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By W. L. Hunter

The preparation of coal for the commercial market is a study both varied and wide, and can be viewed from many angles and in different ways. This short paper can but touch upon the subject and is intended to discuss briefly preparation plants which in some cases would seem to be quite inadequate. The conditions confronting most operators are similar, inasmuch as the existing plants were not built specifically to prepare a product for the market of today, but rather of yesterday. The tremendous strides made in the field of combustion in recent years require that the product be of the highest grade procurable, and in a glutted and somewhat restricted market the buyer may be more pernickety than otherwise. These would appear to be the conditions of today. Where a mine is operated individually, better all-round results seem more readily procurable than in a consolidated effort where so many different conditions are sure to arise demanding cognizance, and in many cases requiring to be incorporated in the scheme of things. In the case of a number of mines being administered to form a central source, that source not having had anything to do with the bringing into being of the institutions over which it presides, we find some of the mines well equipped with facilities to properly screen and load the coal, while in others the facilities are not so good, but are doing their share towards delivering a product that will pass muster and in such quantities that they can be counted on.

Jan 1, 1930

By E. W. Vekris

Patents are playing an increasingly important role in the business world. A diverse patent portfolio can enable a company to secure a monopoly within the market, which can provide a competitive advantage over competitors. At the same time, possessing a diverse patent portfolio greatly increases the value of a company's intangible assets. This paper provides an overview of the patenting process as it pertains to the fields of metallurgy and mining, and summarizes some general patenting strategies. A review of new "green technology" initiatives recently adopted by Patent Offices around the world is also provided.

Jan 1, 2011

By Pierre Laliberté

L?utilisation de plusieurs nouvelles technologies et systèmes de contrôle visant des économies d?énergie dans une exploitation minière pourrait laisser croire qu?il suffit d?additionner les économies potentielles de chacune de ces technologies pour en évaluer l?économie totale. Une addition simpliste des pourcentages d?économie pourrait, dans certains cas, dépasser 100%, ce qui est évidemment totalement incohérent. Les LMSM-CANMET sont à réaliser une étude dont les résultats serviront à estimer l?influence de certaines technologies et systèmes de contrôle visant des économies d?énergie et à évaluer l?impact des unes sur les autres. En outre, un modèle de simulation est en cours de création afin d?évaluer les gains incrémentaux liés à l?application d?une série d?innovations dans une exploitation minière. La présentation fera le point sur l'état d'avancement du projet en plus de soumettre quelques exemples.

May 1, 2007

By H. McIntire, R. Preston, D. Roberts

"Repeated 3D terrestrial digital photogrammetric surveys were conducted on hard rock mine pillars to characterize damage during secondary mining. Damage was quantified by measuring Depth of Failure, DOF, from spalling material and crack intensity, D21. These damage values were then correlated to visually assessed Pillar Damage Ratings and numerically estimated pillar loads. Measured damage, particularly Depth of Failure, correlated well with Pillar Damage Ratings. Numerical predicted pillar stress vs. damage exhibited the expected trend with shorter pillars being stronger. High resolution photographs and 3D models were also used to characterize damage mechanisms, which were found to be structurally constrained. INTRODUCTIONThe Doe Run companies Southeast Missouri Operations consists of six room and pillar lead mines (Brushy Creek, No. 29, Casteel, Buick, Fletcher and, Sweetwater) (The Doe Run Company, 2014). The mines are hosted in the Carbonates and Shales of the Viburnum trend with mining depths varying from 180 to 300 m. Pillars are commonly cut square with widths varying from 7 to 9 m and heights generally between 5 and 18 m, resulting in extraction ratios between 80 and 85% (Roberts et al., 1999). Figure 1 presents an idealized stratigraphic section through the Viburnum trend and Figure 2 shows a plan view of the five areas spanning the three mines included in this study."

Jan 1, 2015

By R. A. King, B. G. Hunt, C. E. T. White

"This paper reviews the history, occurrence, properties, and uses of indium, and describes the commercial production and fabrication of that metal by The Consolidated Mining and Smelting Company of Canada, Limited (Cominco), at Trail, B.C'. Indium is produced commercially at Trail from dross retreatment furnace D.R.F.) slag, a complex by-product of the lead smelting operations. Furnace feed prepared from this slag is smelted with coke and limerock in an electric furnace. The e1ectric furnace bullion is parted electrolytically, producing a market-able lead-tin alloy containing about 8 per cent tin, and leaving the indium in the anode slime. Recovery of indium from the anode slime involves roasting the slime with sulphuric acid, followed by leaching with water, purifying the leach solution, recovering the indium by sponging with zinc or aluminum, and re-fining electrolytically. This process yields standard grade (99.97+ per cent) indium which is either sold or refined •to high purity ( 99.999 per cent) indium for special uses requiring higher purity metal."

Jan 1, 1959

By Zdenek D. Hora

British Columbia is an important producer of a variety of industrial minerals for both domestic and export markets. Some commodities such as limestone, dolomite, gypsum, calcium carbonate, silica, barite and magnetite are raw materials for well-established industries located in British Columbia, Alberta and northwestern USA. Others, like magnesite, sulphur, jade, asbestos, dimension stone and clay products, are mainly exported in processed form to overseas customers. Companies are developing markets for relatively new mineral products, including pumice, volcanic cinder and zeolites. A number of attractive geological targets have been identified by industry while research by government geologists has outlined the potential for refractory minerals, gemstones, garnet, nepheline syenite, carbonatites, residual kaolin, igneous apatite and peat.

Jan 1, 2001

By J. H. Brown

"THE need for continuing education has been recognized only in fairly recent years as a major concern of the engineering profession. Formerly, it was acknowledged that engineers were required, at least informally, to follow the professional literature and to give some attention to new technical and technological developments. However, those relaxed days, when progress could be followed in a casual or incidental evening of reading, have disappeared in these days of mushrooming information. The engineer is now in the position of the man trying to control the flow from a fire hydrant with a child's pail. Our problem is that of developing an effective flow system -be it trough, hose, pipe or a bigger pail.The first step in achieving an effective means for continuing the education process is to realize that the need for the system is really an outgrowth of an increasingly sophisticated society. It is merely one more symptom of that society; others would• include the facts that new engineering graduates are more highly trained than those of several years ago, that graduate schools are now the norm and that even some fairly recent technologies are becoming outdated. There-fore, let us examine the education-al systems from which the bulk of the increasing sophistication has grown."

Jan 1, 1966

By Jon Errey, Aleksandar Petrovic, Karl Haase

"Developing a gold deposit of this magnitude in the Amazonian jungle of Guyana posed many challenges. This paper describes not only the process & logistical challenges arising from the remote mine site location in a tropical environment with a local industry unaccustomed to recent large scale gold mining operations, but also the innovative technical solutions employed to address the unique ore body characteristics. The best examples of this approach were dealing with the initial high clay content saprolite ore from the development phase and primary mining pits whilst ensuring that the design also implemented the right method to deal with the future fresh rock in an environmentally sensitive habitat. In order to do this separate individual crushing flowsheets were generated, focusing on the specific material handling equipment that would be suitable to handle these various types of material and ensure high recoveries were maintained.INTRODUCTIONAurora gold mine is located in forested region of Guyana, 170 km west of capital Georgetown, and 130 km West North-West of Bartica, a settlement at the junction of the Essequibo and Cuyuni Rivers.The Aurora gold project (Aurora) is a 5,000 tonne per day open-pit/underground operation, which will produce a total of 3.29 million oz. gold – averaging 194,000 oz. per year – over an initial 17 year mine life. At the final investment decision in 2014 Aurora had a total resource of 6.54 million ounces in the measured and indicated categories (62.83 million tonnes at 3.24 g/t Au) as well as additional 1.82 million ounces in the inferred category (16.93 million tonnes at 3.34 g/t Au)."

Jan 1, 2016

By G. A. Vissac

In this paper we intend to deal particularly with the economic side of coal washing as it applies to our mines. We will then discuss why the dry-cleaning process has been selected, and give a brief description of our plant, dwelling only on its specific features and referring the reader to the numerous papers published on the subject for any details on the principles and machinery used in dry cleaning. ECONOMIC DISCUSSION The washery introduces an extra cost for depreciation, operation, and loss in treatment. A certain proportion of the coal, now being sold, and which the miners have been paid for. will have to be wasted. As a whole, the total increase in cost would be approximately 60 cents per ton. On the possibility of recovering this amount depends the success of the washery. There are two advantages to be expected from the washery, the first, which occurs at the mine and which will be certain; the second, more difficult to estimate, because it depends upon convincing our customers that they should pay more for a better product.

Jan 1, 1924

By W. D. Haley

The report of the Forestry Committee, presented to the recent Imperial Conference at London, is discouraging in its view of the future of timber resources and supplies. From a review of the forestry situation throughout the world, there is every likelihood that, thirty years from this, a shortage of the soft-woods will be severely felt. In the United States, only about one-third of the present forest area contains virgin timber. This will be cleared at the rate of five and a half million acres a year, so that in twenty-five years it will be about all gone. Canada has only about 27 per cent of her original forests left, and her virgin soft-wood will last but another half century. At the present time, the value of her lumber products is over $300,000,000 annually. During the summers of 1909 and 1910, the Government of Nova Scotia caused an examination to be made of the forest conditions in this Province. The reconnaissance, which was under the direction of Professor B. E. Fernow, of Toronto, involved an examination of the various soils, the rate of growth of the wood, and a general survey of the forest area. The importance to the Province of conserving its forest resources was clearly shown, and a number of recommendations were made, which; however, were never acted upon.

Jan 1, 1927

By Reik M. Winkel

Radar Technologies are successful implemented in the military industry since decades and recently found their way in the mining industry as level gauge radars for bin applications. The latest generation of microwave radar sensors are capable to provide geometrical data of the surrounding area of mining machines, too. Radar sensors are an improvement to laser scanners as they are more robust and able to penetrate dust and mist. Radar sensors will be the key source for operator assistance systems. indurad and RWTH Aachen University conducted a large series of tests at open pit mines and underground coal mines to determine the potential of the new two dimensional Dual Range Radar iDRR. Several applications were determined as highly feasible and are now completed respectively in the implementation stage. The authors are giving an insight in the experimental results, the implementation and an outlook of future applications for this technology.

Oct 1, 2009

By R. Daignault et G. O. Allard

The Chibougamau area represents a part of the Abitibi greenstone belt. The rocks constitute a volcanic pile (Roy Group) overlain by a volcano-detritic sequence (Opemisca Group). Three important periods of tectonic deformation have been distinguished. The first one produced folds with north-south horizontal axes. The second one is responsible for the isoclinal east-west folds, and the associated regional schistosity. Reverse faulting contemporaneous with this period of deformation, produced two distincts effects. In some cases the faults cause a repetition of the stratigraphic sequence. Whereas in others the faults truncate second period folds. Domes and basins interference pattern are produced by the superposed effect of Di and D2 deformations. The motion of these two periods would be more or less contemporaneous. The deformation could be generated by rising diapirs of early plutons combined with the progressive formation of troughs by gravitational subsidence of denser strata. The rising diapirs of late granitoid plutons produces a wraparound of the host strata.

Jan 1, 1984

By J. Visman

The water cyclone washer has a number of advantages that makes it a desirable machine for the cleaning of fine-grained and friable materials such as 1,4 x 0" slack coals. In this paper results are presented of tests carried out on a shaly coal containing a high percentage of inter-grown materials from the Minto area, New Brunswick. The tests were con-ducted in the pilot plant of the Western Regional Laboratory in Edmonton. The test results show that the cleaning characteristics of this coal can be improved by lightly grinding the recirculating middlings fraction, which constitutes approximately 30 per cent (1.45-2.00 fraction) of the raw feed. • The cleaning of 1;4 x 0" fines by water cyclones compares favourably with other coal cleaning machines and has an added advantage of being extremely simple to operate, low in capital and operating cost, and high in capacity. The application of water cy-clones dates back approximately ten years, following its development at the Dutch State Mines. ( 3) A number of papers published d

Jan 1, 1961

By K. L. Azinger

Successful relationships between mining companies and local stakeholders are now an essential part of the social contract of “doing business” (Prescott, 1995). The methodology presented in this paper is designed to assist mining companies in understanding and building relationships with diverse stakeholder groups. The methodology starts by recognizing that mining projects have a natural life cycle which can be used to identify when new external affairs strategies are required. In designing an external affairs strategy, the first step is to set objectives that are compatible with the overall objectives of the mining project. The management team then identifies the main stakeholder groups and seeks to understand the priorities and inter-relationships of the individual stakeholders. The result of this stakeholder analysis is an understanding of the Degrees of Influence of each of the stakeholder groups along with a relationship map which illustrates the strong interactions between stakeholders. The company is then prepared to take a proactive approach to building relationships with the primary stakeholders. This methodology was developed by BHP to assist with the federal government environmental approval process for the development of Canada’s first diamond mine. BHP has successfully used the methodology in three different phases of the NWT Diamonds Project and is now applying the methodology to mining and development projects around the world.

Jan 1, 1998

By Horace Freeman

The sulphur consumed in Canadian pulp mills and acid plants is worth approximately three million dollars annually and amounts to one hundred and fifty thousand long tons, all of which is imported from the United States. Concurrently with a decline in the value of newsprint there has been a gradual increase in the price of this raw material. Most pulp mills in Canada are situated within reasonable distance of domestic pyrite deposits; nevertheless it has not yet been found possible to mine these deposits and utilize the contained sulphur in competition with the imported material. It is the purpose of this paper to elucidate the reasons therefor, and to describe? a commercial-scale experiment undertaken with the object of introducing a native raw material into the Canadian pulp industry on the purely economic basis. Reasons for the Preferred use of Sulphur The known sulphur deposits in the United States are very large, so that at least a twenty-year supply of this material is assured. It is recovered cheaply and in pure condition. Although large deposits of pyrite are known in Canada, nothing has yet been developed to compare in size, cost of mining, or purity with the United States material. It has been necessary to handle and transport more than two tons of pyrite to equal a ton of sulphur.

Jan 1, 1930

By W. J. Blackstock

Introduction To The great majority of people, the term 'strip coal' has little or no meaning, or if it has any significance it is thought to refer to a poor grade of coal that had to be accepted during the war because no other fuel was available. Few people in the Province of Alberta realize the magnitude of our coal stripping industry, and fewer realize that strip coal has been available to domestic consumers for at least forty years. Among the first in the field of strip coal mining in Alberta were the Tofield Coal Company, Ltd., and Sterling Collieries Company Ltd. It was not until the advent of World War II, with its huge drain on industrial and domestic coal sup? plies produced by the underground mines, that some other source of coal was seriously sought. The tremendous shortage of manpower du ring this period of National emergency made it imperative that any increase in the coal production must be procured on a high tonnage per man-hour basis. It was therefore natural that the highly mechanized strip mine should be eagerly encouraged and subsidized by the Governmental agency - the Emergency Coal Production Board - under the very able direction of Mr. G. A. Vissac.

Jan 1, 1949

By D. A. Jacobson

Mining operations, whether new or existing, are constantly looking for ways to maximize production and improve energy efficiency, while keeping the footprint required to a minimum. The Nordberg MP1250 cone crusher was designed with these three goals in mind. A series of side-by-side evaluations comparing an MP1250 to an MP1000 were completed at two Freeport-McMoRan operations. The first evaluation began October 2009 in a tertiary position and the second began March 2010 in a secondary position, where it remains in full production today. Utilizing 25% higher power capacity than the existing MP1000 tertiary crushers, the MP1250 had 29% higher capacity and 17% lower specific energy, adjusted for differences in feed and product size. The MP1250 compared to the existing MP1000 secondary crushers achieved 30% higher capacity at a slightly reduced specific energy, while achieving a finer product. The MP1250?s higher capacity and energy efficiency may have application in many crushing plants. Depending on site specific economic factors, greenfield projects may benefit from a smaller footprint and less ancillary equipment, whereas brownfield projects may benefit from higher capacity or a finer product within the same footprint.

Jan 1, 2012

By Helge B. Wurst, Michael P. Cipold, Jan F. Bachmann, Claus C. Bachmann

"In washability, the objective is to establish the set of maximum possible separation performance criteria for a given mineral feed. The method of choice for this has been the conventional sink-float analysis. Time, cost and safety aspects of the sink-float method have prompted the search for a new approach for establishing separation performance criteria, especially as performance levels of separator plants can be maximized if reliable information based on an analysis of washability in conjunction with particle size distribution, elemental constituency becomes readily available. The new method to establish washability and associated performance information utilizes at least two measurement technologies concurrently: single energy x-ray transmission and image processing. For porous or very inhomogeneous materials the results can be refined further by using dual energy x-ray transmission and image processing. The value of the collected data increases considerably if the washability data were additionally available in time to be considered in the control of the process plant. The incorporation of an automated washability monitor gives near real-time data that would impinge positively on the profitability of the plant operation. The method was extensively tested with a range of sample with different densities, varying from 1 g/cm³ (coal) to 5 g/cm³ (iron ore).INTRODUCTIONWashability of minerals like coal and iron ore is expressed by a curve or graph showing the results of a series of float-and-sink tests. Several of these curves are drawn to illustrate different conditions or variables, usually on the same axes, thus presenting the information on one sheet of paper. Washability curves are essential not only for the design but also for the operation of preparation plants.In determining the washability analysis, particle density is the underlying feature of all washability curves. Conventionally, the particles are separated into density fractions by immersing them in fluids of a predetermined density followed by skimming of those particles that stay afloat. The particles remaining afloat thus have a density lower than that of the fluid they were subjected to. The particles that remained at the bottom of the fluid container thus had a higher density higher than that of the fluid. By progressively increasing, for example, the density of the fluid and immersing the remaining particles so as to be able to skim the next density fraction, the particles would be fractionated into density groups. The liquids used range from aqueous solutions to organic liquids to suspensions. Unfortunately the liquids used for this separation process are often toxic and expensive. It stands to reason that a new method of determining washability is sought."

Jan 1, 2016

By Chuan-Jian Zhong

Gold-based nanoparticles in the size range of a few nm have attracted increasing interests in catalysis, sensors and biomedical applications. The study of the unique catalytic properties of nanosized gold was inspired by the pioneering work of Haruta on the nanogold-catalyzed CO oxidation (1-4). There have been a number of excellent reports discussing both fundamental and application aspects of gold nanoparticles in catalysis (3-8). Our work reported herein is aimed at investigating the preparation and application of gold and its alloy nanoparticles for potential applications in fuel cell catalysis. Fuel cells operating by electrochemical oxidation of hydrogen or methanol fuels at the anode and reduction of oxygen at the cathode are attractive power sources due to their high conversion efficiencies, low pollution, lightweight and high power density. While methanol offers the advantage of easy storage and transportation in comparison with hydrogen fuel cell, its energy density (~2000 Wh/kg) and operating cell voltage (0.4 V) are much lower than the theoretical energy density (~6000 Wh/kg) and the thermodynamic potential (~1.2 V). The poor activity of the anode catalysts and inefficient activity or issue related to "methanol cross-over" at the cathode electrode are associated with the loss of about one-third of the available energy at the cathode and the other one-third at the anode. Extensive studies have been focused on Pt-group metals (Pt+Pd+Rh+Ru+Ir (PGM)) for both anode and cathode catalysts. A major problem is the poisoning of Pt by COlike intermediate species (9,10). Recently, oxide-supported gold nanoparticles in the <10 nm size range have emerged as one of the best catalysts for CO oxidation (1-3,11), and for water gas shift reaction in reforming stage using 5 nm Au on Fe2O3 (6). Gold and its alloy with other metals in the nanosize range present new alternatives (2,12). Whether the unique properties of gold nanoparticles can be exploited for addressing these problems is a focus area of our work. The ability to harness the large surface area-to-volume ratios and the unique surface sites of nanoparticles in <10 nm size range, especially in heterogeneous catalysis, constitutes a major driving force in fundamental research and practical applications of nanoparticle catalysts. It is this size range over which the metal particles undergo a transition from atomic to metallic properties. The understanding of factors controlling the morphological and surface reconstitution associated with such a size range is of fundamental importance to the ultimate exploration of nanostructured catalysts. We have been investigating the interfacial structures and properties of core-shell types of nanoparticles consisting of gold or alloy nanocrystal cores and organic monolayer shells that were prepared by twophase synthesis (13) and processing (14) protocols. Important attributes of such nanoparticles include controllable size monodispersity, processibility, and stability towards size- and composition-tunable catalysis (15-21). Some of these attributes were studied for understanding their electrocatalytic properties in the oxidation of methanol and reduction of oxygen, which are of fundamental interest to fuel cell technology.

Oct 1, 2003

By Donald Carlisle

"IntroductionTHE OPINION is held by many persons outside the mining industry, and by some within it, that mine •operators customarily find it advantageous to mine •only the richer parts of orebodies and to leave behind, perhaps permanently, leaner material which could be mined only at a lesser profit. This opinion and the inference which might be drawn from it that 'gutting' of mineral resources is a common feruture• of the mining industry are prejudicial to the intertsts of the industry and deserve careful scrutiny. Oddly enough, a theory of mine economics which gives much support for the opinion was advanced first by members of the mining profession itself, has been repeated •several times in mining literature, and to my knowledge has never been adequately refoted.According to the theory, selective mining of the rich ore first on a large scale will yield substantial gains and these gains do not merely reflect the desire of 'money minded investors' for a quick return but derive from the logical application of compound interest rates and the concept of ;present value. W. O. Hotchkiss and R. D. Parks (1) illustrate the reasoning with a hypothetical example in which an orebody of 4,000,000 tons may be mined either in its entirety in forty years at $1.00 per ton profit or selectively with the recovery of only the richest half in twenty years at $1.50 per ton profit. They show that, with Hoskold rates of 4 and 8 per cent, the present value of profits from mining only the richer 2,000,000 tons exceeds the present value of profits :from mining the whole orebody by about 20 per cent."

Jan 1, 1953