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By D. W. I. Griffiths, J. C. Bélanger

"La Division Matagami de Minéraux Noranda inc. a profité de la construction de sa nouvelle mine (Isle-Dieu) pour continuer sa modernisation.L'utilisation d'automates programmables (PLC) s'est intensifiée pour contrôler et automatiser de plus en plus d'équipement dans ses minessouterraines, au concentrateur, dans les atelierset bureaux.Tous les PLC comrnuniquent entre eux et les IBM PC sont utilisespour exterioriser l'information et faire Ie lien entre Ie personnel et les automates. Le système Central IBM 36 emmagasine les donnees traitees par lesPLC (a travers les PC). Ces donnees sont transmisesau programme d'entretien de chaque equipement et compile les heures, cycles, tonnes, etc., fait imprimer automatiquement les feuilles d'entretien préventif ', etc.Les principales realisations adate et en progrès pour la mine Isle-Dieu sont:• automation complète du système de remblayage du concentrateur ala mine Isle-Dieu situee a2 km de la mine principale;• automation du fonctionnnement des ventilateurs qui comprendra la position des portes de ventilation, Ie chauffage, Ie débit, etc.;• automation des pompes, surveillance des sous stat ions électriques, concentration des gas (CO, SO2) à chaque niveau en tout temps et du propane à l'entree d'air frais;• tonnage et cycles par Ie treuil; et• contrôle d'autres équipernents à differénts niveaux. D'autres travaux furent egalement effectues par les employes, tels que:• la conversion d'un Scooptram ST5A de diesel à électrique;• I'installation complete de systèmes de depoussierage a I'eau (scrubber) pour le concassage secondaire;• I'installation d'un marteau hydraulique avant les concasseurs coniques;• la rénovation des cellules de flottation ; et• l'installation d'un système de gardiennage par caméra. D'autres projets seront effectués ou étudiés:• automation d'un Scooptram"";• automation d'un marteau hydraulique;• récupération de Scooptrarn; téléguidé:• gestion de l'énergie, contrôle de la demande, surveillance et contrôle de l'équipernent de machines fixes(compresseurs, boulloires, pompes à vide, génératrices, débits et pression d'air, eau pour diagnostiquer les problémes, analyser les coûts;• concasseur portatif pour fabriquer de la pierre concassée pour utiliser dans les chemins sous-terre, et• utilisation de micro-ondes pour transmettre les images captées par camera."

Jan 1, 1990

By L. Bichler, C. J. Verdon

In this work, the effect of doping yttria stabilized zirconia (YSZ) with 5, 10 and 15 mol% erbium oxide (Er2O3, erbia) was investigated using spark plasma sintering (SPS) technique. Sintering was carried out at 1300°C with 30 and 60MPa uniaxial pressures and a 5min hold time. Densification kinetics were studied using displacement response from the SPS machine. As-sintered microstructure characterization was carried out via scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques, while chemical composition was characterized by energy dispersive X-ray spectroscopy (EDS). The results suggest that sintering carried out at 60MPa produced high density composites even though erbia dopants were found to inhibit material densification and grain growth during sintering. 5, 10 and 15mol% erbia- YSZ had cubic crystal structures, as verified by XRD analysis.

Jan 1, 2014

By K. D. A. Whaley

The Captain North Extension deposit consists of five sulfide lenses hosted in cherty and chloritic metasediment that is bounded by quartz-eye rhyolite and laminated rhyolite. Lens 2 consists of sphalerite and galena with silver-rich tetrahedrite in chert. Lens 3 contains massive pyrite, with chalcopyrite and minor gold, gradational to minor pyrite in a chloritic metasediment. The other lenses are unexplored. The sulfides occur as beds, fracture infills, and disseminated grains. Reserves are estimated at 207 555 tonnes grading 7.380/0 Zn, 2.76% Pb, and 91.81 g/t Ag. The deposit is isoclinally folded, dips steeply west, plunges 50 degrees south, and is faulted out to the north, where drag folding has reversed the plunge. Minor cross-faults contain talc and sericite. High sphalerite but low pyrite abundances result in poor responses to standard electromagnetic techniques. Lens 3, which contains more pyrite than Lens 2, responds better to induced polarization and allows detection. Geochemical anomalies are found in a nearby swamp and stream, but an impervious till cover inhibits the development of soil anomalies.

Jan 1, 1992

By J .. A. Nemes, I. Ragai

This paper discusses one of the common problems associated with sheet metal forming processes, which is spring back. The materials presented here, stainless steel 410 and Inconel 718, are commonly used in aerospace applications for their superior material properties. Standard tensile tests were performed to determine their tensile properties, as well as material anisotropy. In addition, the effect of anisotropy on springback was assessed experimentally through simple multiple-bending experiments in different directions to the rolling direction. Finally, draw-bending experiments were carried out to study the effect of forming conditions, such as blank holding force, on the final springback angles of the formed parts. For both materials, it was found that the R-values measured for different sheets exhibited variation. However, the specimen orientation does not have a large effect on material tensile behavior or springback angle for simple bending. For the Inconel 718 specimens, the springback angle slightly increases with each stage of deformation during multiple bend experiments. The effect of the blank holding force on springback angles was also examined and found to have a significant effect on thin specimens.

Jan 1, 2006

By K. N. Karparov

?Two highwall failures in a South African coal mine defied analysis by widely accepted limit equilibrium methods. ?The geological conditions were complex, with undulating coal-bearing strata overlying a karstic topography formed in underlying dolomite belonging to the Transvaal Supergroup. ?It was clear that the simplifying assumptions made by all limit equilibrium methods were inappropriate in the conditions.

May 1, 2007

By Christopher H. Clement

The International Commission on Radiological Protection (ICRP) is an independent, international organization that advances for the public benefit the science of radiological protection, in particular by providing recommendations and guidance on all aspects of protection against ionizing radiation. This presentation touches on aspects of The 2007 Recommendations of the ICRP, a fundamental document that lays out the system of radiological protection for all exposure situations and types, and focuses on other recent publications relevant to the uranium industry. Of particular relevance are the 2009 ICRP Statement on Radon and the accompanying report on lung cancer risk from radon.

Aug 1, 2010

By O. Moselhi

The purpose of this research is to evaluate the impact of Building Information Modeling (BIM) on Just-In-Time (JIT) material delivery, with a focus on how the use of BIM can help improve efficient implementation of JIT and reduce the cost of material management. Previous research and a number of case studies have addressed the positive impact of BIM on construction at large but none focused on JIT in construction. This paper presents a methodology for selecting reliable material vendors. It also utilises the integration of BIM and scheduling software to generate quantities of material and its required delivery time to improve the flow process and improve its reliability to minimise related delays and productivity losses arising from idle and non-productive time of equipment and labour on jobsites. 4D visualization is utilized to support coordination and timing of JIT material deliveries in an effort to minimize congestion on job sites. Case studies on JIT material deliveries are presented and the impact of BIM implementation on reducing the cost of material management is evaluated. The joint effect of BIM and JIT on quality control, elimination of waste, reduction of inventory buffers, and on relationships with material vendors are evaluated by analysing and comparing data from case studies. The paper also presents a methodology based on multi-attribute decision criteria for modelling the selection criteria for material vendors. The model can assist in ranking vendors not only based on cost and quality but also on their reliability in delivering material on time.

Aug 1, 2013

By Michel Aubertin

Using mine wastes as backfilling material for underground stopes has been a common practice for more than 60 years. Waste rock and tailings are used as filling materials because they are available at a reasonable cost to support the rock walls. Backfilling is also very advantageous because it reduces the amount of mine waste disposal on the surface. In underground mines, the backfill must first ensure stability of the opening, while increasing recovery of ore and minimising dilution. It is thus critical to accurately evaluate the pressures exerted on the walls and on the barricades placed near the base of the stope. In this presentation, existing solutions for evaluating the stresses on stope walls and barricades are briefly reviewed. The authors then present recently developed analytical solutions that take into account the stress transfer from the backfill to the walls in the stope and access drift. The stress state solution, which is based on arching theory, considers the influence of the stope geometry and barricade position within the drift. The method gives the pressure generated by partly or fully submerged backfill. The solutions apply shortly after backfill deposition, when the effect of pore water pressure cannot be neglected, and also for long term conditions under a fully drained state. Experimental testing and numerical modelling results are used to validate the proposed equations. Both numerical and analytical results show that the total pressure on barricades can be significantly increased by water pressure, while the effective stress is decreased (compared to dry or drained conditions). A discussion follows on the implications of the results for backfill applications.

Nov 1, 2008

By J. W. Merks

"The accuracy of a measurement on minerals and ores can be assured by applying suitable and unbiased procedures but its precision is a function of the number of primary increments and their mass, the number of lots per consignment or samples per shift, and the number of measurements on analysis fine samples.Experimental data will be used to show how the variance components for sampling, sample preparation and analysis contribute to the total variance on which precision statements for the final measurement are based. This type of experiment should not only form part of quality control programs at mines and smelters, but also underly the criteria on which the design of manual sampling regimes and mechanical sampling systems for bulk solids and slurries should be based.Sampling systems and regimes can only be adjusted and optimized if the variance component for each step in a quality evaluation process is measured. Knowledge of precision characteristics lies at the core of effective loss prevention and control programs."

Jan 1, 1985

By F. R. Archibald

IN a recent paper on Roasting of Beattie Concentrate (1), the importance of controlling the temperature, and the sulphur dioxide concentration was pointed out. It is the purpose of the present paper to present further information by which the most satisfactory conditions for roasting are more specifically defined. Incidentally, a method of illustration is developed for representing roasting curves on a three-dimensional diagram. The primary purpose of this investigation, as in the case of the earlier work, was the search for information that would be of practical value in improving plant operation and gold recovery. For this reason, emphasis is laid on the regulation of essential variables and on definition of their optimum values and limits for maximum gold recovery in the subsequent cyanidation process. Good roasting is considered at least as much an art as it is a science, and, in this light, theoretical consideration of the nature and sequence of the chemical reactions involved is of secondary importance. The presentation which follows includes a series of graphical illustrations, an interpretation of the graphs, some theoretical considerations, and a description of laboratory technique.

Jan 1, 1940

By Marcel M. Djivre

The paper will outline historically the different materials used for pouring sockets and illustrate the current trend due to inherent advantages. A section will be devoted to engineering stress analysis showing the criteria necessary for the wires not to slip inside the poured socket material. The Ontario Mining Regulations pertaining to poured sockets will be reviewed with emphasis on the acceptable type of sockets depending on usage. In addition the paper will review the proper socket preparation techniques and explain the destructive testing conducted at the Materials Testing Lab essential for the certification requirements. In conclusion the paper will show the importance of the Certification Program for the safety of Miners working in Ontario, Canada and the World. The paper is also intended to inform the Mine Operators and Consultants that to-date the .Wirelock. sockets have been used safely for hoist ropes of locked coil and non-rotating construction and for the termination of balance ropes, and that further research is required on the construction of a socket approved for rotating type mine hoist ropes.

May 1, 2003

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 M. P. Amsden

"Ecstall Mining is a wholly-owned subsidiary of Texas Gulf Sulphur at Timmins, Ontario. The mill tonnage is 10,000 tons per day of two different ores, a copper zinc ore and a silver lead zinc ore, producing about 2400 tons of concentrates per day. These are as a copper concentrate, a high silver zinc concentrate, a low silver zinc concentrate and a silver-lead concentrate. For flotation recovery a very fine grind is required, about 80% minus 325 mesh and the concentrates produced are 40% minus 10 microns.The thickened concentrates are pumped to the filter floor for filtering and drying. The filtering and drying section is separated from the flotation section by a wall and is controlled from a dryer control room by one operator.Two operating panels are located in this control room. One contains stop-start controls for the thickeners, filter motors and vacuum pump motors, and stop-start controls for dryer feed conveyors and dryer product conveyors to concentrate load-out bins, as well as ammeters for conveyor drive motors. Dryer throughput is regulated by Merrick Type L weightometers located on the dryer discharge conveyors and recorded on tons per hour strip charts.The second panel contains the temperature strip charts, furnace drive ammeters, scrubber and exhaust gas controls, burner controls and panel alarms for the four dryers.Filtered concentrates are dried in Nichols-Herreshoff, multiple hearth, dryers consisting of nine hearths (zinc) and seven hearths (copper and lead). There are two dryers for handling zinc concentrates and one each for copper and lead concentrates. The dryers are heated by burning natural gas. Each zinc dryer handles 1,000 t.p.d. and the copper and lead dryers 750 t.p.d. each.Multiple hearth dryers are unusual in the base metal mining industry and the reasons for selecting them in preference to rotary dryers are as follows:1) The concentrates could only be filtered to 15 to 17 percent moisture. These sloppy filter cakes would be extremely difficult to handle in rotary dryers."

Jan 1, 1972

By M. Duncan

Lightweight, high-pressure cylinders for compressed hydrogen storage are essential components for fuel cell vehicles. Storage volume and mass are two key considerations. Current on-board hydrogen storage systems are based on a maximum pressure of 350 bar. While 350 bar systems are excellent solutions for many applications, some situations require higher storage densities due to space restrictions. As a result, significant research and development work has been expended by cylinder manufacturers, systems providers, testing agencies and automotive manufacturers to develop 700 bar systems with reduced storage volumes. Dynetek Industries Ltd. has proactively developed several 700 bar storage cylinders based on a seamless aluminum liner over wrapped with a carbon fiber composite. This paper presents the challenges and processes involved in the design, testing and certification for Dynetek Industries Ltd. 700 bar cylinders. This paper also provides reasoning for further volume and mass optimization of compressed hydrogen cylinders through the establishment of realistic cylinder usage parameters in standards. In particular, the overly conservative fill life requirement for cylinders is examined.

Jan 1, 2005

By R. Maxwell

"At Opemiska Copper Mines we have, over the past four years, operated 300 cu. ft. and 700 cu. ft. flotation cells as roughers, scavengers and cleaners and found them competitive with conventional flotation cells on a cu. ft. basis on all phases of flotation.The economics are very much in favour of the large cells for the following reasons:Power consumption is 35 to 40%, of conventional machinesMaintenance cost is about 20 to 25% of conventional machinesSpace required is about 30 to 35% of conventional machinesInstallect cost is about 40%, of conventional machinesTo put the above in more concrete terms below is what we are doing at Opemiska:1. Increasing mill capacity from 2000 to 3000 T.P.D. and will use only 5Cff, of the flotation space for 3000 tons that we used for 2000 T.P.D. with conventional flotation machines.2. Will require only 10 flotation cells for 3000 tons against 85 conventional cells for 2000 tons.3. Cells will be, one 2000 cu. ft. rougher, six 700 cu. ft. scavengers (2 banks of 3 each) and one cleaning circuit using three 300 cu. ft. cells.You will note that in this 3000 ton per day plant, we are going to have only ten cells. Had we put in conventional cells for this tonnage, we would have needed 120 cells."

Jan 1, 1970

By T. Krumins, L. Zunti, R. Frischmuth

Titanium and titanium alloys are commonly selected for pressure oxidation autoclave vent piping and pressure control valve components, as well as autoclave internals, in high-temperature operations. In a vent application, titanium ignition risk is reduced by limiting oxygen concentration, and preventing high gas velocity gas impingement on surfaces. Oxygen concentration is dependent on the autoclave pressure and temperature conditions and therefore titanium ignition risk is dependent on standard operating procedures, and process control interlocks and permissive conditions. It is not uncommon for standard controls to be deficient during atypical operating conditions, or for operations to deviate from the operating procedures, increasing the potential for titanium ignition incident. Titanium ignition risk caused by elevated oxygen concentration in autoclave vent systems can be reduced with the introduction of an online autoclave overpressure calculation and the configuration of associated interlocks and permissive conditions.

Jan 1, 2014

By Roy Sage

Overview ? History ? background to current programs ? Kyoto status ? Support for technology development ? Support for GHG reduction ? Sources of information History ? 1988 - Toronto Conference - The Changing Atmosphere ? Proposed target ? CO2 levels reduced to 20% of 1988 levels by the year 2005 ? 1992 - Canada signed Framework Convention on Climate Change at the UN Conference on Environment and Development in Rio de Janeiro in June 1992 ? Canada launched the National Action Plan on Climate Change ? Kyoto protocol adopted in principle in 1997

Nov 1, 2002

By A. Kozlowski

We present research on cable fault location methods for mines where coal dust and methane explosions are a frequent potential hazard. The methodology and devices for low- and medium voltage cables fault location are well known and applied in classical power distribution networks. They are based on solutions for underground mines with a high risk of explosion. The lack of a safe solution for the location of a fault has contributed to the initiation of a research project by a group of Polish companies. The consortium consists of research institutes (Institute of Innovative Technologies EMAG, Tele and Radio Research Institute, Central Mining Institute GIG-KD ?Barbara?), Silesian University of Technology and a private entrepreneur MARTECH PLUS. Fast and exact determination of fault location is one of the important factors for minimizing power outage time. The lack of technical solutions to obtain measurements in a secure way leads to the use of the methods connected with a high risk of explosion. For example, the application of high energy can lead to arc discharge where there is a fault in insulation, creating the risk of an explosion. Measurements of methane concentration along the analyzed section of the cable reduce the risk; however the shock wave generated by the electric arc may raise coal dust and make an explosive mixture, which is an object of ignition. Low energy methods, like those based on reflection waves, have low sensitivity for high- and medium-resistance faults. This technique has difficulties in joints, which create false echoes. The fundamental problem is to determine the topology of the network using a reflectogram and find anomalies of a different nature ? not only open and short circuit. Included in the scope of the project is an analysis of Polish legal regulations related to fault location and operational work for low- and medium-voltage networks. Two of the methods used on the surface were selected as feasible to implement under explosion hazard conditions. In the process of development of the fault location methodology, installation features characteristic of underground mines were used, namely access to the whole length of a cable. This is the attribute that provides an opportunity to do measurements that are usually not possible for typical surface power nets. To carry out laboratory tests, a dedicated measuring stand with various types of cables was built. The authors describe the principle of operation of the fault locator and the results of the laboratory tests carried out on the cables with built-in damage (prepared for tests). Results of the work will be the basis for the next stage of the project associated with operational analyses of the prototype.

Aug 1, 2013

By J. E. Nesset

"As an alternative to conventional dewatering by vacuum filtration and oil-fired rotary dryers, Brunswick Mining conducted extensive pilot-scale testwork on its copper, lead, zinc and bulk concentrates using a Larox Oy (Finland) automatic pressure filter. The results showed that pressure filtration readily produced final cake moistures of 6-8.5 per cent on this very fine sulphide material.An in-depth analysis examines pressure filtration in terms of metallurgical performance and projects energy savings of 78 per cent for pressure filters over the current dewatering operation. Potential energy and operating cost reductions are also estimated.IntroductionVacuum filters followed by oil-fired rotary dryers are one of the most common means of dewatering mineral concentrates. They represent, however, a level of technology which is exceedingly wasteful in terms of manpower, space utilization equipment and fossil fuel dependence. In addition, the use of thermal dryers is leading to increased environmental concerns both in plant and out.These were the primary factors which prompted Brunswick Mining to consider alternative dewatering methods as the existing equipment came up for replacement and upgrading. In late 1979, company engineers were encouraged by automatic Larox pressure filters seen at several Scandinavian operations. Subsequent laboratory tests by the manufacturer (Larox Oy of Finland) on several concentrate samples were sufficiently promising for Brunswick and Noranda to lease a trailer mounted filter-lab unit and a technician from Larox for a five-week period. Extensive on-site testwork on all four Brunswick concentrates (zinc, lead, copper and 'bulk' lead-zinc) confirmed the potential of pressure filtration."

Jan 1, 1982

By Kathy Pomeroy

Sharing?? l Maybe not the first image that comes to mind when we think about the historical corporate mind set and track record of many corporations ? ! A Fundamental Change in Relationships l From a worldview of independence to one of recognized interdependence l Collaborative action with communities for long range mutual goals l Acceptance of greater accountability for the whole l Community and government relationships based on trust, mutuality, respect for human rights, equity, sustainable agreements

May 1, 2002