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By Leon J. Perrier

The paper describes the equipment in use, haulage grades, road conditions, tire sizes, tire performance and related problems. Various types of failures and causes, corrective action taken, tire records and reporting for control are also discussed.

Jan 1, 1977

By J. C. Heaslip

Introduction The greatest single advance in rock drilling practice since the advent of percussion drills was the introduction of tungsten carbide tipped rock drill?bits. The evolution of rock drills has been a long and highly diversified effort which has culminated in the highly refined ?drilling machines we know today, but because of the spectacular possibilities shown by ?detachable bits, and especially those with tungsten carbide inserts, there is little doubt that the cutting face of .the drilling unit has in recent days stolen the spotlight of rock drilling research and commanded the major attention of the rock drilling fraternity. "Solid" Steels Until about twenty years ago, all rock was drilled with a one-piece rod with a bit forged on one end. In the early years of the art of rock drilling, there was tried every conceivable pattern of :bit from the single-edge chisel to elaborate geometric 'designs. In the end, it was found that a 4-point bit with two sharpened cutting edges crossing each other at right angles would serve best for most rock drilling requirements. For some years thereafter, the main concern of drill manufacturers was .to obtain the best possible steel for drill rods. This was not accomplished as easily as might be thought. The cutting end had to be such that it could be hardened sufficiently to do its work without premature dulling and yet not so brittle as to shatter under the multiple impacts.

Jan 1, 1951

By L. M. Lowe, D. B. Chambers, D. G. Feasby

"The presence of the naturally occurring radioactive elements uranium and thorium in rare earth (RE) resources can present challenges in achieving regulatory and social acceptance. The discovery and awareness of radioactivity in mineral resources radioactivity typically generates strong public intuitive responses that may be project prohibitive; a significant proportion of such resources contain radioactivity.The objectives of this paper are to demystify the presence of uranium and thorium in RE resources and to demonstrate how a RE project can be safely developed, operated and closed from a radiological perspective. Radioactivity in RE resources is principally thorium-based. Thorium is interesting and challenging from a metallurgical perspective – one of those stubborn metals commonly assessed as refractory. Thorium is difficult to mobilise into solution and easily precipitates out. Thorium is a common element in the earth’s crust – about 10 ppm on average, and natural geophysical systems conclusively demonstrate its immobility. Specific mine tailings contain elevated levels of thorium, but the contained thorium is neither a significant ecological nor a personal hazard.Waste management for a hard rock rare earth project includes the management of mineral processtailings, waste rock, and metallurgical residue. Proven strategies are available for tailings and waste rockfor all climate conditions. The management of the metallurgical residues is potentially more challenging.Example robust strategies for addressing these challenges are presented.A potential way to reduce the radioactivity of rare earth metallurgical wastes is to selectively remove uranium and thorium. Uranium oxide is readily marketable, but its concentration as a byproduct typically triggers extensive regulatory processes. Thorium is presently not marketable, but may be so in the not-too-distant future with the development of thorium-based nuclear energy. The pro’s and con’s of uranium and thorium byproduct recovery are summarized."

Jan 1, 2016

By Luis R. Fonseca, C. Raimat, C. Wendeler, A. Sanz

"Rockfall barriers are widely known as proven efficiency element to protect infrastructure by catching the rock blocks in the falling direction and absorbing the energy generated by them.It’s common in the project design phase and during installation, fix rockfall barriers for catch a high percentage of the falling blocks and in many cases consider as valid the solution when the barrier can capture all of them. However, in many cases it’s possible to consider the use of these protections, simply to guarantee a secure shed for the traffic and intercept simply the blocks that theoretically hit the road surface.The results of the high-energy rockfall protection barriers type GBE which protect GC-200 road in Las Palmas de Gran Canaria are shown in this paper.The topographic data should be especially detailed observed and even more if you want to apply the technique of ""shadow zone"" with a flexible gallery system. It should be drawn from detailed topographic maps and drawings (photogrammetric restitution) to the scales 1/1000, 1/500, or 1/200; and it is important not to ignore the presence of vertical cuts, tracks, small slopes that modify the trajectories (trampoline effect, hard points that favor the rebounds) and which are not always presented in the drawings.The ""shadow zone"" is defined as the protected area, located at a lower elevation to the line created by the rockfall barrier to except of trajectories of rocks and free from the influence of the deflection of the system under the maximum energy level for which it was designed (MEL)."

Jan 1, 2015

By Brennan Lang

Why Seal Tunnels? ?Restore groundwater levels to pre-mining conditions. ?Saturate rock mass to reduce acid rock drainage. ?Reduce discharge flow to the environment. ?Reduce or regulate flows to a water treatment plant.

May 1, 2002

By W. A. Jones

"The Ross mine, a subsidiary operation of Hollinger Consolidated Gold Mines, Limited, is near the north end of lot 1, con. II, Hislop tp., Ontario. The property comprises the north half of lot 1, con. II, and the south onethird of lot 1, con. III. It is readily reached by a good motor road from the village of Ramore, 7 1/2 miles to the southeast on the Ontario Northland railway. The mine is being developed to a depth of 1,500 feet, and the current daily production rate is approximately 300 tons. From the inception of operations in March 1935 until December 31, 1945, 692,000 tons of ore, with a total value of $5,762,685, was milled . The silver to gold ratio of 1.48 to 1 is unusually high for Ontario gold mines.TYPE OF 0REBODIES AND MINERALIZATIONThe orebodies consist of lens-shaped and pipe-like stringer lodes and tabular vein zones composed of parallel quartz stringers. The host rocks are steeply inclined eruptive breccias and tuffs, striking N.70°W., intruded by very small stocks of red syenite. The orebodies appear to be spatially related to an intricate system of fault planes. Hydrothermal alteration is widespread and is not zonally related to individual quartz stringers. The wall-rocks contain abundant fine-grained pyrite, but gold is confined to the quartz stringers.RELATIONSHIP TO REGIONAL STRUCTURELack of outcrops has prevented the detailed mapping of the Keewatin complex in the vicinity of the Ross mine with the degree of success that has been achieved in the Porcupine area.A northwesterly trending belt of slates and greywackes, bounded by faults, forms the central part of a broad anticlinal arch about 3 1/2 miles north of the Ross shaft. Lava flows forming the south flank of the structure face south toward the mine. If the sediments are to be tentatively correlated with the large areas of Keewatin slates and greywackes of the Porcupine area, it must be assumed that they are younger than the lava flows and that they have been down-faulted."

Jan 1, 1954

By DON E. MacDONALD

Marl in Alberta is confined to highly specific geological, hydrogeologica/ and climatic settings. Tufa is fa irly abundant in those areas of western Alberta where bedrock is of the Paskapoo Formation. Marl and tufa originate when the following conditions are met: presence of a carbonate source in drift or nearsurface bedrock; leaching of the carbonate by percolating groundwater; transportation of calcium and bicarbonate ions in a permeable aquifer; discharge at the surface as springs, seeps or lakes; re-precipitation of calcium carbonate. Alberta has seven categories of marl and tufa deposits, based upon over-all depositional environment and calcium carbonate

Jan 1, 1984

By Frank E. Lathe

During the war the National Research Council at Ottawa sent out questionnaires to the managers of nearly all the industrial plants in Canada. Inquiry was made as to the research equipment possessed, the number of research workers employed and the nature of the research problems which still remained unsolved. Practically all the companies reported that they had no special facilities for research, had no re-search workers and did not require the assistance of the National Research Council-because they had no research problems. Perhaps we have here one of the chief reasons why certain of our manufacturers find themselves unable to meet foreign competition. For hundreds of years the Indian tribes of northern Chile worked, in a small way, the copper deposits at Chuquicamata. They had no research problems and made no striking success of their mining operations. Then came an American company with a research problem, which they proceeded to solve. To-day the stock of that company has a market value of about $140,000,000.

Jan 1, 1926

By G. E. Wittur

"The twenty-one members of the Organization for Economic Cooperation and Development, comprising eighteen western European nations plus Canada, the United States and Japan. account for two-thirds of world steel production. The Special Committee for Iron and Steel was formed by the OECD to study trends and problems in the steel industries of member countries. The paper begins with a summary on the Organization, including an historical sketch, its structure, member-ship and objectives. The steel industry of the entire OECD is briefly described before proceeding to a more detailed discussion of various aspects of the steel industries of European OECD members, emphasizing practices and conditions that differ from those in North America. Benefits to Canada of representation at meetings of the OECD Special Committee for Iron and Steel are described."

Jan 1, 1967

By Gerald Sanders

Presentation Topics ? We?re Going to the Moon Again? ? What is Lunar Mining ? In-Situ Resource Utilization? ? What Are The Challenges to Lunar Mining? ? What is NASA Currently Doing?

May 1, 2009

By J. Güntner

A significant portion of Outotec's business relates to the application of fluidized bed for processing a wide range of industrial materials, including gold ore and gold concentrate. As part of the former Lurgi and Boliden organization, our division constructed the first industrial reactor for roasting sulphur-bearing materials in 1950, based on the principles of fluidized bed technology. This process, when combined with efficient heat recovery and off-gas treatment and its conversion to sulphuric acid, became the standard for processing sulphur-bearing ores. In the last 60 years we have delivered more than 265 plants and developed (in addition to the standard fluidized bed solution) variants of the fluidization technology, such as the circulating fluidized bed and the bubbling fluidized bed. This paper describes the different options of the fluidized bed technology for gold roasting reflecting on main process design criteria.

Jan 1, 2011

By W. Schubert, N. Radoncic

"The term “squeezing” is frequently used, although it is ill defined. Definitions like “large and long lasting displacements” raise the questions about the threshold values for the magnitude and duration of displacements. Large displacements during tunnelling frequently are observed in fault zones with high overburden. Whether this causes problems very much depends on the design approach used. On the one hand, the magnitude of expected displacements has to be predicted prior to excavation to provide for enough allowance for the displacements without violating the clearance profile. On the other hand, the support characteristics must be compatible with the expected imposed strains. As the magnitude of the displacements and thus the strains in the support depend on the support capacity and its characteristic (yielding potential), only well engineered systems will be successful.Experience in Alpine tunnels over the last decades has shown that closed shotcrete linings can sustain a strain of approximately 0.8% to 1% without failure. Any strain above this value inevitably leads to failure of the lining, and thus a loss of resistance, causing additional displacements. Based on a large number of simulations, a criterion for a critical overburden depth up to which closed linings can be used has been developed. Traditionally open gaps in the shotcrete linings have been used to allow for larger strains. To enhance the efficiency of the linings, yielding elements have been developed, which are integrated in the shotcrete lining, allowing large strains and controlled development of support resistance (Figure 2). When designing such yielding support systems, the development of the displacements, as well as the rheological behaviour of the supports must be considered. As the development of displacements to a large extent depends on the face advance, also the advance rate has to be considered, to be able to compare the time-dependent strength of the lining to the stresses developing as a result of the imposed strains. Another issue is the compatibility of the rock bolts with the large strains. With standard grouted bolts, there is a potential that the “fresh” grout is sheared due to the initially large strain rates. Special rib designs of the bolts allow for a higher strain tolerance.For successful tunnelling through fault zones quality monitoring and up-to-date data evaluation is of crucial importance. With advanced evaluation tools, changes in the ground conditions ahead of the face can be reliably predicted. With the help of empirical relations, the development of the displacements for different advance rates and supports can be predicted, allowing for the determination of the required overexcavation.The paper presents a review of the development of ductile elements, methods of analysis, and monitoring data interpretation."

Jan 1, 2015

By C. Edwards

ABSTRACT The versatility and specificity of rare earth elements (REEs) have led to their use in an everincreasing variety of applications in new technologies; consequently, demand for REEs has increased significantly. However, separating REEs safely and effectively is a complex and expensive process. This paper presents a review of REE mineral processing technologies, providing an update on current capabilities in REE mineral processing and REE extraction from the major commercially valuable REEbearing minerals such as bastnaesite, monazite, and xenotime, as well as the ion-absorption type of REE deposits.

Jan 1, 2013

By L. I. Kiss, A. Larouche, V. Dassylva-Raymond

Control of the quenching capacity of the cooling water is of primary importance for maintaining the quality and recovery rate of ingots produced by direct chill casting. Industrially, this can be done using a cylindrical metallic probe undergoing rapid quenching by direct immersion in a reservoir filled with casting water. Such a test rig originally developed at Alcan Arvida Research and development Centre was modified and used to assess the role of key parameters affecting the boiling heat transfer. During the tests, the probe of the instrument undergoes the effects of different heat transfer mechanisms. An experimental study was performed in order to clarify the details of the probe-water heat transfer during rapid quenching. The heat flux along the surface was determined by mathematical modeling using the measured temperature signals, while the corresponding heat transfer regimes like stable and unstable film boiling, nucleate boiling and natural convection were identified by the analysis of high-speed video recordings. Aluminium

Jan 1, 2006

By L. H. Cole

Introduction The increasing importance of the gypsum industry in Canada is evidenced by the fact that the production has increased from 473,129 tons valued at $809,632 in 1909 to 1,205,846 tons valued at $3,622,007 in 1928, an increase of over 155 percent in quantity, and of 347 percent in value, in the 20-year period. Although the export trade in crude gypsum still forms a large proportion of the industry, it is gratifying to see that the home consumption is steadily increasing, and while the percentage of the crude gypsum mined that is manufactured into the calcined products in the country is only 16.8 per cent, its value is practically 50 per cent of the total gypsum production of the whole country. It is to be hoped that each succeeding year will see an increase in the amount manufactured in Canada, and, with the steady growth of the country and a serious endeavour to capture a part at least of the world market in gypsum products, the outlook for the industry is decidedly promising. The value of gypsum as a commercial commodity has been known from the time of the early Egyptians; in fact its value for certain purposes has been known so long chat the date of the discovery of its peculiar properties is unrecorded.

Jan 1, 1930

By J. R. Dinn

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

Jan 1, 1934

By S. Fahland, P. Vogel

"The Gorleben salt dome has been investigated since 1979 for its suitability as a repository for the disposal of high-level radioactive wastes. The geoscientific surface exploration was followed by underground exploration of the site beginning in 1983: underground excavation work included the sinking of two shafts from 1986 to 1994, the excavation of the infrastructure area and of drifts located in the first exploration area EB1 within the following years. The exploration was interrupted for ten years from 2000 to 2010 as part of a moratorium. After the expiry of the moratorium in March 2010, the geoscientific underground exploration at the Gorleben site was resumed. The investigations were interrupted again in autumn 2012 due to a political decision. The exploration programme included extensive geoscientific investigations: geological exploration, geophysical investigations, mining exploration and mining observation, laboratory tests, in-situ geotechnical measurements, geological modelling and numerical model calculations. To analyse and interpret the results of the in-situ measurements and mining observation geomechanical, thermal and thermo-mechanical model calculations were carried out. One of the main elements of the in-situ geotechnical investigations were high-resolution geothermal measurements performed in boreholes used for geological exploration and geotechnical tests.The geothermal measurements are used to evaluate several geotechnical findings, e. g. drift closure, rock deformation, stress change, and are completed by thermal model calculations to analyse and interpret the results of in-situ measurements and mining observation. The model calculations have been carried out using the special purpose JIFE code. To consider the whole exploration mine with the adjoining host rock as well as the successive excavation of drifts and boreholes in detail a three-dimensional finite-element model was developed. The model calculations are used to analyse the cooling-off of the surrounding rock of the drifts caused by ventilation. The cooling-off of the surrounding rock is an ongoing process affecting the results of further geotechnical measurements in the near field of the drifts. To predict a realistic time and space dependent distribution of the temperature field of the host rock within the exploration area which is influenced by ventilation thermal model calculations are necessary. Comparing the calculated temperature field with the in-situ determined rock mass temperature field within the exploration area EB 1 the results show a sufficient agreement. Furthermore there is very good correspondence, both qualitatively and quantitatively, between the experimental and the calculated findings regarding the temperature profiles including the effects of excavation and ventilation of the drifts."

Jan 1, 2015

By H. W. Manley

SULPHUR, like the minerals of coal, iron and petroleum, is one of the essential materials in our modern expanding industrial civilization. Before discussing the salient features of the production of sulphur from the Canadian sour gas, it seems appropriate to outline the historical past and probable future utilization of sulphur. The ancient Greek writer Homer spoke of its "pest-averting sulphur" and the "divine purifying fumigation". Ancient alchemists found sulphur to be a fascinating and baffling material. The discovery of gun powder in the year of 1250, and its application to the art of war a, century later, made sulphur an important commodity in the progress of mankind. The initial manufacture of sulphuric acid in the year of 1736 by the Englishman Joshua Ward, established the basis of a chemical industry that today utilizes 80 per cent of the consumption of elemental sulphur. Commercial production of the chemical soda ash ( N a2C03) discovered in 1787 by the famous Leblanc Process, in-creased international demand for the element sulphur and marks the birthday of the Sicilian sulphur industry.

Jan 1, 1961

By R. D. Browns

In his Budget Speech on March 31, 1 977, the Honourable Donald S. Macdonald expressed concern about the financing of investments through new equity issues. He mentioned the need to render more attractive participation in the equity market by investors in all in come brackets. One of the measures introduced in the budget to accomplish this goal is the proposal to increase the dividend gross-up and tax credit in respect of most dividends received by an individual from Canadian companies. The following comments and tables serve to illustrate the impact of this particular proposal.

Jan 1, 1977

By F. Hassani, E. Aflaki, M. Nokken, M. Kermani

"This paper presents and compares the physical properties of Gelfill and cemented hydraulic fill (CHF) obtained by lab experiments. Gelfill consists of tailings, different binders such as Portland cement, fly ash and blast furnace slag and an alkali activator such as sodium silicate. The CHF and Gelfill samples with various mixture designs were cast and cured for 28 days. The influence of sodium silicate concentration, pulp density and mixing time on the mechanical properties of samples were evaluated using the uniaxial strength test. Mercury intrusion porosimetery (MIP) was used to analyse the microstructure of CHF and Gelfill samples.This study concludes that: (i) The mechanical properties of CHF can be improved by the addition of appropriate amount of sodium silicate. (ii) The rate of strength acquisition in Gelfill samples is faster than CHF samples over 28 days of curing period. (iii) Mixing time strongly influences the mechanical properties of Gelfill samples but did not have any effect on CHF samples. (iv) The MIP analyses indicate that the pore size distribution and total porosity of Gelfill and CHF were different, and this did contribute to higher strength development of the Gelfill samples. INTRODUCTIONThe increased depths of mines in the Canadian Shield and the high stress associated with these depths favour a new method of mine backfill that can both meet strength requirements and help mine productivity. The mine backfill mainly consists of tailings, water and binder materials, the latter being most expensive. Gelfill is a new mine backfill material whose binder usually consists of alkali activators such as sodium silicate and other cementitious materials such as blast furnace slag and normal Portland cement. Although sodium silicate has been used in concrete manufacture, the use of this material in mine backfill is relatively new (Doucet, 2007, Razavi, 2007). Until very recently there have been only a few isolated publications, mostly out of McGill University, regarding mine Gelfill (Razavi, 2007 and Kermani et al., 2009 and 2010). These papers have investigated some of the basic mechanical properties and mechanical behaviour of Gelfill. However, the physical performance of Gelfill in various conditions has yet to be understood. Therefore, the main objective of this study was to investigate the influence of mixing time and sodium silicate concentration on the mechanical performance of Gelfill and CHF through a series of experiments. Moreover, the microstructure of the Gelfill and CHF samples was studied."

Jan 1, 2015