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By Jean-Luc Collins

"The paper deals with the impact of fleet imbalance on a deterministic evaluation of shovel fleet productive capacity. It shows that if the fleet imbalance is overlooked, then estimated fleet productive capacity will be overrated.The paper shows that fleet imbalance inflates utilization, and care must be taken when using such statistics which are derived from reported field-equipment-hours. It shows that the utilization must be deflated by a factor called 'balancing efficiency"" in order to estimate shovel productive capacity correctly. The paper also shows how fleet imbalance can be controlled by managing idle time or downtime in an actual operation.The technique used for measuring the balancing efficiency factor is based on statistical analysis of equipment utilization."

Jan 1, 1980

By Robert B. Parsons

"Canadian income tax legislation contains a number of provisions which serve to facilitate the structuring of business arrangements, including mineral resource ventures. These rules are often fairly complex and not easily understood. This article attempts to explain in plain and understandable language the mechanics and benefits of one of the more frequently encountered provisions, the ""Section 85 election"".IntroductionThe Canadian resource industries are probably singled out for more special attention under this country's tax legislation than any other industry. This special treatment is, of course, not always welcomed by the industry, such as where unnecessarily restrictive taxation is perceived to exist or where agonizingly complex tax legislation must be dealt with. On the other hand, certain provisions in the tax legislation treat the industry in a relatively favourable manner, including a number of rules which, in recognition of the high risk and capital requirements of the resource sector, serve to facilitate the structuring of resource ventures."

Jan 1, 1984

By Lesley Hymers

First Nations Natural Resources Youth Employment Program PDAC Mining Matters ? Charitable organization ? Provide education to students, teachers, and the public about rocks, minerals, metals, and mining ? Provide current information and offer exceptional educational resources that meet provincial Earth science and geography curriculum expectations First Nations Natural Resources Youth Employment Program ? Provide instructional development workshops for educators who are teaching Earth science and geography ? Since 1994, reached more than 400,000 students, teachers, industry representatives, and members of the public

May 1, 2009

By Friedrich Benthaus

"The natural and man-made realities on either side of the Atlantic are different. Therefore, a large part of the other side' s knowledge and experience cannot be transferred easily. In the following, the author will attempt to describe some of those developments in the German hard coal industry which may be of particular interest to readers on this side of the Atlantic.The area of the Federal Republic is quite small, especially if compared with a country as large as Canada. On a territory the size of the maritime provinces of New Brunswick and Nova Scotia, Germany holds coal reserves roughly corresponding to the total Canadian reserves. More than 20 billion tons of hard coal down to a depth of 1500 m, and more than 30 billion ton s of brown coal of lignite are technically and economically extractable acording to current technology.However, not only are Germany's coal resources more concentrated; the country is also densely populated, and there are dense networks of railroads and highways All components of the so-called infra-structure are available everywhere, be it electricity, any machinery or personnel. Public opinion is likely in favour of an increased utilization of coal.The coal industry is well developed through a long evolution covering centuries. As a consequence, there is an effective and intensive cooperation of numerous bodies and institutions concerned with coal mining, from government agencies including the inspectorate to suppliers, trade union s, producing companies, to jointly operated management and research organizations. In the Federal Republic, hard coal is mined in deep mines only, and lignite in general, only from open-cast pits. There is a complete organizational and geographic separation of hard and brown coal in Germany. Because the Federal Republic holds only insignificant mineral oil and very little natural gas deposits, coal is essentially the only and consequently the most valuable source of energy."

Jan 1, 1984

By Richard J. Kolada, Ian R. Muirhead

"This paper reports on a CANMET-funded examination of less conventional underground coal mining methods. These methods are documented and those that show the most promise for application to western Canadian conditions are discussed in detail.IntroductionIn recent years, mining considerations and economics have encouraged a transition from underground mining to surface mining. However, a change in market conditions or the development of superior underground mining methods may reverse this trend . Should this happen, the industry must be quick to respond and have information available on the latest developments of underground mining technology. In time, deposits of high-quality coal, which are easily accessible to surface mining, will be depleted and a change to underground mining methods will require consideration. The economic transition point between surface to underground will be a major determinant in maintaining a competitive edge. For these reasons, it is important to keep abreast of improvements in underground mining methods. To meet this objective, CANMET awarded a research contract to Monenco Consultants Limited, to investigate unconventional underground mining methods that show a potential for western Canadaoi. This paper presents the results of this investigation."

Jan 1, 1988

By J. J. Jonas

The categories of interpass time encountered in hot rolling are characterized. These are shown to fall into three broad categories: short (in rod rolling); intermediate (in strip processing); and long (in plate schedules). The effects of interpass time on recrystallization and carbonitride precipitation are described, and particularly on the interaction between these two mechanisms. The interactions, in turn, determine the final microstructure produced as well as the mechanical properties.

Jan 1, 2005

By H. M. Woodrooffe

IT IS WELL KNOWN that chrysotile asbestos from various occurrences exhibits varied physical properties and certain differences in chemical corn position, both of which conditions may have an important bearing on the industrial utilization of the fibre. The usefulness of a harsh fibre in the manufacture of asbestos cement products and of low-iron fibre for certain electrical uses are examples. It is also .possible to obtain a fibre with a texture too harsh and brittle to be of economic value. Much research into the structure of the mineral and to a lesser degree observations relating the water of combination to certain physical properties have ?been reported. This paper is an attempt to show that the pyrolysis of ?chrysotile takes place in three stages and that the conditions of pyrolysis are peculiar to the fibre and may afford some clue to the variations in physical properties of asbestos fibres which affect their utilization.

Jan 1, 1956

By K. J. Brouwer, J. P. Haile

"Construction of the first stage of the tailings disposal facility for the Montana Tunnels Project was completed in October 1986. The project is located 37 km south of Helena, Montana, and involves mining of42 million tons of weathered diatreme are at a rate or 13 500 tpd to produce a gold/silver dore, as well as lead and zinc concentrates. The tailings disposal facility for the project includes a fully drained tailings impoundment for storage of the tailings solids, and a process waterpond for storage of all decanted water prior to recyling to the mill. The over-all facility is designed to achieve the basic objectives ofminimizing seepage to the environment in the short- and longterm, and achieving a fully drained stable tailings mass suitable for immediate reclamation on completion of mining. Specific features of the design include a soil bentonite seal and drainage system within the tailings basin, a free draining embankment with a design flow-through capacity of 4000 US gpm and an ultimate height of 230 ft (70 m), and a soil bentonite lined make-up water pond with a capacity of 420 acre-feet (530 000 m'). The tailings will be discharged in a rotational sequence through multiple spigot offtakes to achieve a thin-layer low energy laminar flow. This 'sub-aerial' deposition results in higher stored densities and maximizes liquid-solid separation on the tailings beaches. The over-all design played a major role in the successful permitting of the project, and was significantly cheaper than a conventional wet disposal system, with overall unit costs for tailings disposal of less than US$0.36 per ton.This paper outlines the site characteristics and the tailings material properties and their influence on the design. Extensive use was made of naturally occurring free draining materials as well as bentonite modified soil liners within the tailings basin, embankment and retention ponds. General construction procedures for the various components are described, as well as on-going construction requirements utilizing materials from the open pit. Finally, the over-all costs and unit costs for tailings disposal are presented."

Jan 1, 1988

By M. H. Colebrook

Nickel laterites contain about 70% of all continental or terrestrial nickel resources; therefore the recovery of nickel from lateritic ores has large economic significance. The processing of lateritic ores involves the preparation and movement of concentrated aqueous suspensions. However due to complex characteristics and non-Newtonian properties, ranging from shear-thinning to shear-thickening and from thixotropic to rheopectic, a basic understanding of the flow behaviour must be developed. This understanding will assist in the development of new plants and the operation of existing plants. The work in this paper involves the characterization of three ore types from the Vermelho ore deposit to categorize them as rheologically simple to complex. Rheological testing was also conducted on pure mineral samples that represent the main minerals in these samples. The results show that the rheological properties of the ore types can be related to the surface properties and physical characteristics of the main mineral constituents.

Jan 1, 2006

By B. Das

"Computers have been used extensively in the mineral industry in exploration, reserves calculation, mining technology, mineral processing, etc. With respect to coal mining, there are also various applications for evaluating rock slope stability of open pits, design of open pits, underground operations, mine ventilation, ground control, data processing and management information, operations control and certain technological applications. Mine ventilation appears to be the field in underground coal mining touched on most; on the other hand, underground coal mining methods evaluation is represented only sparingly.It is therefore essential to review the status of the computer in underground coal mining methods evaluation in order to define its scope for further application. The paper discusses the roles of the mining engineer, programmer, computer operator and analyst as well as that of the computer. The important parameters will be identified and discussed along with their application for different underground coal mining methods, with their individual unit processes. Mainly, longwall face operations have been covered. Although many models have been of academic interest, they can be considered as important steps in a transition stage which will be followed by more practical applications for computers for underground coal mining method evaluations in the future. This calls for a coordinated effort from all concerned."

Jan 1, 1981

By G. R. Davidge

"Falconbridge Mine has a history of significant microseismic activity dating back to 1955. Since mid-1981, a microseismic monitoring system has been operating in the area around the No .9 Shaft hoist room located 25 m from the are zone at a depth of 1200m. Several mine wide faults dissect this area and have been shown to be microseismic-active due to mining. The microseismic monitor has been interfaced with a small dedicated personal computer and a communications device to perform routine data evaluation and to produce graphical output. The programs are described and selected result s from the monitoring program are presented.IntroductionFalconbridge Mine is located on the southeast rim of the Sudbury Basin. The nickel-copper sulphide ore zone is essentially a tabular orebody striking approximately east-west and dipping at 80 degrees north near surface and rolling to 75 degrees to 80 degree s south by the 1000 level. (Mine level number s represent the approximate depth in feet below ground surface .) This dip is maintained down to the 6000 level. The north wall is comprised of jointed norite and a faulted contact up to 1 m thick exists between the ore zone and the norite. The south wall rock is a greenstone with highly siliceous lenses and often has a faulted contact with the ore zone. No less than five mine wide faults exist, as shown in Fig. I.Mining ha s been carried out from virtually the bedrock contact to depths of 1830 m although the majority of current activity is between 900 and 1500 m below surface. A winze provides access below the 4025 level and the cage hoist room is located on the 3850 level in the north wall 25 m from the contact. Because of concern for the stability of this hoist room, there has been no mining activity within 60 m of the hoist room and by 1980 this block of ore was one of the major blocks of high-grade ore remaining in the mine . Mining of this block was originally scheduled for very late in the decade.Prior to a six-month shutdown in 1982, this mine produced approximately 450,000 tonnes of ore annually, mainly by cut and- fill techniques. Following the shutdown, annual production has been reduced to approximately 200,000 tonnes and production is now mainly by undercut and fill techniques .Mining-induced seismicity has occurred at Falconbridge Mine since at least 1955 and reviews of the microseismic problems for the periods from 1965 - 1970 and from 1971 to 1979 were made by Singh (1971) and Vongpaisal et al. (1980), respectively. The need for instrumentation was addressed by these authors. Following several large events during the spring of 1980, a decision was made to investigate existing microseismic monitors and to apply micro seismic monitoring techniques in Falconbridge Mine. Application of microseismic monitoring to Falconbridge Mine was to concentrate on the No . 9 Shaft hoist room area of the mine, particularly around the 4025 level where a large mechanized cut-and- fill stope was approaching this level. By mid - 1981, the microseismic monitor was fully installed and with in a year , a short-period seismograph and a personal computer had been added to the system."

Jan 1, 1984

By I Wilkomirsky

The neutralization of S02 from copper smelter gases to produce calcium sulphate (anhydrite) is considered an attractive alternative to sulphuric acid production. To develop the required technology for the process, a three-stages fluidized bed reactor prototype was designed and operated using both high and low grade limestone and gases with 2, 8 and 12 vol -% S02. The results obtained shows that at 800°C and up to 8 vol-% S02 in the gases, the capture of S02 reaches near 99% with limestone conversion to anhydrite of 45 to 48%. A larger pilot plant is presently being built at the Codelco El Teniente-Caletones Smelter to demostrate the technology and to evaluate the economics of the process. Cu2007

Jan 1, 2007

By S. S. Rahman, A. Gholami, M. A. Aghighi

"This paper provides a foundation for studying the growth of fractures in presence of other discontinuities and different anisotropies of low permeable hydrocarbon formations and helps to improve the design strategies for multistage fracturing.The multistage fracturing technology has recently been used to exploit low permeable hydrocarbon reservoirs. However, the mechanism of hydraulic fractures interaction and the impact of local heterogeneities on ultimate trajectory of the growing hydraulic fractures are not yet understood in depth. A fully coupled poroelastic Finite Element based model is developed to investigate the mixed mode propagation behaviour of growing hydraulic fractures. This model takes advantage of an explicit representation of the fracture which enables us to take the effects of rock and fluid related parameters into account. Moreover, impact of fracture geometry and leak-off phenomenon is investigated. The refined mesh around the crack provides the added advantage of more detailed stress distribution, pore pressure change and back stress in the vicinity of the fracture and in particular at the fracture tip. The potential deviation propensity of the fractures is evaluated based on the fundamental rule that fractures propagate perpendicular to the direction of the minimum horizontal stress.This study shows that pressurization of transverse hydraulic fractures results in the reorientation of local principal stresses, particularly in vicinity of fracture tips. Variation of flow patterns clearly influences the evolution of shear stress around the fracture tips which will potentially lead to mixed-mode I and II fracturing and consequently, fracture deviation. The presence of local heterogeneities such as preexisting fissures and/or fractures is a main source of such pore pressure induced stress redistribution and reorientation and potential deviation of hydraulic fractures.Most existing models ignore or simplify the effect of pore pressure/stress coupling as well as the fracture geometry and fluid flow within the fracture. Also, the fluid leak-off from the hydraulic fracture into the formation, which is a controlling factor in fracture growth, is often considered using analytical models. Taking advantage of a fully coupled porelastic model along with an explicitly discretized fracture, this study provides a more realistic insight into the complex fracture propagation processes of multistage fracturing operations particularly in presence of reservoir geo-mechanical complexities."

Jan 1, 2015

By Jason Berenyi

Presentation Overview ? What is Potash? ? Where are the potash deposits? ? Current potash mines ? production, capacity and planned upgrades ? Saskatchewan Saskatchewan?s Potash Production Potential s ? Current Status of Potash Exploration ? Increasing Demand for Potash ? Saskatchewan global role

May 1, 2009

By Richard Cyr, Peter Larsen, William Quesnel

"The need to continually improve efficiency and lower costs in mining operations is of paramount importance to all concerned in the industry. Mining operations are constantly testing new methods and equipment in order to lower costs and improve productivity. Equipment suppliers strive to fulfill the demands of the mines through improved design and innovative ideas for productivity increases. In some cases, however, an increase in productivity does not require new equipment design, but rather the application of an existing mining method into different operating parameters. Such is the case in applying longhole methods to narrow vein ore deposits.Bulk mining methods have long been recognized as efficient, low-cost alternatives in narrow vein operations. Typically, shrinkage and some cut-and-fill methods are employed. The shortfall of these methods is the tendency to be labour intensive. The demand for miners skilled in these methods far outweighs their availability. Consequently, labour-efficient methods have to be employed to fill the void. The application of longhole drilling techniques to narrow vein deposits is one such method.IntroductionPercussion longhole drilling evolved in Canada in the early 1940s. Prior to percussion drilling, blast holes were drilled using diamond drill equipment. Jack Gardner, of Gardner Steel, began testing with carbide percussion bits and extension drill steel in applications where diamond drills had been previously employed. Percussion drilling equipment proved to be considerably more productive and cost-efficient. The experiment eventually led to the replacement of diamond drills in this application.Over the years, the percussion methods were improved, with particular emphasis on the equipment used. Rifle bar rotation machines evolved to independent rotation. Bar and arm set ups evolved into self-contained mobile drill carriers that increased productivity while reducing the physical labour. The introduction of hydraulics further improved efficiency and production figures. Today, it is not uncommon to see fully computerized jumbos in production longhole drilling applications. These machines represent the ""state-of-the-art"" in longhole drilling equipment.Production longhole drilling is considered to be one of the most efficient bulk mining methods in use today. Production statistics normally exhibit low-cost, efficient ore extraction. As a rule, longhole (blasthole) methods are associated with substantial ore deposits. These methods have exhibited high production figures and low mining costs.Over the past decade, long hole methods have been applied to several narrow vein deposits. These applications have proven that, given the right parameters, longhole methods will produce the same advantages in narrow vein deposits as are seen in more conventional applications."

Jan 1, 1990

By D. E. M. Plaumann

"The wet grinding of asbestos has attracted the attention of engineers for many years as a means of improving fibre liberation from the ore. Today, added impetus for wet grinding has resulted from a need to minimize worker exposure to asbestos dust in conventional dry mills using air, as well as a need to provide a cleaner, technically superior fibre for use by product manufacturers. However , high viscosities of asbestos slurries create transport and grinding difficulties which have been a factor impeding use of a wet grinding process.Laboratory evaluation of reagents to reduce viscosities of asbestos slurries found that one reagent, XFS-4272.00, reduced the viscosity of a 35% (by weight) slurry by 75%. The impact of XFS-4272.00 on actual grinding parameters were evaluated using a pilot plant rod mill. Slurries containing 78% solids and XFS-4272.00 were successfully milled and asbestos fibres from that milling compared favourably in liberation and relative surface area to asbestos fibres obtained from milling a 4% slurry without additives.IntroductionAlthough the use of asbestos has been declining over the last few years, the large deposits of chrysotile in eastern Canada (Quebec in particular) remain very important. Asbestos production in Canada stands ninth in volume for mineral production with over 740 000 tonnes produced in 1985. Of this quantity, 722000 tonnes were exported with a value of $446 million . Canada is second in world production of asbestos behind the U.S.S.R ."

Jan 1, 1988

By Jacque Turgeon, Gontran Foy

"The Mineral Research Centre of the Quebec Department of Energy and Resources has worked extensively on the development of a dry process to extract pure mica flakes from a phlogopite ore. The liberation of mica from the gangue is effected basically by impact crushing, and the ground ore is screened into several fractions, each having a fairly narrow range of grain size. Each sized fraction is then fed to an air separator where heavy grains are separated from light flaky grains. Heavy fractions are returned to hammer mills where gangue minerals are ground finer and blocky mica particles are exfoliated. A second stage of screening is performed and each fraction is sent to an air separator. This sequence is repeated until mica products are virtually free of gangue. These different fractions are then treated in a cage mill in which mica flakes undergo a more orderly exfoliation along cleavage planes. The ground mica is again submitted to a final screening stage, after which each fraction constitutes a final commercial product.This process permits the recovery of about 70% of the mica contained in the ore. The over-all process will be described along with technical details of each unit operation. Recent work on a wet grinding method to produce very fine mica will also be discussed.IntroductionRecords of production of mica in Quebec date back to 1886. Production has been more or less continuous since that time, with peak activity during the war years. Production was interrupted in 1966, but started again in 1972 when Marietta Resources and Laviolette Mining and Metallurgical Corporation started their joint operation in Canton Suzor, northwestern Quebec. Mica deposits of more or less importance exist in different parts of Quebec, of which three have attracted attention in recent years: the Canton Suzor deposit, the Canton Lamy deposit and the Canton Chasseur deposit. The Suzor orebody was first identified by Carl Faesler in 1936, who described the rock as ""brown biotite in flakes half an inch in diameter, with interstitial augite, apatite and feldspar""."

Jan 1, 1982

By R. E. Lawless

The transportation challenge began with the need to move millions of tons of coal annually from Western Canada to Ontario. The paper will discuss the options which were available, the final mode selected and the economic trade-offs which were involved. It will outline the demands of unit train technology and the effect of transportation requirements on the other elements of the whole system.

Jan 1, 1979

By M. Scobie, T. Atkinson

"This paper reviews the development of new designs in extensible and high angle conveyor systems. These aim to overcome the limitations of prior alternative concepts in design. The application of such systems in strip, terrace, open pit and mountain mining is reviewed. IntroductionTruck haulage costs have tended to escalate in recent years. This has been primarily due to operations generally moving to greater depths with associated increases in haul distances . Periods of high inflation rates have also been experienced for diesel fuel oil, tires and other petroleum based products. Recent international political events have tended to regenerate concerns over future oil supply and price stability. For such reasons, conveyor based transport is becoming increasingly attractive. Truck haulage maintains an inherent flexibility and improvements continue to be made in performance and capacity. Doubts must exist, however, over the extent to which further economies of scale may be made. Conversely, belt conveyor systems do not suffer this constraint and have the following advantages:• Electrical power is used and the specific energy consumption is at least half that required for truck haulage.• Operating costs and skilled labour requirements are lower.• Equipment has superior longevity and is ""inflation proof"" .• Access roads can be steeper and narrower in most mine environments, reducing construction and maintenance costs.• They are less prone to breakdown and bad weather delays .• In long haul, high capacity operations conveyors can save substantially on capital cost.• Environmental impact is improved with reduced noise level, dust and atmospheric pollution. Although conveyor systems are less flexible in operation than truck haulage and although a breakdown in any part of the system can immobilize the total system, mechanical availabilities of + 80% are constantly reported by large operators. There would appear in the past to have been some prejudice against conveyor systems in hard rock mines due to lack of experience. Apparent reservations would apply equally 10 underground coal mines, yet practically all of these mines (and some underground hard rock mines) find conveyor systems more economical than other transport systems."

Jan 1, 1991

By J. A. Bossert

"In 1957, the Department of Mines and Technical Surveys (now Energy, Mines and Resources Canada) issued their first certificate for a fire-resistant conveyor belt. The testing procedure used was a combination of those used in the U.S.A. and the U.K. Subsequently, certification was granted to fire resistant electric cables (1974), fire-resistant mine duct material (1976) and fire-resistant hydraulic fluids (1978).Until recently, the testing procedures were copied from either the U.S. or the U.K. However, since the founding of the new Canadian Standards Association (CSA) Steering Committee for Electrical/Mechanical Mine Safety in 1981, these requirements have come under the close scrutiny of new CSA technical committees who will attempt to adopt or change the existing procedures to meet Canadian needs. This paper outlines the existing test requirements and attempts to predict how they will appear after ""Canadianization"" by the CSA committees.IntroductionFires in underground mines have always been considered more serious than in other locations because of the confined space and limited atmosphere. A fire can make escape difficult or impossible if it is blocking all of the routes to the surface. Also, the products of combustion from an underground fire can asphyxiate anyone not having self-contained breathing apparatus.In an underground coal mine, the consequences of a fire can be even more serious because of the presence of methane and coal dust in the atmosphere (which can explode) and because the coal itself is combustible.For these reasons, the inspection authorities having jurisdiction over underground mine s in Canada are quite concerned about the flammability of any materials that are used in quantity in the underground environmentAs early as 1957, the Canadian Explosive Atmospheres Laboratory (CEAL) was asked to certify conveyor belting as fire-resistant. This is because many miles of this material are used in underground mines in Canada and, as it generally travels through the mine, it is a perfect vehicle for spreading a fire."

Jan 1, 1982