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By Serge Ouellet

Identification and quantification of cementitious phases in cemented paste backfill (CPB) is difficult due to the fineness of tailings and the low binder content used in the mixture. Techniques such as X-ray diffraction and thermogravimetry were ineffective (mainly due to tailing mineral interference) to identify and quantify hydration products in most works reported in the literature. On the other hand, scanning electron microscopy (SEM) was used in many cases but mainly for qualitative purposes. This paper presents the development of a new approach based on a computer program (SEM-XMAP) that combines X-ray dot mapping images acquired by SEM and generates a coloured image representing the mineralogy and the microstructure of a given CPB specimen. The technique is applied to one CPB sample mixed with blast furnace slag (BFS) and acidic sulphated mixing water sampled in a mine dewatering system. The technique allowed identifying calcic matrix, unhydrated and partially hydrated BFS particles, and sulphated phases.

May 1, 2007

By Derek V. Ellis, Jack L. Littlepage

"Marine ecosystem effects ar1smg from the discharge of man-generated wastes to the sea can be schematized as: acute poisoning, chronic poisoning, enrichment, suffocation, temperature effects, salinity effects, toxin bio-concentration, changed production rates and changed species equilibria. A professionally designed site-specific monitoring program to check for such effects can not only safeguard the marine ecosystem from degradation, but it can also protect the industry involved from unanticipated remedial action after expensive construction has been undertaken. Monitoring programs should consist of three steps. Step 1 is an ecosystem survey which should be undertaken prior to final design of the discharge system and submission of applications for permission to discharge, because there can be considerable cost savings in obtaining information at an early stage in development. Step 2 involves location of the effluent field at the time of starting discharge, and analysing its dispersal behaviour. Step 3 consists of ecosystem monitoring with sampling stations and specific tests based on the accumulated prior information."

Jan 1, 1972

By W. G. Miller, J. D. Scott, D. C. Sego

ABSTRACT An overall study was conducted to evaluate the properties and processes influencing the rate and magnitude of consolidation for oil sands fine tailings produced using different extraction processes. As part of the overall study, a comprehensive description of physical and chemical characteristics of fine tailings generated by caustic and non-caustic processes was carried out. Ultimately, the influence of these fundamental properties on the compressibility, hydraulic conductivity and shear strength properties of the fine tailings was assessed. The characteristics of the fine tailings are presented in terms of index properties, mineralogy, specific surface area, water chemistry, liquid limits, particle size distribution and structure. A difference in water chemistry was concluded to be the cause of substantial differences in particle size distributions and degree of dispersion of the comparable caustic and non-caustic fine tailings. The degree of dispersion was consistent with predictions for dispersed clays established by the sodium adsorption ratio (SAR) values for these materials. A linear variation of increasing dispersion with increasing SAR up to a SAR value of about 40 has been suggested, above which fine tailings are completely dispersed. The observed dispersed or flocculated structures (viewed using a scanning electron microscope) supported the predictions based on SAR values.

Jan 1, 2010

By Fabien Miller

Automation technologies are increasingly envisaged to improve underground mining productivity. However, the technologies need to be used and adopted gradually in order to get the best benefits. This paper presents the technical and operational aspects of autoguided production vehicles at Brunswick Mine. During 2001 Noranda?s Brunswick Mine has successfully commissioned an automated haulage zone where two optically guided trucks transport ore from a remotely operated chute to two orepasses. Operational advantages include increased system capacity and enhanced safety and comfort for the operator. The data obtained up to now indicate that the system can operate reliably in mine production

May 1, 2002

By Kristopher John Shelswell

The work in this paper describes the theory, development and analysis of a computer model simulating a mine operation moving material using concurrent decline ramp truck haulage and skipping practices. This simulation was designed specifically to assess the performance of the truck haulage component and to expand on the scope and capabilities of traditional TKM fleet calculations. Haulage fleet simulation results were similar to TKM calculations for the lower to moderate production rate cases. However, comparisons of ramp-up and high production rate scenarios indicated that the simulation model was significantly more sensitive to operating practices and factors not accounted for by calculations derived when using a single TKM figure. Given the proper calibration of inputs and logic, the simulation model was additionally capable of providing information associated with general mine operations efficiency. Further benefits of the simulation model over a TKM approach included logistical assessments such as production schedule feasibility, productivity trade-off quantifications for proposed operating practices, and the validation of mine resource utilization scheduling. The simulation model was able to expand on traditional methods to approach planning and logistics by considering factors such as truck queuing, real-time traffic interactions, random events, and competition for resources on mine productivity.

May 1, 2013

By C. E. Baltzer

This paper highlights the electric power situation in Canada, and introduces brief explanation of the salient differences between electrical practice in the United States and Canada. The availability of bask energy in the two countries is touched on, also the hydro versus thermal outlook as applying to Canada. De-v2lopment of thermal-electric power is dealt with in some detail, followed by Canada's thermal-electric power requirements, present and future. The fuel requirements for steam-electric generating plant are assessed on the basis of a survey recently made, and the location and size of the major thermal plant operations are given. Fuel contractual obligations on the part ?of suppliers and consumers are mentioned. Finally, an opinion is expressed in regard to the types of f.uel in ?demand on a regional basis with emphasis on the need for coal in the several areas dealt with.

Jan 1, 1958

By Y. F. Jiang, K. Fang, Q. Q. Jiang, Q. Wu

Inter formational sliding of bedding planes between two different rock types in Badong formation is an important reason that leads to the instability and fracture of rock mass in this stratum. There are no specific research achievements on bedding planes between two different rock types in Badong formation. In order to study the shear mechanical properties of bedding planes between two different rock types. This paper using the software of particle flow code (PFC) and JRC model to establish several typical structures of different roughness coefficient of surface morphology based on the laboratory tests on silty mudstone and marlite in Badong formation. A great deal of numerical shear tests were carried out by ball production, radius expansion and servo infliction. The research results are as follows: First, shear strength of Badong formation is found to vary between that of silty mudstone and marlite isotropic planes by analyzing shear strength of the homogenous bedding planes and inhomogeneous rock types, we can find that the shearing strength in Badong formation is between silty mudstone and marlite isotropic planes and which is closer to the shearing strength of silty mudstone isotropic planes. Second, the basical friction angle of bedding planes between two different rock types in Badong formation is between silty mudstone and marlite isotropic planes and which is closer to the basical friction angle of silty mudstone between isotropic planes. Third, based on the experimental results, an expression is obtained to describe the relationship of the ratio of shearing strength between bedding planes of two different rock types and isotropic planes in soft rock, the rock combination coefficient, and the roughness coefficient. This study has important significance for further research on the shear mechanical properties of bedding planes between two different rock types.

Jan 1, 2015

By P. Choquet, F. Miller

"The development and testing of a simple low-cost gauge for measurement of tension in a cable bolt grouted in a borehole are presented. Its principle is based on a resistance wire which is wound on a 70 cm length into the spiral grooves of the wire strand cable bolt. Readings are then taken by a robust automatic data logger with a several day autonomy or by a portable readout. In order to have a complete profile of tension along the cable bolt, a number of tension gauges can be installed along its length.This paper provides a description of the development and laboratory calibration of the tension gauge and addresses the two modes of loading for a cable bolt in a rock mass, namely pure tension and shearing at a joint location.In the second part of the paper, four field tests in underground and open pit mines are reported. The first test was used to substantially modify both the gauge and the readout unit principles while the other tests which are still on-going show a very satisfactory behaviour of the modified version of the tension gauge. IntroductionCable-bolting is often used as ground support in Canadian mines for a variety of applications. In underground mines, cable bolts can be installed vertically at the back of cut and fill stopes or in an inclined fashion in the walls of large open stopes. Alternatively, cable bolts at Mines Gaspe (Noranda Inc.) are used in a fan-shaped pattern from a drill drift to stabilize the inclined roof in 25 m wide open stapes. This new application oriented our research efforts toward the design of a novel instrumentation to monitor the efficiency of most commonly used 5/8-inch cable bolts."

Jan 1, 1988

By R. Holmwood, M. Faris, P. Holloway, M. Collins

Sulphuric acid addition is a major driver of the economics in the processing of nickel laterite ores by high pressure acid leaching (HPAL). Understanding the optimal acid addition rate is essential for the success of any HPAL operation, and this is especially true at Ambatovy, where the composition of the feed tends to vary significantly on a day-to-day basis. Most studies on the effect of acid on nickel extraction in HPAL have used laboratory testwork as their basis. Although these studies are invaluable in assessing the economics of a new project, they are limited by the range of ore composition that can be tested and the differences between the operation of the laboratory equipment and the commercial plant. To enable optimization of the acid addition at Ambatovy, operating data from the HPAL operation were obtained using OSISoft’s PI system and the data from several periods were examined to develop relationships between acid addition and nickel extraction. The initial relationships from 2014 focused on the acid required to achieve a target nickel extraction of 95%, with aluminum and magnesium in ore and feed slurry solids content as the major variables. As Ambatovy ramped up through 2015 and 2016, the calculated acid requirement was further refined to address the effects of HPAL temperature and retention time, and the oxidizing/reducing characteristics of the ore, and to generate acid requirement relationships as a function of ranges of nickel extraction. These relationships supported raising the target nickel extraction to 96% and enabled the development of an economic model between acid addition and nickel extraction.

Jan 1, 2017

By M. F. Almeida

"Due to the randomness of all factors influencing the sintering operation, a two-stepped procedure is proposed to find the best way of using stocked fines at a plant producing Fe-Mn alloys for the steelmaking industry. The approach is based on the following: (1) predict the result of the sintering operation by establishing the best multilinear regression model using some of the characteristics of the loaded material; and (2) find the best solution under a minimizing cost criteria by solving a linear optimization problem using the regression equation plus constraints on the feed and product. IntroductionSome tests carried out using 20% to 30% of sinter in the material loaded into a 60 000 KVA Tysland-Hole electric furnace producing Fe-Mn alloys for the steelmaking industry indicated: (1) a meaningful decrease in the off-gas temperature and, consequently, a better energy use due to the material higher porosity; (2) more uniform heat distribution as a consequence of the electrode reaction zone enlargement; (3) an improved furnace control resulting in a smoother operation; and (4) a decrease in gas production facilitating the off-gas treatment. For some years, this plant used only the coarse fraction of the Mn ores, thus stocking all the received and own-generated fine particles. In view of the mentioned results, a strategy for increasing the use of stocked fines was formulated, including a step where it was necessary to decide which components and respective quantities should be used in the blends to be sintered (Almeida, 1984).It is well known that several factors affect productivity and energy consumption in sinter production, also influencing the product quality. Raw materials characteristics, namely chemical and size composition, affect permeability to gases and may or may not allow a deeper bed. In general, finer ores decrease permeability, increasing electricity consumption by fans, but due to their higher specific surface area, react more completely with other components in the mixture. For coke granulometry, a compromise must be obtained in order not to burn it too quickly nor to widen the flame front, therefore decreasing productivity. Decreasing coke in the blend also acts in sinter bonding, decreasing its consistency and increasing crushing and return fines. Moisture addition also influences components mixing, pre-agglomeration, bed permeability and, consequently, sintering productivity. Therefore, optimum conditions must be established for both a given sintering plant and the components in the feed (Dawson, 1993)."

Jan 1, 1998

By K. Eklund, T. Ahokainen

The Flash Smelting process is the most used production method for primary copper in the world. The basic idea of the Flash Smelting is to utilize the thermal value of sulfidic concentrates and melt the reaction product, in controlled conditions, without a need for external energy. This basic principle is utilized both in matte smelting and in Direct-to-Blister Flash Smelting Processes. In this paper, the behavior of normal (CuFeS2) concentrate of FSF-process is compared to the behavior of high grade feed material produced by Outokumpu Concentrate Upgrade Process with the aid of computational fluid dynamics (CPD) simulation using add-in subroutines developed by Outokumpu Technology. Results consist of the information concerning the behavior of the suspension, reaction efficiency and other parameters concerning the reactions of the feed material. It will be shown that, using the Upgrade Process, the throughput of copper from the Flash Furnace can be almost tripled.

Jan 1, 2007

By C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013

By S. Klingmann

ABSTRACT In this paper, we used data collected from the Gibraltar mine to analyze the effect of the TyreSense tire monitoring system on tire performance by reducing tire wear and preventing premature tire failure or damage. We analyzed the relationship between tire temperature, tire pressure, and tire failure or damage to help better understand the importance of controlling high tire temperature and pressure. The results enhance and expand the knowledge of the management of tire operational pressure and temperature.

Jan 1, 2014

By G. E. Willey

F OR many years, only one grade of structural steel has been used in volume in Canada. Its characteristics have not been altered appreciably and its long use speaks well for its performance. This standard grade of structural steel may be bought and specified as C.S.A. G40.4 steel or the American equivalent, A.S.T.M. A7. The principal limitations and requirements of this specification are shown in Table I. Within the last five years there has been a growing awareness among the steel producers and steel fabricators that economic forces are at work which make desirable the availability of new and better grades of structural steel. Competition from other materials has increased. The use of concrete bridges and pre-stressed concrete beams is a prime example. New sources of steel from outside the country have become a threat to the Canadian industry and its high cost-price structure. The need for improved properties in the steel, to make possible technologic

Jan 1, 1962

By J D. McDonald

This paper outlines the function of the Safety and Compensation Division of the Mining Association of British Columbia. After a general discussion of safety and the safety program now being followed in B.C., the author goes on to describe the wide-ranging aspects of compensation payments and company assessment rates. Special attention is also given to the problem of silicosis in mining operations. In appendices to the paper, the experience rating plan of the mining industry is compared to that recently adopted for the construction industry. Introduction The Mining Association of British Columbia consists of fifty-five member companies, including virtually all the producing mines as well as the larger exploration, contracting and development companies. On completion of an extensive study of safety and compensation in the mining industry, the Mining Association of British Columbia instituted a Safety and Compensation Division in 1954. The director of the Safety and Compensation Division reports to the Executive Committee of the Association. There are two main functions of this Division. First is the prevenion of accidents by encouraging

Jan 1, 1965

By S. G. Shabestari, S. Saeidinia, P. Mokarian

"The experiments were conducted to investigate the influence of various process parameters in rotary degassing of aluminum alloy AS5U3G. Degassing was carried out by use of argon inert gas. The flow rate of the gas was investigated in the range of 12 to 21 L/min., 350 to 500 rpm rotor speed, 6 to 12 minutes degassing time, and 755°C to 780°C melt temperature. Degassing efficiency was evaluated through measuring the density of RPT samples. By optimizing the process parameters, RPT sample density was increased up to 2.73 g/cm3, which guaranties the production of high-quality aluminum castings. Tensile strength and elongation were increased considerably by degassing process. Scanning electron microscopy (SEM) shows small size and well-distributed microporosity. IntroductionOne of the major problems associated with the casting of aluminum alloys is the formation of gas porosity. Aluminum and its alloys are very susceptible to hydrogen absorption. Because solubility is much lower in solid state than liquid state, hydrogen atoms leave their position during solidification and combine together to form hydrogen molecules. These micrometer- scale cavities, called microporosity, cause the reduction of mechanical properties, particularly strength, ductility, fracture toughness, fatigue resistance, pressure tightness, and corrosion resistance (Laslaz, 1991; Jorstad and Rasmussen, 1993; Sigworth and Wang, 1994; Korasani, 1996; Anson and Gruzleski, 1999; Zhang et al., 2000). To avoid these problems and produce good quality castings, it is necessary to remove hydrogen from the melt. Several methods are available for degassing aluminum melt. One of them is a rotary degassing system using inert gas, e.g. Ar or N2. Various thermodynamic and kinetic factors govern the removal of hydrogen from molten aluminum (Anderson, 1987; Sigworth, 1987; Pignault, 1993; King and Reynolds, 1995). These are some parameters that affect degassing efficiency. Some of them are discussed here and some are examined in this project."

Jan 1, 2004

By M. B. McClenaghan, O. P. Lavin, Ian Nichol

"Abstract-Exploration in most areas of Canada has to contend with problems posed by glacial overburden. In many areas exploration for gold has been based on the sampling of tills, frequently by deep overburden drilling, and analyses of heavy mineral concentrates. Notwithstanding the significant role that till geochemistry has played in the discovery of some important gold deposits over the last few years, increased appreciation of the nature of the glacial history and stratigraphy and the character of gold within till has led to the recognition of a number of ways whereby the effectiveness of exploration can be improved upon.In order for till geochemistry to be useful in exploration, a number of conditions must be fulfilled, including:1. mineralization, or alteration halo related to mineralization, subcropping at the bedrock /over­ burden interface; 2.glacial erosion and dispersal of a recognizable signature of mineralization into the glacialsediments; 3, preservation of glacial sediments containing this geochemical component (trace metal or mineral) at positions subsequently selected for sampling (normally drill sites); 4. correct identification of specific till units and associated ice movement history; 5. collection of adequately large and representative samples; 6. appropriate sample preparation and processing; 7, appropriate geochemical analyses; and 8. correct data processing and interpretation.While we have no control over the first two geological conditions, and only limited controlover till availability, we can control the quality and thoroughness of sampling, sample identification, sample preparation, analysis and interpretation. In particular attention needs to be focussed on obtaining a large enough sample to be adequately representative, an unbiased sample must be collected, together with appropriate sample processing, analysis, data processing and interpretation. It is considered that by modifying or extending existing approaches to gold exploration the chances of exploration success can be increased. In particular, analyses of both the heavy mineral and minus 63 ?m fractions of till is recommended because gold in till may occur in different size fractions."

Jan 1, 1992

By D. A. Livingstone

Abstract Golden Manitou Mines, Limited, nine miles east of the town of Val d'Or in northwestern Quebec, are presently milling, at the rate of 1,000 tons daily, a relatively complex 3.11-phide ore and producing, in decreasing order of value, zinc, silver, gold, lead, and copper. The products are a zinc concentrate, a silver-lead-copper concentrate, and a silver-gold precipitate from cyanidation. Although several independent pre-production metallurgical investigations into the treatment of the ore were carried out, current practice is different from any of the recommended methods and, while still leaving room for improvement, is considerably more effective than earlier performance. Flow-sheet developments from the commencement of operations in 1942 are dealt with briefly, showing the reasons for making numerous changes, the shortcomings of the various schemes tried, and, finally, covering data pertinent to present-day practice. From the recovery standpoint, silver has presented the greatest difficulty. The writer's association with the Company coincided with the start of production. Characteristics of the Ore The predominant metallic minerals present in the ore, in decreasing order of their abundance, are: pyrite, sphalerite, galena and chalcopyrite, with lesser amounts of argentiferous tennantite-tetrahedrite, arsenopyrite, covellite, bornite, and chalcocite. The sphalerite is mostly light in colour, sometimes colourless, and practically free from combined iron. Some of the sphalerite is very closely associated with minor amounts of pyrite, chalcopyrite, and galena. Pyrie is abundantly disseminated as medium to fine grains; more rarely it is massive and contains occasional grains of sphalerite, galena, and chalcopyrite.

Jan 1, 1952

By A. Roy MacLean

"In the Maritimes, there are twelve coal areas. From east to west, these include the Sydney coal field, the St. Rose - Chimney Corner, Inverness, Mabou, Port Hood, Pictou, Colchester - Debert, Springhill, Joggins - Chignecto, Beersville, Lake Stream, and Minto. The first eight are in Nova Scotia while the remaining four are in New Brunswick.In all these areas, the coal was formed during the Carboniferous period, which existed some 300 million years ago. However, within this period not all coal formation took place during the same time. There were three main intervals, which occurred at the time that the Riversdale, Cumberland and Pictou groups were laid down (Hacquebard, 1970). The oldest coals are those of the Riversdale Group. These coals were of rather limited extent, and only a few mineable seams are present, particularly at St. Rose -Chimney Corner and Port Hood. From these two areas only 2 M tons have been extracted, and 'measured' resources of 7 and 9 M tons respectively remain. The Cumberland Group coals are confined to Cumberland County and include the coals of Springhill and Joggins River Herbert -Chignecto. Some 43 M tons have been removed and only 7 M tons of 'measured' coal remain, with an addit10nal 39 M tons of 'inferred' resources. However, there are additional resources at Springhill, which will be discussed in more detail in a later section. The coals of the Pictou Group are the youngest and the most abundant, both in actual number of seams and in regional distnbution. These coals were formed during the Westphalian C and D, a time during which the main coal deposition in Europe also took place. Here belong the coals of the Sydney, Inverness, Mabou, Pictou, Debert, Beersville, Lake Stream and Minto fields. Their total production amounted to 469 M tons or 91 % of the Maritime total of 514 M tons. The remaining resources of all Pictou Group coals have been calculated at 254 M tons of 'measured' coal and 949 M tons of 'inferred' coal. As can readily be seen, the bulk of both past production and remaining resources occur in the Sydney coal field. The Sydney figures represent 73% of total production, and 87% of total 'demonstrated' resources in the Maritime Provinces. Next to Sydney, the Pictou coal field has been the greatest producer, with 59 M tons; it also has the second largest 'measured' resources, amounting to 25 M tons. However in terms of 'inferred' coal resources, the Mabou coal field, ~ith 140 M tons, ranks second to Sydney."

Jan 1, 1985

By J. Kabuya Mukendi, F. Brunet, J. Hadjigeorgiou, P. Matte, D. Leblanc, M. Grenon

La stabilité des bancs miniers est un élément important de la conception des fosses. Il n’y a pas de consensus sur les critères à utiliser pour évaluer la fiabilité des bancs miniers. Lors de la conception des fosses, la fiabilité des bancs miniers est analysée à l’aide d’un ou deux critères. L’objectif de cet article est d’analyser l’efficacité de la conception des bancs miniers de la fosse Tiriganiaq du projet minier Meliadine par rapport à des critères de fiabilité rencontrés dans la littérature et la pratique. L’article présente les similitudes et les différences entre les résultats obtenus pour les différents critères et propose une approche multicritère systématique pour évaluer la fiabilité des bancs miniers à l’aide de cartes de susceptibilité.

Jan 1, 2012