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By J. Tuzo Wilson

Abstract A division of part of the Canadian Shield into provinces believed to represent former mountain belts is attempted, special emphasis- being laid upon radioactive age determinations, the relation of Archaean to Proterozoic rocks, and the structure of the Grenville province. Original data on the distribution of radioactivity within several batholiths and their connection with ore deposits are' presented. The possible growth of continents and a theory which explains the shape and distribution of the world's younger mountain and island areas are discussed and applied to the Canadian Shield in an attempt to explain how the growth and present structure came about. The relation of the major mining camps of northeastern Ontario to fault zones is discussed in the light of this theory. Introduction The valuable symposium issued by this Institute to celebrate its jubilees emphasizes the important role of major faults in determining the location of many ore deposits in the Canadian Shield. Many of these faults are known to extend for long distances. It is therefore widely appreciated that it would be of great value if the pattern, ages, and causes of these faults were better understood. This would be particularly useful if the relations of the major fault systems to petrological and metallogenic provinces and to former mountain belts could be established. Each year the volume of available data, and hence the chance of reaching a fuller solution of this problem, increases. This article is a review of the present situation. It is accordingly based almost wholly upon the work and ideas of others, which are gratefully acknowledged. Naturally, responsibility for the selection and marshalling of the data is the writer's.

Jan 1, 1949

By F. M. Clement

British Columbia, unlike the Prairie Provinces, cannot lay claim to vast prairies. She can, however, claim many valleys, uplands and plateaus that are capable of marked agricultural development. It has been said that British Columbia is not an agricultural province. This may or may not be true, but at the present time agricultural production in this province stands second only to that of forestry. The industry has advanced from a total production of 8 millions in 1908 to a total production of 60 millions in 1924, a total increase of approximately 650 per cent in 16 years. In the last 10 years production has increased from 30 millions to 60 millions. No other industry can point to such a rapid development. In 1908 British Columbia imported 12 million dollars worth of foods compared to the 8 millions which were produced at home. In 1924 she imported 20 million dollars worth of foods compared to the 60 millions worth produced at home. In addition we exported foods to the value of approximately 10 million dollars. British Columbia is therefore self-sufficing in-so-far as values ar.e concerned except for approximately 10 millions of dollars. It is not to be expected that this province will ever grow all the coarse grains that she may require: these, along with certain meats, will always be a heavy item in the imports. We are concerned at the present time more with the value of the products than with the quantities produced: in other words, with quantities only in-so-far as ? quantities improve value.

Jan 1, 1925

By A. R. Sorta, D. C. Sego

ABSTRACT Temperature, solute, texture, and thixotropic effects on time domain reflectometry (TDR) measurements of water content in oil sands tailings are investigated. Results indicate that TDR water content measurements are influenced by temperature, residual bitumen, and percent clay in the tailings. A correction of 0.03–0.10/ °C must be applied to the apparent dielectric constant (Ka) to account for the effect of temperature. The Ka-volumetric water content relationships of slurries differ significantly from the commonly used Topp calibration equation. The age of the tailings and the addition of phosphogypsum did not influence TDR water content measurements.

Jan 1, 2013

By David Rahal, Des Erasmus, Ken Major

"Over the past twenty years there has been an increased emphasis on fine grinding in the minerals industry. This spurred the development of a range of new fine grinding equipment in the 1990s. At that time, the Knelson-Deswik mill was developed in South Africa for the pigments industry.Knelson Milling Solutions currently offers a wide range of laboratory, pilot and production scale mills. These mills bridge the gap between traditional low speed vertical mills and the high speed horizontal mills (tip speed < 3 and > 15 m/s respectively). They are designed to run at tip speeds between 10 and 12 m/s and are capable of operating with very dense grinding media. The result is a power intensity that is higher than the low speed mills and overlaps that of the high speed mills. This allows the mill to be customized for a wide range of grinding applications.A case study at Aquarius Platinum’s Kroondal Mine shows that the Knelson-Deswik technology can produce a consistent product size despite feed variations. It also shows that the throughput was proportional to the slurry density at Kroondal. The case study identified increasing the slurry density as a process change that can increase throughput and reduce the specific energy consumption.INTRODUCTIONThe increasing complexity and finer grain sizes of modern ore bodies have increased the importance of effective mineral liberation in obtaining acceptable grades and recoveries (Jankovic, Valery and La Rosa, 2003; Lichter and Davey, 2006; Napier-Munn, Morell, Morrison and Kojovic, 1996). This trend has increased the significance of fine grinding technology because the input energy increases exponentially as the required product size decreases from 100 to 10 microns (Gao and Weller, 1993a).The US Department of Energy recently provided the context for the potential energy savings in the US Mining Industry (BCS, 2007). They reported that grinding consumes approximately 494 TBtu/year. This was over double the consumption of the second highest equipment category, diesel materials handling systems (211 TBtu/yr). The proportion of grinding energy allocated to fine grinding can only be expected to increase as finer ore deposits are mined. It is therefore critical that fine grinding efficiency continue to improve through the selection of appropriate equipment and the development of best practices for existing applications."

Jan 1, 2011

By S. W. Stogran

"Chemical and limited biological monitoring of mine and mill effluents are being used by regulatory agencies to monitor and control discharges to the environment. Amendments to the Federal Fisheries Act may make it mandatory for mines to conduct Environmental Effects Monitoring (EEM) which will change the emphasis from monitoring effluents to monitoring impacts on receiving waters. The EEM amendments may expand the scope of present environmental studies to include: effluent mixing zone delineation; inventory and classification of resource, habitat, and historical receiving environment; effluent quality determination; chronic and acute bioassay testing; tissue analysis; benthic invertebrate monitoring; fish population surveying; fish tainting evaluation; and the evaluation of impacts on fish habitat, invertebrate communities and fisheries resources. The requirements for EEM have not yet been worked out by the mining industry and the government committee. Experience at Lakefield Research in conducting biological monitoring studies for the mining industry has shown that biological monitoring may be useful for assessing environmental impacts only if programs are planned and executed to collect relevant data, thus minimizing costs and maximizing effectiveness.IntroductionThe chemical monitoring of effluents and water bodies receiving effluents is common practice in the Canadian mining industry and has been used routinely by regulatory agencies to control discharges to the environment. Biological monitoring has also been used on a limited basis, primarily to augment chemical data collected. A number of regulatory bodies, primarily in Canada and the United States, have been incorporating biological monitoring into environmental regulations.Various forms of biological monitoring techniques have been used in Canada and the United States to help assess the impact of mining operations and effluents on the environment. Biological monitoring includes a wide range of activities, from monitoring metal uptake in individual organisms to examining the population dynamics in ecosystems. The most commonly employed biological monitoring techniques are the chronic lethality toxicity tests. Also becoming widely used are in situ and chronic toxicity tests."

Jan 1, 1994

By K. Harris, J. B. Wahl

Ni-base superalloy cast materials provide an outstanding balance of high temperature strength, fatigue resistance, oxidation resistance and coating performance and can be produced to very tight tolerances in extremely complex configurations, such as axial and centrifugal integral cast turbine wheels. As a result, cast superalloys are used in the most demanding applications of aero and industrial gas turbine engines. Use of these materials is expanding to smaller microturbine, turbojet, turbocharger and missile engine applications due to this unique combination of desirable properties. This paper will present an overview of the application of investment cast Ni-base superalloys and process capability to small turbine and missile engines.

Jan 1, 2010

By B. M. Currell, M. J. Neate, P. W. Bowden

Historically the hydrogen fluoride laden fume emitted from the electrolytic cells in the aluminium reduction process is further treated in pulse jet dust collectors. These dust collectors act as dry scrubbers performing two duties: adsorbing the gaseous fluoride emitted from the cells onto alumina dust; and collecting the alumina dust minimising particulate and fluoride emissions to the environment.Patented StarBag (TM) technology has been used in aluminium smelters in Australia as a means of increasing the dust collection and fluoride scrubbing capacity of existing collectors. This technology provides an alternative to major capital equipment upgrade where increased capacity is required, and potentially lowers the production cost per tonne of aluminium where capacity limitations are being realised and production expansion is required. This paper presents the findings of on-site pilot scale, and full production scale comparative tests, highlighting the operational and variable differences observed utilising the Star-Bag(TM) technology at Boyne Smelters Ltd in Australia. The results illustrate how this technology can be utilised to increase the hydrogen fluoride scrubbing efficiency and dust collection capacity of existing capital equipment.

Jan 1, 2006

The primary steel industry of the Prairie Provinces consists essentially of three companies whose total annual melting capacity, as of January 1, 1963, was 333,000 net tons. These companies have steel rolling facilities. In addition, there are five other companies producing steel castings by melting scrap in electric furnaces which, with the plants having rolling facilities, gives a total annual furnace melting capacity of 380,000 tons. Since 1954, the annual production of steel ingots and castings has ranged from a low of 66,588 tons, in 1954, to a high of 211,138 tons in 1961. The present facilities on the Prairies for making steel ingots from scrap, and rolling them to produce light merchant mill products, appear to be sufficient for many years ahead. Steel scrap, as electric furnace feed to make steel ingots for the present line of products, will probably continue to be available at reasonable prices either on the Prairies or from the north-central United States. It is recognized, however, that residual elements in scrap may be-come of greater significance and necessitate more rigid control of scrap quality.

Jan 1, 1963

By S. Esfahani, M. Barati, Y. Kauwachi

"Heat recovery from slag has gained attention due to its high potential in lowering energy intensity of metal extraction processes. A direct method to recover the thermal energy of slag is to use countercurrent air flow that extracts the heat from falling droplets. Often, the solidified slag is aimed to be used as a substitute for Portland cement, thus high cooling rates are required to form an amorphous slag with sufficiently strong hydaulicity. Rapid cooling however involves using large gas flow rates that in turn lower the thermal efficiency of the process. This article presents a mathematical model that was developed to determine the optimum conditions in the heat recovery process and to investigate the effect of the air flow and granule diameter on the cooling rate of the droplets as well as the thermal efficiency of the heat recovery system. INTRODUCTIONMetallurgical slags are the largest by-product of high temperature materials refining and extraction processes. The total amount of metallurgical slag produced in the year 2008 has been estimated at up to 422 million tonnes containing up to 222 TWh/y (Barati and Esfahani, 2011) of thermal energy. Over the past four decades attempts have been made to recover this substantial amount of energy as heat, electricity, or fuel, while none of the proposed method has been commercialized yet.During slow cooling the slag tends to crystallize the constituents (CaO, SiO2, Al2O3, etc.) into a hard, heavy solid. In the past, over 90% (Bengt, 1983) of the molten waste was discharged onto heaps and allowed to cool slowly, then crushed and used in road construction or land filling or as coarse aggregate for concrete. However, later it was found if cooled rapidly, the slag can be used as a substitute for Portland cement. As a result, processes such as wet granulation were created in which molten slag is fragmented with water, forming amorphous (glassy) phases. Despite its effectiveness in producing a suitable material, heat would not be recovered through this process. Thus, dry granulation was introduced in 1930’s and was developed further in 1970 – 1980’s."

Jan 1, 2012

By R. E. Gilmore

PREAMBLE THIS PAPER comprises material presented in two separate &apos;Papers at the British Commonwealth Scientific Specialist Conference on Fuel Research held in London, England, in July, 1950. These papers are now available for publication in Canada, since only essential parts of the conference discussions, in addition to the resolutions resulting therefrom, will be published in the official Proceedings of the Conference. Inasmuch as the information presented concerns Canadian organizations and training facilities for fuel research, it should be of general interest to Canadian scientists, and especially to the Coal Division of the Canadian Institute of Mining and Metallurgy. Part I, the alternate title of which is Facilities in Canada for Fuel Research and for Exchange of Information and Staff, does not include research on peat, oil shale, petroleum oils in general, and natural gas, and omits studies of the geology, constitution, and production of coal. Special reference is, however, made to research on the heavy crude oils and bitumen of the Western Prairie Provinces, and particularly to their production and treatment to produce crudes for oil refinery processing.

Jan 1, 1951

By P. P. Andrieux

The recovery of the Zone G crown pillar, located between the bottom of the open pit and the top of the underground workings at the Raglan Katinniq Mine in Nunavik, started in the summer of 2008 and should be completed by the end of 2009. This article describes the rock mechanics-based approach implemented to design the recovery of this valuable block of ore. The stereophotography-based ShapeMetriX3D technique was first used to provide a comprehensive assessment of the various joint sets that comprised the pillar. Then, the statistical distributions obtained for the dip, dip direction, spacing and persistence of these sets were used in conjunction with the geometry of the large-scale faults present in the area to build and run a series of explicit rigid numerical models. Each of these models had a slightly different jointing geometry, randomly constructed from these statistical distributions. Incorporating in a properly formulated numerical model the variability of some of the input parameters has allowed the engineering team to assess in a rational and reliable manner the likelihood of success of the proposed mining method and sequence.

May 1, 2009

By Martin Froehling, Curtis Mohns, Rahim Rajwani, Michael Fullam

"The Kemess mining and milling complex is operated by Northgate Minerals Corporation and is located in the mountains of north-central British Columbia, 430 kilometers northwest of Prince George. The complex consists of the Kemess South open pit mine and a 52,000 tonnes per day mill. Hypogene, supergene and leach cap ores are processed using conventional crushing, grinding, and flotation techniques to produce gold-copper concentrates with minor by-product silver value.The rougher flotation concentrate is re-ground in closed circuit before being cleaned to final concentrate grade. Historically, gold losses in the cleaner tailings were primarily associated with pyrite, with only minor amounts of free gold. More recently, with the processing of high pyrite ores, the major losses were found to be free gold less than 10 microns in size. The fine grind required for the high pyrite ores resulted in over-grinding of the free gold particles in the regrind circuit, contributing to poor flotation characteristics. It was thought that if this free gold could be recovered by gravity at coarser size in the regrind circulating load, the free gold losses in the cleaner tailings could be reduced.Preliminary test work carried out by Knelson Gravity Solutions indicated the potential for free gold recovery in the regrind circuit. A Knelson XD-30 Concentrator was installed with variable speed capability, and a series of optimization tests were carried out. In addition, cleaner tailings were characterized with gravity operating and with gravity not operating to determine the overall gold recovery benefit. The single Knelson XD-30 installation recovers ~10% of the total gold in the regrind circuit and increases overall recovery by 3% when high pyrite ores are processed."

Jan 1, 2007

By A. D. Misener

Introduction Temperature gradients have been determined for numerous locations in the Canadian Shield in connection with mining operations (1, 2, 12, 13, 14, 15). As part of a programme of geophysical studies of this region, some of these gradients were re-determined by the writer at locations where other thermal properties, specific heat, thermal conductivity, radioactivity, etc., were also to be measured. The ultimate object was to determine the heat flow to the surface at these locations. It was felt that the practice of determining heat flow from the temperatures and conductivities obtained in a single vertical bore hole (3, 4, 5, 6, 7, 8, 9) might give results which were appreciably divergent from the average for a considerable area. Particularly, it was thought that temperature gradients, whether obtained in a single vertical hole or from a number of random locations at various depths in a mine, might be subject to local variations and anomalies serious enough to render unsure any discussions based on them. The procedure followed in this investigation was to select a location where mine workings extended to considerable depth over a reasonably wide area. At selected depths below surface, horizontal drill holes extending into regions of undisturbed rock were located and resistance thermometers were inserted into these holes far enough to record the true rock temperature. An attempt was made to obtain a sufficient number of readings at or near any one level to give a representative coverage of the area selected. This ideal could not always be attained, but the large number of readings obtained for each are a does give a reasonably representative picture of the temperature conditions. These readings required much rime and movement of men and equipment underground . They could not have been obtained without the wholehearted co-operation of the management and considerable assistance from the personnel of the mines concerned.

Jan 1, 1949

By D. Weston

"IntroductionIn preserving this paper, the author would like to acknowledge the basic development work carried out by the Consolidated Mining & Smelting Company of Canada, without whose initiative the development of the Aerofoll mill would not have been possible. In particular, he would like to pay tribute to the late Mr. C. T. Oughtred, Superintendent of Concentration for Cominco, whose vision and research-mindedness was the chief contributing factor in the carrying alo.ng of the original development.He would like also to acknowledge the help and co-operation of the staff of the Mines Branch, Department of Mines and Technical Surveys, Ottawa, without which the finalization of the un.it and its application would have been many additional years in coming to industry; and the assistance and encouragement given so freely by Mr. C. W. Dowsett, Consulting Metallurgical Engineer, Ventures Limited, and Professor A. M. Gaudin, Massachusetts Institute of Technology."

Jan 1, 1950

By A. W. JR. Whitaker

Introduction Within the last quarter of a century the Lake St. John-Saguenay valley has been converted from a quiet agricultural district to one of the important industrial centres in the Dominion. First there was the expansion -of the pulp and paper industry, and then, starting a little over ten years, ago, the development, in large .blocks, of the enormous hydro-electric power resources of the Saguenay river. Coincident with this power development, the world aluminum industry was rapidly expanding and looking for a new source of cheap power. This was found in the Saguenay valley-and so, in 1925, Arvida was established by the Aluminum Company of Canada as a location for one of the largest aluminum plants in the world. Arvida, an incorporated city comprising an area of some ten square miles, is ideally located on a more or less level plateau about 350 feet above the Saguenay river. Seldom has industry stepped boldly forth and carved out of Nature a community with full city status. The process usually goes through the steps of camp, village, town, and city, involving improper planning or lack of planning; all of which has been avoided at Arvida by starting out in the right way. While this community has only a population of approximately 2,000 at the present time, it is carefully planned for a population many times this figure. Streets, city parks, business and residential sections, have been definitely planned, and, with a City government, proper ordinances were passed at the beginning to ensure the building and maintenance of a model industrial community. As the crow flies, Arvida is about 35 miles due east of lake St. John, and 0 miles west of the St. Lawrence river at Tadoussac. From a shipping standpoint, it is well served by the Canadian National railways, with direct lines to Quebec and Montreal, and by ocean shipping facilities at Port Alfred, which is about 15 miles to the east on the Saguenay river and is served by the Roberval & Saguenay railway. The latter has interchange connections with the Canadian National at Arivda, and also operates a branch line into the city of Chicoutimi.

Jan 1, 1933

By Charles "Chick" Rodgers

"The Key Lake uranium mine is the largest single uranium producer in the world. It is owned 2/3 by Cameco Corporation and 1/3 by Uranerz Exploration and Mining. Cameco is the operator. Current production is fourteen million pounds per year of uranium oxide (U308).The mine's location is 570 kilometres north of Saskatoon on the southern edge of the Athabasca Basin approximately at latitude 57° 11 'north and longitude 105° 34' west. Access to the mine is by an all-weather road and a private airstrip.The mill was commissioned in 1983. A molybdenum plant was constructed in 1989 in response to increasing molybdenum content in the yellowcake or final product. Early test work had showed that the first ore body to be mined, the Gaertner deposit, would present few problems with regards to molybdenum in the product. However, the test work also showed that the higher molybdenum content of the Deilmann ore, the second Key Lake orebody to be mined, would result in increased molybdenum concentrations. Without the molybdenum plant, penalties would become excessive and some product might not accepted by the refineries.This paper will describe the current Key Lake mill process with emphasis on the molybdenum solvent extraction process. It will cover the chemistry of the process, process development in the mid 1980's, and current operating practices.The Key Lake milling process consists of five individual plants, crushing and grinding, leaching -counter current decantation (CCD), solvent extraction, yellowcake/crystallization and bulk neutralization (Figure 1. Simplified Mill Flowsheet). A detailed mill flowsheet can be found in the appendix."

Jan 1, 1996

By A Falter

Gyroscopic surveying instruments, which apply the physical law of a gyroscope, are being used for deter-mining the azimuth of lines with a high degree of ac-curacy. In the past ten years, gyro-theodolites have been introduced widely for underground orientation in the mining industry of Russia, Germany and South Africa. Gyroscorpic methods eliminate awkward procedures of conventional shaft plumbing, and provide more safety, excellent control and the highest precision at any point under-ground without interference with hoisting operations. The advantages of gyroscopic orientation in geodetic surveys become obvious in primary and secondary triangulation, in the determination of co-ordinates of single triangulation points, using the method of trigonometric re-section and intersection, and when traversing over long distances or in areas with obstructed view. Other fields of application are found in geophysical surveys and in the orientation of technical objects; e.g. radar stations, relay stations and ballistic missiles.

Jan 1, 1964

By C. Matthews, A. Vo

"Australia is one of the world’s leading exporters of bulk commodities and the extensive use of sampling equipment is key to the successful management of each mining operation. At the process plant, without a full understanding of the feed, product and tails, it is impossible to fully optimise the performance of the plant, such that the metallurgical balance is often open to error. At the port, a statistically correct, bias free and compliant sampling system is crucial to ensuring exported minerals are reflective of their true value and to avoid penalties. Over the last decade, as a result of the iron ore boom, there has been high demand for reliable, representative and standard compliant solids sample systems in Australia. This paper reviews several solids sampling applications at Australian mine sites, the challenges and experience gained and how the implementation of reliable representative sampling systems has provided better understanding of plant process performance, improved plant control and overall benefits to the operations.INTRODUCTION Mining is the primary contributor to the Australian economy with Australia ranking in the top 4 in economic resources for 21 primary industrial minerals in 2016 (Britt, et al., 2017). Australia is one of the world leaders in the export of the majority of its commodities including gold, copper and iron ore (Britt, et al., 2017). Therefore, a suitable and standard compliant sampling system is essential for evaluating plant performance and content verification. At the mine and at the port, the larger iron ore miners in Australia have developed stockpile models to predict the grade of their ore down to individual blocks of the stockpile. This allows the miner to create the right blend of material for sale to their customers and ensures they are not underselling their product or at risk of penalties for impurities or low grade. As an example, the average difference between the benchmark 62% Fe and low grade 58% Fe fines at the time of this report averaged US $30/tonne according to the Metal Bulletin Iron Ore Index. At a shipload of 180kt this would be a variation of US $5.4M. Whilst this is an extreme example, it highlights the economic importance of producing the correct grade product and a recognised representative sample of said product."

Jan 1, 2019

By S. Xu

Magnesium alloy AM50 is of interest to automotive cradle application because of it excellent castability and good ductility. In this work, microstructure and mechanical properties of both low pressure die cast (LPDC) and high pressure die cast (HPDC) AM50 test bars are characterized. Microstructure was examined using optical microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM). Phase identifications were performed using energy dispersive x-ray spectrometer (EDS) and TEM diffraction. It has been found that LPDC produces much coarser microstructure than HPDC. At the same time, the HPDC samples are more heterogeneous in microstructure and composition close to grain boundaries. Particles with various dimensions and morphologies of two different intermetallic phases, Mg17A112 and A18Mn5, were found in all the samples. Mechanical tests were performed under conditions similar to those related to an engine cradle application. LPDC samples show lower strength but better creep resistance than HPDC mainly due to the difference in grain sizes and grain boundary microstructure between LPDC and HPDC. Creep curves are well described by the empirical Andrade equation. Tensile-compressive yield and creep asymmetries were found in AM50, i.e. better deformation resistance in tension than in compression. The average yield asymmetry ratio for all the samples is 0.87. Microstructural examinations on the samples tested in tension, compression and creep showed that the deformation mechanisms in AM50 were slip plus twining at temperatures up to 125°C. The examinations indicate the important role of twining in the asymmetry phenomenon. The creep results indicate that dynamic precipitation of the Mg17A112 phase during testing is not the mechanism directly responsible for the creep asymmetry in AM50.

Jan 1, 2004

By T. E. W. Nind

"A short description of the chamber lift method for producing oil wells is followed by some comments on compressor requirements and gas utilization. A quantitative analysis of the process is presented and, based on this analysis, criteria are suggested for selecting wells for which this type of lift might be suitable. The analysis leads to the conclusions that chamber lift is an efficient producing mechanism for wells having very low productivity indices (say about 0.05 bbl/d/ p.s.i. or less), but that for such wells optimum utilization of injection gas cannot be attained. It is suggested that the gas injection time per cycle should be kept as low as possible, compatible with a small oil fallback volume, and that the cycle frequency should be in the range of 20-40 cycles/ day. For wells with productivity indices of 0.2 bbl/d/p.s.i. or higher, chamber lift is relatively inefficient; how-ever, if well allowables are low it may offer an attractive, low cost, alternative to gas lift or pumping."

Jan 1, 1960