identify a mathematical exponential equation related to mechanical strength without prior correction of the CPB?s formula parameters. The purpose of this project was to identify the best non-destructive approach in order to evaluate the mechanical strength of backfill in a mine site. On the basis of those results, both methods gave conclusive results in order to estimate mechanical strength and both methods can be used in underground operations.

Feb 1, 2008

Why Innovate in Mining? ?Obvious, right? ?Increase productivity and profitability ?Improve safety and ergonomics ?Improve our environmental record and eliminate liabilities ?Implement process control methodology ?Introduce information systems technology to gain control ?Low hanging fruit ?Reference ?Heather Ednie, Innovation CIM Magazine Feb. 2006 ?Peck & Skinner, Getting better bang for your buck with technology

May 1, 2006