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By R. A. Campbell

The electric smelting of five lowgrade Canadian manganese ores has been investigated at the Mines Branch, Department of Mines and Technical Surveys, Ottawa. Ferromanganese, silkomanganese, and spiegeleisen were produced 1by special smelting processes from these ores since the latter were too low grade to be treated by conventional smelting methods. In one case the results were considered to be sufficiently promising to justify the construction of a pilot plant, by the Company concerned, for the further development of the process.

Jan 1, 1956

By Sarah Bélair, Denis Beltrami, Valérie Weigel

"Mabounié is a polymetallic deposit in Gabon containing niobium (1.2%), tantalum (0.03%), rare earth elements (REE) (1.4%) and uranium (0.03%) that are mostly carried by Pyrochlore minerals. Classical route for niobium recovery is a pyrometallurgical process that consists in pyrochlore flotation, dephosphorization of the niobium concentrate and aluminothermy to obtain ferro-niobium. Pyrochlore concentrates can also be treated by a hydrometallurgical process with a mixture of sulfuric and hydrofluoric acid leaching followed by solvent extraction to separate niobium and tantalum. However, the first process does not allow recovering REE and the second one is not environmentally friendly because of the use of HF.ERAMET is looking for new opportunities on strategic metals market and has recently developed a hydrometallurgical process for the recovery of all these metals based on a sulfuric acid treatment of the ore. After solubilisation of the valuable elements, niobium / tantalum are precipitated as a concentrate (12% w/w Nb and 0.3% w/w Ta) while REE (2.7 g L-1) and uranium (90 mg L-1) remain in solution. Nearly 90% of REE are recovered from the solution by conventional REE double salt precipitation [NaREE(SO4)2.xH2O) method but some REE still remain in solution as this method does not allow to quantitatively recover medium (Sm, Eu, Gd, Tb, Dy) and heavy (Ho, Er, Tm, Yb, Lu, Y) rare earth elements. From the different process routes studied (solvent extraction, precipitation, ionic exchange etc.), an innovative method has been developed and patented to recover REE residual concentration in solution. This is based on an aluminum removal step followed by precipitation of REE as REE phosphate concentrate (REEPO4) by phosphate addition into solution. The phosphate concentrate is then purified according to the conventional monazite treatment, i.e. caustic conversion and REE solubilisation in acidic media."

Jan 1, 2016

By C. J. Edmonds

Of the gold mined in Canada over 90 percent is extracted from the ore by the process of "cyanidation". In this process crushed ore is treated with lime to provide "protective alkalinity" and cyanide, usually in the form of sodium cyanide. The gold is dissolved in the cyanide solution, which after further treatments for clarification, is precipitated by the addition of zinc dust. Wastes from the process consist of tailings which will contain cyanides. Water consumption, mill size, effluent quantity and quality are depicted in transparency (1). It should be noted that as far as the wastes are concerned it has been impossible to postulate a typical situation. Variation from the above data will occur. A summary of data from tailings pond effluents is presented in transparency (2). The figures in parentheses indicate the usual range of values for the parameter.

Jan 1, 1973

By C. A. Young, H-H. Huang, L. G. Twidwell

Solid particles, especially oxides/hydroxides, develop an electrical charge on their surface when submerged in aqueous solution. Parks was able to relate PZC (point of zero charge) of an oxide to its minimum solubility and isoelectric point. Dzombak has compiled an extensive database for adsorption reactions on ferrihydrite surfaces using the double layer theory. The equilibrium calculational program, STABCAL has been used to extend the considerations of Parks and Stumm. The PZC for many hydroxides, complex oxides, and non-oxides have been investigated and the results are reported in the literature. Removal of arsenic and metals by adsorption on ferrihydrite as the substrate has been computed using ST ABCAL and the computational results are compared to experimental data. Absorbents other than ferrihydrite such as aluminum hydroxide are also discussed.

Jan 1, 2005

By S. Kelebek, B. Ingram, C. Gibson, T. MacNeil, M. Aghamirian

"The beneficiation and upgrading of pyrochlore from its ores is carried out through flotation. In industrial practice, upgrading is conducted in a two-stage flotation process in which pyrochlore flotation is carried out after gangue mineral pre-flotation (carbonate, silicate, sulphide or phosphate reverse flotation). In this study, the flotation of pyrochlore from a low grade carbonatite ore was performed at the laboratory scale following a two-stage flotation process in which carbonate minerals were floated in advance of niobium minerals. In parallel, a simplified flotation process was developed in which pyrochlore was floated directly from gangue minerals at increasingly acidic pH. Laboratory results indicated that both two-stage and direct flotation provided similar results in terms of niobium grade-recovery. Based on these results, a large scale, integrated pilot plant was conducted using a direct flotation flowsheet. While the elimination of reverse gangue flotation resulted in flowsheet simplification, the dissolution of carbonate minerals and the subsequent effect of dissolved cations on the floatability of pyrochlore added an element of complexity. A comparison of results from locked-cycle laboratory testing and pilot plant testing highlights the challenges of scaling up a complex flowsheet. A case is made for the direct flotation process and the key parameters to achieving success in large scale direct flotation of pyrochlore are discussed.INTRODUCTIONPyrochlore (Ca,Na)2Nb2O6(OH,F) is a niobium bearing mineral which has been the primary global source of niobium since the first pyrochlore mine commenced operations in the late 1960s (Gibson et al., 2015a). Preceding the discovery and development of high grade pyrochlore deposits in North and South America, the majority of global niobium supply came from gravity concentration operations of columbite (Fe,Mn)Nb2O6, across Africa (Perrault and Manker, 1981)."

Jan 1, 2016

By G. Hu, P. Chang

"As hydraulic fracturing is forbidden in some countries due to its accompanying environmental pollutions, microwave fracturing was proposed as a substitute technology to enhance coal seam permeability. Its mechanism includes: on the one hand, thermal stress caused by non-uniform microwave heating leads to fracture development in coal body, which increases coal seam permeability for gas; on the other hand, moisture within the coal body that hinders gas desorption and diffusion is removed during this process. To study the effect of moisture content on fracture development under microwave irradiation, high resolution photographs were taken before and after microwave treatment. These photographs were then binarized and skeletonized. Based on the processed photographs, the total area were calculated using ImageJ. The results showed that coal samples with 0% and 25% water saturation have more variation in fracture development as compared to that of samples with 50%, 75% and 100% water saturation. This study can be very useful in gas drainage and gas control in coal mines. INTRODUCTION Coalbed methane (CBM) is a clean energy source as well as a natural hazard to underground mining (Kurnia, Sasmito, & Mujumdar, 2014; Ranathunga, Perera, & Ranjith, 2014). One of the main goals of mine ventilation is diluting methane and removing underground contaminants (Xu, Huang, Nie, Chalmers, & Yang, 2017). Coalbed methane (CBM) has to be extracted prior and during underground mining to avoid methane outburst and explosion accidents. However, with the increase of mining depth, the coal permeability decreases significantly, which makes it hard to extract the methane (Huang, Xu, Hu, Kizil, & Chen, 2018). To enhance the coal seam permeability, many CBM recovery methods have been applied on-site, such as hydraulic fracturing and enhanced coalbed methane (ECBM). However, hydraulic fracturing is restricted due to environmental concerns and ECBM is only suitable for the coal seam with relative large permeability (Bustin, Bustin, Chikatamarla, Downey, & Mansoori, 2016; Huang, Xu, Chen, & Chen, 2018; Huang, Xu, Hu, et al., 2018)."

Jan 1, 2019

By Elaine Ellingham, Francis T. Manns

"Abstract -The Orostar and Scadding were two small gold mines owned and operated by Orofino Resources Limited. Conventional statistical treatment indicates an identical arithmetic mean grade of 0.22 oz/T Au for both mineable reserves. Further, the deposits are both shown to have cut weighted average reserve grade of 0.21 oz/T. Orostar mined out at 0.206 oz/T and Scadding at0.156 oz/TAu . The combined exploration and development database contained 1394 fire assays, more than enough for statistical confidence in a normal distribution. Therefore this study was initiated to determine, if possible, why the mill head grades were lower than the averages and to experiment with several methods to determine whether a reliable statistical mill head grade estimation method would emerge. Despite the identical reserve grades, distinct differences in the grade distribution histograms are present. By studying the arithmetic and log-normal grade distribution s, with some attention to South African practices, this paper reports on those differences which may account for the considerable divergence in the mill head grades. Furthermore, this study casts considerable doubt on the industry standard method of cut weighted averages.The global mill head grades of the two deposits have been derived from the arithmetic average grades by graphic means. This precise method of mill head grade prediction, if applied to complex orebodies, could permit selective grade control and result in direct cost savings by allowing the operator to detect false value stopes, benches or levels and emphasize reliable regions of not only gold mines, but also uranium or base metal deposits."

Jan 1, 1992

By Brad Bjornson, Geoff Stevens, Mike Ashar, Cliff Britch

"LocationThe facilities are located 30 km north of Fort McMurray, Alberta (or 470 km northeast of Edmonton, Alberta).Brief Description of OperationThe operation includes the mining of oil sands, extraction of bitumen from the oil sands, and upgrading of the hydrocarbon fraction prior to shipment via pipelines to refineries.HistorySuncor was initially called Great Canadian Oil Sands. It was started by Sun Oil of Philadelphia. Construction began in 1965, with the first production coming on September 1967.Details of Present Milling Practice (Plant 3)Plant 3 recovers bitumen from the oil sand using the Clark hot water process. The basic steps in the process are conditioning, primary recovery, secondary recovery and tailings oil recovery.Oil Sand Feed SystemThe oil sand feed from the mine is transferred to the feed bin in extraction by two conveyor systems. Oil sand analyzers on each conveyor system measure the amount of bitumen and fines in the ore. Cones at the bottom of the feed bin distribute the oil sand to five process lines. Feed flow from each cone is regulated by an apron feeder which transfers the oil sand to conveyors that discharge into the conditioning drums. Weightometers on each of these five conveyors measure the rate at which the oil sand is delivered into the drums. The oil sand feed rate to each drum can be adjusted by varying the speed of the apron feeders."

Jan 1, 2000

By Robert Drummond

Away back in the eighties of the last century, when Sir Charles, then Doctor, Tupper, was not only a prominent but a dominant figure in the political life of Nova Scotia, his opponents brought the railing accusation against him that he was the foremost of egotists because of his frequent use of the personal pronoun. I heard Tupper speak and had no sympathy with the railers, because I could not well see how the pronoun could be dispensed with without laying himself open to a charge of affectation. I shall make reference in what follows to incidents in which I have taken part, and shall be at no pains to dispense with the pronoun, even though thereby I lay my-self open to the charge of being a pupil of the deceased states-man. EVENTS LEADING UP TO THE ORGANIZATION OF THE PROVINCIAL WORKMEN'S ASSOCIATION The Springhill Mining Company began development work at Springhill in the early seventies of last century. So vigorously was the work prosecuted that in 18 7 4 two slopes, the east and the west, were in active operation, with a considerable. output, the east slope on occasional days producing 800 tons. The President of the Company, the late Senator McFarlane, was a Nova Scotian, the other directors were mainly merchants from St. John, N.B. From the first the enterprise was an .astonishing success, due in the greatest part to its geographical position, and in large part to the untiring vigilance of the directors, a majority of whom visited the collieries at short intervals, thereby keeping the manager, much of the time, on tenter hooks.

Jan 1, 1924

By Gyan S. Rajhans

"The strategy of fibrous dust sampling is discussed, various sampiing methods are critically reviewed .and their application to coal dust is demonstrated. Fibre counting is described in detail. An attempt is made to explain the basis of determining the threshold limit value of asbestos and other dusts. The paper also discusses such dust control methods as enclosure of the process, effective local exhaust ventilation, segregation, substitution, wet processing and continuous monitoring of the return air for recirculation."

Jan 1, 1970

By Peter M. Power

A microscopic study was made of a series of simultaneous slag and metal samples taken from a low carbon basic open hearth heat. An attempt was made to identify the various micro-constituents found. As the various impurities in the bath are oxidized, the metal structure changes from that of high-phosphorus white cast iron to that of low.-carbon steel. A detailed study of phosphorus distribution is included. The acid run-off slag has an .acicular orthosilicate structure which changes on 'shape-up' to a very basic tri-calcium silicate and calciuim ferrite structure. Many unidentified minor constituents are present in the slags. Though metallography will never replace chemic.al analysis of the bath, the microsopic study of polished slags has some promise of being useful in slag control work.

Jan 1, 1956

By X Dai

This paper investigated the loss of cyanide via oxidation in CIP or CIL processes by relating the cyanide oxidation to its major oxidation product, cyanate. The results showed that the oxidation of both free cyanide and copper cyanide complexes are substantially enhanced by the presence of carbon. The rate of cyanide oxidation was found to occur in the order: Cu(CN)32- > CN- > Cu(CN)2-. The cyanide oxidation rate in the presence of copper and carbon increased significantly with increasing dissolved oxygen concentration, typical of CIL vs. CIP conditions. Cyanide oxidation rate of iron, zinc or nickel cyanide complexes was minimal.

Jan 1, 2011

By The Staff

IT is a high compliment to be invited to present a pap::r on the subject of "Mining in the National Economy". To cover it adequately would need the knowledge of the economic geologist and of the technical mining engineer, together with the arts of the statistician and of the economist in general, allied with generous psychic powers. Further, one should embellish the tale with a touch of drama. It is comforting that the subject is so broad that whatever may be said within the compass of a paper like the present, can hardly be criticized as going beyond the terms of reference. A conventional approach would be to begin with the noteworthy statistics of the mining industry of yesterday and today. But in the present company this would be "carrying coals to Newcastle"-or to give the venerable metaphor local colour, "nickel to Sudbury". Such statistics are available in all their stimulating detail in our official publications. Let us tackle at once, therefore, as a less hackneyed theme, the relationship of mining to other phases of the Canadian economy. RELATION TO TOTAL PRODUCTION While mining occupies a position of less importance than manufacturing or agriculture in Canada, its relative contribution has greatly increased during the post-war period. Due to the fall in wholesale prices, the net value of production in Canada has shown a decrease averaging about 1.5 per cent per year during the post-war period, though its volume of course has gone up. Mineral production on a value basis, on the other hand, showed a gain of 2.8 per cent per year. Mineral production was only 5.14 per cent of the net value of production of all kinds of commodities in 1919, bur from 1929 to 1936 the proportion rose steadily rill it reached no less than 12. 76 per cent in the latter year.

Jan 1, 1937

By Georgia J. Lysay

Kemess South Mine ended operations in March 2011. Final reclamation works began during operations in 2008 in anticipation of closure. The focus of reclamation during mine operations was on the inactive areas of the tailings dam, waste rock dumps, and expended borrow areas. The general reclamation strategy for the Kemess Mine site marries long-term erosion control with successional reclamation principles. For disturbed areas, this requires application of growth media, proper preparation of surfaces, and introduction of native pioneer plant species to initiate successional processes of recovery. Tailings are retained behind an earthfill dam of approximately 140 m in height, with a crest length in excess of 1 km. Reclamation activities at the dam have included placement of growth media, specialized surface preparation and construction of diversion ditches. The final closure spillway is currently being constructed, with completion scheduled for summer 2011. The two main waste rock dumps contain segregated non-acid generating (NAG) waste rock and potentially acid generating (PAG) waste rock. Resloping of the NAG dump for long-term stability commenced in 2009, followed by placement of growth media and ground preparation. The PAG waste rock will be fully relocated into the expended open pit for final, permanent subaqueous disposal.

May 1, 2011

By Xiaozhu Chen, Qi Ping, Pu Yuan, Qinyong Ma

"In order to investigate the fractal feature of coalmine deep rock fragments under impact loads, variable cross-section split Hopkinson pressure bar apparatus, 50 mm in diameter, was adopted to conduct impact compressive test for rock specimens from -962m deep coalmine. Various impact pressures, such as 0.3, 0.6, 0.9 and 1.2MPa, were selected to implement different loading rates. Sieving statistical analyses were conducted for rock fragments after being impacted, and the particle size distribution of broken rock in various loading rates were calculated with the fractal method and then the corresponding fractal dimension was obtained. Test results shows that there is a good self-similarity and fractal feature in fragments distribution of deep coalmine sandstone under impact loads. The fractal dimension of fragments is between 1.9 and 2.7. The research also indicates that there is an approximate power relationship between dynamic compressive strength and fractal dimension, and a strength power relationship between fractal dimension and average strain rate. Moreover, there is a linear relationship between fractal dimension and specimen absorbed energy. The rock fractured process can be quantitatively described through fractal dimension, which can reflect the deep rock broken degree and is an ideal index to evaluate the distribution of rock fragments.INTRODUCTIONBroken rock is one of the most basic processes in mining operations, rock fragmentation has always been an important index to evaluate rock breaking effect (Xu & Yu, 1984). Macroscopic fragmentation of rock material is the final results of continuous development, expansion, gathering and cutthrough of internal micro-cracks. This process, developing from microscopic damage to macroscopic fragmentation, is an energy dissipation process and shows fractal characteristics (Xie, 1993). Turcotte (1986) has conducted statistical analyses of fragmentation for different kinds of geological materials under various broken conditions, and arrived at the conclusion that fragmentation distribution is a fractal."

Jan 1, 2015

By F. Crundwell, N. Steenekamp

"The leaching of sulphide minerals generates a significant amount of energy. There are three systems that might be used to remove this energy. These are: cooling coils, quench water, and flash recycle. Flash recycle is the recycling of slurry from the autoclave to the feed tank. Heat is removed in this arrangement when the slurry at elevated temperature and pressure is flashed to atmosphere, releasing steam. The slurry is returned to the autoclave at lower temperature, resulting in cooling. The cooling is directly proportional to the steam released from the recycled slurry. Design equations and results for the flash recycle system are presented. A fourth proposal for removing heat is to recycle slurry from the back of the autoclave. These four alternatives not only remove the heat, but also have an effect on the leaching efficiency. Amongst the four alternatives, design calculations indicate that the flash recycle option is the optimal solution in terms of leaching efficiency and heat removal, and recycling product from the back of the autoclave is the worst. In spite of its efficiency in terms of heat removal and leaching, the implementation of the flash recycle system is limited to a few operations in the platinum industry.INTRODUCTIONIn considering ways to improve leaching operations, focus is placed on the chemistry, on the kinetics, the agitation and perhaps even on the gas mass transfer conditions. Attention is less frequently placed on the removal of energy from these reactors and how this might limit performance.The pressure leaching of sulphides releases a significant amount of heat. For example, the reaction for the leaching of chalcocite, Cu2S, given by"

Jan 1, 2012

By L. A. Mells

"A laboratory test program was initiated by the Department of Energy, Mines and Resources as part of the National Uranium Tailings Program to investigate the applicability of a radium selective ion exchange complexer for removing radium from Canadian uranium mining effluents. The test program was carried out by Melis Consulting Engineers Ltd. under contract to the Department of Supply and Services using the Saskatchewan Research Council facilities located in Saskatoon, Saskatchewan.The results of this work showed the ion exchange complexer, Dowex XFS 43230.00, to be efficient in removing radium from contaminated water of uranium mining operations with the ultimate loading capacity of the resin on one type of water treated being determined as approximately 1,600 Bq/cm3 of new resin. Although this resin has potential application for treatment of effluent streams in uranium operations it has been identified that the resin efficiency and capacity is directly related to the chemistry of the water being treated and site-specific testwork is required in order to establish reliable design data for full-scale operations.IntroductionThe possible applicability of a radium-selective ion exchange complexer for removing radium from Canadian uranium mining effluents had been identified and discussed as a possible alternative to present radium removal methods during a review of disposal technology options for the National Uranium Tailings Program of the Department of Energy, Mines and Resources(1). Work by other workers(2.3) had shown the complexer to be very efficient in removing radium from contaminated water. Also, plant trials on contaminated minewater at the Mt. Taylor uranium mine in New Mexico is reported to have shown the resin complexer to be efficient under plant operating conditions.As a result, a laboratory test program was initiated by the Department of Energy, Mines and Resources as part of the National Uranium Tailings Program to investigate the suitability of this resin for Canadian uranium mining effluents. The test program was carried out by Melis Consulting Engineers Ltd. (MCEL) under contract to the Department of Supply and Services using the Saskatchewan Research Council (SRC) facilities located in Saskatoon, Saskatchewan."

Jan 1, 1985

By A. D. Yell

"Recovery of water is always a major factor in the Beneficiation process. As Preparation Plants become larger the recovery of water for reuse, is a critical cost consideration. Tema Isenmann Inc in conjunction with our sister Company Multotec Manufacturing, has over the years, developed numerous different Screen Panels, Sieve Bends and Static Screens for dewatering. This paper will focus on a new innovation, the TeePee™ Panel which has double the open area of conventional Screen Panels. This results in efficient dewatering (reduced filter cake moistures) which allows for the use of smaller Vibrating Screens or increased capacity on existing Vibrating Screens. A major factor in the efficiency of any Screen Panel, including TeePee™ Panels, is the performance of the Vibrating Screen. If the Vibrating Screen does not have the required gravitational force or screen area to drain it will not dewater efficiently. Therefore a holistic approach has to be taken where the Vibrating Screen needs to operate at an optimal level, in conjunction with the correct Screen Panels, to achieve efficient dewatering. Key performance areas for Vibrating Screens are therefore detailed in this paper with an emphasis on important dewatering criteria. Case studies of different dewatering applications are included, where the use of TeePee™ Panels, has shown a marked improvement over conventional flat Screen Panels in reduction of filter cake moisture content.INTRODUCTION Dewatering can be done in a number of different ways and is largely dependent on the ore type, the particle size distribution and to what extent one needs to dewater will determine the method used. There are a number of different dewatering methods that can be used for particles above 200 micron, including Screen Bowl Centrifuges, Filter Presses, Static Screens, Static Sieve Bends and Vibrating Screens. This paper will focus primarily on Vibrating Dewatering Screens showing improved drainage and a reduction in the filter cake moisture content. KEY PERFORMANCE CRITERIAL FOR VIBRATING DEWATERING SCREENS For clarification the critical key performance criteria for Vibrating Dewatering Screens are set out in this paper. Dewatering Screens Vibrating Dewatering Screens are normally linear motion, either horizontal or inclined at 5 to 7° upwards with a vertical or back sloped plate at 45° to the rest of the screen deck. The back plate will often have screen panels in them to increase the dewatering capability, as shown in Figure 2 below."

Jan 1, 2017

By R. W. Coburn

The results of field experiments on wells which required stimulation indicated that engineered well-completions will cause an increase in ultimate recovery at reduced costs. Techniques and tools have been developed which can be used to establish well conditions most conducive to successful stimulation. Cementing, perforating and treating are bound together so completely that the success of one phase is completely dependent on the .effectiveness of the preceding phase. A method of determining the efficiency or effectiveness of any given well-stimulation treatment has been derived. Pressure behaviour during a treatment can be analyzed to yield the total percentage of the formation which has been treated.

Jan 1, 1960

By A. Eslami

When producing high grade mattes in smelter plants, copper losses in the slag are inevitable. Hence, the recovery of copper from slag has been the focus of many research projects, copper flotation being a widely used process. In the Khatoonabad converter, 200 t/d of slag are presently produced with a grade of 2.3% Cu. Assuming a 85% recovery by flotation, about 3.9 t/d copper could be produced, which is of prime importance economically. In the present work, a sample of this slag was crushed and ground in the laboratory to liberate the copper-bearing minerals. Following mineralogical studies, optimum laboratory flotation parameters were obtained, resulting in 90.27 % recovery and 9.42% of copper grade for the rougher stage. At pilot scale, a pulp of 28% solids was floated at ph 10.5 using 40 git of Z6, 25 git of R407 and 20 git of MIBC and A65. A recovery of 83.52% was obtained for a concentrate grade of 28.36% Cu. In the rougher cells, the feed consisted of particles 94% finer than 74 microns whereas in the cleaning stage, particles were 95% finer than 44 microns. Based on the obtained results, the Sarcheshmeh Khatoonabad converter slag is presently being fed to the Chargonbad flotation plant, where a concentrate of 32% copper at 86% recovery is being produced.

Jan 1, 2007