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By H. G. Rushton, A. S. Romaniuk

"The opening chapter of this volume, by A. Ignatieff, places in perspective Canada's coal resource base as part of the world scene. This chapter will focus on the Canadian scene.Units of measurement in this report are in the International System of Units (SI) as approved for official use by the Canadian Standards Association and Metric Commission Canada. These units have been adopted by the Mining Association of Canada and the Coal Association of Canada. To assist with the shift to metric units these two associations have published ""Metric Practice Guide for the Canadian Mining and Metallurgical Industries"", 1978(1J, Appendix ""A"" lists some useful conversion factors along with SI prefixes. The last official assessment of Canada's coal resources and reserves was done by the Department of Energy, Mines and Resources and presented in Report ER 79-9 ""Coal Resources and Reserves of Canada"", published in December 1979 and authored by H.U. Bielenstein, L.P. Chrismas, B.A. Latour and T.E. Tibbetts(2). The Geological Survey of Canada has a continuing project concerned with coal resource assessment as does CANMET, whose concern is with coal reserve assessment and coal quality. As well, Alberta's Energy Resources Conservation Board (ERCB) has a continuing assessment program for coal in Alberta and publishes an annual reserves report, the current issue of which is cited as reference No. (3). The difference in resource and reserve terminology as used by EMR and ERCB has a major effect on derived tonnages for Alberta. This difference will be discussed later. In 1982 the Department of Energy, Mines and Resources produced a map titled ""Canada-Coal""<4J which outlines coalfields and illustrates coal import and export movements for the years 1981and1980. A copy of this map is contained in the map pocket of this publication. Two other resource assessment reports are noteworthy, the first is ""Coal Resources of Southern Saskatchewan: A Model for Evaluation Methodology"", by J.A. Irvine, S.H. Whitaker and P.L. Broughton<SJ which is one of the major outputs of a joint federal-government study of southern Saskatchewan's lignite deposits. (Another output from this same study' is the Geological Survey of Canada's SASCO file, a computer processable file holding borehole and coal quality data.) The second is ""Deep Coal Resources of the Interior Plains, Estimated from Petroleum Borehole Data"", by G.D. Williams and M.C. Murphy(6) which identifies coal resources from nearly 4,000 petroleum exploration boreholes distributed uniformly over an area spanning Manitoba, Saskatchewan, Alberta and British Columbia."

Jan 1, 1985

By Ela Mielczarski, Jerzy A. Mielczarski

"The adsorption of xanthate takes place at a different potential on each major sulfide mineral, hence, as it was demonstrated in the past, each mineral component can be selectively separated from ore under well controlled potential conditions. In real flotation this concept never works out for two reasons: the potential of single mineral particle results from complex surface reactions controlled by solution chemistry, and there is a galvanic interaction between different mineral particles present in the flotation pulp.In this study the formation of amyl xanthate hydrophobic products on pyrite, galena and chalcopyrite has been spectroscopically investigated in the presence of combinations of these minerals. The type of the adsorbed species and their amount were determined directly on mineral surfaces by infrared external reflection technique. Galvanic contact between grains of two different minerals has tremendous consequence on the adsorption of collector on both minerals. The detected changes are dramatic, from no adsorption to a coverage formation of a few monolayers. The results obtained indicate clearly that the observations and conclusions about the collector adsorption, hence also the surface hydrophobization, made for a single mineral system does not describe the real situation in a multi-component mineral system such as flotation pulp."

Jan 1, 2003

By Juan E. Rassmuss

Durante mucho tiempo la explotación del azufre en el interior del Perú, ha sido de manera regular dado su bajo consumo nacional y cotización en el mercado peruano. Asi, solo ciertos yacimientos ubicados en el norte de nuestro país producen y generan divisas que no sobrepasan los 6 millones de soles. En el marco de esta situación, el objetivo del siguiente estudio, pretende reactivar el consumo nacional de los yacimientos del Sur del país, -en tanto volumen e importancia comercial por medio del uso de un método de beneficio apropiado. La formación de los yacimientos del Sur, a diferencia de los de Piura y Bayovar, se da por la emanación postvolcánica de gases sulfurosos, generandoimpregnaciones de azufre en las lavas y tufos del Terciario Superior y Cuaternario. Posteriormente se produjeron fracturas en las zonas contíguas de los volcanes, formando depósitos lenticulares de extensión variable. Dichos depósitos son superficiales puesto que solo cerca de este espacio se puede mantener la oxidación del sulfuro de hidrógeno y los gases están a temperatura baja para depositar azufre. En cuanto al costo del azufre tenemos el costo de explotación, beneficio, transporte y embarque. Finalmente, se deduce que la fundición del azufre como la filtración, soliflucción pueden ser favorables en el uso de métodos de explotación menos costosos, asi como el incremento de la explotación depende de un mercado común estable y de un cálculo exacto de los costos de producción.

Jul 20, 1956

By Meherwan C. Irani

The Bureau of Mines is developing a new technological approach to handling the problems of fires in abandoned coal mines and waste banks. This new technology involves the accelerated combustion of "waste" coals in place (i.e., in situ) under controlled exhaust ventilation conditions, which allows for total management of the combustion products; including utilization of the heat produced" This new concept could significantly lower the costs of reducing the environmental and public safety hazards associated with waste coal fires, and could lead to the conversion of a coal waste to a coal resource. The controlled burnout technology has progressed from the laboratory stage to a full-scale field evaluation stage at the site of an abandoned-coal-mine fire. This first report describes the site selection, evaluation, and preparation, and the design and construction of the full-scale controlled burnout installation. Subsequent reports will deal with the results of the operational field trial.

Jan 1, 1983

By Y. Paul Chugh

NIOSH and the Illinois Clean Coal Institute are funding studies on characterization of coal and quartz dust in Interior Basin mines since 2009. Coal dust characteristics vary significantly and, are vital for the development of the engineering controls. This paper presents wettability characteristics of coal dust with respect to its chemical and physical properties, since wettability is considered to be a primary dust control technique. Particle size distribution, inter-particle interactions during wetting and quartz associations with organic and inorganic matter in coal seams is critical for understanding wetting phenomena. Silica content in the un-wetted fractions was found to be very high during wetting tests. Wetting of quartz may be limited by its association to hydrophobic materials as well as buoyancy forces resulting from particle size characteristics and particle-particle interaction in the wetting agent. Temperature of the wetting solution and effective contact time between dust particles and water droplets are found to be two important variables affecting the wettability. The characterization data obtained from this study can be utilized to develop engineering controls.

Jan 1, 2011

By C. Dinis da Gama

Because of the growing importance of back analysis for the interpretation of rock slope failures, particularly in open pit mines, it is suggested a methodologic sequence of activities for dealing with those problems. The principal mathematical tools for the interpretation of the most common mechanisms of slope failures are reviewed, including methods of stress and strain analysis, which seem to be more powerful for parametrization studies, and for developing more realistic explanations of slope behaviour, such as the measurement of displacements. An application of those methods is described, using slope failures detected in a Brazilian uranium mine (Cercado), thus providing reliable shearing strength parameters for the rock mass discontinuites, which were used in the final pit design. The concept of using backanalysis results to supply input data for pit design was implemented by means of the excavation of an experimental trench within mine limits, where specific instruments were installed, and several slope failures were monitored and backanalysed, in order to yield information about sliding mechanisms in the future open pit.

Jan 1, 1983

By C. Hennesmann, D. Maijer, S. L. Cockcroft, P. Yo

"Die cast aluminum wheels are one of the most difficult automotive castings to produce because of stringent cast surface and internal quality requirements. As part of a collaborative research agreement between researchers at the University of British Columbia and Canadian Auto Parts Toyota Incorporated, work has been underway to predict heat transport and porosity formation in die cast A356 wheels. The basic heat transfer equations have been solved using the commercial finite element package ABAQUS to which specialized routines have been added to predict porosity. Preliminary work on predicting porosity formation focused on using the Niyama parameter as a measure of the probability of porosity. The latest version of the model incorporates a new fundamentally based porosity criterion, which takes into account the effect of hydrogen concentration. The development of this model together with its application to a series of cylindrical test castings as well as a production cast wheel are presented.I. IntroductionDie cast aluminum wheels are one of the most difficult automotive castings to produce because of stringent cast surface and internal quality requirements. Microporosity, in particular, is a common defect that can adversely affect wheel quality. The mechanism of microporosity formation in aluminum alloys is complex owing to its dependence on the interaction of a number of phenomena occurring during solidification including the decrease in hydrogen solubility, the decrease in volume, the development of the solidification structure, and the increase in difficulty in interdendritic feeding [1]. As a result, the amount, size, and distribution of microporosity is affected by a large number of casting parameters including thermal variables, melt composition, grain structure, modification, and inclusion content, making optimization by trial-and-error methodologies difficult.The use of criteria functions, based on thermal conditions during casting, offers a relatively simple approach to predicting microporosity. In practical terms, they are useful because they provide a straightforward method of assessing the impact of varying casting parameters on porosity through various thermal parametersl21 such as thermal gradient, cooling rate, solidification time, and solidus velocity. Drawbacks of criteria functions include insensitivity to varying hydrogen concentration and the limitation to qualitative predictions. Consequently, in aluminum alloys, attempts have been made to develop models incorporating the effects of hydrogen gas and microstructure evolution. However, these types of models represent a significant increase in complexity and sacrifice the simplicity and ease of application of the thermally based criteria functions."

Jan 1, 2001

This publication is designed to be helpful in promoting health and safety in tunneling and related operations. The format has been selected and arranged to provide a condensed guide for safety personnel, inspection and investigative agencies, design and project engineers, and others responsible for the health and safety of workmen. All the precautionary measures recommended are based on actual conditions observed, from investigations of fatal or serious accidents, and from research conducted to find ways and means of alleviating hazards and unhealthful conditions. Many of the recommended rules are included in State laws and in the general safety requirements of the construction industry. Explanatory, descriptive, and qualifying information has been largely omitted in this publication to keep basic data in more useful and compact form. Included in the appendixes are special precautions for gassy (methane atmospheres) tunnels and tunnels where petroleum products are encountered.

Jan 1, 1968

By D. J. Hutchinson, M. Lato, M. Diederichs

Light Detection and Ranging (LiDAR)-based applications for geomechanical purposes have recently proven to be a highly reliable and accurate form of remote analysis and documentation. The ability to remotely collect, process and evaluate rockmasses for structural geomechanical applications has benefits ranging from safety to efficiency, and provides a permanent record that can be assessed before and after an excavation has been completed. With the collaboration of Queen’s University and Rio Tinto, the Iron Ore Company of Canada (IOC) mines in Labrador City, Newfoundland and Labrador, evaluated the practical application of the I-Site 4400 LiDAR equipment, in conjunction with the Vulcan geotechnical module for geomechanical purposes. The project provided a comparative analysis between conventional hand-mapping and digital analysis. The analysis indicates that digital mapping could be employed as an active tool within the general geotechnical workflow, where results would be used in pit wall and rockmass support designs. As well, the field work enabled the generation of effective operational guidelines and protocols to maximize scanning efficiency.

Jan 1, 2009

By D. Yamada, T. Tanaka, N. Inouchi, J. Nakahigashi, H. Yoshimura, T. Nonishi

The use of cereal food materials as lubricants was investigated in an attempt to develop nonpolluting lubricants. Suspensions of wheat flour in water and other types of cereal food lubricants were prepared and their friction coefficients measured. The results indicate that a cereal food lubricant containing 30% lipids, 2% proteins, 60% carbohydrates and 0.6% calcium carbonates has the lowest friction coefficient for a sheet (cpTi-1). As example applications, the lubricant was tested with a forming press and a screw-fastening device. In both applications the cereal food lubricant performed relatively well in comparison to conventional lubricants and thereby has potential for practical applications.

Jan 1, 2006

By L. Yuan, A. Smith

In order to provide insights for the optimization of ventilation systems for U. S. underground coal mines facing both methane control and spontaneous combustion issues, a computational fluid dynamics (CFD) study was conducted to model the potential for spontaneous heating in longwall gob areas. A two longwall panel district using a bleeder ventilation system was simulated. The permeability and porosity profiles for the longwall gob were generated from a geotechnical model and were used as inputs for the CFD modeling. In this study the effect of methane emissions from the mined coal seam, including the longwall face and overlying rider seam reservoirs on the gob gas distribution was considered. The spontaneous heating is modeled as the low-temperature oxidation of coal in the gob using kinetic data obtained from previous laboratory-scale spontaneous combustion studies. Unsteady state simulations were conducted and the effects of the coal’s apparent activation energy and reaction surface area on the spontaneous heating process were also examined. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.

Jan 1, 2007

Previous published papers by Fraser (1), Hey (2), and Stillwell (3), have given respectively, details of:-1. The practice in the pilot plant operated at Zeehan for the treatment of ores from the Rosebery field.2. The design, based largely on the experience gained at Zeehan, of the concentrator built at Rosebery.3. The nature of the orebodies of the zinc-lead lode at Rosebery.Changes and developments, at the Rosebery concentrator, since operations commenced, are now described with particular reference to recent practice.Three concentrates are produced, viz.: a copper, a lead, and a zinc concentrate. The current flow-sheet is shown in Fig. 1. Typical concentrate assays are...THE OREThe ore treated is derived from the Rosebery and Hercules Mines and is, milled in the ratio of, approximately, two parts of the former to one of the latter. The ores from the two mines may be considered as being similar in general character, although the Rosebery ore contains more pyrite. It is from this mine that any increased tonnage is expected. The ore is a mass of fine-grained, intimately associated sulphides, with practically no coarse...

Jan 1, 1949

By Mark I. Copeland

The Bureau of Mines investigated the effect of up to 1 wt-pct of copper and silicon on the heat treatment response and hardness, tensile, and impact properties of hot-rolled medium-carbon steels. The steels were prepared by induction melting and fabricated into plates by forging and rolling. The tensile strength of 0.2-wt-pct carbon steels containing 0.3 wt-pct silicon was affected significantly by copper in both the hot-rolled and heat-treated (600° C) conditions, whereas the tensile strength of the 0.3-wt-pct carbon steels was less affected. A 600° C treatment was considered optimum as a post-rolling treatment to strengthen the steels by copper precipitation. Strengthening of 0.2-wt-pct carbon steels by silicon was reduced by increasing copper contents.. Optimum impact strengths occurred at about 0.3 wt-pct silicon in 0.2-wt-pct carbon steels containing 0.6 and 0.8 wt-pct copper. The impact strengths were lowest for 0.2-wt-pct carbon steels containing over 0.8 wt-pct copper and greater than 0.3 wt-pct silicon, especially in the heat-treated condition. Copper and silicon solutes and copper precipitates strengthened the steels. This effect was augmented slightly by strengthening through grain refinement by these solutes.

Jan 1, 1973

By E. R. Spencer, E. Reeves

National Institute for Occupational Safety and Health (NIOSH) researchers conducted an investigation to quantify sound levels and to determine the amount of sound reduction provided by engineering noise controls installed in a talc processing plant. Baseline sound level and sound intensity measurements were performed at the plant and the measurement locations were recorded for comparison to post-control measurements. Follow-up measurements were then made at the same locations after the initial noise controls were installed. The plant subsequently decided to implement additional noise controls and the researchers returned to conduct measurements for a final analysis of all noise controls. The most significant results showed a sound level reduction in the main mill area from a range of 93-104 dB(A) down to 90-94 dB(A), and a total sound power level reduction of 21 dB(A) for air classifying mill 3.

By S. Onuki, T. Ando, M. Tejima, R. Enomoto, Y. Okada

"Al–Si–Cu–Mg die casting alloys are widely used in the automotive industry, and recent advancements in high pressure die casting technology enable heat treating products to achieve desirable properties. However, CO2emissions associated with die-casting production lines should be reduced to address the global warming issue. In this study, the relation between the microstructures and thermal stability of precipitates formed during isothermal aging at 423, 485, and 558 K of Al-11.0 mass%Si-1.8 mass%Cu-0.2 mass% Mg (JIS ADC12) was investigated using Vickers hardness tests and transmission electron microscopy (TEM). The hardness tests and TEM results showed that Si compounds and Al–Cu compounds enhanced the mechanical properties of the alloy and that the predominant compound affecting the mechanical properties differed between specimens treated at 423 K and those treated at 558 K. Moreover, additional aging at 423–458 K resulted in a material with a Vickers hardness higher than that of the isothermally single-aged material. Differential scanning calorimetry, differential elemental analysis, and selected-area diffraction analysis using TEM suggested that the combination of Al–Cu compounds precipitated at low aging temperatures and Si compounds precipitated during preliminary aging increased the mechanical strength, resulting in a maximum hardness of 130 HV.INTRODUCTIONAl–Si–Cu–Mg die casting alloys have well-balanced mechanical properties, machinability, and cast ability. These alloys are therefore widely used in the automotive industry because of their superior characteristics, accounting for>90% of the aluminum used in die casting production. As a substitute for iron-based materials, these alloys have contributed to the development of lightweight vehicles.Dong et al. (2014) reported that the heat treatment of die casting materials is effective for changing their dimensions under high temperatures as a result of the precipitation of solid-solution elements. Recent advancements in high pressure die casting technology have led to the application of heat treatments of Al–Si–Cu–Mg alloy products to reduce fuel consumption and satisfy customer needs. Although attempts to reduce CO2emissions have focused on fuel consumption in cars and fuel efficiency regulations have become increasingly strict in recent years, CO2discharged from production lines should also be reduced without adversely affecting the properties of the product. Heat treatments for artificial aging after solution treatment (T6 treatment) and after casting (T5 treatment) are CO2discharge sources, which together with a holding furnace account for >80 % of the CO2discharged during the casting process."

Jan 1, 2018

By O. A. Ojo, R. G. Ding, M. C. Chaturvedi

In this study, the fusion zone microstructure of tungsten inert gas weld of a directionally solidified NhAl-base alloy was examined by the standard metallographic techniques involving the use of optical, analytical scanning and transmission electron microscopes equipped with energy dispersive spectrometer. Fusion zone cracking was observed to be closely associated with interdendritic secondary solidification microconstituents identified as consisting of y, y&apos; and NiMo (Y) phases. Depression of solidification temperature to the terminal ternary eutectic reaction temperature of the system during cooling is suggested as an important factor contributing to the fusion zone cracking.

Jan 1, 2006

By Christopher Davey, Professor Emeritus, Marian Mazurkiewicz, Peter Kanjorski

The concept of a high pressure liquid jet mill with highly unsteady flow, has been developed and recently patented by Cornerstone Technologies LLC (CsT), for the purpose of micron and sub-micron particle production. The mill accepts feed sizes up to 15mm for some materials and is capable of sub-micron production. Successful material range from precious metals such as silver and palladium to dielectric components and substrates such as Barium Titanate slips, zirconia, titania and silica. The process has also succeeded in adequately reducing the size of materials for both composite and coating uses such as anthracite coal, graphite, chrome metal, wollastonite and more than 100 others. A unique design approach has been taken to highly maximize the energy flux in the mill’s chambers to create extremely high turbulence and destructive cavitation. This is assisted by shock waves, which cause particles to undergo ultra high frequency pressure pulsations, high frequency collisions and then abrasion, shattering, hydro-wedging, and cleaving. Due to these extreme properties the processing occurs in just fractions of a second allowing throughputs up to 1000 kg/h on a machine that would fit inside a 60 cm box. The technical solution and technological advance, as well as the environmental and economic benefits indicate rapid and wide spread acceptance of high-pressure liquid jet milling in modern industry.

Jan 1, 2003

Recent literature is reviewed with emphasis on the design and scale up of mixers. Most important aspects of mixing have resulted from the study of Newtonian fluids and only a minor attempt has been made to extend the work to non-Newtonian materials.The rheology of non-Newtonian materials is outlined and the typical behaviour of mineral slurries is indicated.The importance of flow velocity, flow pattern, and fluid turbulence is discussed with relation to suspension of solids and rate of reaction.Data on experimental leaching of ore from Mary Kathleen, Queensland, show the effect of different mixing impellers.In conclusion, factors involved in the selection of a mixer are presented with emphasis on economic appraisal after pilot experimentation.INTRODUCTIONThe subject of mixing has attracted considerable attention during recent years, but relatively little work has been undertaken for the study of non-Newtonian materials. Most work has been restricted to Newtonian fluids because there are less inconsistencies in such study.Mixing, by definition, implies blending or combining, and ranges from gentle mixing which blends the contents of a large tank in 24 hours to violent mixing which completely homogenises the contents of a tank within seconds. Metzner and Otto (1957) have pointed out the present lack of knowledge on the degree (or quality) of mixing. Apart from this fact the design of mixers for Newtonian materials would seem to be reasonably certain.Both capital and operating costs rise rapidly with increasing mixer size. Therefore the design, or selection, of a mixer is a matter for economic consideration in the overall aspect of plant design and operation.

Jan 1, 1961

By E. E. Harton

Bureau of Mines Information Circular 16, Bibliography of Investment and Operating Costs for Chemical and Petroleum Plants, was published in October 1949 as an aid in making estimates of investment and operating costs of processes for manufacturing synthetic liquid fuels. Development of such processes by the Bureau of Mines was authorized by Public Law 290, 78th Congress. This bibliography included refer¬ences to and abstracts of publications appearing from 1930 to September 1948 on all processes in general use in the petroleum refining and chemical industries. Publications in this field have been numerous since compilation of the above bibliography, and the present report was prepared to cover the field from September 1948 through June 1952.3/

Jan 1, 1955

By HOWARND N. EAVENSON

THE year 1930 resembled the preceding one in the coal industry in continuing the era of falling prices and &apos;of the abandonment of unprofitable mines. Practically all coal prices fell, and in the steam sizes during the last half of the year this was particularly true, due to the small industrial demand. No new mines of any size were opened in the bituminous coal industry, but there was a steady increase in the number of cleaning plants of all kinds built in all fields. It is estimated that at least nine million tons per year were added to the previous total of washed coal. The largest washing plant started during the year was that of the Buckeye Coal Co., at Nemacolin, Pa., with a capacity of 650 tons per hour. Fig. 1 shows - the mixing-bin, conveyor galleries, washing-plant and skip hoist, and Fig. 2 the 120-ft. Dorr thickener for collecting the 48-mesh material from the wash water. Dryers are used for drying the steam coal product. The following statement by J. R. Campbell shows the effect of cleaning on Pittsburgh coal in Greene County: "With the advent of the 650-t.p.h. efficient washing plant in Greene County at the Nemacolin mine of the Buckeye Coal Co., it has undoubtedly been demonstrated that the potential coking-metallurgical coals of the county can be brought within the pale of the highest grade high-volatile coals for steel manufacture. A few months&apos; operation indicates that 9% per cent ash in the raw coal can be easily reduced to under 7 per cent ash in the washed coal and the sulfur from 1.60 per cent in the run of mine to 1.20 per cent sulfur in the washed coal.

Jan 1, 1931