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This paper outlines the position and capabilities of Western Canada's bituminous coal industry, and indicates the increasing importance of Japan as an export market. The use of coal in Japan is reviewed, especially as regards future trends, and an appraisal is made of Canadian coal in comparison with domestic Japanese coal and imports from other countries. The importance of maintaining a solid nucleous within the Canadian bituminous coal industry is emphasized. I N RECENT years, Japan has emerged as a valuable market for Canadian exports. The first major product exported in volume to Japan was wheat, which has become very successfully established in Japanese markets. Following this, iron ore gradually found a market in Japan, with exports usually based on long-term contracts. This iron ore was produced entirely in British Columbia In 1958, the Western Canadian bituminous coal industry -jointly with the Dominion Coal Board -sent an official mission to Japan to investigate the

Jan 1, 1964

By J. W. Craig

CHROME ore, which is used in Canada in the production of ferro-alloys, in a variety of refractories, and indirectly in many chemical industries, is both commercially important and scientifically interesting. The sight of chromium metal is familiar to all of us in the home, the office, the automobile. Chromium is synonymous with armaments: it is understood to be one of several essential metals in tanks, which played an important role in the defeat of France in the spring of 1940. Chromium, in other forms, comes into our daily lives by way of paint and leather, of the familiar green ginger-ale and beer bottles, and more indirectly in every pound of steel produced in the .Dominion. Necessary to our civilization in peace and war, the ores of chromium occur in many corners of the earth. This paper attempts to describe the chemical constitution of chrome ores, their world distribution, and the various chrome products and their industrial applications in Canada.

Jan 1, 1940

By P. S. Arthur, G. R. F. Alvear

Development of a new smelting process is risky. Many novel processes in the metals industry failed to fulfil the initial expectations of their inventors. Large sums of capital have been invested in technologies that either didn't provide a satisfactory return on investment, or didn't perform at all, and had to be replaced. One of the keys to success in process development is incremental scale up of the technology, with potential problems being identified and rectified as early as possible. In this way the cost of any rectification that is required can be minimized. The ISASMELTTM process was developed to maturity by Mount Isa Mines through the 1980's and 1990's using incremental scale up. Commercialization only occurred once the process had been proven on laboratory, pilot and demonstration scale over many years. As a result ISASMELTTM technology now operates successfully at numerous plants around the world. The methodical approach to development of the technology has allowed owners to modernise their existing operations or create new businesses with significantly reduced technical risk.

Jan 1, 2011

By W. M. Armstrong

THE GROWTH of the major iron and steel industries on this continent and in many European countries was based on the use of as-mined, high-grade, lump iron ores and on the availability of metallurgical coking coals. The modern coke-fired blast furnace was developed for such materials and is one of the most efficient of ail pyrometallurgical processes. Most of the impure pig iron produced by blast furnaces was converted to refined steel by the Bessemer process in the years prior to 1900 but, when large quantities of low-cost steel scrap be-came available, the more flexible open hearth process was adopted by most large steel producers on this continent. Although this pro-cess has many desirable metallurgical features, the thermal efficiency is low, the capital cost is very high, and the method of charging scrap steel is inefficient by modern standards of material handling. In recent years several conditions have arisen which have stimulated the development of many new pro-cesses and the re-examination of the existing smelting and steelmaking techniques.

Jan 1, 1958

By Gaston Gendreau

CETTE PRÉSENTATION traitera des différentes phases des opérations de la mine du Mont-Wright depuis ses débuts jusqu'à présent. A une brève description de la géologie du gisement, suivra un exposé des méthodes d'exploitation de la mine et du genre d'équipement utilize.

Jan 1, 1977

By D. Mills, W. J. Brantina

"Mechanical and magnetic characteristics of ferromagnetic materials were investigated by a pulsed ultra-sonic technique. Two instruments, the Ultrasonic Attenuation Comparator (Sperry) and the standard type Reflectoscope (Sperry) were used for measurements of the attenuation of the ultrasonic pulse. The effects of elastic tensile and compressive stresses on the attenuation of annealed and cold worked material are described. In addition, the effects of plastic de-formation, relaxation and aging processes and different ultrasonic test frequencies are reported. The results for Armco iron, SAE 1020 steel, SAE 4340 steel and AISI 420 stainless steel are shown. Under the test conditions, the attenuation was found to be largely a sum of two components; a ""dislocation"" component associated with the losses accompanying the oscillations of dislocation line segments and a ""ferromagnetic"" component associated with the microeddy currents generated by magnetic domain wall oscillations. Either of these components might be dominant depending on the nature of the particular specimen and the test conditions. Finally, the possibilities of using ultrasonics in residual stress determinations, in fatigue studies and in the study of the ductile-brittle transition in ferrous materials, are briefly discussed."

Jan 1, 1960

"In developing a backfill system handling tailings feed to and from the storage silo, it is necessary to establish a slurry laboratory to develop the technology and silo design criteria. This paper presents the principles involved in such development and the importance of testing principles for optimizing the slurry system. Evaluation procedure based on experiments is applicable to a wide range of materials and allows silo design by scaling up the data gained from model tests. Silo simulation has been successful to design and operation, so becomes an effective approach to backfill applications. IntroductionThe silo is a device comprising specialized equipment and operating with related procedures for storing and handling the mill rejects as backfill slurry. It provides a steady supply of the solids slurry, prepared at desired pulp density under the continuous feed conditions. Because the silo system is designed to accomplish specific objectives when dealing with a particular mill tailings slurry, it is necessary to characterize certain slurry properties, behaviour of the solids slurry and understand the silo performance to establish design criteria. Bench-scale, pilot-scale and dewafull- scale experiments were employed in developing the load-storage-discharge system, and routine procedures are now available for pre-design testing. Silo model experiments and full-scale tests were conducted to define the design parameters and evaluate the silo performance. A silo can be designed by scaling up the silo model geometry and data obtained during tests.Since the early 1960s, silo backfill systems have been widely established. The shape and size of the silo and the operation procedure, as practised, all appear to be relevant to successful operation. Understanding the basic material properties and behaviour of solids slurry retained in the silo will help perfect the silo design, operation procedure and, consequently, improve the silo performance."

Jan 1, 1997

By D. Atkinson

"Porphyry molybdenum-tungsten mineralization on the east flank of Hudson Bay Mountain crops out over 5 km2 and is intersected to depths of 2 km. Features such as a hornblende-biotite aureole, mineralogical zoning and dike, vein and fracture geometries within lithologies of the Middle to Lower Jurassic Hazelton Group and Cretaceous Skeena Group reflect an intrusive complex, the Upper Cretaceous to Early Tertiary Hudson Bay Mountain stock which has been intersected by drill holes. The stock is believed to be the mineralizing agent. A southeast-dipping granodiorite sill has been outlined by drilling within the Hazelton Group. Molybdenite and scheelite veins cut all rock types; however, the granodiorite sill hosts a higher density of fine-grained, banded, quartz-molybdenite and pegmatitic quartz-molybdenite veins reflecting a competency contrast between the intrusive sill and other country rock. Due to the relative abundance of these veins, grade is higher within areas of the sill. Above the 15000£ cross-cut 20.6 million tonnes grading 0.401% MoS2 and 0.041% W03 have been defined. During exploration of the deposit sampling procedures had to be adjusted because of the nugget effect attributed to drill intersections of banded and pegmatitic veins.IntroductionMolybdenite was discovered in outcrop at the foot of Kathlyn Glacier on Hudson Bay Mountain and first reported by the Geological Survey of Canada in 1944. The deposit has several names: Hudson Bay Mountain or Glacier Gulch, both after its location, and Yorke-Hardy after the original staker.The deposit is on the east flank of Hudson Bay Mountain, 9 km northwest of Smithers, west-central British Columbia, within NTS area 93L/14 (54° 49' North, 127° 18' West, Fig. 1). Hudson Bay Mountain, on the southern edge of the Bulkley Valley, is a dominant topographical feature reaching 2590 m elevation. Mineralization is partly overlain by the Kathyln Glacier which is visible from Highway 16. Access to the 3100 m of underground development is from a portal at 1066 m elevation on the east slope of Hudson Bay Mountain."

Jan 1, 1995

By Jerry Ran

Many large underground mines using the open stoping method have changed their primary applications of consolidated rock fill (CRF) to paste or consolidated hydraulic fill due to considerations of demand in infrastructure and equipment, system reliability, backfill capacity and material sources. However, some smaller or even large mines still use or consider using CRF for backfill purpose due to factors such as capital expenditure, availability or suitability of other fill types or in some cases local regulatory requirements. As demands on CRF applications diminish among major mining companies, there is a lack of recent literature on application of CRF to open stoping in design and operation. There are several methods being used for fill strength design. Results from these methods have been successfully applied to paste or hydraulic fill. However, the design strength for CRF is much higher than that determined by use of these widely accepted methods. In operation, CRF preparation and placement have significant impacts on the quality of placed CRF and therefore the mining performance. This paper reviews the current fill design methods and their applications to open stoping with presentation of the bench marking data, presents fill failure cases and various CRF preparation and placement arrangements and discusses quality assurance and control programs.

Jun 1, 2012

By W. M. Armstrong, John A. H Lund

The paper describes an investigation of some of the tensile properties of single crystal vanadium, poly-crystalline vanadium and polycrystal-line tantalum, in the range of: W°C to -196°C. Techniques employed in the preparation and testing of specimens are discussed in detail. Some results of determinations of the temperature dependence of yield stress and ductility are given, and discussed in terms of the Cottrell-Bilby Theory of yielding. At subnormal temperatures, all the body-centred cubic transition metals in the Periodic Table exhibit; a) the "yield phenomenon" in tension, b) a strong temperature and strain rate dependence of yield stress, and c) a large decrease or complete loss of ductility. The yield phenomenon (existence of an upper and lower yield point) has been explained by Cottrell and Bilby ( 1) in terms of the dislocation-locking effect

Jan 1, 1961

By Yongjie Bu, Wei Sun, Zhiyong Gao, Yuehua Hu, Hongbiao Tao, Runqing Liu, Central South University

"The flotation behavior of O-isopropyl-N-ethyl thionocarbamate (IPETC) and pH for chalcopyrite and galena was studied through pure mineral test, adsorption quantity determination, solution chemistry calculation and Materials Studio simulation. The results show that the recovery differential value of chalcopyrite and galena is about 20% when pH of the pulp 9.5 and IPETC is 7×10-4 mol/L, the flotability differences of the two minerals is significant. There is competitive adsorption between OH? and IPETC on mineral surfaces, it lead to galena flotability is lower than chalcopyrite flotability. IPETC can remove the hydration layer on mineral surface and adsorb on active sites for collector adsorption, minerals have a better hydrophobicity.INTRODUCTIONCopper and lead are two of the most widely used metals in industrial and living, their applications include building construction, various metal alloys, heat and electricity, machine manufacturing (Zhang et al., 2014). Chalcopyrite and galena are the major source of copper and lead, normally they associated with each other. With the growing use of these resources, high grade and dissemination large particle sizes minerals are less and less, the use of low grade and complex dissemination minerals have to be paid more attention (Chen, Ye, & Li, 2010; Liu, Sun, Hu, & Wang, 2009). As the special properties and complex composition of copper-lead sulfide ore, flotation separation of chalcopyrite from galena effective is a research emphasis and difficulty point in mineral processing (Bruckard, Sparrow, & Woodcock, 2011).In the separation process of chalcopyrite and galena, it is rather important to choose effective collector (Huang, Wang, & Liu, 2014). Enlarging and using the two mineral flotability will be a good basis and start in flotation (Reyes-Bozo et al., 2014). Qin et al. (2013) made a great deal of research on flotation separation of copper/lead concentrate, collector O-isopropyl-N-ethyl thionocarbamate (IPETC), butyl xanthate (BX) and ammonium dibutyl dithiophosphate (ADTP) were investigated, BX and ADTP floated both chalcopyrite and galena well, specific adsorption appeared in the surface of mineral, the problem was the collectors were not selective enough, however IPETC showed better selective."

Jan 1, 2016

By W. H. Zieman

NORMAN WEISS, Milling Engineer, American Smelting• and Refining Company: The subject of the Forum on Rod and Ball Mill Liners is very fascinating, and there is no end of discussion when operators get together on grinding. However, the hypotheses and suppositions easily outrun the facts, especially when we •consider the inaccuracy of many reported observations. Still surprisingly small is the number of concentrators even reasonably well equipped to measure power consumption of each grinding mill, together with running time, so that data on this tangible factor, at least, can be obtained with precision. While the more elaborate devices of this nature, producing for each 24-hour period the total power consumption, average kilowatt hours per hour, short-term demand chart, instantaneous demand, and print-out, may cost in the neighbourhood of $2,500 per mill and may be difficult to justify, the combination of an ammeter, watthour meter, and running-time meter will cost only a few hundred dollars, so there appears to be little reason not to in-stall them in view of their numerous advantages.

Jan 1, 1959

High Pressure Grinding Rolls (HPGR) are said to be a good option in new grinding circuits. Due to their low energy consumption compared to other grinding systems such as SAG milling, there is a strong incentive to check their behaviour for certain ore types. With rising energy prices the operation will become even more beneficial in future. As published in the past, the HPGR is claimed to increase the liberation of the valuable mineral component within an ore. An investigation at the research centre of Polysius was conducted to substantiate the liberation behaviour in finish grinding operations. A pilot scale HPGR test unit (POLYCOM MAGRO) with a roll diameter of 950 mm and processing capacity of 80 t/h was used. Grinding tests were completed with a screen and a two stage drying air separation process (SEPOL). Analysis included standard screen analysis, fractional XRF and modern MLA technology. A technique was developed to oppose the amount of produced slimes (resuming bad flotation) against the positive effect of producing high mass fraction at flotation-easy sizes. The paper shows how effective the use of a dry grinding separation could be in terms of production of mass of liberated metal.

Jan 1, 2012

By Lisa L. Van Loon, Neil R. Banerjee

Canada is a world leader in uranium exploration, but many deposits are located in remote regions making exploration targeting challenging. Novel approaches are needed to detect the presence of large-scale ore-forming systems and to vector toward mineralization. Boron is commonly used as a key pathfinder element associated with sandstone/unconformity-hosted and basement-hosted uranium deposits in the Athabasca Basin, but the genetic relationship remains uncertain. Alteration assemblages containing boron geochemical anomalies are commonly spatially-associated with – and possibly coeval with – uranium mineralization. Boron is commonly found in tourmaline minerals but in some portions of ore deposits the host mineral for the anomalous boron remains cryptic. Boron coordination chemistry within alteration haloes can better constrain boron host mineralogy, provide insight into the nature of the boron-uranium relationship, and thus has the potential to better constrain targets for exploration. Synchrotron-source X-ray absorption near-edge structure (XANES) spectroscopy is a direct, element-specific analysis that identifies boron coordinated in both trigonally- (BO3) and tetrahedrally-coordinated (BO4) forms. This makes XANES uniquely suited for identifying the geochemical hosts for boron that may be related to hydrothermal ore forming processes. XANES spectroscopy was conducted on whole-rock assay powders from uranium deposits across the Athabasca basin containing boron concentrations ranging from <10 ppm to >10,000 ppm. XANES directly identifies the relative amount of trigonally- (BO3) and tetrahedrally-coordinated (BO4) boron in these complex mineralogical mixtures. Our work suggests a link between boron and uranium that is likely related to the unique physiochemical characteristics of ore bearing fluids that may provide a unique vector to mineralization.

Jan 1, 2020

By C. J. Coulson, G. A. McKay, A. M. Cormie

"The Leitch mine, in the Beardmore area, Thunder Bay district, Ontario, is a part of the Leitch estate. It includes a group of patented claims, staked by P. A. Leitch of Port Arthur early in the century, along bands of jasper, hematite, iron-bearing slates, carbonatized schists, and greywacke, commonly known as 'iron formation'. The folding and shearing in these variably interstratified beds is a striking structural feature. The vein pattern is very definitely related to these structures.ROCKSThe rocks in the area are typical Keewatin lavas-greenstone-overlain by a series of Timiskaming sediments consisting of arkosic greywacke, iron formation, slate, greywacke, conglomerate, and greywacke, in this order from the contact. The sedimentary beds are generally conformable with the older rock contact except on local folds.Small intrusions of diorite occur as nearly vertical dykes and are believed to be of Algoman age. To the northwest of the mine there are larger intrusions of granodiorite belonging to the same period.Several dykes of quartz diabase up to 100 feet in width, striking generally north and south, with a vertical dip, cross the property. These have been classified by W. C. Laird as pre-Keweenawan in age. One of these dykes in particular is of importance for it cuts through the No. 2 vein and serves as a pillar when stoping. It is approximately 6 feet wide.The youngest rock type represented is a sheet of olivine diabase that extends over an area of thousands of square miles in and around lake Nipigon. It underlies most of this area and its outcrops form some of the most interesting topographical features, with fault scarps rising hundreds of feet. In the vicinity of the mine shaft the sheet is about 600 feet thick and extends from a depth of 1,871 feet to approximately 2,470 feet. It has a dense, hard, chilled margin and a sharp, tight contact. It intruded the sediments with very little lateral disturbance. The chief effect was baking, which darkened and hardened the greywacke near the contact. The sheet dips flatly to the cast."

Jan 1, 1954

By R. L. Veenstra

This paper explores the connection between the stresses observed and the failure mechanisms present in the modelled cemented paste backfill. In order to look at this connection, the authors have used a previously developed model to conduct a sensitivity analysis of the model?s strength and permeability input parameters. The results from the sensitivity analysis were then compared to determine what causes modelled stresses and failure mechanisms to vary. Increased insight into the behaviour of the modelled paste will help clarify how paste behaves in the field.

Aug 1, 2013

By I. Spector

A SHORTAGE of cement in the Prairie Provinces, together with an aggressive policy on the part of the Saskatchewan Government in bringing new industries to the province, combined to create a favourable set of conditions for the establishment of Saskatchewan's first cement plant on the outskirts of Regina. Built by Saskatchewan Cement Corporation Limited, this single-kiln plant, tl1e latest addition to cement producers on the Prairies, began operations in the Fall of 1956. Location of the plant followed the trend of building cement manufacturing facilities in market areas rather than at raw material sources. In 1957, all assets of the Corporation were taken over by Inland Cement Company Limited and the plant and quarry now operate as Saskatchewan Cement Company, an Inland division. The Regina plant's production makes up approximately eleven per cent of the productive capacity of all plants in the Prairie Provinces. At present, two types of cement are manufactured -normal portland and sulphate resisting.

Jan 1, 1960

By J. N. Van der Merwe, M. Mathey

"We present an analysis of the mechanical properties of coal specimens from various coalfields and seams in South Africa. Our database comprises of 1800 test results from uniaxial and triaxial compression tests, as well as indirect tensile strength tests, which we collected from the various mining houses and research agencies in the country. We inspected the database for possible errors and present a brief description of the verification procedure in the paper.In the analysis, we reveal that the collected samples of strength and elastic properties of South African coals can be represented by single lognormal or normal distributions with only few outliers. This finding indicates that the samples realistically approximate the population of mechanical coal properties in the country and may suggest that the properties are randomly distributed. Significant coalfield- or seamspecific trends for the mechanical properties of coal are not clearly discernible from our data.Typical coefficients of variation for the individual mechanical properties range between 25-50 % on a country-wide and seam-specific level of analysis. Average uniaxial compressive strength values, however, are closely clustered for all seams. A comparison with data available from international coal strength studies show the distinct difference between South African coals and seams in countries of the Northern Hemisphere, where differences in the average coal seam strength are more pronounced.We observe that the number of specimens whose failure mode is influenced by the presence of natural discontinuities reduces drastically with the application of very small confining pressures to the specimens. Further, the strength-reducing influence of discontinuities diminishes with increasing confining pressures."

Jan 1, 2015

By James D. Bittner

Separation Technologies, LLC (ST) has developed a processing system based on triboelectric charging and electrostatic separation that provides the mineral processing industry a means to beneficiate fine materials with an entirely dry technology. The environmentally friendly process can eliminate wet processing and required drying of the final material. The process requires little if any pre-treatment of the material other than grinding and operates at high capacity ? up to 40 tonnes per hour by a compact machine. Energy consumption is low, approximately 1 kWh/tonne of material processed. Since the only potential emission of the process is dust, permitting is typically relatively easy. In contrast to the other available electrostatic separation processes that are typically limited to particles greater than 75 µm in size, the ST belt separator is ideally suited for separation of very fine (<1 µm) to moderately coarse (300 µm) materials with very high throughputs. The triboelectric particle charging is effective for a wide range of materials and only requires particle ? particle contact. The small gap, high electric field, counter current flow, vigorous particle-particle agitation and self-cleaning action of the belt on the electrodes are the critical features of the ST separator. The high efficiency multi-stage separation through charging / recharging and internal recycle results in far superior separations and is effective on fine materials that cannot be separated at all by the conventional electrostatic techniques. Since 1995, this triboelectric process has been extensively used for the beneficiation of coal fly ash with eighteen separators in place and over 130 machine-years of operation at locations in North America and Europe. ST has also installed separators for the beneficiation of industrial minerals in North America and Europe. The technology has been successfully applied to the beneficiation of a variety of minerals including calcium carbonates, talc, barite, and potash.

Aug 1, 2013

By S. Akhlaghi

In many electronic/optoelectronic devices, interaction between the metal stack and solder is undesirable. If a reaction happens, a nonuniform joint containing spikes and voids is likely to form and as a result the heat dissipation deteriorates significantly, which in turn, leads to the degradation of the bond. In the present work the interaction between Ti/Mo/ Au metallization system, which was sputter deposited on AlN substrates, and Pb-Sn solder was studied by using scanning electron microscopy (SEM). Also, an EDX system was used to trace the changes in chemical composition of the layers after solder tests. The microstructural examinations show that the Ti and Mo layer from the Ti/Mo/ Au metallization system are not impermeable enough and thus Ca from the surface of the substrate moves all the way up to the interface of Au/Mo and forms an intermetallic at the interface, which grows over time.

Jan 1, 2006