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By P. E. Cavanagh

THE Ontario Research Foundation has developed a family of dry magnetic concentrators which, when used in conjunction with a dry grinding mill such as an Aero-fall mill, will allow the production of a completely dry magnetite concentrate. Previous experience with extrusion of iron ore and with pelletizing of fine iron concentrates suggested that it might be possible to develop a method particularly suited to the agglomeration of completely dry concentrates which might have some practical advantages over other methods of agglomeration. Pelletizing is the preferred method of agglomerating very fine iron ore concentrates. Magnetite concentrate is fod to the pelletizing equipment in the form of a moist filter cake. Binders and plasticizers may be added if necessary, and the moisture content must be increased or adjusted to the percentage necessary to give good balling action and satisfactory green strength in the resulting moist pellets. The moist ore with a closely controlled water content of about 7 to 12 per cent moisture may be rolled into pellets by a snow-balling action in a pelletizing drum, a Lurgi pan, or a Mac-Dowell disc pelletizer. The resulting green pellets are fired by one of several alternative processes to produce a hard pellet which has sufficient strength to withstand handling and shipping.

Jan 1, 1957

By James D. Hall

THIS essay deals with the materials and methods used in the waste filling of scopes in Canadian mines, with especial reference co the methods used at the Sullivan mine, Kimberley, B.C. The author would like to thank members of the staff of the Sullivan mine for information obtained, and acknowledges material from the following publications: Waste Filling of Stopes: Information Circular 6816, U.S. Bureau of Mines. Mining Methods and Practices at Lake Shore, by Leslie S. Weldon; Trans., C.I.M. & M., Vol. XXXIX, 1936, pp. 142-202. Development and Mining (at the Mcintyre Mine), by D. E. Keeley; Eng. & Min. Journal, November, 1933. INTRODUCTION Although mining in Canada is a relatively youthful industry, many of our mines have reached a stage of extraction which requires waste filling, both as a means of support and co make possible the winning of ore that would otherwise have co be left in the mine. Fill may be used at regular intervals as one of the cycle of operations, as in cur-and-fill and square-set scoping; or it may be introduced into a completed stope co provide permanent support for overlying rock formations, and co permit mining of pillars of valuable ore. Waste fill is sorted in resuing, which is a form of cut-and-fill scoping employed in narrow veins.

Jan 1, 1937

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 W. R. McClelland

GOLD-BEARING ores, representing many types, are found widely distributed through the Province of British Columbia. They range from those which by their nature may be considered as complex, to those whose mineral characteristics are simple. Those in which the gold is associated with metallic sulphides provide particular milling and metallurgical problems, the solution of which involves not only detailed laboratory investigation but also a careful consideration of economic factors. The location of an ore-body may have a deciding influence on the adoption of a method for the metallurgical treatment. Whether the ore should be treated with the object of recovering the gold as bullion or as a shipping concentrate is often dependent on such topographical considerations as the position of the mine at or near tidewater or within a reasonable overland distance of a smelter. British Columbia is fortunate in having the Trail smelter situated in the southern part of the Province, and the smelter at Tacoma, Washington, is accessible for coastwise traffic. Both of these provide a ready market for most types of gold-bearing concentrate. In order that the results obtained by laboratory tests may give a fair indication of what should follow in mill operation, it is essential that the test sample should represent as closely as possible in mineralogical character and in grade the ore that eventually will constitute the feed to the mill. In the early stages of mine development this consideration is sometimes overlooked and samples of a much higher grade than would be representative of run-of-mine ore are submitted. Flotation tests on such a sample of ore high in sulphides may show a low ratio of concentration, bu.t if the actual run-of-mine ore is lower in sulphides the mill operation will reveal a much higher ratio. The recommendations for treatment based on the results of laboratory tests may have been against concentration, when in actual operation this would be the most suitable method of treatment. Recommendations based on laboratory tests are necessarily from the results of work carried out on the sample submitted, modified only by such other economic or topographical information as may be known to the investigator. This paper deals with a few of the gold ores found in the six mining districts of British Columbia and is based on investigations made in the Ore Dressing and Metallurgical Laboratories of the Mines Branch, Department of Mines, Ottawa.

Jan 1, 1937

By Ian M. F. Arnold

"Occupational health programs and their role in improving the quality of working life in the mining industry are discussed. Attention is directed to some problems peculiar to the Canadian mining industry. Factors affecting program development are reviewed, as well as parameters affecting cost-benefit analyses.IntroductionThe quality of working life in the mining industry is a more important consideration than in many other industrial environments because of the very nature of the undertaking. It was a strange paradox of the 1960s that preventive maintenance programs for machinery and equipment were well accepted, whereas the concept of ""preventive people medicine"" was basically ignored. Fortunately, there seems to be a swing toward the development of occupational health programs in many sectors of the business community; however, there is a noticeable lack of consistency and uniformity for thought among the members of the mining industry. The blame for this lack o f progress in the occupational field cannot be entirely attributed to the industry, but must also rest with (for the most part) apathetic and inadequately trained physicians. This latter problem is slowly improving with the growing recognition that a well-planned and executed occupational health program may improve the quality of working life for mining employees and their families.There are a number of factors which relate to occupational health in mining, and its effect on working life quality. Included among these are:1. Community isolation.2. High accident risks.3. Occupational disease risks.4. Production demands and the state of the economy.5. Government regulatory requirements.6. Travel demands.These, and others, reflect on all levels of the mining industry. To examine how these factors can be moderated by an occupational health program, it is necessary to first review the rationale for such a program and some of the costs related to it."

Jan 1, 1983

By D. T. White

"Metallurgical extraction processes often call for the heating of aqueous slurries. Indirect heat exchangers are generally not feasible for service with high yield stress slurries because of low heat transfer rates. It is more appropriate to heat the slurry by direct contact, typically with steam as the heating medium. Although having a long and successful history, direct-contact heat transfer to aqueous slurries has been used without the support of pilot plant research. This paper provides results of the needed research, the work being done at a scale large enough to enable direct scale up to commercial operations. A pilot plant heater was constructed and tested to develop an understanding of the slurry heating process and to ensure that commercial scale heaters were appropriately sized.INTRODUCTIONPressure Leaching OperationsPressure leaching operations are often used to oxidise sulphide gold ores, or for extraction of nickel and cobalt from laterite ores with sulphuric acid. Where there is sufficient sulphur available, the exothermic pressure oxidation reactions can be self sustaining at temperatures as high as 225 ºC, without having to preheat the feed slurry. At lower sulphur levels, slurry preheating is required. This is typically achieved by utilising the flash steam released from the slurry letdown stages and contacting this directly with cold incoming slurry ahead of the autoclave. The vessels where this slurry-steam contact is made are known as heaters or condensers, with the number of pre-heat stages varying, depending on how much heat is evolved in the oxidation reaction (Mason, 1990).In nickel laterite pressure acid leaching processes, which operate between 245 and 270 ºC, the only significant exothermic reactions are those associated with dilution of sulphuric acid in the leach. As a consequence, slurry preheating with flash steam is always used commercially. In practice the number of flash steam preheating stages required varies from 1 to 3, driven by a number of factors, including other uses for flash steam and the upper temperature limit at which preheated slurry can be pumped. A diagram of a typical pressure acid leach train is shown in Figure 1.For pressure acid leaching operations and at low sulphur levels in pressure oxidation, boiler generated direct steam addition to the autoclave is required to sustain the reaction temperature. For this reason it is imperative that the flash steam – slurry heat transfer is efficient and the slurry temperature approaches that of the flash steam closely."

Jan 1, 2012

By A. E. Wraith, R. Harris, J. Qiu, R. Parra

Small pilot scale experiments have shown that it is possible to almost fully eliminate the minor elements (ME), namely As, Sb, Bi and Pb contained in smelter dusts by vacuum calcination of mixtures of the dust with sulphidizing agents such as dirty copper concentrate or elemental sulphur at 900 °C and 80 +/- 30 Pa for 90 minutes. The products of this calcination are a residue comprising a purified mixture of copper containing compounds along with the gangue constituents and a high sulphur condensate comprising a mixture of the minor element compounds. In particular, the Cu:ME ratios of the concentrate and dust were increased from 250 and 50, from 28 and 12 and from 36 and 8 to roughly 3000, 3000 and 100 for the calcine, for Bi, As and Sb, respectively. It has also been calculated that (i) the copper content of the vacuum calcine may be recovered by feeding it into a Peirce-Smith converter during its slag blow, and (ii) the resulting recycling could increase the minor element treatment capacity of a smelter by 100 % while also reducing the blister As content by a factor of three. The experimental results are briefly discussed and a treated dust recycling option is examined. Example operating conditions are presented and available commercial technology for the vacuum calcination of the mixtures is reviewed.

Jan 1, 2007

By N. Parnian

"Carryover of caustic soda (NaOH) in the steam path caused catastrophic failure of superheater 304H stainless steel tubes in a steam generator and led to an unexpected shutdown after just five months of continuous service of petrochemical following the start of production. The cause of the failure was studied, with a focus on the formation of sigma phase in the weld joint and effect of caustic embrittlement on stress corrosion cracking (SCC). The cracks were examined at the seam weld, heat affected zone (HAZ), and Ubend areas. Hardness was measured for the base metal, HAZ, and weld metal, and microstructures were examined using optical microscopy and scanning electron microscopy (SEM). Crack initiation is attributed to gouging on the precipitated carbide at the HAZ and also the formation of sigma phase in the weld metal, as shown by energy dispersive X-ray (EDX) analysis. In addition, cracking was propagated by caustic embrittlement because of residual stresses and hammering. Finally, the characteristic feature of fracture was illustrated by SEM fractography, and consists mostly of intergranular SCC and some quasicleavage transgranular. INTRODUCTIONThree key factors are needed for the initiation and propagation of intergranular stress corrosion cracking (IGSCC): a susceptible material, a corrosive environment, and sufficient stress. Although austenitic stainless steels are susceptible to sensitization and IGSCC, they are widely used in boiler and superheater tubes because of their high corrosion resistance, high oxidation resistance, acceptable mechanical characteristics at elevated temperatures, and low cost.Sodium hydroxide is injected to neutralize acidic constituents in the steam path, but caustic can concentrate in boiler tubes and attack the surface metal (known as gouging) even traces of caustic in the steam can deposit on surfaces and cause local concentrations of several percent (ASM handbook, 1992). Not only sensitized grains but also sigma phase formed in the weld metal can initiate caustic cracking. In this research, the cause of the failure of 304H stainless steel superheater tubes in a methanol petrochemical plant in Iran was studied with a focus on the effects of caustic embrittlement on IGSCC."

Jan 1, 2012

By Michel Dostie

Un séchoir à vis chauffé par induction électromagnétique a été développé et implanté chez Mines Niobec pour le séchage d?un concentré de niobium. Ce séchoir a permis une réduction des émissions de poussières et des gaz à effet de serre de l?usine. Il offre une grande souplesse de contrôle, une meilleure efficacité énergétique et peut être utilisé pour le séchage de granulats, de poudres ou autres substances habituellement traitées dans un four rotatif ou à l?aide de vis chauffées par un caloporteur. Le principe de fonctionnement du séchoir est simple. Trois inducteurs opérant à la fréquence du réseau électrique assurent le chauffage des parties métalliques du séchoir, dont des vis qui servent à convoyer le matériel. Le contact du matériel avec les parties métalliques chaudes permet le transfert de l?énergie requise pour le séchage. La conception de ce type de séchoir requiert un équilibre adéquat entre les besoins associés au chauffage par induction et ceux liés au transfert de chaleur par contact et au transport du matériel dans le séchoir. Cette première implantation industrielle a nécessité des efforts de développements importants et une collaboration des différents intervenants. Une revue des principes de conception, des difficultés rencontrées et des performances obtenues sera présentée.

May 1, 2007

By J. A. Herbst

Professor Klaus Schönert and his students used fundamental physics to develop many of the principles required for the design and scale-up of "Gutt Bett Zerkleinern" devices such as the high pressure grinding roll (HPGR) or the high pressure roll crusher (HPRC). As the equipment evolved so have the tools used for its selection and analysis. In the current paper discrete element modeling (DEM), Metso's proprietary Fast Breakage simulations, and Schönert's packed bed piston test are combined with energy based population balance models (PBM) to yield an alternative to ore characterization and equipment selection by pilot plant testing. The resulting methodology is used to take the next step in understanding these devices with a view toward predicting plant performance. This paper describes a journey beginning with precise modeling of a small HPGR including stud geometry and system hydraulics. A key to predicting performance is the accurate modeling of individual particles, their motion in the machine, the probability of breakage and redistribution of fragments, and the inter-particle breakage events that occur between the rolls at different pressures, speeds and moisture levels. Advanced DEM simulations and particle breakage characterization methods provide the necessary technology. The resulting combined models were validated using a small diameter laboratory scale unit. The validated physics based model was used then used to predict the performance of plant scale units using a specific energy based scale-up method. Scale-up results are analyzed in terms of power draw, throughput, and discharge product size distribution.

Jan 1, 2012

By M. F. Goudge

This paper is intended to call attention to the manifold uses of limestone in industry; to indicate the types of limestone desired by some of the large consuming industries; and to give some information on the resources of limestone in Canada, so that an idea may be obtained of the present and future possibilities for limestone production. The word limestone is used in the usual broad sense to include both high-calcium limestone and the highly magnesian variety known as dolomite, as well as all intermediate types. Lime is simply calcined limestone, and in this general paper its uses have been included with those of raw limestone. It is of interest, in dealing with this subject, to glance back over the early history of the utilization of limestone, for by so doing we see that limestone has been of importance to mankind since the beginning of civilization and has contributed in no small measure to the development of a number of the arts and sciences. One of the first uses, if not the first use, of limestone was in connection with the making of lime for plastering purposes. This use antedates civilization. In the day of the ancient Greeks and Romans, the art of plastering had been brought to a state of perfection that is not nearly approached by the modern artisan.

Jan 1, 1930

By C. H. Buck, A. J. Taylor

"In 2015 Vale’s Clarabelle Mill began the process change to enable a higher degree of Cu separation. The flowsheet modification was part of a complete divisional flowsheet change being implemented in Vale’s Sudbury Operations. This paper will centre on some of the Operational Readiness (OR) work, culminating in the commissioning of the circuit in March 2017. The emphasis will be on the implementation of an integrated test plan to prepare for the process flow change through the mill.BackgroundClarabelle Mill (CBM) began making a saleable Cu concentrate in 2006 with the installation of the Cu separation circuit. Typical separation rate was 35-40% of Cu in feed reporting to Cu concentrate based on a target Ni concentrate Cu:Ni target of 0.7-0.8. The remainder of the recovered Cu (55-60%) reported to Ni concentrate and was smelted through the Copper Cliff Smelter.In 2013 a capital project, Surface Facility Upgrade (SFU), was implemented to focus on matching the surface plants capacities with the future mine plan to maximize revenues. This was to be achieved by redistributing the metal flow, specifically Cu, through CBM to increase metal unit content through the Smelter. The amount of redistribution of Cu was determined to be based on maintaining a stable Cu to Ni ratio (Cu:Ni) in the Ni concentrate.The change in Cu:Ni ratio in the Ni concentrate would affect the Sudbury divisional flowsheet, and required process changes across the all of the surface plants. The detail that surrounds the flowsheet changes as a whole will not be discussed, but the outcome of the decisions plays a large role in the operational readiness interactions between the mill, its suppliers and its downstream customers."

Jan 1, 2018

By J. A. Beesley

This paper reviews contemporary international law concerning the seabed, current developments in the United Nations on the seabed, and the main outstanding problems. It emphasizes the importance that the Canadian government attaches to this area.

Jan 1, 1969

By R. C. Hartviksen, B. H. Boyum

"The Sherman Mine, Temagami, Ontario, is an iron ore pellet operation rated at one million tons per year capacity. Mining is done from three open pits in two bands of Keewatin iron-formation intercalated in a 'greenstone belt' thought to be part of the Archean 'Abitibi Belt'. The bands of iron-formation are tabular and steeply dipping, averaging 75 degrees. The principal ore mineral is magnetite.Blast holes, 1214 inches in diameter, are drilled on 28-foot centers, each hole being sampled and assayed for both total iron and magnetic iron. Concentration tests are made in the laboratory to determine the anticipated concentrate grade. Two classes of ore are recognized -'liberating' or 'refractory'. Blending is done on iron con-.tent, degree of ease of liberation (i.e. grain size) and chunkiness. The latter is important, as primary milling is done in autogenous mills. Actual daily mill results are compared with predicted grade from blast holes, exploration diamond drill holes and pit inspection. Hourly mill samples are analyzed by the X-Ray Fluorescent Analyzer, with emphasis on silica grade. In 1969, the pellet grade was improved from 7 .01 per cent silica natural to 5.50 per cent silica natural."

Jan 1, 1970

By B. D. Sparks, I. E. Puddington, F. W. Meadus

The continuous separation of bitumen from Athabasca tar sands, with a high clay content, has been demonstrated. Recoveries of 95 per cent or higher have been obtained. Further processing of this product, to produce an accept-able type of crude oil, would require less heat than currently used in the hot-water process. Also, by comparison, substantial savings in equipment and operating costs are indicated.

Jan 1, 1971

By S. D. Logan

This presentation describes a lightweight automobile body structure concept developed at DaimlerChrysler to support a high fuel-efficiency vehicle project. This body structure consisted primarily of large thin-wall magnesium castings and resulted in a more than 40% weight reduction with a minimal cost increase over a conventional steel structure while achieving significantly improved structural performance as evaluated through CAE simulations. One concept vehicle was built for the purpose of demonstrating concept feasibility. Several slides showing the prototype build process are presented. The presentation also describes several large thin-wall die casting body applications that are in current production or have been used in recent production automotive applications and identifies areas where further development could improve the chances of a magnesium intensive body structure becoming a production reality at a later time.

Jan 1, 2006

By A. Fischersworring-Bunk

The new inline six spark-ignition engine is the realization of BMW's concept of efficient dynamics at high technological level to achieve the attributes of low weight and high efficiency, The paper presents different aspects of the development and manufacturing of BMW's inline six-cylinder engine magnesium-aluminium composite crankcase, Reference will be made on the AJ magnesium alloy optimization approach to balance between mechanical properties and the high pressure die cast ability requirements, Next to this aspect some mechanical design issues will be covered, with CAE methods playing an instrumental role in the early project stage for the assessment of the compound concept, Due to the compound design chosen, the interface posed challenges to both design and productions, A set of novel techniques has been used to cope with these tasks.

Jan 1, 2006

By S. Khoshkhooei

In this research, the effects of rare earth elements addition on thermal fatigue behaviors of AZ91 alloy were studied. Repeated heating and cooling cycles were applied on the samples at 170°C and 210 °C to develop thermal fatigue cracks, Crack growth mechanisms and microstructural influences were investigated by optical and scanning electron microscopy (SEM) as well as energy dispersive X-ray spectroscopy (EDS), Thermal fatigue behaviors were improved successively by addition of up to 2-wt% RE, This improvement is attributed to consummation of the aluminum of the melt by precipitation of the needle shape Al 11 RE3 phases, This process reduces the volume of Mg17Al12 phases and consequently decreases the brittle Mg/Mg17Al12 interfaces which are the main reason of weak thermal properties of the alloy at rather high temperatures, Further additions of RE, however, reduced the thermal shock resistance of samples by increasing in the mean length of the brittle needle shape phases.

Jan 1, 2005

By V. Gregoire

THE DEVELOPMENT by the Iron Ore Company of Canada of the Quebec-Labrador mining project, which eventually led to 'Iron Ore in 1954', involved, from the start, several distinct undertakings. Among them, the most important were: The construction of a 360-mile railway, linking Knob Lake with Seven Islands. The erection of a railway terminal, and harbour facilities, at Seven Islands itself. The building of an entire townsite at Schefferville (formerly Knob Lake) The construction of two hydroelectric plants; and, finally, The development of a sufficient number of orebodies to enable a production of 10 to 15 million tons of ore a year. Since these phases of the project have already been the subject of previous discussions, this paper will not elaborate further on them but will rather concern itself with a brief outline of the Company's current mining practices.

Jan 1, 1958

By M. M. Williams

WESTERN CAN ADA'S coal industry has experienced a serious set-back since 1949, following a pattern well known to its counterpart in the United States. The loss in coal markets in Western Canada has been particularly severe as the discovery of large reserves of oil and natural gas and the subsequent construction of re-fineries and pipelines roughly coincided with the dieselization of both main railways. While the coal industry will have to face a further decline in markets of long standing, others with a large growth potential can be se-cured if present marketing methods are changed where needed and if fundamental and applied research programmes are actively pursued. The energy and chemical potential of Western Canada's coals will eventually find their place in the ever-growing needs of industry and electric power producers. Electric power generation would appear to offer the largest and most immediate market for coal. If the coal industry is to serve this market adequately and gain as much of it as possible, coal operators ? must have a good knowledge of certain characteristics -of the electric utility industry and its fuel requirements. This paper is prepared primarily to set out some of these characteristics, but also discusses other probable markets for coal.

Jan 1, 1958