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By Frank Lemy

This paper presents an application of digital face mapping in an underground mine. Based on photographs it was possible to construct discontinuity maps, which were used to characterise the rock mass. The results were compared favourably with values obtained through scanline and area sampling mapping for the same site. The case is made for digital mapping as a safe, fast, and efficient way to characterise rock mass structure for engineering purposes.

May 1, 2001

By T. Billotte, G. Tirand, J. Zollinger, V. Robin, B. Rouat, D. Daloz

The grain structure prediction of metallic alloys during a welding process is often an issue. In addition to the welding parameters and the alloy nominal composition and properties, the base metal grain structure and chemical homogeneity also play an important role in the formation of the final microstructure. In this paper intensive characterisation of solidification structure in gas tungsten arc welding of Ni base alloy 600 are described. It is shown that in transverse section of the weld, while the grain structure shows some texture following constrained solidification growth, grain density in the weld is similar or greater than grain density in the heat affected zone. This suggests that simulation of the welding structure needs, in order to be predictive, to take into account : epitaxial growth, secondary nucleation events and 3D growth inside the weld pool.

Jan 1, 2015

By Marcel Vallee, Fernand Dubuc

"The St-Honoré carbonatite complex, located 8 miles north of Chicoutimi, Quebec, was discovered in September 1967 as abnormal radioactivity was detected in the course of SOQUEM's aerial surveys. The complex, covered by a shallow layer of Trenton limestone, has been explored by aeromagnetic, ground gravimetric and magnetic surveys, and 12,013 feet of diamond drilling. Its age, from potassium-argon dating, is 650 million years. The carbonatite is approximately kidney-shaped and has a surface area of 6 square miles, 20 per cent of which is explored. It shows a central core of coarse-grained massive dolomitic carbonatite and an outer ring of foliated dolomitic carbonatite.The exploration work to date has resulted in the discovery, in the foliated carbonatite, of an incompletely drilled niobium (columbium) zone of pyrochlore-bearing carbonatite, at least 1,000 by 800 feet in size. This zone contains 5,000 tons per vertical foot grading 0.86 per cent Nb205 or at least 15,000 tons per vertical foot grading 0.66 per cent Nb205 or 45,000 tons grading 0.48 per cent Nb20s. The pyrochlore contains an average of 64 per cent Nb,Os. The central core contains a zone of rare-earth-bearing carbonatite (as monazite), grading up to 4.5 per cent rare-earth oxide, 3,500 ppm zinc and 290 ppm molybdenum. Stocks of nepheline syenite and magnetite diorite accompany the carbonatite. The total analysis and trace-element contents of typical rocks are presented."

Jan 1, 1970

By J. W. Merks

"Simulation is the process of designing a computerized model, of a system or procedure, for the purpose of understanding its behaviour and developing strategies to control its operation. Simulation models are rapidly becoming an effective tool for mineral processing plants. Powerful software and fast hardware are more readily available than a basic understanding of the theory of mathematical probability and applied statistics that process simulation models demand.Simple spreadsheet software can be used to develop simulation models that take into account any set of conditions at a mineral processing plant. In addition to an unbiased estimate for each variable in the set on which two-and three-product formulas are based, reliable variance estimates for all variables are required. How to estimate variances, effectively and at the lowest possible cost, and how to compute variances for simple functions such as the metal content of a quantity of ore or concentrate, or more complex functions such as the percentage recovery at a mineral processing plant, are the key to useful simulation models.IntroductionSimulation models for systems and procedures have become one of the most powerful and effective applications for computers( 2.6). Simulations are applied to a wide range of scientific and engineering disciplines. Generally, a model is designed to investigate the effects of changes in and interactions between a set of variables before a system is in operation or a procedure is implemented, by simulating weeks, months, and even years of operation, in a few minutes of computer time. Along with practical and useful applications always comeabuse and misuse. For a simulation process cannot be more reliable than the methodology that was applied to design the model, to estimate variables and variances, to check performance, and to verify validity. A mineral processing plant is a dynamic system that changes continuously as a function of time but within probabilistic constraints that can be estimated by applying statistical tools and techniques to the variables and variances that interact in the system.A model should be designed to simulate not only the set of variables but also the variance for each variable. Models in which constant variances are used to generate normally distributed random numbers, are less realistic than models in which the variances are simulated first, and then used to simulate the variables."

Jan 1, 1991

By G. A. Gamble

"The inlet air velocity profile of any surface mine ventilation fan is an important factor when designing the connecting ductwork from the mine shaft collar to the fan. Deficient fan performance can be the result of ductwork that adds unnecessary pressure loss and/or adversely influences the fan inlet air conditions (velocity profile). The need for optimized inlet air conditions begins with discussing the process of performance testing during the development of the fan performance curve. Additional discussions include design of the shaft collar connection and the connecting ductwork. A preferred design of ductwork for parallel fan installations will be illustrated.INTRODUCTIONThe inlet air velocity profile of any surface installed mine ventilation fan is one of the most important factors to consider when designing the connecting ductwork from the mine shaft collar to the fan. Oftentimes deficient fan performance can be traced to poorly designed ductwork that adds unnecessary pressure loss and/or adversely influences the fan inlet air conditions (velocity profile). Such designs may lead to added power requirement, excessive vibration and noise, and reduced fan performance.Understanding the need for optimized inlet air conditions begins with discussing the process utilized when factory testing takes place during the development of the fan performance curve.Additional discussions include design considerations for the shaft collar connection, the connecting ductwork, and fan inlet. Illustrations of cost savings and pressure losses will be included for audience consideration. The design of ductwork for parallel fan installations on the surface is another issue that requires consideration. A preferred method will be illustrated.The selection of accessory components, such as self-closing doors, can also add to the potential for reduced fan performance. Several components will be discussed.An elementary presentation of the Air Movement and Control Association (AMCA) Standard 201 “Fans and Systems” will be included to provide background for those audience members that want additional technical explanations of the need for a uniform inlet air velocity profile at the fan inlet."

Jan 1, 2019

By Michael W. Russnak

Productivity and operating expenses are everything when it comes to judging how well your mine and company are doing. Stakeholders are always looking at these numbers and trying to understand if productivity is improving, if operating costs are trending downward and what you are basing your decisions on. o make improvements you first need to understand how you are performing. If you can?t get this basic information, you will never improve. You will not be able to make simple decisions related to maintenance, operations or production. Forget about planning, as you will only be guessing based on the numbers some stakeholder or your executive wants to see. The problem miners run into is not that the data doesn?t exist; it does, but typically it?s raw, it?s everywhere and its volume is huge. Today there is more on-board computing capability in shovels than we had on our desktops three years ago. Add other mobile equipment, plant systems and multiple OEM vendors to the equation and the challenge is daunting.

May 1, 2007

By G. A. Vissac

IN THE preliminary design of a coal washery, the most important factor to evaluate is the ash content of the final product. The ash content permissible may be imposed by market demands, but, in the final analysis, sooner or later - as most consumers today are buying coal on a 'heat value' basis - the coal operator has a certain margin of latitude. and the ash content of the coal to be delivered can be determined on the basis of maximum returns and highest profits. A few years ago, the most desirable separation was selected on the basis of the plus-minus 0.10; that is, the most desirable gravity of the separation was selected at the point showing a minimum amount of near gravities in the raw coal. The reason for this was an expected wide error over these near gravities. Today with the recent development of cry accurate, automatically controlled cleaning apparatus, a much larger latitude is possible, and the most desirable gravity of separation can be selected, almost exclusively, on the basis of the economic factors involved. To illustrate these new methods of investigation we shall give two examples, based on actual coals from the western United States.

Jan 1, 1957

By Ron Light, Doug Applett

"HistoryThe Nanisivik mine began operation in October 1976 as the world's most northerly metal mine and the first permanent industrial project in the Canadian High Arctic. Located 700 km north of the Arctic Circle on Baffin Island's Strathcona Sound, exploration by Texasgulf Inc. between 1957 and 1970 had outlined the ore deposit. In 1974, Nanisivik Mines Ltd. was formed with Mineral Resources International, the Government of Canada, Metallgesellschaft and Billiton being shareholders, and Strathcona Mineral Services Ltd. providing project management. In 1996, Breakwater Resources purchased the mine from Alberta Energy Corporation Limited which had recently acquired the assets of then owners Conwest Exploration Ltd.Ore DepositThe main ore deposit is very flat, approximately 80 m in width and varying in thickness from 3 m to 16 m. The length of the deposit is approximately 3000 m with satellite zones located on the perimeter of the main zone. The economic mineralization is sphalerite with minor galena and silver. The sphalerite and galena are coarse grained and associated with pyrite as the main gangue component with minor inclusions pf dolomite and calcite within the deposit. The deposit being hosted in a permafi·ost environment creates a number of challenges. Dry drilling is employed in room and pillar production drilling. The permafrost aids in the stability of both the pillars and the back."

Jan 1, 2000

By J. Chenier, M. Boissoneault, D. Ducharme, R. Schonewille

The operation of Falconbridge's Sudbury nickel smelter has undergone significant change since the production was consolidated to a single electric furnace in 1994. In the late 1990's a capital program of about $100 MM (Cdn) was undertaken to expand and modernize the smelter. This project, known as Smelter 2000, was mainly driven by the need to process the new concentrate produced at Falconbridge's Raglan operation in northern Quebec. Included in the scope of the project was the installation of dry concentrate handling facilities, modifications to the roaster feed preparation system, installation of a matte granulation system and modification of one of the converters. Improvements to in-plant hygiene were also an important part of the Smelter 2000 project. Over the past 5 years much has been learned about the challenges in treating two significantly different concentrates. More recently, the introduction of a third concentrate from Falconbridge's new Montcalm operation near Timmins, Ontario has added another dimension to the operation. This paper will describe how the main challenges from the past 7 years have been overcome and discuss the path forward for the Sudbury Smelter Business Unit.

Jan 1, 2005

By R. H. Chambers, L. Alderman

"The paper is introduced by an examination of the factors which have led to the present world-wide interest in charging preheated coal to coke ovens. Various possible methods of preheating and charging the coal are considered and reasons are given for the adoption of the methods chosen. The design of the pilot preheating plant for the British Coke Research Association is discussed and its influence on the design of the commercial units for the South African Iron and Steel Corporation's plant at Pretoria and the British Steel Corporation's plant at Beighton are explained. Operating procedures on the pilot plant are described, particularly with regard to the charging of the preheated coal. Design features of the commercial installations, engineered by Simon-Carves Ltd., are explained with emphasis on the built-in safety of the control system of the preheating plant, and the particular problems associated with the erection of such plants on working coke oven batteries. Commissioning and operating procedures are described and the problems associated with the integration of the preheating plant into the normal pushing schedule of the plant are discussed. Preliminary operating results with regard to the effect of preheating on coal throughput on the commercial plants and on the properties of the coke produced are given."

Jan 1, 1972

By B. W. Williams

The crack propagation behaviour of Zr-2.5Nb pressure tube material was studied through comparison of the measured behaviour with the predicted response from finite element analysis. Three-dimensional finite element simulations of compact tension specimens were performed using the crack tip opening angle as a fracture criterion to allow for crack propagation. To obtain reasonable agreement with the measured behaviour, it was important to capture both the anisotropic plastic deformation behaviour of the Zr-2.5Nb material through use of the Hill-48 yield criterion and damage due to void growth, nucleation, and coalescence through the use of a Gurson-based constitutive model in the simulations.

Jan 1, 2010

By M. Djivre, T. Eger, A. Godwin, I. Bhattacherya

Load-haul-dump vehicles (LHDs) are extensively used in underground mining, however, equipment design and operating conditions contribute to restricted operator sight lines. The inability to clearly see people, objects, or hazards around the machine has contributed to a number of accidents including fatal injuries. In order to identify vehicle design characteristics resulting in restricted and blocked sightlines, line-of-sight assessments are traditionally completed in the field. However, field methods are unable to evaluate lineof- sight under dynamic operating conditions, and are limited in their ability to provide feedback on the impact of various operator characteristics such as sitting height. Results of this research show computer simulation and virtual reality can be successfully used to evaluate line-of-sight during the operation of LHD vehicles. In order to benefit from virtual reality applications, the work environment, LHD vehicle, and human posture need to be represented as accurately as possible. A computer simulation program with ergonomic analysis features, Classic JACK 3.1, was successfully used. Threedimensional CAD models of LHDs were developed from manufacturer specifications and pictures taken from LHDs currently in use. The LHD models were imported into the JACK environment, a digital human was positioned in the cab of the LHD vehicle, and the vehicle and human were driven over a typical mine route. Real-time feedback in the JACK program was used to identify what the operator could see under different operating conditions. Machine characteristics and operating scenarios resulting in impaired line-of-sight were successfully identified with this method. The JACK program could also provide real-time feedback on the human’s joint forces and torques, strength requirements, postural comfort, and metabolic energy expenditure. As a result, this method could be used to successfully evaluate musculoskeletal injury risk factors along with system design recommendations to improve workplace safety and productivity in any setting. The LHDs evaluated in the JACK software package can also be combined with mine models and imported into other VR software packages (e.g. Blender) in order to enable viewing in Laurentian University’s Virtual Reality Laboratory. The VR models using these packages can be viewed in stereo to provide better appreciation of spatial vision issues.

Jan 1, 2005

By The Staff

Development of the Eldorado Mine THE pitchblende-silver deposits of Great Bear lake, Northwest Territories, were discovered by Gilbert LaBine in 1930. The property owned by Eldorado Gold Mines, Limited, consists of 53 claims situated, for the most part, on LaBine point, on the northeast shore of the lake. The Company also holds a group of 10 claims on Dowdell point, 7 miles to the southeast of the main group and across Echo bay. The fractures traversing the ridge on LaBine point can be readily seen from the air. Lack of overburden and the scantiness of vegetation leave rock exposures which are visible for miles. The years 1931 and 1932 were spent largely in staking, prospecting, and examination of the outcrops. A small Diesel plant was shipped to the property in 1932 and underground operations were started. Entry was made into the ore-body by means of an adit. A 20-ton mill was completed in the winter of 1933-34, and since then operations have been continuous, except for temporary shut-downs for additions to the mill. TRANSPORTATION The mine is situated 28 miles south of the Arctic Circle and is reached by an air route of 1,140 miles from Edmonton. The water route follows the course of the Mackenzie River system from Waterways, Alberta, the end of steel, and is approximately 1,450 miles in length. Two portages, at Fort Smith and on the Bear river, respectively, are necessitated by the occurrence of fast water. Transportation was one of the major problems to be solved, and Eldorado Gold Mines, Limited, found it necessary to embark upon both water and air freighting on its own account. The Company now operates a Bellanca 'plane with a payload of 4,400 pounds, and a complete water transportation system. The latter was established some years ago by the Northern Transportation Company and it is still operated under that name, but the Company is now a subsidiary of Eldorado. Modern steel boats, oil tankers, and barges were added to the fleet this season. The greater part of the ore shipments are made by water, aircraft being used for this purpose only when occasion demands. Freight rates have been greatly reduced by direct ownership of carriers. For example, water-borne freight is now quoted 'to the mine at $ll0 per ton, as compared with $240 per tan four years ago.

Jan 1, 1938

By Xiang Li, Xibing Li

It is paramount that the stability of rock slopes be correctly accounted for under diverse operating and environmental conditions. Owing to different sources of uncertainty entailed in such stability problems, conventional deterministic approach through the calculation of a factor of safety (FOS) cannot reflect quantified uncertainties explicitly and sufficiently. Thus it is highly desirable to invoke the reliability approach to consider uncertainties in a systematic manner. Nowadays, the current design standards have an increasing tendency to ensure rock slope stability by pre-defining a target reliability index (or target probability of failure), viz., the reliability level of a rock slope is pre-set as a target to be satisfied. In such a situation and considering the fact that the FOS used as an indicator of slope performance still has a very wide acceptance, we focus on proposing an inverse-reliability-based methodology which aims at developing a two-fold indicator strategy, i.e., using the FOS and reliability together to deal with slope stability problems. The basic idea behind it is to utilize a so-called inverse first-order reliability method (IFORM) to directly calibrate the FOS provided the target reliability index has been given. In this way, the calibration scheme relating the FOS can be rationally done by not only incorporating uncertainties, but also satisfying a desired level of the prescribed reliability. Based on this, to make the IFORM computationally feasible and also reduce its computational cost, we introduce the response surface method (RSM) to generate a surrogate for the FOS-based limit state function (LSF), considering the lengthy and complicated form of the FOS in some recognized methods (e.g., within the framework of limit equilibrium). Distinguished from the existing RSMs that potential inadequacies may arise, we present an RSM based on a hybrid approach combining support vector machine (SVM; used as a regression technique) and uniform design (UD; pertaining to experimental design). Using a representative example of rock slope stability problem, we demonstrate the feasibility and validity of the developed methodology, during which the associated sensitivity study and further discussion are also performed. By dint of such a methodology, we can establish a link between the conventional deterministic approach and the reliability approach, where a logical and realistic framework is provided, for cases achieving the specified reliability, to assist in selecting the FOS which remains adequate for rock slope stability even in the face of uncertainty.

Jan 1, 2015

This paper outlines the position and capabilities of Western Canada's bituminous coal industry, and indicates the increasing importance of Japan as an export market. The use of coal in Japan is reviewed, especially as regards future trends, and an appraisal is made of Canadian coal in comparison with domestic Japanese coal and imports from other countries. The importance of maintaining a solid nucleous within the Canadian bituminous coal industry is emphasized. I N RECENT years, Japan has emerged as a valuable market for Canadian exports. The first major product exported in volume to Japan was wheat, which has become very successfully established in Japanese markets. Following this, iron ore gradually found a market in Japan, with exports usually based on long-term contracts. This iron ore was produced entirely in British Columbia In 1958, the Western Canadian bituminous coal industry -jointly with the Dominion Coal Board -sent an official mission to Japan to investigate the

Jan 1, 1964

By Dave Shook

A Mineral Processing facility in Montreal has recently implemented a leading-edge intranet solution for monitoring the performance of plant operations, and providing condition-based maintenance. This innovative multi-faceted software implementation incorporates: web-delivered plant information systems; area-wide control loop performance assessment (using sophisticated algorithms to evaluate poorly performing controllers); and integrated alarm management functions. The system has enabled a project to improve plant operations through better process control. Maintenance technicians, engineers, supervisors and managers all can see the performance of the controllers, and the performance of the plant itself, through webdelivered graphics and reports. Information is combined from many sources, real-time, historical, relational and analytical, to provide a complete picture of plant operation. The web-based solution centralizes the administration of user access, and simplifies the deployment of several different kinds of information to many desktops. It is an extensible system that allows users to create and share their own web pages and data views. The paper will discuss the solution architecture and the improvements the I.T., operations, maintenance, and engineering groups have experienced, and overall benefits to the facility.

May 1, 2002

By S. Averill, B. Schreiner, V. Sopuck

The La Ronge. Kisseynew, Glennie Lake and Flin Flon domains. the main focu for gold exploration in the southeast part of the Saskatchewan Shield, were subject to continental glacial ice advances from the northeast during the Quaternary. Based on forty-four auger hole along with surficial mapping, the general Quaternary stratigraphy in this area is observed to be composed of a lower till unit , an overlying stratified unit of glaciofluvial sand and gravel and/or a glaciolacustrine silt-clay unit. an upper till. and an upper tratified unit. The lower till is commonly found throughout the geological domains except where it has been eroded in glaciofluvial or fluvial channels. Glacial Lake Agassiz fo rmerly covered most of these prospective domains. The lacustrine deposits associated with the lake impede surficial geochemical surveys including soil. lake sediment. and biogeochemical surveys. The approximate extent of clay cover can be predicted from beach elevations. For instance. in the Waddy Lake area. clay i not known to occur above about 1,400 feet (425 m) elevation. Exploration techniques are hampered by clay in at least one third of the volcanic belt. Thi s influence is indicated by the fact that nearly all gold prospect found to date are located above 1,400 feet (425 m) while the area of clay cover is vi rtually unexplored. The upper till i related to a minor ice readvance. This till is the medium often sampled during soil surveys in the area . lts value as a geochemical ampling medium is dependent on the extent of erosional contact with bedrock highs on the lower till. Those areas which are relatively free of lacustrine and fluvial deposits are those where surface geochemical methods work best. In the Waddy Lake volcanic belt approximately 25-50% of the area may be suitable for surficial surveys. The area of the Star Lake prospect occurs above the 1,500 foot (460 m) elevation and was not covered by Lake Agas iz. The effectivene of till sampling as a surface sampling medium was tested in those areas above the clay level. Till orientat ion surveys were carried out at the Star Lake property and the Tower Lake prospect (Waddy Lake area) within the La Ronge Domain . Gold grain counts and analy es of heavy mineral concent rate from 7 kg surface ti ll samples were used to delineate dispersion trains down-ice from mineralization. In addition, the clay fraction and a 30 g (-80 mesh) subsample from the same till sample, were analyzed for gold . In the Star Lake area, ice direction is subparallel to the strike of several narrow northeast trending auriferous structures. arrow dispersion trains down-ice from known

Jan 1, 1986

By Robert S. Penczak

Red Lake Gold Deposits ? Descriptive Classification (modified from Pirie, 1982) VHR Au -- Volcanic-hosted (vein & wall-rock) replacement Au deposits ~93% of camp production Q-(T) Au -- Quartz-(tourmaline) vein Au deposits ~7% of camp production Quartz-sulphide Au deposits Porphyry-hosted sulphide Au deposits Current & Significant Past Producers Camp Production 21.6 M oz / 672 tonnes Au Other Deposits / Occurrences (Intermittent Exploration

Apr 1, 2005

By Manjeet Chowdhry, Qingxia Liu, Phillip Choi, Zhenghe Xu

Computational chemistry methods, such as density functional theory (DFT), are powerful tools to quantify reagent-mineral interactions encountered in sulphide mineral flotation. A quantitative relationship between theoretically calculated parameters based on chemical structure of collectors and their reactivity with different metals/minerals can provide valuable insights for design and development of more powerful and tailor-made reagents offering enhanced metal/mineral selectivity. DFT calculations at B3LYP/6-311++G(3df,3pd) level were employed to elucidate the reactivity of neutral sulphide collector reagents, including thionocarbamates (TC), thioureas (TU), xanthogen-formates (XF), dialkyldithiocarbamates (DTC) and dialkyltrithiocarbonates (TTC) with different heavy metal ions (Cu2+, Zn2+ and Pb2+) in solution. The extent of delocalization of lone pair electrons of heteroatoms (attached directly to C in C=S) over C=S group was found to be the dominant factor in determining the collector’s reactivity. Order of reactivity was established as: TU > TC > XF > DTC > TTC. All the collectors showed superior affinity towards copper followed by lead. Unidentate binding was observed through sulphur atom except for xanthogen-formate for which bidentate binding mode was observed. Effect of nature of substituent groups at N and/or O atom on reactivity of thionocarbamate and thiourea was also investigated. The results obtained through DFT calculations are consistent with the experimental data reported in literature.

Jan 1, 2015

By S. L. Gertsman

Canadian steel foundry practice has made marked progress during the past decade. Equipment suppliers, development engineers, and foundry personnel have focussed their attention on every phase of the foundry operation, with a resulting lower demand on manpower and materials. Also, more rigid specification requirements as to dimensional tolerances and quality have necessitated improvement and increased control at every stage from the pattern shop to the cleaning room. The growing trend toward mechanization is clearly evident. Equipment such as sand mixers, sand reclamation systems, material handling devices, moulding machines, core blowers, etc., is being increasingly employed by the steel foundryman. This equipment not only increases production but also tends to lessen the human variable so prevalent and disconcerting in the early days of steel founding. The result has been an improved and more reliable steel casting, which is gradually obtaining wider acceptance by design engineers. The purpose of this paper is to discuss briefly some of the practices being used, and also the direction of development that is being pursued by Canadian steel foundrymen.

Jan 1, 1948