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By B. K. Mishra, Avijit Biswal, B. C. Tripathy, Abhijeet Singh, K. Sanjay, T. Subbaiah

We studied theeffect of anode substrates such as pure lead (Pb), lead antimony (Pb-Sb), and lead-silver (Pb-Ag) on the structural and electrochemical properties of electrolytic manganese dioxide (EMD). X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and chemical analyses were used to determine the structural and chemical characteristics of the EMD samples. The charge-discharge profile was studied in 9 M KOH using a galvanostatic charge-discharge unit. In all the substrates the current efficiencies were more than 99% except with Pb-Sb where it was 90%. Results revealed the nature of the substrate strongly affected the morphology of the deposited material which in turn affected the electrochemical properties of the EMD samples. XRD analyses revealed that the nature of the anode did not affect the crystal structure of the deposited EMD and all the samples were predominantly ?-MnO2, which is electrochemically active for energy storage applications. The EMD deposited on lead substrate showed superior discharge capacity of 245 mAhg-1 when compared with other substrates.

Jan 1, 2014

By L. Frost

Physical Conditions Great Britain The physical conditions in the mines investigated in Great Britain are similar to those found in the mines of the Dominion Steel and Coal Corporation, with the important difference that many of the coal seams visited were interspersed by a large number of heavy faults, making the development of a continuous face operation difficult, and in many cases the life of a unit development was exceptionally short, adding to unit cost; but in spite of these difficulties, a great deal has been accomplished in the application of mechanical loading units in a number of the mines in the areas visited. The coal-bearing measures, as in Nova Scotia, consist of shales and sandstones, and in some sections mussel bands overlie the coal seams making roof conditions difficult'. In several mines, the main roof consisted of weak shale bind, being held by a coal roof of varying thickness. This shale bind had a tendency to flow when the coal roof was broken. The floor, in some cases where cutter loaders were operated successfully, consisted of weak, flaky shales with very little resistance and a tendency to disintegrate into powder when broken. The depth of cover under which these mines were operating varied from 250 feet to 2,340 feet, with an average of 1,700 feet. The coal seams varied in height from 3 feet to 8 feet 6 inches, and the gradients from level to 33 per cent. The seams vary in hardness, but all-with the exception of one seam, the 'Morrison Busty'- presented a cutting problem similar to that found in Nova Scotia. The structure and cleavage of the coal was well defined and uniform. Some of the seams visited were gassy, ?but the temperature of the workings generally was not in excess of 70°F.

Jan 1, 1948

By J. A. Chamberlain

DURING a recent trip across Canada and parts of the northern United States, the. writer examined some forty mine models. Construction -details and the uses to which the models were being put were outlined in a report to Eldorado Mining and Refining, Limited, and a specific model was proposed on the basis of the Company's particular needs at their Beaverlodge operation. It was felt, however, that portions of the report would be of some value to anyone contemplating building a mine model. For this reason, a synopsis of some of the more important aspects of the problem is presented here, together with a suggested model type that appears to have wide application. Thanks are due not only to Eldorado for permission to publish the following material, but also to the many mine personnel across Canada who allowed the writer to examine their models and gave freely of their time in discussion.

Jan 1, 1958

By Y. Tanaka, M. Maeda, S. Suzuki, C. Tokoro, T. Kato, K. Muto

Boron (B) co-precipitation was investigated with ettringite to establish a cost efficient method of removing B from acid mine drainage. For 25 mg/L of B solution, most appropriate pH for B removal was pH 11.5. The most appropriate amount of reagent for B removal within Japanese effluent standard (10 mg/L) was B:Al:Ca:SO4 = 1:3:9:4.5, which corresponds to the composition of Ettringite (Al:Ca:SO4 = 2:6:3). The effect of silicate, carbonate and temperature on efficiency of B removal is important as groundwater and hot spring water are often contaminated. When silicate and carbonate are present, more Al and Ca salts are needed for B removal since some aluminum and calcium precipitate with silicate and carbonate as kaolinite and calcium carbonate. These precipitates do not contribute much to B removal. As the temperature raised, the most appropriate pH for B removal decreased. B removal became less efficient as monosulfate precipitated more rapidly as ettringite.

Jan 1, 2015

By R. L. Brown

The burning sulphide ores in the Sullivan Mine generate sulphur dioxide gases. This paper is concerned with a description of the environmental impact of SO2 on air quality in the mine and on the surface in the vicinity of the mine. As a result of surface caving, SO2 has been able to vent to surface and winds have carried it into one residential area of Kimberley. Monitoring practices are described.

Jan 1, 1977

By Norman B. Davis

THE ceramic group of industries is comprised of those engaged in the manufacture of cement, glass, artificial abrasives, whiteware, including earthenware, stoneware, porcelain tableware, porcelain sanitary ware, electrical porcelain, floor and wall tile, porcelain enamel on metals, refractories of all kinds, sewer-pipe and structural clay products, such as terra cotta, brick, and hollow tile. The various sub-divisions of the industry produce a wide range of articles on which we depend for our creature comforts from day to day, perhaps to a greater extent than we generally realize. The industry, in turn, depends on a great number of minerals, and chemical products derived from minerals, and it is the object of this brief paper to present a list of these with notes indicating the particular applications. In order to bring home the importance of the industry to your daily life, stop and consider the many things around you accepted as a matter of course. Cement provides the smooth surfaces of many of our highways, city streets, and sidewalks. It enters into nearly all types of construction, alone or in combination with other clay products. Glass we hardly appreciate because we can see through it so easily, but it is there to serve us in windows, doors, and other light-transmitting structures. Glass is the universal means of transporting liquids and beverages, our beverages are usually served in it, and, with the recent development in fine spun glass textiles, there is a possibility of glass clothing in the future. Chinaware, a general term for table dishes, may be earthenware (not vitrified), semi-porcelain, or bone china, but it is before us three or more times a day ?and we seldom think of the minerals that have made these products possible. Floor tile, wall tile, and other ceramic specialties for interior and exterior use and decoration please the eye and provide sanitary surroundings.

Jan 1, 1938

By Young Hyun Paik, Hyung Sup Choi, Yeun Sik Kim

The basic studies on the surface properties and flotation characteristics of ilmenite were made by electrophoretic, adsorption, contact-angle and floatability measurements. The isoelectric point of ilmenite is found to be at pH 5.6. By combining the results of electrokinetic studies and adsorption measurements, a clearer picture of the ilmenite-solution interface was observed. These findings were correlated with the floatability of ilmenite obtained by Hallimond tube tests. The general flotation characteristics of ilmenite are compared with those obtained for magnetite and rutile. It is indicated that the above three minerals, namely, ilmenite, magnetite and rutile, have very similar surface properties and flotation characteristics. Therefore, it is difficult to make an effective separation of these minerals by flotation. However, it is found that sodium orthophosphate acts as a selective depressant for magnetite in anionic flotation. Therefore, close pH control of the pulp in the presence of the phosphate ion enhances the possibility for a successful separation of these minerals.

Jan 1, 1967

By Deepak Bhadouriya, Saurabh Singh, Aditya Raj Suman

"An experimental study of chemically enhanced filtration and dewatering of fine coal slurry with and without additives was carried out. The experiment involved determination of effect of slurry concentration, additives (cationic, anionic and nonionic), filter area, filtration velocity, particle size and cake resistance on dewatering and filtration using vacuum filtration cell. Finally, the rate of filtration and dewatering and optimum amount of additives used were determined under suitable filtration condition. Overall, it was found that the filtration and dewatering characteristics were enhanced by increased slurry concentration, larger filter area and larger particle size. In addition of additives, the kerosene was found to be best for enhancing the filtration which yielded cake moisture reductions of approximately 17% by weight. At optimum dosages, the final cake moisture contents were reduced by 3.6% and 5.8% by weight using the appropriate surfactant and flocculent, respectively.INTRODUCTIONFor India, it is estimated that coal constitute a principal source of energy for the next several decades. It is majorly used at thermal power plants to generate electricity and also to a great extent in steel and cement industry. It has been observed that its consumption is increasing so as to meet the energy requirements of the country. It has been found that in a coal preparation plant; approximately 20-25 percent coal is of the mined coal of the range below minus 0.5 mm (28 meshes). Generally, this fine fraction is discarded due to its high cost of processing and further utilisatisation is very minimal. But with ongoing research and development for advanced clean coal technology, various new techniques have been evolved to maximize the utilization of available coal. In recent time technologies such as column flotation, cleaning of fine size coal to lower the ash content and low pyretic sulfur is feasible at high recovery value. But in various researches it is found that one of the biggest hurdles in utilization of fine coal cleaning technology by the coal industry is the economic dewatering of the fine clean coal product. Thus, until an economical and practical solution to dewatering of fine clean coal is achieved, the efforts devoted to developing fine clean coal technology will be wasted. In this paper an effort toward enhancing and developing the optimum technique of dewatering and filtration of fine coal slurry has been made."

Jan 1, 2016

By K. J. Boser

"Medium Voltage (MV) metal clad switchgear is referred to as the voltage class from 2.4 kV to 38 kV. Technological advances in circuit breaker designs over the last 20 years have given rise to retrofit options in lieu of complete replacement for older outdated circuit breaker technology. This paper examines the four MV breaking techniques that exist in industry and investigates various retrofit versus refurbish options for switchgear modernization and life extension. IntroductionThe life extension and upgrade of medium voltage circuit breakers is becoming an increasingly important issue in today’s modern industrial facilities from both a reliability and safety standpoint. Unscheduled downtime, loss of production, and plant safety issues are just some of the concerns that need to be addressed with aging switchgear. A thorough examination of the available breaking mediums allows an informed decision to be made when the time comes to assess equipment performance. If you look back over the history of medium voltage breakers, you will find that there have been four breaking techniques developed and widely used:• air magnetic;• minimum oil;• vacuum; and• SF6.Many facilities that were constructed 25 to 30 years ago relied on air magnetic or minimum oil circuit breakers in their distribution systems. At the time, these were the only “tried and tested” options and they afforded good service. Since then, however, newer technology has given us the vacuum and SF6 mediums which have both proven their reliability and monopolized the market. All the methods have their particular place in industry and what follows is a summary of the advantages, disadvantages, and chronological development of each breaking technique."

Jan 1, 1998

By H. J. White

The effect of alloying elements on the mechanical properties and weldability of wrought gamma prime strengthened nickel- base superalloys is well known. An understanding of the basic guidelines concerning alloying additions has led to the invention and development of HAYNES® 282® alloy for applications in aircraft and land base gas turbines and other high-performance high-temperature environments. The alloy combines exceptional high temperature properties with good weldability and fabricability. At high temperatures (~ 900 °C), the alloy is stronger in creep strength than Waspaloy alloy (UNS N07001) and it approaches the creep strength of R-41 alloy (UNS N07041). Because the alloy has better thermal stability, fabricability, and weldability than Waspaloy and R-41 alloys, it is currently being considered as a candidate universal consumable for welding/ repair welding of gamma prime strengthened nickel based superalloys and it is also being considered as a suitable replacement for applications where R- 41, Waspaloy, and 263 (UNS N07263) alloys are currently being used. The alloy was designed to have improved resistance to strain age cracking, a problem common to gamma prime strengthened nickel based superalloys. In this paper, we present (1) results from hot ductility testing of annealed and annealed/aged material; (2) results from Time Resolved X-ray Diffraction (TRXRD) studies during a welding thermal cycle of annealed and annealed/aged material, and (3) gas metal arc (GMA) and gas tungsten arc (GTA) welding of annealed and annealed/aged material.

Jan 1, 2010

By Michael Moser, Brighty Dutta, David Dreisinger

"Molybdenum is widely used in the industries as an alloying element in the manufacture of steels and super alloys. The widespread use of the element encourages a growing need to develop extraction processes for recovery from both primary and secondary sources. The Solvay Group has developed a solvent extraction reagent named CYANEX®600 for the recovery of molybdenum from acidic solutions originating from both low grade (e.g. copper solvent extraction raffinates, smelter dusts and slags) and high grade (molybdenite) molybdenum sources. CYANEX®600 is a purified form of CYANEX®272 with the active component bis(2,4,4- trimethylpentyl)phosphinic acid. The extraction behavior of CYANEX®600 towards molybdenum in sulphuric acid medium was evaluated. The uptake of molybdenum increased with the increase in concentration of CYANEX®600. The approximate stoichiometry of the extracted complex was: Mo: CYANEX®600 = 1:2. Efficient back-extraction could be achieved with 0.1 M disodium EDTA and 0.1 M (NH4)2CO3, thus providing the option of recyclability of the extractant. The detailed back-extraction studies are currently under progress to find out the possible option for complete transfer of Mo(VI) to the aqueous phase so that high purity Mo salts could be precipitated from the molybdate solutions.INTRODUCTION Molybdenum (Mo) is one of the world’s valuable metals and is highly sought after by researchers due to its versatile mechanical, thermal, chemical properties. Swedish scientist Carl Wilhelm Scheele demonstrated molybdenite to be a mineral sulfide in 1778. Peter Hjelm successfully isolated dark metal powder from the mineral sulphide and named it as ‘Molybdenum’ in 1782 (Gupta, 1992). Molybdenum is a refractory metal of silver gray appearance and is an important alloying element used in the manufacture of steels and super alloys. Molybdenum compounds are widely used in formulation of catalysts (Gupta, 1992). Molybdenum occurs in nature only in chemical combination with other elements. Several molybdenum bearing minerals have been identified, but the only one of commercial significance is molybdenite (MoS2). As molybdenum is a strategic metal for the industrial sector, its widespread use acts as a factor for depletion of the natural resources. Hence, there is growing need to develop extraction procedures for its recovery from both primary and secondary sources. United States, China, Chile, Canada, Peru, and Mexico are listed as the main producers by the U.S. Geological Survey, 2016 (U.S. Geological Survey, Mineral Commodity Summaries, January 2016)."

Jan 1, 2017

By R. C. Wallace

It was to be expected that the convening of the first Empire Mining Congress in June, 1924 in the city of London would turn men's thoughts very definitely to the question of exploring the mineral resources within the British Empire, the examining of her strength and her weakness in mineral material, and the consideration of steps that might advisedly be taken to strengthen her trade in minerals. That expectation was in part realized, though in the British way of presenting the case, and permitting the inferences to be drawn by implication. The opening address by the President of the Congress, to whom the Empire meant so much, gave a résumé of the contributions to the mining industry which were being made by the constituent parts of the Empire. The papers from the Institutes in Australasia, South Africa and Canada provided the details of resources and practice: while the individual contributions to the proceedings dealt with those phases of the mineral industry which are fundamental to the economic strength of British people, or to the health and well-being of the workers. While the subject matter thus presented was British mineral resources, and while the first consideration was the co-ordination and co-operation of British enterprise throughout the world, there emerged very clearly the wider viewpoint that the discussions had to do with a world industry, and with the contributions that that industry was making, and could further make, to the advancement of civilization irrespective of national boundaries, the world over. The invitations to representatives of the mining industry from the United States to participate in the Congress, and the warmth of approval which that participation evoked, were indications that such a congress cannot to-day be merely national in scope, and that trade in minerals, as in other natural resources, cannot be confined within national boundaries, but will seek its channels, unless artificial obstructions are too great, where the natural channels already exist.

Jan 1, 1925

By I. A. Menshikh, S. A. Kotov, N. L. Shinkarkin

All the cycle for conversion of natural and reprocessed uranium of ROSATOM’s “TVEL” Fuel Company is concentrated at the Siberian Chemical Plant. Conversion capacities are located on two sites, i.e. the Radiochemical Plant, which refines feedstock, and the Conversion Plant, which produces uranium oxides and uranium hexafluoride. Liquid radioactive waste arising in the process, after pretreatment, is transferred to a dedicated national operator for underground disposal. Environmental strategies pursued by the Fuel Company involve the introduction of process solutions intended to eliminate liquid radioactive waste and convert it into a solid phase. In the 5–7 years coming, work will be performed to refurbish and upgrade conversion facilities of the Siberian Chemical Plant that will principally change its radioactive waste management scheme. This paper describes the current waste management scheme and sets out planned schemes for management of natural and reprocessed uranium waste, which will be implemented in the refurbishment of conversion facilities of the Siberian Chemical Plant. The new technologies for the management of liquid radioactive waste from uranium conversion described in the present paper have an undeniable advantage over the current technology mainly due to significantly less environmental harm.

Jan 1, 2020

By Mike Broczkowski, Laura Dewhirst, Kieran Large, Angelo R. Fernando, Heather Daigneault, Jim Johnson, Randy Wiens

The radioactive isotope radium 226 is a contaminant of potential concern in effluent waters from metal mining operations in Canada. Acceptable release levels of radium 226 are governed by Metal and Diamond Mining Effluent Regulations. Since radium is invariably present as a companion element in uranium ore, monitoring and controlling of radium 226 is a must for uranium mining operations. Measurement of radium 226 is traditionally carried out through a radiochemical technique involving selective co-precipitation of radium with barium sulphate followed by alpha spectroscopy for quantification. As of 2010, Cameco has also been using an ICP-MS based radium analysis method developed in collaboration with a research team at Trent University, Peterborough, Ontario. This method, which is highly automated and requires significantly less sample handling, with improved turn-around-times, is being used by Cameco site laboratories at the McArthur River and Cigar Lake mines as well as the Port Hope Conversion Facility. This paper compares the benefits and drawbacks of this new method, compared to the traditional alpha counting procedure drawing from almost ten years of field experience.

Jan 1, 2020

By Gerry Roblesky

"IntroductionWestar Mining Ltd. is Canada's largest producer of metallurgical coal for the export market. It currently operates two mines, the Balmer Mine at Sparwood, British Columbia producing 6 000 000 tonnes per year and the Greenhills operation at Elkford, producing 2 100000 tonnes per year. Approximately 1600 people are employed between the two mines which operate independently but share common administrative services.Like most mining companies in Canada over the past three or four years, Westar has faced rising production costs along with flat or declining prices and demand for its products. In order to survive under these conditions it has become necessary to strive for decreased costs in any way possible. Over the past two years there has been a widespread introduction of microcomputers across the company. In order to satisfy increasing demand for accurate and pertinent information while at the same time increasing productivity, the microcomputer has become an invaluable tool.This paper describes some of the problems faced by a mine maintenance department in this operating climate and how they were solved with the help of a microcomputer. It also describes some of the problems that may be encountered both with equipment and people and recommends some ways that these might be minimized or avoided. Finally, an assessment of whether or not the move to microcomputers was a current and economical one, and a brief description of future plans and projects is given.The Maintenance OrganizationIn order to appreciate fully the role that microcomputers are playing within the Maintenance Department at Westar Mining, a little background on the organization and operating philosophies is in order. Most of the comments apply directly to the Balmer operations, however, the Greenhills operation is similar in concept.The mine maintenance organization operates on a fleet based concept with these departments reporting to the maintenance superintendent: haulage trucks, shovels and drills, loaders and Caterpillar equipment, maintenance services, and rebuild services.Each of these departments is headed by an assistant superintendent and is responsible for all maintenance on the equipment on the respective fleet. Shift foreman, planners, specialists and clerical staff are assigned to each fleet. A central engineering and administrative group consisting of one engineer and three clerical positions is responsible for maintenance engineering and centralized administrative services"

Jan 1, 1988

By Barry D. Simmons

Abstract -A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-1990s and the company is confident that this target will be achieved.

Jan 1, 1992

By L. I. Kiss, S. Perron, S. Poncsák, A. Perron

Aluminium industry has an increasing interest in the diminution of the energy consumption of the Hall-Heroult process by the reduction of the anode bottom covering with gas. Electrically isolating carbon-dioxide bubbles, produced at the anode, increase the ohmic resistance of the cell. As the gas production rate is determined by the applied current density, anode covering can be decreased only by a faster evacuation of the gas from the inter-electrode space. Among others, the inclination and curvature of the anode bottom promotes the release of the bubbles and thus decreases the mean value of the covering. Indeed, anode, insert in the molten cryolite bath has a square shape with horizontal bottom. However, inhomogeneous anode consumption, electro-erosion, bath circulation and the inclination of the bath-metal interface modify this shape gradually during electrolysis. Anode bottoms become inclined with rounded comers. This concentrates the gas generation to the center zone of the anode. As the bubble layer cannot be observed directly because of the hostile environment and the opacity of the bath, real scale air-water systems are used to study the impact of the anode geometry on the anode covering and the bubble induced flow. However, the physical properties of such a system are different than that we can found in the real cells. A simulator using the Lagrangian description of the bubble layer has been built and presented in earlier papers. This tool was used to investigate the effect of the anode inclination on gas covering and bath velocity, for both C02-cryolite and air-water system. Results obtained for the second system were compared to experimental data .

Jan 1, 2006

By Erik Q. Dahl

The strength of green and sintered pellets during reduction under various conditions in a laboratory kiln has been investigated. Equipment and test methods are described, together with the results obtained. The strength of sintered pellets drops sharply when the reduction starts, and goes through a minimum at the 70 per cent oxidation level. At more advanced reduction, the strength increases with increasing metallization. Successful use of green pellets as kiln feed requires that more attention be paid to the pellet preparation than is necessary when producing pellets for separate sintering. In particular, the ores have to be ground to a greater fineness. The initial strength of green pellets is low. Below the 70 per cent oxidation level, however, the strength of these pellets is about the same as the strength of sintered ones. Additions of such materials as silica, limestone and anthracite coal; within reasonable limits, affect the strength only slightly.

Jan 1, 1966

By B. Tiryaki, M. Ayhan, O. Z. Hekimoglu

Coal shearers are one of the major sources of dust and fines in underground coal mines. Despite considerable research investigations, no comprehensive in situ investigations coupled with extensive laboratory studies on the effects of drum design on generation of dust and fines have been found. It may be for this reason that many major shearer drum manufacturers persistently employ a certain drum-lacing pattern on current coal shearers, which is believed to cause excessive dust and fines in coal mines. This paper shows how respirable dust and fines are minimized under near-identical conditions when the drum lacing pattern was changed from a triple-tracking to a single tracking arrangement. A series of laboratory trials simulating in full scale the practical cutting action of tools was followed by extensive long-term underground trials during production operations in OAL (Cayirhan) Lignite mine in Turkey. The results are presented and discussed, and recommendations for proper drum-lacing in terms of respirable dust and fines are made.

Jan 1, 2002

By E. L. Jones

THE concentration of tin in the tailing from Sullivan ore has been de-scribed by H. R. Banks, superintendent of the Sullivan concentrator, in a paper presented at the annual meeting of the B.C. Division of the Institute in October, 1941(1). The reduction of the concentrate EARLY EXPERIMENTAL WORK Experimental work on the smelting of Sullivan tin concentrate was done in Trail. Preliminary tests in the laboratory indicated that the concentrate could be successfully treated in an electric furnace. A small electro-thermic pilot plant was built and, at the same time, reduction tests were made in an oil-fired reverberatory furnace. Both types of treatment gave satisfactory results. It developed that no fluxes, other than those already in the ore and in the ash of the reducing agent (either coke or coal), were needed. By using an excess of iron, a complete recovery of the tin in the slag was obtained, but with 20 to 30 per cent iron in the tin. A counter-current treatment was thus indicated, viz., the primary slag was first treated with hard-head (iron-tin alloy) from the refining and final slag smelting, producing tin with 2 to 4 per cent Fe. This secondary slag was subsequently treated with scrap iron to produce tin-iron alloy, and a final slag low enough in tin to waste. By following this line of endeavour, a tentative flow-sheet was drawn up and a successful operation was established. Without resorting to electrolytic refining, a metal comparable in purity to standard tin was produced. Metallurgical results and operating costs were found to be very similar with an electric furnace or a fuel-fired furnace. 'However, electric furnace smelting was chosen because the furnace required was smaller, and because some doubt existed as to the cleaning of the final slag in the reverberatory furnace reduction.

Jan 1, 1944