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By D. A. Wheeler, Rémi Tremblay

"INTRODUCTIONDuring the last few years, through Column Flotation Company of Canada ltd, the Centre de Recherches minérales has worked on the column flotation of coal, phosphate, feldspar, talc, graphite, copper, lead-zinc and diamond ores. The operating companies and prospective deposits were located in Canada and in other countries. Since these projects were financed by the concerned mining companies, all results remain confidential unless we obtain permission to publish. Three companies have graciously allowed us to use their information which I will describe in this text. These are the Polkowice copper mine in Poland, the North Coast Industries ltd graphite deposit and a talc company which preferred to remain anonymous. I will also describe our 2 inch column which was used for all tests. Data is also given on how to scale-up the 2 inch column to industrial size.Figure 1 presents a schematic of a flotation column. Feed, at a controlled rate and pulp density, enters at about 1/4 of the height of the column from the top. A controlled rate of air is bubbled into the bottom of column through a fine-holed sparger. The column volume between the feed point and the top of the sparger is called the recovery zone. Tailings, at a controlled rate, always slightly greater than the feed rate, discharges from the bottom of the column. This difference in feed and tailings flowrates is called the bias. The floated mineral is carried through the recovery zone on air bubbles which rise into the cleaning zone which is that column volume between the feed point and the overflow at the top. As the bubbles rise in this zone they are washed of gangue material by wash water which enters over the top of the froth layer. The froth layer is maintained at a given depth during flotation but this depth will depend on the froth cleanliness, for quite a bit of cleaning by wash water is accomplished in this layer."

Jan 1, 1988

By Thomas Clark

This report presents a review of the distribution and exploration potential of platinum-group elements (PGE) in Québec; it is based on published and unpublished analytical data. This qualitative evaluation of the PGE potential, whether in PGE-dominant deposits or in Ni-Cu-dominant deposits with co-product PGE, is based on interelement ratios such as Ni/Pd, Cu/Ir, Cu/Pt, and Cu/Pd. Good PGE targets, i.e., deposits associated with magmas fertile in PGE, are identified. Less favorable PGE targets, i.e., deposits associated with PGE-depleted magmas, are also mentioned. The importance of exploring for deposits similar to those at lac des Îles and East Bull Lake (Ontario) is emphasized.

May 1, 2001

By F. Y. Hsiao, H. C. Kao

Underground excavation in hard rock is normally stable at shallow depth except for wedge failure. However, the excavation depth is rapidly increasing recently. In high overburden stress condition, the integrity of rock would be destroyed with degrading rock strength. Therefore, understanding both the peak and the post-peak strengths of hard rock are necessary to assess the tunnel stability at depths. The characteristic of the post-peak strength is seldom studied in Taiwan in the past. Various estimation methods for the post-peak strength degradation were briefly reviewed in the paper. Based on the Geological Strength Index (GSI) system is widely used in the determination of the rock mass strength, the quantitative residual GSI system was adopted to estimate the possible strength degradation for a hydraulic tunnel in Taiwan. The Mohr-Coulomb model (no strength degradation) and the post-peak strength degradation model (strain softening model) were used to simulate the excavation of the case tunnel at different depths. The analyses demonstrate that the tunnel is in stable condition at 600m of depth. And the effect of the postpeak strength degradation on tunnel deformation is progressively significant with increasing tunnel depth. Approximate 3-5 times of increase in crown settlement and horizontal convergence would occur when post-peak strength degradation are considered at 2400m of depth. Severe tunnel deformation may endanger the tunnel stability. Modeling results reveal that the post-peak strength degradation has a great effect on tunnel stability under high overburden stress condition, which should not neglect in deep tunnel design.

Jan 1, 2015

By H. Karakul

Determination of P-wave velocity (Vp), which is closely related to intact rock, is a nondestructive, easy and less complicated procedure. Due to these advantages, there is an increasing trend to predict the geomechanical properties of rocks from Vp. In addition to mineral content, cementing material and porosity, degree of saturation (Sr) are also other factors influencing geomechanical properties of the intact rock. However, up to the present, in the studies on the prediction of geomechanical properties of rocks from Vp, the effect of Sr has not been investigated. By considering this issue, in this study, it was aimed to correlate strength properties (uniaxial compressive and tensile strengths) and Young’s modulus with Vp of various rock types under different degrees of saturation. In addition, geomechanical properties of rocks were estimated from theoretical P- and S-wave (Vs) velocities, which were calculated based on their mineralogical compositions. For this purpose, fourteen different rock types were collected from several parts of Turkey and a comprehensive laboratory testing program was conducted. In the statistical analyzes, a series of different prediction relationships were developed by using independent variables such as Vp, Sr and effective clay content (ECC). Simple regression analysis results indicated that although prediction of the geomechanical properties of rocks from Vp at different degrees of saturation was possible, the equations developed would yield some under- or over-predictions. On the other hand, the multivariate equations developed have very high prediction performances and are very useful tools to estimate the geomechanical properties from the measured Vp at any Sr value. In addition to mineralogy, the variation in geomechanical properties with increasing Sr is also associated with the combined effect of porosity and clay content, which is first described in this study by the term Effective Clay Content (ECC). It is also noted that strength properties of rocks at any Sr may also be estimated using the empirical relations based on the theoretical Vp and shear-wave velocity (Vs) values, which are calculated from their mineralogical compositions.

Jan 1, 2015

By L. Zhu, S. Kaierle, M. Dahmen, C. Zimmermann, T. Haubold, I. Kelbassa, C. Mattern

Application of integrally bladed disks (blisks) is of increasing interest in compressors of aero engines. Blisks are preferred due to their potential for size and weight reduction, for increased performance and for reduced manufacturing costs compared to conventionally bladed disks. In case of a damage the blisk aerofoils cannot be simply replaced. If the damage is beyond acceptance or blending limits refurbishment is possible only by scrapping the whole blisk assembly, or more cost effective by the application of advanced weld repair methods. Weld repair of blisk aerofoils is challenging as it affects a critical part with specific requirements regarding its mechanical integrity, and as the accessibility is usually limited. The paper describes the ongoing development of advanced weld repair processes as part of a comprehensive repair strategy which have been developed for small-sized blisk assembly to give competitive maintenance cost.

Jan 1, 2006

By J. H. Schloen

"One of the most important phases in Canada's relatively rapid development of its metal mining and refining industries was launched in 1928 when the directors of Noranda Mines Limited decided to establish an electrolytic copper refinery ""somewhere in Eastern Canada”. Noranda's president, J.Y. Murdoch, had already evolved the company's ""mine to market"" policy and was determined to prove the economic feasibility of refining Noranda copper in Canada. The time appeared to be ripe as buoyant business conditions continued into 1929. In addition, proven ore reserves at the Horne Mine in northwest Quebec had virtually tripled and the price of copper had reached a healthy 15 cents per pound. Letters Patent incorporating the company bearing the date February 6, 1929 had been granted by the Secretary of State in accordance with an application that specified a capital structure of $2 million divided into 20 000 shares with a value of $100 each. Noranda assumed 70% of the original investment in the proposed refinery, while the Nicholas Copper Company of New York (which later became Phelps Dodge Corporation) and British Metal Corporation Ltd. of London, England, each were responsible for 15%. Nicholas Copper Company agreed to supply the design and to supervise the construction of the refinery and British Metal Corporation would act as sales agent and market the refinery's products."

Jan 1, 1999

By George Kellock

In presenting this paper for discussion at the Western Annual Meeting to be held in Edmonton, it is with the idea of creating a full and general discussion by the mining men in the Province as to the best way to eliminate, or at least hold down to a minimum, the dangerous coal-dust which is made in mining pitching seams in our Alberta mines by the chute method. Also, an alternative method is outlined, whereby the percentage of lump-coal mined can be increased, and the mining costs reduced-although the paper does not go into any detailed consideration of costs. The general trend of mining practice and lay-outs is at present towards mechanization, and the results being accomplished by the substitution of machines for manual labour are fully justifying the changes. In the technical mining journals, there are published from time to time papers dealing with a variety of methods of mining, which are descriptions of actual operations, and a great deal of interesting and valuable data is given as to the comparative values of the different methods, insofar as the percentage of grades of coal produced, the cost of production, etc., are concerned; but the mechanical methods described in these papers are nearly always suitable only for flat seams, or seams with a very low inclination.

Jan 1, 1929

By Marc Piard

In a cool mine, tapping high-pressure lines through reducing valves lowers the temperature beyond remedy. It is the writer's suggestion that, for low-pressure work, law-pressure air ,should be generated in a compressor installed underground adjacent to the work, and that the jacket-water of the compressor should be utilised for re-heating purposes. Such a system of compressed air distribution, designed especially for service in cool mines, is described in the following notes. The suggested system includes a three-wire pole line from the sub-station to the opening nearest to the working face, with a cable connection extending to the latter from the openings; an electrical centrifugal unit; a reservoir excavated in the ground; and a distribution line, re-heated by jacket-water. As regards the reservoir, it may be pointed out that in many mines there are blind or abandoned tunnels that could be used for the purpose. The centrifugal type of compressed air machine is a comparatively new departure, and it was formerly considered that such a machine, operating at less than 1,000 kilowatts per unit, would be commercially impracticable. At the present time, however, these machines are being built in Europe for as little as 400 kilowatts per unit, and as much as 110 lb. per sq. inch pressure. One advantage which these centrifugal machines have over other types is that they may be driven by plain induction motors, without the help of special starters-a consideration of the first importance where the electrical regulations are severe.

Jan 1, 1926

By Rafic Moubarac

FRP (Fiberglass Reinforced Polyester) equipment has been used in different and several applications during metals processing and extraction, and the hydrometallurgical process. Case histories of such equipment will be shown of major projects worldwide.

Jan 1, 2015

By G. Vibert Douglas

It often happens that the field geologist encounters a fault in ground where there is little to guide him with regard to the throw, or vertical displacement, and the heave, or horizontal displacement. The following construction gives both of these components of the fault, and the writers hope that it may prove a help to others. The construction is applicable to both normal and reversed faults. Briefly the procedure is as follows: Take a point which is common to the faulted geological feature and to the fault plane and on the downthrow side of the fault. Move this point in the horizontal plane in the direction indicated by the fault striæ. Rebat the point down to the plane of the fault and obtain its throw. Next consider the other side of the fault and truncate it down by the amount of the throw just determined. Then project the line of the geological feature through to the trace of the fault-plane at the lower horizon. The result is the relative positions of the two parts of the original geological feature as severed by the fault. In Figure r, let us consider a typical normal fault, that is, a fault in which the hanging-wall has gone down relative to the footwall. This characteristic, or its alternative, the reversed fault, is determined by observation on the ground. Let AB be the line of any geological feature such as the edge of a dyke, vein, or bedded sediment. The plane of which AB is the trace may have any dip; in the present case let us say 70° right. Let FF be the trace of a fault-plane which may have any dip; let us say 35° left in this case.

Jan 1, 1928

By Ronald G. Hamm

"With the advent in Canada of large open-pit equipment, the associated wire rope required must keep pace, especially in design and construction, along with the field that leads to increased rope life.This paper will first describe the various types of shovels and draglines in use today and also the unique characteristics of the wire rope required to efficiently service this equipment.Emphasis will be placed on the special equipment and techniques required in the wire rope manufacturing, along with the maintenance procedures required for a profitable operation.IntroductionOpen-pit and strip mining is increasingly playing an important role in the Canadian mining industry.An integral part of the surface mining industry is the excavation equipment used both to strip the overburden and remove the actual orebody. Two of the more prominent pieces of equipment are the electric power shovel and dragline. These two types of equipment have increased significantly both In size and number over the last decade.Wire rope plays a significant part in the operation of these machine s. Proper selection of the correct wire rope as well as proper maintenance procedures, can result in a major saving of a mine's wire rope consumption.The most prominent ropes for shovels are the hoist ropes. Some shovels also employ crowd and retract ropes. Boom pennants are manufactured from both wire rope or galvanized bridge strand.The most prominent ropes for dragline excavators are hoist, drag, and dump ropes. Some dragline excavators have boom hoist ropes, and most large dragline excavators have a boom suspension system using galvanized bridge strand."

Jan 1, 1983

By F. Mackay, S. A. B. da Fontoura

"The theoretical solution for a viscoelastic well was presented by Gnirk and Johnson in 1964. From this an exercise was executed to validate the numerical simulation of a cemented salt well. The exercise comprised the geomechanical behavior through time of a cemented salt well, this was achieved using a finite element commercial software. This simulation showed the accuracy of the theoretical solution for viscoelastic materials such as salt rock. The theoretical solution presented elastic and viscoelastic analytic equations for the tangential and radial stresses. The equations for the elastic material (casing and cement) and for the viscoelastic material (salt rock) are presented here: Where equations 1a & 1b are the radial and tangential stresses of the elastic material; equations 2a & 2b are the radial and tangential stresses of the viscoelastic material; and a, r and b are the geometrical parameters explained in Figure 1. These equations are function of Pb, a stress time dependent factor that comes from the Burgers model of viscoelasticity. This is well explained in Gnirk and Johnson (1964) and for the sake of simplicity is not disclosed here. Po is the stress at section A-A’ dependent of the depth h."

Jan 1, 2015

By Yuki Koshino, Kenji Kaneko, Yasuhiro Aruga, Takuya Maeda

"In general, there is a strong correlation between dislocation characteristics and mechanical properties of aluminum alloys. In this study, dislocation characteristics of tensile deformed Al-Mg alloys were examined by transmission electron microscopy. An Increase in the solute concentration, ranging between 0.3 and 1.1%, Mg leads to increase in strength and decrease in uniform elongation. The accumulation of dislocations during the tensile deformation is observed in lower strain as the concentration of solute Mg in the alloy is higher. It is believed that the solute Mg in Al-Mg alloy promotes the accumulation of dislocation during the tensile deformation resulting in the decrease in elongation.INTRODUCTION The influences of the amount of Mg concentration on the tensile properties of Al-Mg alloys has been investigated by many researchers. It has been understood that the tensile ductility of Al-Mg alloy is higher for the Al-Mg alloys with higher Mg concentration beyond 2 mass% (Mukai, Higashi, Hirano & Tanimura, 1993). Uchida and Yoshida (1995) reported the formation of microbands during the tensile deformation due to the localization of dislocations, and the amount of microbands were reduced when the Mg concentration of the Al-Mg alloy was increased from 3 to 9 mass%. Their study suggested that the dynamic recovery of dislocation was retarded due to the increase of the Mg concentration during the tensile deformation, which resulted the increase in ductility. On the other hand, in the case of Al-Mg alloys with the Mg concentration less than 3 mass%, the reason why the ductility of Al-Mg alloys decreases with increasing Mg concentration has not been sufficiently investigated. In general, the Mg concentration used for automotive usage is less than 1 mass%, in the case of Al-Mg-Si alloys (Aoki, 2013). Therefore, to clarify the roles of Mg in the low concentration range on ductility of aluminum alloys and to elucidate its mechanism contribute to alloy design of Al-Mg-Si alloys having good formability."

Jan 1, 2018

By R. A. Sullivan

I T IS one of the unwritten policies at Preston Mines that we examine closely any method or tool that will help us in our constant battle against rising costs. It is our personal conviction that most work methods can be improved. Therefore even though the job went well yesterday, it does not necessarily follow that it should be done by the same method today. With the arrival of the natural gas pipe line in the Porcupine area it was obvious that we would have to take a good look at the possibilities of using this source of fuel for plant heating. • Steam presently generated at Preston is for heating purposes only, no process steam being required. Prior to the fall of 1960, the heating plant consisted of two low pressure, coal-fired, fire-tube boilers, operating at an approximate pressure of 14 pounds per square inch. These boilers were underfed by stokers and could be operated either singly or together. ~o. 1 unit was a horizontal return tubular boiler, registered at 100 h.p. No. 2 unit was a fire-box boiler, registered at 75 h.p.

Jan 1, 1962

By D. G. Minnes

Talc has been mined at Madoc since 1896, the oldest mine in continuous operation in Canada. Canada Talc Industries Limited operates the Henderson and Conley deposits by underground methods. A newly discovered East zone is being de veloped by open pit. The raw Henderson talc is a foliated talc schist of high purity and whiteness; Conley talc is a white talcose dolomite. Products are used primarily as fillers in paints, plastics and rubber.

Jan 1, 1984

By M. E. Holuszko

A research program has been carried out at the Mining Department of the University of British Columbia to study the effect of wettability of coal on its handleability and bulk density. The effect of moisture content on the bulk density of coal was found to be more pronounced for hydrophilic coals than for hydrophopbic ones. Altering wettability of coal surface leads to different effects of moisture on bulk density. The samples were studied at different fine fractions content, and it was shown that there was no effect of increased content of fines on the bulk density for hydrophobic coals, while for hydrophilic coals this effect was very significant. It was shown that the moisture content at which the lowest bulk density was reached coincides with the critical moisture content for studied samples, as determined from handleability tests using Durham Cone method. This critical moisture is the moisture content at which a sudden deterioration of coal handleability occurs. Based on the bulk density and handleability tests, the flow theory of moist coal is proposed.

Jan 1, 2006

By W. Curlook, V. G. Papangelakis, M. Baghalha

A pressure acid leaching process has been developed for the extraction of metal values, nickel, copper, cobalt and zinc, from base metal smelter slags. The basic concept contemplates cooling the smelter slags through solidification sufficiently slowly to induce a good measure of crystallization; and subsequently, after fine grinding, to pressure leach such slags at around 250°C while applying oxygen overpressure, utilizing smelter byproduct sulphuric acid. High levels of extraction of the slags' metal values are thereby achieved. It has been shown that if the same slags are quenched thereby producing an amorphous structure, the resulting metal extractions are very low. The process is applicable to smelting furnace throwaway/discard/dump slags, as well as to in-process converter slags. By extracting the bulk of the residual base metal values in the throwaway/discard/dump slags, the resulting leached residues are rendered virtually benign vis-à-vis the external environment.

Jan 1, 2004

By K. Ilankoon, I. M. Saman, S. J. Neethling

In heap leaching the transport of the acid from the drippers to the surface of the ore particles is a major factor in the overall performance of a heap. This flow behaviour is complex as the flow is unsaturated and occurs along a tortuous set of inter-particle channels and connections. The particle properties such as size, shape and porosity are very important when modelling the liquid holdup and flow within heaps, since the dominant mechanisms at work are quite different. This paper investigates the effect of these particle properties experimentally on heap flow behaviour using a 1-D column leaching system consisting of non-porous glass beads with a system of actual ore particles. The similarities and differences between the two systems on flow behaviour are described using an inter-particle flow model. In addition, the applicability of positron emission particle tracking (PEPT) for laboratory column leaching will be detailed to calculate hydrodynamic dispersion in packed beds compared to more conventional residence time distribution (RTD) tests and also to obtain the time averaged rivulet flow paths through the particles of the bed for the better understanding of heap hydrodynamics.

Jan 1, 2014

By John S. Stevenson

THE Twin "J" Mine, operated by Twin "J" Mines, Limited, represents an amalgamation of the old Lenora, Tyee, and Richard III mines (see Figure 1) on mount Sicker, eight miles by road, northwesterly, from the city of Duncan, on Vancouver island. These mines produced 253,000 tons of copper-gold ore between 1898 and 1909 (see Table I). During the more recent period of production from these properties, July, 1943, to May, 1944, Twin ?J? Mines, Limited, mined and milled ore with values mainly in copper and zinc, and minor values in gold, silver, and lead. Figures are not available for this later production. Field work at the property was started by the writer in 1941 and continued in 1943 and 1944.

Jan 1, 1945

By T. A. Chepushtanova, I. U. Motovilov, V. A. Luganov, G. D. Guseynova

"Kazakhstan has significant reserves of oxidized nickel ore with low nickel content. Processing of such ores is effective via pyrometallurgical technologies such as smelting to ferronickel or matte with consecutive extraction of metals from melting products. There are also many options for direct hydrometallurgical processing. However, they do not provide high nickel recovery.We studied extraction of nickel and cobalt by using combined technology of low-grade ore processing from the Shevchenko Kazakhstan deposit, which includes smelting to poor matte followed by hydrometallurgical processing of the matte. The nickel content in the initial ore was 0.75–0.9%. Pyrite concentrate of Sokolov-Sarybai Kazakhstan deposit containing 0.17% cobalt and 0.06% nickel had been used as a sulphidizer at smelting.As a result of the study, we were able to extract up to 98% of the nickel and up to 80% of the available cobalt. Obtained matte contained 3.1% nickel, 0.29% cobalt, 71.6% iron and 24.3% sulfur. Matte leaching was carried out by hydrochloric acid. The iron content in the pregnant solution was 170–185 g/dm3. Nickel and cobalt precipitation from the pregnant solution was carried out by hydrogen sulfide. Initial matte or cast iron was used as neutralizers during the process. Practically complete precipitation of nickel was achieved at 3–5% excess of neutralizer at 333–343°K in 4 hours; up to 95% of cobalt precipitation was achieved in 50% excess of neutralizer at 363°K in 8 hours. The purified solution contained 200–600 mg/dm3 of nickel, 80-100 mg/dm3of cobalt and 175–185 g/dm3 of iron. The purified solution allows to obtain iron oxides by high-temperature hydrolysis, and to regenerate hydrochloric acid.As a result of non-ferrous metals precipitation we obtained sulfide concentrate with concentration of Ni up to 25% and concentration of Co up to 5.5%. The technology is recommended for semi-industrial testing."

Jan 1, 2016