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By M. M. Williams

ALBERTA has been generously endowed with oil, natural gas, coal and water power, thus giving power producers a wide choice in the type of plant and fuel which can be used. Therefore, with such a variety of energy sources to choose from, why was coal selected as the primary fuel at Calgary Power's Wabamun steam plant? This part of the paper will cover the circumstances that led the Company to decide in favour of coal. The second part, to be presented by C. F. Doerr, will describe how the Wabamun coal mine has been developed to supply the large fuel requirements of the power plant. Before considering the Wabamun plant, we require a general under-standing of? the Company's electric system and load. Power is fed into a 5,100-mile high-voltage transmission grid from eleven hydroelectric plants and from the Wabamun steam electric plant. These plants have a combined generating capacity of 820,000 horse-power. Of this total, the hydro

Jan 1, 1963

By J. P. Morgan, D. B. Stewart

"AbstractLoad-haul-dump machines equipped with. a torque converter and hydraulic pumps have been field tested by means of an engine monitoring instrumentation package. It was found that owing to parasitic losses in the ancillaries and drivetrain, maximum available useable pourer may peak at less than full engine speed. Simple reduction of engine speed may save 15 to 25 percent on fuel consumption, with no significant loss of available power. On some machines, speed reduction will require modification of the torque converter . The cost of this modification, when necessary , would be offset by reductions in exhaust emissions, ventilation requirements, fuel consumption , heat, noise and hydraulic system maintenance, and by increased life of rotating components and filters and machine availability.IntroductionTHE CANADIAN EXPLOSIVES ATMOSPHERES LABORATORY, in conjunction with Deutz Canada Limited, has designed, constructed and field tested a portable instrumentation package. This package monitors diesel engine performance in underground mining machinery by continuously recording engine speed and volumetric fuel delivery. During tests designed to determine the engine load and speed conditions for the various segments which constitute actual underground operation of a Deutz F6L 714-powered 4-yard load-haul-dump machine, it was discovered that an unexpectedly large percentage of the engine power was required to overcome the ancillaries and drivetrain drag (1). That this large component of engine power is functionally related to engine speed rather than the operator's needs was verified by repeat tests of the used 4-yard machine and by testing of a new 5-yard machine powered by a Deutz F 8L 714."

Jan 1, 1977

By Horace Freeman

"IN THE writer's opinion, the most important industrial re-search problems in Canada concern development of technology for the treatment and commercial utilization of the recent discoveries of v.ast quantities of easily concentrated iron ores in both eastern and western Canada. They exist in both magnetite and hematite forms. The subject is doubly important because of the lack of metallurgical coking coal in Canada. Methods for utilizing our lower grade eastern and western coals for reduction purposes must be developed. We are fortunate in our supplies of oil and gas, which can supply the heat requirements for processing or for thermal electric plants, which are now competitive with hydro-electric plants in the industrial areas. These are among the reasons which have prompted the writer to continue the development of the co-current rotary kiln direct-reduction process outlined •in his report to this Institute at the 1956 Annual Meeting ( 1) in the face of the scepticism which has surrounded the numerous costly failures in 'sponge' or 'direct' iron production. The work involved in bringing the concentrating ores of Canada to the metallic state involves, firstly, concentration of the ores; secondly, preparing the concentrates for reduction; thirdly, reduction of the 'reconstructed' ore; and finally the steel making process. These briefly will be dealt with in order, giving emphasis to the most important of these steps, the reduction process which is the main subject of this paper."

Jan 1, 1959

By A. Ignatow

"A review is made of some of the principal factors and conditions that are, and will be, important to the over-all market climate for asbestos fibre and for the future of Canada's asbestos industry: - health hazard associated with asbestos exposure;- uncertain international regulatory environment for continued asbestos use;- adverse public reaction to asbestos;- product liability/litigation costs (U.S.A. primarily);- promotion of substitution by governments and asbestos user industries; and- minimal product and market development efforts by asbestos producing and consuming industries.In addition, Canadian producers, who export some 95 per cent of their production, face additional constraints:- dramatically reduced integration with asbestos-consuming industries;- 60 per cent of exports to most rapidly declining markets (U.S.A., Europe);- increased competition from offshore producers favourably located to growth markets in developing countries;- increasing production costs;- a strong dollar;- disadvantageous freight rates; and- loss of price leadership and price erosion.Future market trends, as well as prospects for Canada's asbestos industry, will be projected in this paper.Economic FactorsTable 1 presents asbestos fibre production in all countries for the period 1980-82. In certain instances, e.g. U.S.S.R. and China, these are capacity estimates as production statistics are not officially published. The U.S.S.R, by far, is the world's largest producer accounting for some 50 per cent of world production, though most production is consumed internally or by COMECON countries. It is estimated that some 700 plants produce asbestos-containing products within the U.S.S.R.Canada accounts for some 25 per cent of world production though it ranks first in world trade. Other important producers are South Africa Zimbabwe, Brazil and Italy. Since 1979, Canada's asbestos mining industry has experienced a dramatic drop in production and exports of asbestos fibre, as demonstrated in Table 2."

Jan 1, 1985

By Brian G. Pewsey

Located in the northern part of the Province of British Columbia, the Cassiar Mine started development of its asbestos orebody in 1952, and is currently producing 105.000 tons of asbestos fibre annually. The townsite is nestled in a beautiful valley and supplies more than average facilities. The fibre is shipped to more than 40 countries and is used in many industrial products.

Jan 1, 1978

By K. D. Genn, A. Mucha

This paper deals with Hilton Mines' approach to the maintenance of wear items such as truck boxes, shovel buckets, tractor pads, crawler sprocket idlers and the drop-ball. Each will be given a brief. description as to application, design, kind of materials involved and type of wear. The maintenance procedure is then outlined in terms of materials used, preliminary preparation, and welding and machining practices. The service history of new and re-paired items and the relative economics of repair vs replacement will then be presented.

Jan 1, 1969

By Antonius Prayoga

PT Smelting adopted the Mitsubishi Continuous Technology for its copper smelter plant which has been operating since 1998. Through a series of expansion projects, the plant annual production capacity increased gradually from 200,000 to 300,000 tons of copper. There were no significant modifications for the smelter to reach the 50% additional capacity. It was mostly achieved by intensifying the operation of the furnaces by increasing the oxygen content in the furnaces blowing air. Intensive smelting furnace operation caused shorter campaign life of some furnace refractory, especially the melt zone wall on furnace outlet. During each furnace relining, which is done once every two years, severe wall erosion was found. The worst condition occurred in 2007 when the smelting furnace experienced a melt leak through the eroded wall beneath the bath-line coolers. During the 2008 furnace relining, a modification was performed by installing vertical coolers behind the melt zone wall. Additional vertical coolers were installed during the 2012 furnace relining to extend the coverage area. The modification improved melt zone wall integrity significantly by keeping them safely within the two year campaign life. Recently a modeling study was done to estimate the influences of molten waves on furnace wall erosion. The aim of the study was to predict the impact of blowing parameters, such as blowing air velocity, on the melt wave character and wall erosion.

Jan 1, 2015

By S. Dominguez, E. Gebrehiwot, S. Richardson, S. Sandoval

Copper electrowinning/electrorefining (EW/ER) is powered by direct current (DC) rectifiers that typically generate 30,000 to 70,000 amps and a bus-bus voltage of 200 to 500 volts DC. Tankhouses are designed so that DC current flows through “cell lines” which contain individual EW/ER cells electrically connected in series. Electrolyte composed of copper sulfate and sulfuric acid in water forms the “liquid conductor” that connects the metallic conductors in this circuit. In this setting, stray current is a DC current that strays from and therefore bypasses the tankhouse circuit by finding a path to ground, often through the electrolyte in pipelines that feed into and discharge from the cells, or through dried electrolyte (i.e. sulfate), which is also electrically conductive. Tankhouse workers can be exposed to shock hazards if they become part of a stray current path to ground. This presentation details examples of stray current shock hazards in electrolytic tankhouses and provides voltage and amperage measurements associated with stray current in these examples. A review of critical safety controls in EW/ER tankhouses that will mitigate the risk of employee shock from stray current is also provided. INTRODUCTION Electrolytic tankhouses are designed to deliver relatively large amperages of DC current to a series of electrolytic cells in which copper is plated out of solution using the classic anode-cathode pair geometry within each cell. Electrolyte is the “liquid conductor” that transfers current in between the metallic conductors of the cell. The metallic conductors include inter-cell copper bus bars and the anodes and cathodes themselves. It is sometimes forgotten that electrolyte as a conductor is capable of delivering DC current outside the designed circuit of a tankhouse. Stray current is a DC current that strays from the tankhouse electrical circuit by finding a path to follow other than the designed path. Safety becomes a concern when there is a risk of an employee becoming part of an accidental stray current path, thereby suffering an electrical shock. In 2016, Freeport-McMoRan (FMI) suffered a fatality at one of its copper electrowinning tankhouses. The forensic analysis concluded that stray current from the tankhouse rectifier contributed to the fatality. An employee accidentally fell into contact with a metal flange at the end of an HDPE pipe that was collecting cell overflow electrolyte from the tankhouse. DC current passed through the employee to ground, creating a shock that was judged to contribute to his death. The situation was exasperated because the employee was unconscious, and therefore was exposed to the stray current for several minutes before being found. In addition, the employee’s clothing was saturated with liquid, and the employee was found kneeling in puddled liquid on the ground. FMI immediately began an investigation into the root cause of the stray current that was measured at the scene. Sufficient electrolyte had accumulated in the HDPE pipe such that a continuous path was formed between it and electrolyte that was continuously overflowing from energized electrowinning cells. The metal flange on the pipe was the metallic conductor that carried the current to the employee from the electrolyte inside the pipe. Current then flowed through the employee to ground. Because of this incident, FMI undertook an extensive review of the hazards of stray current in EW/ER. FMI’s tankhouse workforce received a Tankhouse Electrical Safety training course developed in- house to insure worker understanding of stray current hazards. Tankhouse design changes were implemented to better insulate workers from stray current. Personal protective equipment (PPE) standards were also reviewed and changes made.

Jan 1, 2019

By D. Markwart, B. Volk

Anode effects are a phenomenon of the aluminium electrolysis process which produce potent greenhouse gases called PFCs (CF4, C2F6). With concerns surrounding global warming, and increasing regulation of GHG emissions, anode effects have become a significant sustainability issue for aluminium producers. In modem smelters, sophisticated computer control and automated alumina feeding systems allow for very tight control of the alumina concentration in the electrolyte and thus very low anode effect frequencies. Older smelters, however, do not have these systems and must either invest heavily to obtain them, or find other, innovative ways to reduce anode effect frequency. This paper will present the integrated approach to anode effect reduction used in the Vertical Stud Soderberg (VSS) potlines at Kitimat Works. Through an innovative combination of simplified signal analysis, modified alumina feed control logic, anode effect prediction, and anode effect prevention using a pager based communication system, Kitimat W arks has been able to make significant reductions to its anode effect frequency.

Jan 1, 2006

By B. Wasmund, M. Parravani, M. Jastrzebski, Z. Coull

"One of the main drivers of overall profitability of pyrometallurgical vessels is refractory lining campaign life. Increased economic pressure to improve vessel life requires innovative solutions to the problem of refractory cooling. Hatch has recently developed a high-intensity, waterless cooling system that bridges the performance gap between external shell cooling and internal water-cooled copper elements. External shell cooling has a limited effectiveness in protecting the refractory lining, because it is thermally insulated from the hotface of the lining by its thickness. This situation does not improve until the lining itself has become worn near the end of the campaign. The patented technology developed by Hatch overcomes this problem by positioning high-velocity air-cooling channels within the lining, closer to the hotface where the cooling benefits can be realized throughout the entire duration of the campaign. The current paper presents the development and application of Internal Air Cooling technology as well as results from the pilot campaign in an operating commercial vessel. Various adaptations for this novel, cost-effective and inherently safe system are also discussed."

Jan 1, 2015

In this study, flotation of fine galena, chalcopyrite and pyrite was performed after grinding with different extent of oxidation-reduction condition adjusted by grinding media. Sodium dithionite and iron ions were added in mill to simulate pulp potentials and iron oxidation species produced by grinding media, respectively. The types and quantities of the metal oxidation species on mineral surfaces were determined by EDTA extractions, while the surface electrical properties of minerals and interaction of different types of metal oxidation species were studied by zeta potential measurements. It was found that the nature and concentration of the absorbed metal oxidation species were dependent on oxidation atmosphere controlled by the iron amount of grinding media. These species interacted with each other and had an important role in determining flotation of fine galena and chalcopyrite as well as activation of fine pyrite by lead and copper.

Jan 1, 2006

By J. R. Dinn

On the afternoon of Saturday, June 23rd last; there was an unusual occurrence at the surface plant of the Dominion Coal Company's Caledorria mine, Glace Bay, which operates on the Phalen seam, here lying at a depth of 170 feet from the surface. On that day, the writer, who was attending a business conference in the General Office about a mile distant from the Colliery, received a telephone call to the effect that there was a strong odour of gasoline or kerosene in the wash-house and lamp-house of the Colliery, and that the attendants in both the wash-house and the lamp-house had become ill and had had to be sent home. Instructions were given at once to cut off the electric current, and to close all doors to prevent access to the building. When the writer arrived at the plant and questioned the workmen, he was led to the belief that the gasoline tank in the lamp-house (used in connection with flame safety lamps) had leaked and that the gas, having volatilized, had displaced sufficient oxygen to cause the trouble. Emphasis was being placed on the kerosene, or, as some said, the gasoline, odour. In the lamp-house, there is a small shuttered window which opens on a corridor. Here the workmen receive their lamps from the lamp attendant. An examiner, with a flame safety-lamp, proceeded to test the atmosphere within the building by passing his lamp through the open window, since, if the trouble was due to volatilized gasoline, a gas cap would be shown on the flame of the safety-lamp. After holding the lamp for a few seconds inside of the window, he withdrew it and remarked, "There's no gas cap" . Almost immediately the lamp fell from his hand and he dropped unconscious to the floor of the corridor. The writer, who was standing beside him, felt no ill effects and removed him at once from the corridor. Steps were immediately taken to revive him ( artificial respiration) , and in about ten minutes he became conscious and was breathing naturally. In making the examination, his head was not inside the window, but in line with the frame of it. It was apparent that some gas more deadly than the hydrocarbons from gasoline was present.

Jan 1, 1934

By Louis Frost

"Dominion No. 17 Colliery, of the Dominion Coal Company, Limited, is located in the district of New Victoria, N.S., at the entrance to Sydney harbour.This Colliery was opened in 1882 to work a submarine area of the Harbour seam (see Figure 1). It was closed in 1921 and the mine, which has a make of water of approximately 250 gallons per minute, was allowed to fill.No. 18 Colliery, situated almost a mile to the east, was opened in 1938 to work the Phalen seam in this area with the intention, later, of driving a cross-measure tunnel to mine the section of the Harbour seam lying between No. 17 Colliery and the Princess Colliery of the Nova Scotia Steel and Coal Company, Limited.In 1945 it became necessary to open this area in the Harbour seam and a cross-measure tunnel was driven from the existing workings of No. 18 Colliery in the Phalen seam, which underlies the Harbour seam at a depth of 500 feet.The tunnel was started in 1946 and completed in 1948. The cost of opening this section, which contained only 6 1/2 million tons of coal, made imperative the recovery of all the available coal and precluded the maintenance of the large barriers that had been left in No. 17 Colliery for impounding the water, especially as the maintenance of these barriers would have meant the loss of 885,000 tons of coal, or 12.3 per cent of the whole tonnage available. Therefore, a study was made to determine the best means to dewater the 250 million gallons of water lying in the old No. 17 Colliery."

Jan 1, 1952

By Suzie Nantel

Crystalline igneous rocks, known commercially as granite, are exploited in Quebec f rom more than twenty-five quarries for building, ornamental and monumental purpose$. Quebec is the main Canadian producer of construction granite, accounting for nearly 90 per cent of total production. Jn the last three years, this industry has experienced an important growth due to improved marketing and use of modern equipment in rock-cutting and polishing. Jn /983 a 35 per cent sales increase is forecast. The main rock varieties extracted are the following: porphyritic pinkish grey granite and green charnockite from Riviere-dPierre, mahogany brown granite and black anorthositic rock f rom the Lac Saint-Jean area, fine-grained pink granite from Guenette, coarse-grained brown quartz monzonitefrom SaintA lexis-des-Monts. All these rock types occur in the Grenville tectonic province whereas a medium-grained, light grey granite, Devonian in age, is extensively being quarried in the southern part of the Appalachians. In the Superior province a greenish black diabase and a deep red granite are extracted. Search for new varieties and deposits is actively being carried out by prospectors and by the minis/ere de /'Energie et des Ressources du Quebec following growing demand for granitic and gabbroic rocks as dimension stone.

Jan 1, 1984

By Victor F. Hollister

Elemental sulphur occurs as aformational sedimentary deposit in Upper Devonian Wabamun evaporites near Coronation, Alberta. The deposit developed in a stratigraphic jacies-change lrap; it is assumed that petroleum reacted with anhydrite to form sulphur, calcite, hydrogen sulphide and other reaction products. The deposit contains about 362,800 tonnes of sulphur and lies at a depth of 1200 m. The Coronation deposit is expected to be geologically typical of such other native sulphur deposits as may be found in Wabamun Group sediments. Widespread sour gas sulphur production f rom the Wabamun suggests the possibility that additional native sulphur deposits will ·be found.

Jan 1, 1984

By Stewart W. Daniel

"Increasing labour costs, the trend to larger mills, the processing of lower grade ores and a diminishing sup-ply of well-trained and experienced mill operators contribute to the necessity of automating a grinding circuit. With sophisticated process control techniques, supervision of the mill line is reduced to an occasional inspection by the shift supervisor. Process operating decisions and/or adjustments are quickly and accurately performed by the electronic devices to be described. When the variables in the grinding circuit are stabilized using the sensors and controllers as discussed, the over-all grinding circuit is maintained at its optimum grinding load level, with ample protection against under-and overloading."

Jan 1, 1967

By Y. Masuda, Y. Nakamura, K. Haraguchi, A. Taniguchi, K. Arita

Availability of the elements originating from steelmaking slag for various marine phytoplankters including purely cultured strains and natural populations was tested in land and shipboard laboratories. The results obtained demonstrate that, although their solubility was not uniform among different slags, dissolved iron, silicate and phosphate from the slag stimulate phytoplankton growth. No negative effect of the slag addition on their growth was observed at lower dose, e.g. less than 200 mg/l. Since most coastal waters are the hypernitrogenous environment due to anthropogenic load of ammonium, the slag can be an ideal source of silicate and phosphate, which restore the hyper-nitrogenous condition into truly eutrophic condition with balanced Redfield ratio. In so-called HNLC (high-nitrate low-chlorophyll) oceanic areas such as the Southern Ocean and the subarctic North Pacific, where iron is almost only limiting factor of the phytoplankton growth, the slag could also be a source of iron and enhance CO2 fixation by phytoplankton photosynthesis. (Key words: carbon deposition in deep-sea, marine environmental remediation, phytoplankton, slag as a source of iron, phosphate and silicate.)

Jan 1, 2004

By Shuo Zhang, Wenying Liu

"In dump leaching, the efficiency of metal extraction from ores is strongly influenced by the mechanisms of fluid flow. Particle size distribution acts as a fundamental parameter in the determination of fluid flow properties in packed ore beds. In this study, we investigated the particle size distribution in dump leaching by using image analysis technique. The results showed that the particles in the dump varied from smaller than 2 cm to larger than 200 cm in diameter. P80 was calculated to be 200 cm, which was significantly higher than the historical data used by the operation. P25, P50 and P80 were found to increase non-linearly with increasing depth towards the toe of the dump, suggesting the segregation of fine and coarse particles. The image analysis results were verified by applying the rock fragmentation models. The model with the Swebrec function was found to be in better agreement with the image analysis results. Future research will investigate the effect of particle size distribution on the behaviour of fluid flow.INTRODUCTION Fluid flow plays an essential role in the extraction of valuable metals using heap/dump leaching (Amos et al., 2009). The rates of the chemical leaching reactions and microbial activities determine metal concentrations in the leachates and therefore the efficiency of the metal extraction. The reaction rates are influenced by two fundamental processes: transport phenomenon and reaction kinetics (Bouffard & Dixon, 2001). The transport phenomenon refers to the percolation of fluids through channels and pores in a packed ore bed, which carries lixiviants and reaction products to/from ore surfaces by convection and diffusion. The percolation rate of the leaching solution is determined by the hydraulic conductivity of the packed ore bed, which is a function of the permeability and the degree of saturation (Guzman et al., 2008). Permeability, an intrinsic property of a packed ore bed, is strongly influenced by the particle size distribution of the ore grains (Bouffard & Dixon, 2001). Hence, the objective of this study was to investigate the particle size distribution in dump leaching."

Jan 1, 2017

By A. R. Khodabandeh, T. Nematkhah

Correct selection of forging parameters is very important to produce sound superalloy parts. In this investigation nickel-iron base superalloy IN901 successfully forged and seal spacer, which is a part of airplane with about 11 kg weight has been produced. Forging has been performed on the basis of hot compression results, which show deformation above 1100°C associated with dynamic recrystallization (DRX) which can increase the workability of material. On the other hand annealing at 1100°C decreases the flow stress during hot compression, and then increases the material formability. Then billets annealed at 1100°C in electrical furnace for 24 hours and reheated again to 1100°C before forging. Initial square cross section billet with 128mm side and 202mm length forged immediately after reheating by 80MN mechanical press. Specimens forged in five steps: upsetting, three steps molding and finishing. Preformed and molded specimens reheated in electrical furnace before later step of forming. Finally specimens trimmed by 1 OMn mechanical press and hot set by hydraulic press and then cooled in air to room temperature. Results show that reheating temperatures has been selected correctly because there isn't any surface crack and die cavities filled completely by forging material. Material flow has been carried out properly and there isn't any defect in critical points especially in extradoses and intradoses. Microstructural examinations show that grain boundaries contain Ti-rich globular particles that formed during cooling.

Jan 1, 2006

By Claude Bourgoin

"The Copra massive sulphide deposit occurs as a continuous slab of ore dipping at approximately 40 degrees within a sericite schist formation. The orebody has been delineated over a distance of more than 5,000 feet down dip. This paper is mainly concerned with the mining procedure, and particular reference will be made to the use of steel mill holes and hydraulic roof supports. The gravel backfill line, which is operated both by gravity and hydraulically, is described. The paper mentions some of the operational problems, discusses the feasibility of longwall mining and presents the information obtained from stope testing."

Jan 1, 1966