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By Mostafa Benzaazoua, Bruno Bussière, Jean Lelièvre

De nombreuses opérations mimères exploitent et traitent des minerais sulfurés pour concentrer des métaux precieux (Au, Ag ... ) OU des métaux de base (Cu, Pb, Zn ... ), laissant en fin de parcours des tonnages considérables de résidus plus ou moins générateurs de drainage minier acide (DMA) selon leur contenu en sulfures. De nos jours, Jes restrictions en matière de protection de l'environnement obligent Jes opérateurs miniers a trouver Jes solutions Jes plus efficaces pour préserver Jes sites environnants de la pollution due a l'oxydation des sulfures. Cette oxydation cause une acidification accrue du milieu et une mise en solution des metaux toxiques. L'utilisation des recouvrements multicouches est l'une des solutions Jes plus efficaces pour limiter la pollution liée au DMA mais entraine des coilts de construction qui sont souvent considérés par l'industrie miniere comme prohibitifs. Une façon de rendre cette technologie applicable, d'un point de vue économique, est de désulfurer Jes résidus à l'usine de traitement et d'utiliser la fraction inerte comme composante d'un recouvrernent multicouche. Cette opération de desulfuration peut etre réalisée par flottation non sélective des résidus dans le but d'obtenir d'une part un faible volume de concentré de sulfures qui devra être géré convenablement et d'autre part un rejet non générateur d'acide.

Jan 1, 1998

By A-A. Bogno, M. Rappaz, J. Valloton, H. Henein

"Rapid solidification of Al-Cu droplets of eutectic composition was carried out using Impulse Atomization in an argon atmosphere, to study the microstructures forming at different cooling rates and undercoolings. Two distinct morphologies were observed within the investigated Al-33wt%Cu droplets microstructures: (i) A regular lamellar morphology and (ii) an undulated morphology. The volume fraction of each type of morphology was measured as a function of the droplet size and the nucleation undercooling was deduced using the hypercooling limit equation. The scale of the microstructures was determined through measurements of inter-lamellar spacing across and along the growth direction. Growth velocity and undercooling were deduced using Jackson and Hunt (1966) eutectic growth theory. Finally, mechanical properties were estimated through micro-hardness analysis using a Vickers hardness tester, revealing exceptional properties for an aluminum-copper alloy. Indeed, the hardness values, increasing with growth rate and undercooling, were 3 times higher than the values obtained in hypo-eutectic Al-Cu alloys.INTRODUCTION Eutectic alloys are very attractive due to their good fluidity allowing ready shaping of parts in casting processes as well as in thermal spray deposition. In addition, they yield microstructures with high mechanical properties, by the virtue of their scale/size which is defined by the solidification parameters and the thermodynamic and thermophysical properties of the given alloy. Therefore, it is important to understand the relationship between the microstructures and the solidification parameters of eutectic alloys in order to control their solidification path and mechanical properties. The latter could be improved by either adding an appropriate strengthening component to a base eutectic material (Böyük, MaraslI, Kaya, ÇadIrlI, & Keslioglu, 2009) or by refining the microstructures for more effective dislocation pinning (Campbell & Campbell, 2003). Tailoring the microstructure can also be beneficial to chemical (Freitas, Osório, Spinelli, & Garcia, 2014; Osório, Freire, Caram, & Garcia, 2012) or electrical (Kaya, 2012) properties of the material. Eutectic-type microstructures, usually formed from liquid (eutectic transformation) or solid (eutectoid transformation), are made up of two or more different phases, generally of lamellar or fibrous (rod like) morphologies (Kurz & Fisher, 1998). In general, a binary eutectic structure can be regular (when both phases are non-faceted) or irregular (one of the two phases is faceted), the two solid phases having roughly the composition of the liquid from which they are formed."

Jan 1, 2017

By Farzad Khodabakhshi, Adrian P. Gerlich

"In this article, cold spraying process was utilized to coat the surface of AZ31 magnesium alloy with a layer of AA7075 aluminum alloy. Thereafter, friction-stir processing (FSP) was employed to enhance the microstructure and consolidate the deposited layer. The grain structure and phase morphology were studied along with indentation hardness before and after cold spraying and friction stir processing. The magnesium substrate had an initial hardness of 74 HV which increased to 102 HV after FSP due to refinement of grains to <2 µm. The aluminum coating layer, provided improved surface hardness up to 160 HV, which further increased to 173 HV after FSP was applied.INTRODUCTION Cold spray is a material deposition process which can be used for surface modification, since it deposits material on a metallic substrate with little heating by way of high velocity ballistic impacts. Using cold spray technology, it is possible to deposit a wide range of coatings with various thicknesses by controlling the characteristics of the feeding powder and metal substrate, gas temperature, gas pressure, powder feeding rate, nozzle geometry, and gun traverse velocity. This process has been recently employed for surface modification in various aircraft and automobile structural applications. This has led to a broad range of research using this process for production and modification of different metallic and non-metallic systems. In the present study, cold spray process was used to deposit a uniform layer of aluminum-zinc alloy (AA7075) on the surface of AZ31 magnesium alloy. This coating was subsequently treated by way of friction-stir processing (FSP) as a new post-spraying modification technique to enhance the structural homogeneity and densification of the coated aluminum layer. This method utilizes a non-consumable rotating tool with a specially designed shoulder and pin that is plunged into the surface of metal to be modified and then moved along the direction of interest. The localized frictional heating between the rotating tool and workpiece leads to softening of the materials around the pin, and material extrusion through a complex flow of material from the advancing toward the retreating side the tool. To the author’s best knowledge, only a few reports discuss the modification of a cold sprayed deposit by FSP process. The microstructure and mechanical properties of the cold sprayed layer and substrate before and after FSP modification were examined using optical observations (OM) and indentation hardness testing. Furthermore, the AZ31 alloy substrate alone was treated with FSP as well, for the aim of comparison to the processed coating."

Jan 1, 2017

By K. Iturralde

The article discusses the possibility of automation in refurbishment processes of social dwelling built from 1950 to 1970. These massively produced buildings were mostly designed prior to the law enforcement regarding thermal insulation or accessibility. Nowadays, many of these buildings are being retrofitted. The article focuses on the works in the external envelope. The task of renewing the whole social building stock is big and it requires a systematic process that facilitates a rapid upgrading, without neglecting the specific situation of each case. How could an automatic refurbishment process of these buildings be defined? The process should start with the data collection of the building and the creation of a 3D model using software such as BIM. The project, drafted in 3D, should facilitate the manufacture of building elements by robotics. In turn, it should be noted that during the assembly at the site, the pieces must be fixed quickly and efficiently. Is it possible to implement an automated process for the refurbishment of apartments built in the second half of the twentieth century? To approach the answer, a virtual refurbishment project is performed. The article focuses on the rehabilitation of the building envelope. Furthermore, it gives special attention to the double skin facade. It is well known that a second skin in this type of building can be an element that integrates several functions. Finally, needless to say that refurbishment of residential buildings is a need in our society. By extending its life cycle, robotic refurbishment provides more favorable socioeconomic and environmental capabilities than the sole construction of new buildings.

Aug 1, 2013

By Xiaoqi Sun

"Rare earth elements (REEs) have a series of specific properties making them invaluable in products including lighting, electronics and magnetism. The elements have been used in many commercial products, for example, turbines, electric vehicles, batteries, lighting, computers, cell phones and lasers. Heavy REEs are attracting the interests of scientists from many countries, and these elements have become critical to develop high-tech materials. Ion-adsorbed rare earth deposits were first discovered in China. The minerals are also called weathered crust elution-deposited rare earths. The particular types of deposits are distributed throughout southern China. The ion-adsorbed deposits are rich in medium and heavy REEs, accounting for more than 80% of the world’s total medium and heavy REEs production. However, the separation of heavy REEs from ion-adsorbed deposit is difficult owing to their similar chemical properties. The conventional separating technologies have caused serious pollution. A novel extraction strategy has been developed in this laboratory and is presented herein.INTRODUCTIONThe unique properties of rare earth elements (REEs) render them important in high-strength magnets, lighting phosphors, polishing compounds, and ceramics. Especially for applications that take advantage of the f-orbital electrons, substitutions outside the REE family are often difficult to impossible (Nassar, Du, & Graedel, 2015). Extracting and separating individual elements from mined ore is not easy, requiring lengthy operations to separate them, and this results in high costs and adverse effects on the environment. The low concentration of REE in the earth’s crust makes economic exploitation difficult (de Boer & Lammertsma, 2013) and the sustainability of the REEs separation industry has aroused considerable attention (McLellan, Corder, Golev, & Ali, 2014). To eliminate protons and break the dimmers in organic phosphonic acids or carboxylic acids, the saponification of acidic extractants by acid-base neutralization reactions are widely used in industrial REEs separation (Sun, Luo, & Dai, 2012a). The saponification procedure contributes to increased extractability and selectivity of acidic extractants to a considerable extent. The common industrial saponification mechanisms and technological processes are shown in Figure 1 and include ammonium saponification (saponified by NH3·H2O), sodium saponification (saponified by NaOH), calcium saponification (saponified by Ca(OH)2), and magnesium saponification (saponified by MgO). These inevitably result in wastewaters containing NH4 +, Na+, Ca2+ or Mg2+ because of the cation-exchange extraction mechanisms (Xiao, Long, Huang, Feng, Cui, & Wang, 2013; Song, Fu, Wang, Liu, Zhou, & Li, 2014; Sun & Waters, 2014)."

Jan 1, 2016

By Chas. L. Emery

"The laws of rock mechanics apply equally well to all rock structures, and open pits are not exceptions. The concepts and some arguments about the emphasis to be placed on various aspects of open-pit design are discussed in this article.RocksROCK can be described as a granular material consisting of grains and glue. The grains may be fragments of other rocks or polycrystalline aggregates. The glue may be ferruginous, calcareous, argillaceous, siliceous or other material connecting the grains. In a crystal intergrowth, the outer layers of the crystals in contact with each other may be considered to act as a glue. Water may be a glue in clay or a grain in a crystal structure. Air and other fluids or gases are grains if they occupy spaces in a granular mass. Such grains are functional either chemically or mechanically or both."

Jan 1, 1966

By Ben Sheneider

AT THE Flin Flon plant of the Hudson Bay Mining and Smelting Co., Limited there are two types of multiple hearth furnaces used in the roasting of sulphides. This pa-per will deal primarily with the wedge-type furnace in the roasting of zinc concentrates. The other furnace, the Nichols-Herroshoff type, is used in the copper smelter and is described in the papers given by (1) J. H. Ambrose in 1935 and (2) R. E. Mast and G. H. Kent in 1954. The design and operation of these roasting furnaces at the present time is essentially the same as given in the write-up in 1954. No at-tempt will be made here to describe these furnaces, except to mention that there are five Nichols-Herreshoff multiple-hearth furnaces, four of which are used to roast a dried mixture of copper concentrate, zinc plant residue, and flux, before this material is fed to the reverberatory furnace.

Jan 1, 1961

By G. Goodall, M. Muinonen, R. Pandher, R. Jabbar, S. J. Muinonen

"The implementation of a new and highly efficient converting practice at the Glencore Sudbury Integrated Nickel Operations Smelter has opened the possibility to further capacity increases by using larger ladles. To quantify the impact of increasing ladle sizes from 200 to 300 ft3, XPS constructed a detailed discrete event simulation using the commercial software package Rockwell Arena®. The challenges associated with implementing a model on an intricate and tightly scheduled process, and the solutions needed to derive meaningful results will be presented. The aisle capacity is predicted to increase by approximately 17 %, with a reduction in furnace tapping demand of 8 %. Arena modeling capabilities and the key factors contributing to the overall capacity increase at the Sudbury INO Smelter will be reviewed and presented.INTRODUCTION The Glencore Sudbury Integrated Nickel Operations (INO) comprises two Ni-Cu-PGM mines, Strathcona Mill, and the Sudbury Smelter. The Smelter has operated continuously since 1929 using different processes to produce nickel-copper Bessemer matte. Feeds to the Sudbury INO Smelter are a blend of concentrate from Strathcona Mill, Raglan concentrate produced at the mine-mill complex in Raglan, Quebec, as well as third party concentrate feeds shipped to Sudbury from around the world. In 2016, the Sudbury INO Smelter produced 75,900 tonnes of nickel and 20,000 tonnes of copper in Bessemer matte. The product matte is shipped to Glencore’s Nikkelverk refinery in Kristiansand, Norway where it is refined to produce nickel and copper cathode. A schematic of the Sudbury INO Smelter’s flowsheet is shown in Figure 1."

Jan 1, 2017

By Olaf Kessler, Jan Kalich, Michael Reich, Julia Osten, Uwe Füssel

Modern automobile bodies consist of different materials, e.g. aluminium alloys and high strength steels. Mechanical joining, e.g. clinching, is very suitable for joining aluminium and steel sheet. But clinching needs a sufficient ductility, which is no longer supplied by high strength steels. Laser-assisted clinching has been shown, to be able to join aluminium and high strength steel sheet successfully. Thereby the steel sheets were heated locally for short times to increase their ductility. Due to the thermal contact between steel and aluminium sheet the aluminium alloys also achieve a local short-time heat treatment. This fact may cause a significant impact, as aluminium sheet in automobile bodies is often used in T4 (or similar) condition and later artificially aged during the paint bake cycle. Aluminium alloys 6016 and 6181 have been short-time heat treated with heating rates up to some 100 K/s. Precipitation and dissolution processes have been monitored in-situ by calorimetry. Mechanical properties have been investigated on as well as after short-time heat treatment by deformation dilatometry. The results show, that suitable short-time annealing parameters during laser-assisted clinching can increase ductility and at the same time act as retrogression for aluminium sheets, resulting in increased strength after aging.

Jan 1, 2015

By D. Murray

A 2-hectare uranium tailings area has been reclaimed. The exposed tailings of 1.4 hectares were capped with glacial till and vegetated with grasses and legumes. The water running through the tailings was diverted around the tailings in a line ditch and treated with sodium hydroxide and barium chloride. Difficulties occurred in placing the till capping because of the low bearing strength and the uneven surface of the tailings. This led to varying thicknesses of till and the need for manual labour in some areas. Total reclamation costs were $32,200, with vegetation establishment costs at $13,700 per hectare. This report provides a record of work for use in assessing the long-term suitability of these treatments.

Jan 1, 1979

By W. Basuki, B. Setyotomo, L. Hakim, R. Hendrajaya

Due to high crack sensitivity of slab product of gas and oil line pipe application, its steel making process and alloy composition were evaluated and then improved to overcome its critical solidification process and reduced surface defects. The study was conducted at Slab Steel Plant Krakatau Steel. The purpose was to improve slab surface quality by reducing surface defects so that the slab surface doesn&apos;t need to be totally repaired. The method applied was by performing plant trial process, which the secondary process parameters such as alloying method and the casting parameters such as casting powder selection, metallurgical cooling, mould level control, and superheat were continuously monitored and then adjusted to the surface quality of the product. Based on the calculation of Ferrite potential of the steel, the chemical composition was designed to achieve optimum casting parameters in order to avoid high shrinkage during solidification. The results of the study are decreased surface defect quantity, and smooth casting process. The quantity of crack decreased by almost 90%. The slab surface repairing was significantly reduced from 85. % to less than 10%. These new casting parameters and developed alloy composition are then used and standardized for the mass production of the steel.

Jan 1, 2005

By C. Prévost, V. Leclerc, R. Pinto, M. Ruel

"A buffer’s ability to dampen production variations is directly related to its size. Small buffers cannot handle large variations in production, resulting in production losses when their inventory is depleted or saturated. This paper presents a predictive control algorithm used to regulate the inventory in a buffer of limited size, subject to large production variations caused by an upstream batch process. The algorithm was designed to manage the acid flow rates in an acid regeneration process, servicing batch leach reactors at Rio Tinto Fer et Titane, in Sorel-Tracy, Québec. The objective was to increase production by reducing equipment downtime caused by imbalances in the acid tanks servicing the leach reactors. The controller attempts to maintain acceptable acid tank volumes by optimizing the leach reactors acid/slag ratio and reaction time as a function of anticipated acid needs, all while maintaining product quality.INTRODUCTION Some beneficiation processes in extractive metallurgy require processing bulk material in batches. Typical examples of metallurgical beneficiation batch processes are smelting, leaching, electrowinning, elution and carbon-in-pulp. These processes are often situated midstream in an ore beneficiation flow sheet and either receive or transfer ore to continuous processes. Batch processes, by their very nature, introduce large variability in the flow sheet, because they process large finite quantities of material at nearly periodic time intervals. In order to dampen variations in production, various buffers–tanks and stockpiles–are utilized to accumulate ore upstream and downstream of batch processes. A buffer’s ability to dampen production variations is directly related to its size (Phillis & Gumede, 2011). Small buffers cannot handle large production variations, resulting in equipment downtime when their inventory is depleted or saturated (Everett, 2010, Berton et al., 2013). Consequently, the batch equipment production rates must be adequately managed to minimize production losses, attributed to depleted or saturated inventories, while maintaining product quality. Algorithms that anticipate or predict future production variations are often utilized to regulate buffer inventories, subject to large flow rate variations (Salvo et al., 2002; Bonvin, 2013). This paper presents a predictive control algorithm used to maintain an acceptable volume in a spent acid tank servicing several batch leach reactors. The algorithm is implemented at the acid leach plant of Rio Tinto Fer et Titane, in Sorel-Tracy, Québec."

Jan 1, 2017

By Julia Pflieger, Manfred Russ, Johannes Gediga

This paper shall show an economic feasible approach to implement Greenhouse Gas (GHG) reduction measures into the mining and metallurgy industry. The goal to improve energy consumption is directly linked to the reduction of GHG emissions and therefore directly in correlation with the economic viability. A baseline scenario of the considered reference system and of the respective reference year has to be defined, mapped and analysed. In a second step an analysis of the same operation using available and prospected Best Available Technology (BAT) processes is carried out to generate a basis for a benchmark system. The identified reduction potentials are reported and the GHG emission reductions are put into relation to the investment cost of the new process technologies / process adaption to be implemented. This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap implementation into the company&apos;s business operations. The GHG reduction roadmap is developed using ratios between GHG reduction and investment / operating cost to get an indication for a sequence for implementing carbon emission reductions measures.

Jan 1, 2010

By Chris Brothen

The introduction of new technology in mine operations has provided real opportunities for increased efficiencies and production gains which translate into enhanced profits. Computing and network technology usage has become integrated into surface mining operations and on average these investments in technology have proven beneficial for efficiency and productivity improvements. Embracing new technologies however, does not guarantee positive results. The expectations or improvements derived through the technology must be confirmed and clarified well before implementation. Tire Pressure and Temperature Monitoring Systems are an excellent example of an existing technology that can provide full time automated performance measurements of tires operating under harsh conditions and environments. Prompt warnings or alarms signaling when a tire has exceeded operating capacities will provide savings through lowered maintenance costs and increased productivity. To truly quantify the projected savings in tire life, fuel consumption, and increased levels of production, all costs associated with the technology, both direct and indirect must be considered. Apart from the initial cost of the system implementation, ongoing maintenance and support costs must be considered as well as the costs of system integration into existing mine operations

May 1, 2008

By Norman M. P. Low

"IntroductionIndustrial applications of mica utilize two commercially important varieties of mica: muscovite and phlogopite. Muscovite mica is a potassium mica with a general chemical formula, H2KA1(Si04)3 h, and is sometimes referred to as a potas hsilicate. Phlogopite is a magnesium mica having a general chemical formula, H2KMgSi(Si04)3, and is distinguished from the muscovite mica by its decomposition in sulphuric acid.Canada is one of the major natural mica producers in the world. A large tonnage of the mica powders is at present mined and processed in the Eastern Townships of Quebec. This Canadian mica is of the phlogopite type. A closely related mineral of the mica family which is widely used in the construction industry is vermiculite. It is a dehydrated magnesium-aluminum-iron silicate characterized by a foliated structure. Expanded vermiculite, which is often referred to as exfoliated mica, is used as many types of thermal and acoustic insulation, as loose fill in buildings, as an aggregate in concrete, as an ingredient in plaster and insulating concrete , and in fire-proofing compositions. Natural phlogopite and muscovite mica powders are used extensively as reinforcing agents in organic polymers. They also have a wide range of applications in commerical products. For example, dry-ground mica powders are used in large tonnage as a surface finish in roofing materials and as a bonding agent in wallboard joint cement. Common products such as paint, rubber, plastics and welding rods contain mica. Recent studies have also shown that mica powders can be added to portland cement in the preparation of concrete products, as they could improve the tensile strength of the concrete products. The potential and possible"

Jan 1, 1982

By G. T. Lapidus, A. Garcés, O. J. Restrepo

"Colombian nickel laterites have historically been processed by pyrometallurgy. However, due to the depletion in ore grades, alternative processes are required. Hydrometallurgical processes, such as pressure acid leaching, have been proposed as alternatives to extract nickel from deposits with suitable characteristics. Such a leaching process requires high concentrations of acid to achieve acceptable extractions, and is not selective. In this study, an alternative aqueous alkaline glycine system has been employed to evaluate the leaching behaviour of a Colombian nickel laterite which contains 1.15% Ni, 0.12% Co and 41.1% Fe. Additionally, the effect of the addition of chloride ions, the use of a reducing agent and the application of a pre-treatment to improve the extraction of nickel were evaluated. Extractions of 4.63% Ni, 42.16% Co and 0.33% Fe were obtained using a 1M solution of glycine at pH 9. In addition, an increase in nickel extraction from 4.63% to 25.68% was achieved by applying a pre-treatment to the sample. The results show that even though nickel dissolution was much slower than in acid leaching, it was selective over other metals such as iron, proving the proposed method to have potential as a process for the extraction of nickel from Colombian laterites.INTRODUCTION Before 2010, most of the industrial operations used pyrometallurgical processes for the extraction of nickel, mainly in saprolitic regions of deposits, with greater contents of the metal. Nevertheless, due to the gradual depletion of such deposits, different hydrometallurgical processes have been studied as alternatives to process those nickel laterites with low grade and those which present problems of refractoriness due to the presence of acid consuming materials (McDonald & Whittington, 2008; Oxley & Barcza, 2013; Wang et al., 2012). However, such leaching processes require high concentrations of acid to achieve acceptable extractions and they are not selective. Facing lateritic nickel ore deposits containing high levels of acid consuming materials, an alkaline leaching medium becomes an advantageous alternative over acidic media, due to the increase in selectivity and decreased corrosiveness and reagent consumption (Tanda, Eksteen, & Oraby, 2017). Unlike conventional acidic reagents used for metal recovery, alkaline reagents can selectively dissolve the desired metal, leaving in the solid residue other elements such as iron, magnesium and aluminum, which are problematic in subsequent stages of metals separation and recovery. Furthermore, there are no serious corrosion problems associated with alkaline leaching, even at higher reagent concentrations, or at elevated temperature and pressure (Ntumba Malenga, Mulaba-Bafubiandi, & Nheta, 2015)."

Jan 1, 2017

By P. C. M. Knops, K. Rijnsburger, R. M. Santos

To overcome the challenges of mineral CO2 sequestration, this work utilizes a unique proprietary Gravity Pressure Vessel (GPV) reactor technology, and focuses on reaction products of high economic value. The GPV provides intense process conditions through hydrostatic pressurization and heat exchange integration that harvests exothermic reaction energy. Here, laboratory-scale tests of the envisioned process was performed in tubular and continuously stirred tank reactor (CSTR) autoclave reactors. The mineral used was Olivine (~Mg1.6Fe2+0.4(SiO4) + ppm Ni/Cr), although asbestos, steel slags and oil shale residues are also under investigation. The effect of several process parameters on reaction extent and product properties was tested: CO2 pressure, temperature, residence time, additives (buffers, lixiviants, chelators, oxidizers), solids loading, and mixing rate. The products (carbonates, amorphous silica and Chromite) were physically separated (based on size, density and magnetic properties), characterized (for chemistry, mineralogy and morphology) and tested in intended applications (e.g. as pozzolanic carbon-negative building material). Economically, it is found that product value is the main driver for mineral carbonation, rather than, or in addition to, the sequestered CO2. The approach of using a GPV and focusing on valuable reaction products could thus make CO2 mineralization a feasible and sustainable hydrometallurgical process.

Jan 1, 2015

By R. C. Wallace

Introduction At a time when the mineral-bearing areas in Manitoba are being fi very keenly explored because of the major developments which are now taking place in that Province, it may be timely to give an analysis of the mineralization in the two major types of deposits, with a view particularly to assist in the intensive prospecting to which the mineral-bearing areas in the Province are now to be subjected. As is already well known, there are two principal types of mineral deposits in the territory- copper-zinc and gold; and attention will be confined almost exclusively in this paper to these two types, with some indication of such modifications of the main types as may be found to be of economic value. The details of the paper are drawn from what is yet a small part of the area of the Province available for prospecting. Enough is now known of the types of mineral deposits which are described in the following pages to justify the expectation that these types may serve as criteria in the search in the newer districts. Doubtless new types will also be found as investigations proceed.

Jan 1, 1928

By Ron Davidson

"The Utility Mine in southeast Saskatchewan is owned by Saskatchewan Power Corporation and operated by Mana/ta Coal Ltd. Up to 3.3 million tonnes of lignite is supplied annually to Saskatchewan Power's Boundary Dam Generating Station. The coal occurs in two predominant seams which are covered by up to 37 metres of saturated fine-grained overburden. Overburden is removed by two draglines working in two pits. Coal is hauled to the mine mouth power station. Comprehensive drainage and reclamation programs are integral parts of the operation. IntroductionThe Utility Mine is owned by Saskatchewan Power Corporation and operated by Manalta Coal Ltd. It is located in southeastern Saskatchewan, approximately 200 km southeast of Regina and 8.5 km southwest of Estevan (Fig. 1). The climate of the Estevan area is semi-arid with long, cool winters and short, hot summers. The mean annual precipitation is 42 cm and the mean summer temperature is 20°C; mean winter temperature is -10°C. The Utility Mine supplies coal to the adjacent Boundary Dam Generating Station. Increases in the station's generating capacity during the past decade have resulted in an extensive expansion program for the Utility Mine. This expansion program, the geological conditions present in the area, and the mining/reclamation operations will be highlighted in the following sections<1.2). History The Estevan area has a long history of coal mining. In the early years, coal was mined via entries into coal seam outcrops along the slopes of the Souris River valley. Surface strip mining was introduced in the late 1920s and progressed to the point where it totally replaced underground mining by the 1950s. Surface mining methods are currently used exclusively by all of the Estevan area operators."

Jan 1, 1985

By J. Mullins

Coal was first banked by the Dominion Coal Company, Limited, in 1898, near No. 2 Colliery, the same site as is presently used for that purpose. Though today there are banks at Glace Bay, Sydney, and Sydney Mines, these notes, except when otherwise desirable, will be confined to describing the practice as developed at the No. 2 Banking Station, Glace Bay, as being typical of methods obtaining at all sites. Storing The manner in which the coal was piled is illustrated diagrammatically in the accompanying sketch. A train of coal was brought on the main trestle, which extended the full length of the banking ground at a height of 22 to 39 feet above the natural surface, and dumped into bins which were integral with the trestle work. Chutes from these bins permitted the coal to be fed into 3-ton cars, which were horse drawn laterally on narrow gauge tracks laid about 10 ft. centres, to a maximum distance of 400ft. from the trestle. These cars were end-dump and as the pile extended laterally the narrow gauge tracks were lengthened by shorter or longer filling pieces, so that their ends were always kept at the brow of the bank. Much coal, however, had to be dumped directly on the tracks and hand trimmed to fill the valleys, and level off, between the tracks.

Jan 1, 1931