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By D. A. Pirttinen

The promotion of improved coal quality for thermal generation can benefit our national economy. The construction of electric generating facilities in Canada is expanding at a rapid rate to satisfy the demands of a rising population and new uses for electrical energy. With remaining economic water power resources in the process of development, generation from thermal sources continues to grow. The increase in thermal capability has been somewhat arrested by a de-pressed economy, widening of inter-provincial and state transmission networks and decisions to exploit certain water resources before high capital investment is further in-creased by rising construction costs. The introduction of extra high volt-age transmission lines will further delay thermal generation planning, but in due course, when the effects of restrictive factors have been dissipated, steam-electric generation from fossil fuels will rise to considerable proportions. In time, nuclear sources will contribute a growing share to thermal power, but, it is doubtful if nuclear participation will ever displace conventional fuels for steam rising, unless it can be adapted to operate efficiently for variable outputs in peaking service. It appears certain that fossil fueled

Jan 1, 1961

By R. D. Hossack

"The selection of a site for plant facilities is a function of several factors and has as its objective the maximization of profits, given fixed markets and sources of raw material locations. In practice there are several sites, any one of which or a combination of two or more would be suitable to meet the basic requirements of source of supply of raw material and labour and still fulfill market demands. The model used to select the optimum profit combination utilizes both computer programs and traditional financial analysis techniques. Of the three computer programs used in the mode), one is a linear program and another is a transportation simulator. Basic cost and price data are required. In examining costs, three levels are used: (a) distribution costs of raw material to the plant and finished goods to the market; (b) direct production costs at the plant, such as labour and locally supplied material; and (c) capital and overhead costs at the plant, such as construction costs, taxes, insurance, and federal and provincial cost allowances. The direct costs generally depend on the scale of operations, so that a large plant in one location may have a lower unit cost than two smaller plants. This, of course, must be balanced against distribution costs. In examining profit, it is necessary to think in terms of the price and volume of sales at each of the market locations. Given basic data and relationships, the model can be used to optimally locate production facilities or, alter-natively, optimally structure a transportation network given existing locations of plants and markets. It is dynamic to the extent that it can react to changes in volume, price and cost to optimally locate an additional plant, the expansion of existing plants, the shutting down or cutting back of plants, or the restructuring of distribution networks."

Jan 1, 1970

By M. Gagné, F. E. Goodwin

The mining industry represents a significant investment in infrastructure of which steel plays a key role. Many structures in a mine are made of steel including shaft structures (buntons, station steelwork and headgear); stope structures (roof supports, pipe hangers); haulageway structures (ore transfer stations, electrical stubbies); and surface structures (plant buildings, tank supports, pipe gantries, conveyor belts, stacks, stockpile structures, stairways and railings). Maintenance of structural components can often be difficult because of the environment, including those where corrosive fumes persist, or limited access, such as in shafts where access is limited, or to short maintenance shifts or where limited working space is available. Thus a cost-efficient, long-lasting and maintenance-free protection system for steel should be specified. Galvanizing provides the required high-quality, long-term corrosion protection to steel. Galvanizing provides protection in two ways, first as a physical barrier to corrosion and secondly by means of cathodic or sacrificial protection that is unique to zinc. The dual nature of corrosion protection provided by galvanizing significantly extends the service life of steel even in the most challenging environments. The unique corrosion protection properties provided by galvanized steel will be highlighted with global mining application case studies.

Jan 1, 2015

By G. D. Bateson

"The Low NOx/SOx (LNS) Burner is a technology which, in pilot-scale tests, significantly reduces acid rain-forming emissions from the burning of coal. The precursors of acid rain are nitrous oxides (NO) and sulphur dioxide (SO:;) . TransAlta is currently planning two demonstration projects.Esso Resources Canada and TransAlta are undertaking a project to demonstrate how coal can be burned cleanly for steam raising in heavy oil operations by using TransAlta's LNS Burner on a steam generator at Esso's Cold Lake Production Project. The $10.7 million project started up in mid-J990, with testing to be completed in mid-I99J. The province of Alberta and Western Economic Diversification Canada, along with other private industry, are contributing funding to the project.The other demonstration project that has been selected for funding under the United States Department of Energy's Innovative Clean Coal Technology Program is a retrofit of LNS Burners to a 33 MW cyclone unit at Southern Illinois Power Cooperative's Marion generating plant. The US$13.6 million project is scheduled for completion 18 months after final funding arrangements are made.TransAlta believes that these demonstrations will lead to the development of a commercial ""clean coal"" technology. Other demonstration projects being planned will further broaden the base of applications.IntroductionTransAlta has recognized an increasing concern worldwide for the environment, and in particular the acid rain problem. Increasing public concern and the need to meet either current or possibly more stringent emission regulations have prompted them to explore various emission reducing technologies - despite the low sulphur content of its coal.The flue gas desulphurization (FOD) and selective catalytic reduction (SCR) technology currently available to reduce sulphur and nitrous oxides from coal burning power plants is very costly. Having to incorporate FGD technology, or ""scrubbers"", greatly adds to the cost of producing power. Having to add such high costs to electric customers' bills is something TransAlta is striving to avoid.There are many research programs now underway which are evaluating ways to provide electricity from coal in a clean manner. TransAlta has been observing or participating in a variety of these programs. However, there is one new technology which the company has identified as having the potential to control acid rain causing emissions at a fraction of the cost of conventional systems. That technology is called Low NOx/SOx, Burner - or LNS Burner."

Jan 1, 1990

By C. Riveros, H. Henein

Bulk Metallic Glasses have a high potential as advanced engineering materials due to their various properties including strength and corrosion resistance, to name a few. This paper investigates amorphous phase formation and rapid solidification characteristics of impulse atomized Co-based alloys in order to understand and control the application properties of the final products. Amorphous fraction and kinetic crystallization properties of the atomized Co-based alloy powders were quantified by means of Differential Scanning Calorimetry. In addition, different but complementary characterization tools were used to analyze microstructures of the powders. These include optical microscopy, X-ray diffraction and micro-hardness tests. While the amorphous fraction within the powders is promoted by high cooling rate and smaller powder size as expected, hardness is found to decrease with the fraction of amorphous phase.

Jan 1, 2015

By C. J. Preston, R. E. Ström, G. R. Baiden

"On January 1st 1996 Inco Limited, Tamrock OY, Dyno Explosives Group and CANMET formed a consortium for the development of robotic mining equipment. This project is a five year research and development agreement that combines the talents of the above organizations to facilitate the creation of mining equipment and systems for robotic mining.The projects are based on the communication system developed by Inco Mines Research and currently sold and marketed by Automated Mining Systems Limited. Main projects include the development and implementation of a positioning and navigation module (including a software mapping system that will be inherent to each piece of equipment), robotic systems for development and mining, and software systems to support the use of this equipment. Included in the program is the establishment of a test mine, at Inco’s 175 ore- body at Copper Cliff. This facility will allow collaboration of companies and research organizations for the design and testing of techniques and equipment for Robotic mining.This paper discusses the creation of this new research alliance, the Mining Automation Program or MAP."

Jan 1, 1997

By Xiong Tong, Jiushuai Deng, Yingbo Mao, Lingyun Huang

Ammonium carbamate has been used as a reagent for the leaching of copper from the copper oxide ore found in the Honghe state, Yunnan province, China. In order to find the optimal conditions for the leaching of copper from this copper oxide ore,the effects of several processing parameters, including the concentration, time, temperature, particle size and stirring intensity have been investigated. The results of these optimization experiments showed that the leaching rate of copper reached up to 72.76% under the following conditions: liquid-to-solid ratio of 10:1, ammonium carbamate concentration of 2.5mol/L, leaching temperature of 45 °C, stirring speed of 300rpm, a reaction time of 1.5 h and 85% by weight thereof passes through a sieve having 0.074 mm.

Jan 1, 2015

By B. Hohenstein, B. McBain, B. de Jong

"The automated fire assay system (Fast In-line Fire Assay or FIFA) has not found acceptance in the Au mining industry as the lower measurable limit of 0.20 ppm did not allow Au tailings to be measured with confidence. The development of arrested cupellation has overcome this hurdle which was a limiting factor in the FIFA 1 process. In the new automated fire assay process, automated sample preparation, fluxing, fusion and separation of a Pb button are essentially similar to the FIFA 1 process, albeit with some improvements. However, the game-changer is the development and incorporation of arrested cupellation into the automated system, now called FIFA 2. The purpose of arrested cupellation is to reduce the 50 g Pb button to a 5 g Pb button by partial cupellation in a specially developed arrested cupellation system thereby concentrating the Au in the Pb by a factor of 10 and in so doing moving them into higher concentration ranges in the mini-button where they can be read on the spark spectrometer. Results show that concentrations down to 0.02 ppm Au in geological materials can now be determined using arrested cupellation in the FIFA 2 process, an order of magnitude improvement over FIFA 1.INTRODUCTION Traditional fire assay for Au has remained virtually unchanged for 3000 years. It has survived for so long because it is accurate, has relatively low detection limits and is relatively inexpensive. However, it is labour intensive, has a long turn-around time (typically at least 7 hours), is environmentally unfriendly and exposes assay operators to potentially unsafe conditions (toxic fumes, toxic dust and extreme heat from furnaces). The NiS collection method is not as effective for the assay of Au as it is for the PGEs. A rapid, accurate, cost-effective method for the determination of Au and the Platinum Group Elements (PGEs) in geological materials would be a tremendous benefit to mining companies. Many of these objectives have been met by the FIFA 1 (Fast In-line Fire Assay) developed some 15 years ago in which automated methods have replaced the manual procedures which are part and parcel of conventional fire assay. However, concentrations below 0.2 ppm have been very difficult to achieve with sufficient reliability."

Jan 1, 2017

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 Hao Zhang

Site inspection is an important component of safety management system. In current practices, the inspectors evaluate the safety condition on a construction site with the assistance of a standardised checklist. However, the checklist emphasizes on evaluating the implementation of safety management system, but provides limited task-specific check items for assessing whether the individual construction tasks are conducted under safe condition and in a safe manner. To address this issue, the research presented in this paper aims to provide safety practitioners with comprehensive and taskspecific safety information to promote effective risk identification and facilitate strategic risk control during site inspection. Specifically, this research first builds a project-specific safety information database, which stores potential risks and control measures for each construction task. The research team then develops a mobile decision support tool to retrieve information from the database and support safer decision-making on site. The tool supports users in two ways: one is to provide daily risk checklists and risk control strategies to guide step-by-step inspection alongside the project schedule; the other is to let users input any safety-related keywords during the safety inspection process and the tool returns relevant safety information by applying text mining algorithms. It is ongoing research. This paper presents an overall research framework and discusses the progress in developing safety database and data retrieval concepts. The outcome of the project will help enhance safety management practices and reduce possible risky working conditions on a construction site.

Aug 1, 2013

By Xueyuan Nie, Xuezhi Zhang, Henry Hu, Shen Xinwei, Jimi Tjong, Li Fang

With the demand for weight reduction in vehicles and airplanes, researchers have shown great interested in casting wrought aluminum alloy 7075 because of its potential advantages such as high strength-to-density ratio and stress-reduction capabilities. It is therefore essential to conduct a fundamental investigation on solidification behavior and grain microstructure of alloy 7075. In this study, a commercially-available wrought aluminum alloy 7075 was used to study the solidification behavior of alloy 7075. A thermal analysis was performed based on the cooling curve and its corresponding first and second derivative curves. The nucleation of the primary a-Al phase and eutectic phases were analyzed. The comparison between the microstructures of the wrought and cast 7075 alloys shows that coarse microstructure and porosity are present in the cast alloy. The techniques for grain refinement in casting, such as the addition of the nucleating particles and applied pressure, should be employed to reduce the dendrite arm spacing and the porosity.

Jan 1, 2015

By S. Hume, J. Shepherd

Meso-2,3-dimercaptosuccinic acid(DMSA) was studied as an additive for thiosulfate leaching of gold. DMSA was added to solutionscomposed of either sodium thiosulfate or calcium thiosulfate and the solutions were tested for their ability to leach pure gold samples as well as a calcined gold ore from Barrick Gold Corp. Results showed prolonged leaching of pure gold samples when DMSA was added at a concentration of 5µM; however, higher concentrations were shown to inhibit leaching. Differential capacitance measurements of the interface indicated that DMSA adsorbed as a defective monolayer on the surface of gold at low concentrations and formed a more compact monolayer with increased concentration. It is proposed that a concentration of 5µM DMSA produces a defectivemonolayer on the surface that still allowsthe transport of oxidants to the underling metal while inhibiting the formation of polysulfide passive layers that arise fromdecomposed thiosulfate.The 5µM DMSA/CaS2O3 system was also studied using calcined ore. Results showed that the initial leaching rates in the presence of DMSA are lower than those obtained in thiosulfate alone. However, after 10h, prolonged leaching is again observed when DMSA is included.

Jan 1, 2015

By Fazel G. Jahromi, Ahmad Ghahremaninezhad

Enargite (Cu3AsS4) is a major complex copper mineral and often is a carrier of invisible gold particles. Pyrometallurgical treatment of enargite is challenging due to the arsenic release to the environment. Hydrometallurgical treatment, on the other hand, appears to be a promising alternative for enargite processing. In an atmospheric enargite leaching process both the copper and arsenic from the mineral can be leached into a sulphuric acid solution and the arsenic can be simultaneously precipitated as ferric arsenate. The unlocked gold in the residue then can be recovered in a subsequent cyanidation circuit. The downside of the atmospheric enargite leaching in sulphate solutions is the slow leaching kinetics. In this study the effective parameters of the atmospheric enargite leaching process in ferric chloride media were investigated. All the experiments were carried out at temperatures below 100 °C. The process parameters that were investigated in this study included ferric, chloride, sulphate and cuprous concentrations, temperature, mixing rate and leaching slurry pulp density. It was found that the copper recovery rate increases with the addition of cupric chloride and also with raising the temperature. The highest leaching kinetics and the highest overall copper recoveries were achieved when cupric was initially added to the leach solution and at 90 ºC.

Jan 1, 2015

By T. G. Joseph, E. Lampard

ABSTRACT: Surface mining operations must manage variability from within their operations as well as variability imposed upon them by external forces. A framework to manage both internal and external variability through the continuous review and adjustment of a mine plan during active mining lifetime operation is introduced, to minimize lost production and maintain operational safety. The observational approach of “observe, evaluate, interpret, predict, and adapt” is employed as the backbone of this approach. Although written with a surface mining operation in mind, the framework outlined in this paper would be equally applicable to any mining or processing operation.

Jan 1, 2011

By I. B. Lambert

The guide has been developed by officials from resources and environment agencies in the Australian Government and the South Australian and Northern Territory Governments. It elaborates on the Australian Government?s policy that new uranium mines are to be approved subject to world best practice environmental and safety standards. The guide outlines the best practice principles and approaches that apply generally to mining in Australia, before giving more detailed consideration to best practice environmental protection and regulation for ISR mining.

Aug 1, 2010

By L O. Montpetit

The economics of the asbestos mining industry of Canada, and the physical and chemical characteristics of asbestos fibre, as well as exploration, mining, milling and quality control methods, have been described by several authors in the past few years. The scope of this presentation is to survey the application of asbestos fibres in the major product groups of the construction industry in North America. Principal categories considered include flooring materials, asbestos-cement pipes and building products, high-temperature insulation, textiles, saturated asbestos felts and asphalt com pounds. During 1962, the asbestos mining industry of Canada produced an estimated 1.3 million tons of chrysotile fibre grades, and production capacity is expanding. The market demand for chrysotile fibre, on this continent, has been in the order of 50 per cent of the production volume. The asbestos industry is dependent for growth on the construction industry. Product research is active in finding new uses for asbestos fibre; some of the new developments are presented, including the use of short-fibre asbestos grades for extending the life of asphalt pavement.

Jan 1, 1963

By L. Gonzalez-Sardi, W. McCombe, M. Pearson

Pressure oxidation is increasingly being used for processing refractory sulphide ores and concentrates because it offers highly effective base metal and precious metal extraction while minimizing elemental sulphur, arsenic & mercury emissions. Yet pressure oxidation processes introduce new safety concerns and process risks as demonstrated by a number of safety incidents over the last 20 years, including overfilling, oxygen-metal fires, nozzle/sparger failures, and uncontrolled pressure relief events. Chemical Process Safety regulations in the United States and Canada mandate that companies constructing or operating chemical process facilities perform a rigorous hazard and risk analysis based on either ANSI/ISA-84.00.01 or IEC 61511 safety standards to determine the level of protection required for each hazard in the plant. This paper describes the application and implementation of three (3) unique safety instrumented systems developed by Hatch for ensuring the safe operation of three different pressure oxidation processes.

Jan 1, 2014

By A. J. Williams

"IntroductionAN EXCELLENT paper entitled Potash Discoveries in Western Canada (l) was presented to the 1948 Annual Meeting of the C.l.M. by L. Heber Cole, of the Department of Mines and Resources, Ottawa. In the intervening three and a half years, the search for oil and gas in Saskatchewan has added considerably to the information available on the occurrence of potash. It is the purpose of this paper to summarize the additional data. For greater clarity, it may be useful, first, to recapitulate some of the highlights of Mr. Cole's paper.Underlying the western plains of Canada there is a large deposit of sodium chloride, believed to be of early Devonian age. Associated with the sodium chloride are certain potash salts, primarily 'sylvinite,' a mechanical mixture of sodium chloride (halite) and potassium chloride (sylvite) crystals. The potash salts, when present, are usually near the top of the salt formation, though in at least one well they were found near the central part of the deposit. Cole reported on some seven wells in Saskatchewan which had encountered appreciable amounts of potash; these were the Ogema, Radville, Davidson Nos. 1 and 2, Prairie Salt Nos. 1 and 2, and Verbata wells. Depth of potash from surface ranged from 7,653 feet in the Radville well to a minimum of 3,466 feet in the Verbata well. Such depths do not compare favourably with those at which the potash is found in mines in the United States, France, and Germany, where about 1,000 feet is the average. The greatest concentration of sylvite encountered was in the Verbata well, where a bed 11 feet thick carried the equivalent of 21.64 per cent K20."

Jan 1, 1952

By Lawrence Bragg

WE associate metals with hardness, toughness, and strength. But a curious paradox lies at the root of the valuable mechanical proper-ties of the metallic state: in order to be strong, a metal must be weak. This paradox, and the equally surprising fact that, in a sense, metals are not true solids at all, are among the topics here discussed by Sir Lawrence Bragg. (1) WHAT METALS MEAN TO US We employ various materials to build or fabricate the many objects we use in everyday life, choosing those whose properties are most suitable for the purpose which the object has to serve. Certain of these materials have been used from the earliest times, such as stone, wood, leather, and animal or vegetable fibres, each with its own peculiar valuable properties. Stone resists crushing and is very durable and permanent, as indeed it must be, since it has so long resisted change as a part of-the earth's crust. It is there-fore ideal for walls and buildings, and very early in his history man discovered how to make artificial stones by burning clay, with the advantage that they could be given any desired shape, and made into bricks or given elaborate forms as pottery. Wood is strong and tough and light, it resists tension as well as compression, and is nor brittle like stone. It forms beams and furniture and parts of tools or weapons. Leather is tough but at the same time iris flexible; it is ideal as straps or sheers. Vegetable fibres such as linen or cotton, and animal fibres such as wool and silk, owe their value to their flexibility and strength in resisting extension. They can be spun into yarn or rope, and woven into cloth. The technological age in which we are now living is replacing the natural products used by early man by a series of artificial products, but it is remarkable to see how in nearly every case we are copying Nature's materials. The wide use of concrete represents a developed art of making artificial stone. Artificial fibres such as rayon or ?nylon replace cotton, wool, and flax. Plastics are coming very much to the fore; they correspond to early man's use of horn, another substance with peculiar properties of roughness in all directions without the 'grain' of wood. For the most part we are following in the footsteps of our remote ancestors, though we can make for ourselves what they had to cull from wood and field. There are exceptions; for instance, we have discovered comparatively recently the number of uses to which natural rubber can be put, and are now making it artificially. This is a really new discovery; our ancestors had nothing with such remarkable powers of elastic stretching without breaking, and resistance to being abraded.

Jan 1, 1943

By The Staff

"IntroductionThe difficulties to be overcome in shaft sinking and development at depth are centred at McIntyre in and around No. 12 shaft. Generally they have been due to increasing pressures and temperatures and to changes in geological structure. This paper describes the difficulties and the measures taken to meet them.No. 12 ShaftEarly in 1932 McIntyre decided to sink an internal shaft from the deepest level, the 3875, to explore and develop known veins extending below that horizon. The location selected was a point 1,500 feet south and 1,000 feet east of No. 11 shaft, the main operating shaft through which the men, ore, and most of the materials are handled Shaft and auxiliary equipment we1e laid out for 3,000 feet, that is to 7,000 feet below the surface. The shaft was to be capable of handling 1,500 tons of ore daily from the lowest level, and was to provide ventilation, compressed air, water, and electric power to service all levels.No. 12 is an internal, vertical shaft extending from the 3875 to the 6825 level and bottoming at 7,007 feet. It is a rectangular, four-compartment shaft, 21 ft. 9¾, in. by 6 ft. 3¾ in. outside the timber (Figure 1).There are two hoisting compartments and one airway compartment, each 4 ft. 10¾ in. by 5 ft. ¾ in. inside dimensions, and a combined manway, pipe, and cable compartment 4 ft. ¼ in. by 5 ft. ¾ in. Levels have been established at 150-foot intervals, pump stations and sumps at 1,000-foot intervals, and. there are two loading pockets, one at the 5525 and the other at the 6900 level.The shaft was sunk in two stages. The first stage, consisting of preparation above the 3875 level and sinking to 5585 feet, was completed by March 31st, 1935. The second stage of deepening the shaft from 5,585 to 7,007 feet was started August lst, 1946, and completed three years later."

Jan 1, 1950