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By Frands Jensen, Erik Eriksson

"Haldor Topsoe’s Wet gas Sulfuric Acid (WSA) technology has been proven in a number of industries converting sulfurous gasses to concentrated sulfuric acid. In the metallurgical sector plants have been delivered handling SO2 gasses from copper, zinc, molybdenum, and lead ore. WSA has high energy efficiency and allows autothermal operation from feed gas strengths as low as 3.0% (volume). Recent variants of the WSA process have been developed that allow very high SO2 conversion efficiencies of over 99.9%. This paper describes the technology, its advantages and industrial achievements.The WSA technology is well suited for production of concentrated sulfuric acid of commercial quality from the sulfur dioxide (SO2) gas that inevitably emerges from the metallurgical processes. Some of the features that make the WSA technology attractive for this application are:- High SO2 conversion rates (up to 99.99%)- High energy efficiency leading to a low autothermal point (~ 3% SO2)- No need for gas cooling and drying to produce concentrated sulfuric acid- No production of waste- Very low cooling water consumptionThis paper describes the WSA process principles and highlights features that make this process attractive for handling SO2 gases."

Jan 1, 2014

By Ronald G. Hamm

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

Jan 1, 1983

By L. M. Cumming

"The contact between dolomite of the St. George formation (Cambro-Ordovician) and limestone of the overlying Table Head formation (Middle Ordovician) is a regional disconformity. This is best illustrated from exposures on Pointe Riche Peninsula, near Table Point, and along Port au Port Bay. The contact occurs along 180 miles of the west coast of Newfoundland from St. John Island in the north to the western part of Port au Port Peninsula in the south. A disconformity of the same age occurs between the Romaine and Mingan formations on the north side of the Gulf of St. Lawrence.Dolomitic beds beneath the disconformity locally contain concentrations of base-metal sulphides. Sphalerite occurs in dolomite pseudobreccias of the St. George formation at Zinc Lake, 7 miles northeast of Daniels Harbour. The 'Western Newfoundland Lower-Middle Ordovician regional disconformity is interpreted as having originated on and near the edge of a broad platform, and to have provided an important regional geological control in the localization of zinc mineralization."

Jan 1, 1968

By A. C. Ter-Oganesyants, N. N. Anisimova, G. P. Kotukhova, G. N. Dylko

The process utilized at Norilsk Nickel Polar Circle Division for treating slimes from the electrorefining of copper and nickel was developed in the late nineteen fifties and has survived without any fundamental changes. This technology is a combination of pyro and hydrometallurgical operations to produce PGM concentrates that are sent away for refining. The characteristic feature of the current technology is multiple-stage, extended cycle treatment with significant incomplete production, low labour and automation efficiency and poor hygiene and sanitary conditions. To eliminate all negative aspects mentioned above, specialists of Norilsk Nickel Polar Circle Division have developed a new hydrometallurgical process for treating electrolytic slimes. The main steps of the flow sheet developed are autoclave leaching of the slimes and electrochemical opening-up of a cake from autoclave leaching. The implementation of the new process will allow Norilsk Nickel Polar Circle Division to shorten the process cycle 4-5-fold thus reducing the volume of incomplete production, considerably increase labour efficiency, simultaneously improving working conditions, upgrade the final concentrate, reducing costs and increasing PGM recovery during refining and, ensure higher security of precious metals by employing automated processes and vacuum sealed units.

Jan 1, 2004

By James D. Bliss, David M. Sutphin

"On the basis of differences derived from genetic, descriptive, and grade-tonnage data, graphite deposits are classified here into three deposit types: disseminated flake, amorphous (microcrystalline), or graphite veins. Descriptive models have been constructed for each of these deposit types, and grade-tonnage models are constructed for disseminated flake and amorphous deposit types. Grade and tonnage data are used also to construct grade-tonnage models that assist in predicting the size and grade of undiscovered graphite deposits. The median tonnage and carbon grade of disseminated flake deposits are 240 000 tonnes and 9% carbon and for amorphous deposits, 130 000 tonnes and 40% carbon. The differences in grade between disseminated flake and amorphous deposit types are statistically significant, whereas the differences in amount of contained carbon are not .IntroductionIndustrial minerals, including mineral construction materials such as sand, gravel, and crushed stone, have historically exceeded metals in global production value. Today, industrial minerals are being used in new and sophisticated ways in response to the late 1980s emerging information- and service-based economies' requirements for less metal and more industrial minerals . Natural graphite is an example of one such mine ral that has been known since ancient times, and is now finding new applications. Graphite was first used as an industrial mineral in Bavaria in 1400 A.D. where it was an important component of crucibles. Traditionally, natural graphite has been used in heavy industries. New applications, such as development of carbon-magnesite bricks a decade ago and the current advancement of alumina/graphite refractories, are increasing its graphite use. Other new uses for natural graphite, such as the use of graphite powder as a thermal blanket for the continuous casting o f steel (Northern Miner, 1987) and the addition of expanded graphite to polyurethane foam where it acts as a flame retardant (Industrial Minerals, 1987), are increasing the demand for this mineral. To meet future demand for graphite and other industrial minerals, knowledge of the characteristics of the deposit types in which they are found is important. A further look at the deposit types for graphite and at construction of descriptive and grade-tonnage models is warranted .The graphite industry recognizes three basic types of graphite , distinguished primarily on the basis of grain size: crystalline flake, lump and chip, and amorphous. These naturally occurring forms of graphite are products of metamorphism and are found in schists of various types, gneisses, and marbles. Temperatures of at [east 400°C are thought to be required for graphite formation (Landis, 1971). Synthetic graphite, also known as artificial or manufactured graphite, is a man-made carbon product and offers higher purity and lower crystallinity than natural graphite. Several authors have written about graphite's unique physical and chemical properties and the uses for individual types of graphite (Krauss et 01., 1988; Graffin, 1983; and Harben and Bate s, 1984)."

Jan 1, 1990

By M. E. Moraes Castanho de Almeida, A. Ribeiro Cotri

Recovery of cobalt to produce high grade cobalt sulfate from cobalt concentrate by leaching and solvent extraction was investigated. The PLS typically contains Co 10g/l, Mg 2g/l, Fe < 10ppm, Mn < 200ppm, insolubles <100ppm and is extracted with 20wt% Cyanex??272. The typical strip solution contains Co 60g/l, Mg 0.03g/l, and was sent to the current process for the production of cobalt sulfate heptahydrate. The cobalt yield of the plant with two extraction steps was 92%, with three steps was 97% and with four steps 99%. The extraction stage used the concept of "scrubbing" in a countercurrent system. In the first stage of extraction pH was 4.8, and in the last stage of extraction pH 5.5 to promote the exchange of magnesium in the organic with cobalt contained in the PLS. Following the extraction, when using two scrubbing stages, Co/Mg selectivity between of 2,000-3,000 was obtained, and with three scrubbing stages, selectivity was greater than 6,000. The desired selectivity was reached when using a scrubbing configuration with O/A ratio of 10:1. The typical cobalt sulfate heptahydrate had the following composition: Co 20wt%, Mg < 0.01wt%, Fe < 5ppm, Mn < 0.01wt%, Cu < 0.01wt%, Zn < 0.01wt%.

Jan 1, 2014

By Michel Ruel, Ali Soltanzadeh, Benjamin Légaré

High fidelity commercial process simulation packages can be used at different stages of a greenfield project, from initial plant design to operator training in the later stages. However, there are several factors that make the software less attractive for small and medium size brownfield projects, such as the licensing cost and the fact-finding manpower required for model design and simulator maintenance. In this paper a different approach is described. The knowledge gathered from operating personnel was used to implement higher level models based on plant data, operating heuristics, and experience rather than detailed component-level models. The computing platform used was a low-cost, well-established, control system vendor-independent software. Throughout this paper we demonstrate the success of implementing this model-based approach using two industrial examples. The first example is a simulation of the carbon monoxide (CO) distribution system at a metallurgical complex. The purpose of this simulator was to test new control strategies and PLC programs prior to implementation. CO being a toxic combustible gas, validation of the suggested control system changes was necessary for plant safety. Simulation of specific operating conditions helped alleviate concerns and improved plant-wide acceptability of the new operating philosophy. The second example is a boiler simulator at a petrochemical plant. The operator training simulator (OTS) was designed as a platform for experienced operators to practice handling rare or abnormal conditions. A customized medium-fidelity model was developed for this targeted application where the cost of a full scale high-fidelity model could not be justified.

Jan 1, 2016

By Laura Kelsey

Contaminant Robust In Situ Water Extractor CRIWE Nafion-based water clean-up Extract purified water from natural extraterrestrial sources In situ water processing for downstream electrolysis Chemically resistant to process contaminants such as acid

May 1, 2013

By A. A. Ruitenberg, C. J. Morrissy

"The Lake George antimony deposit comprises a system of stibnite-bearing quartz veins that cut Silurian greywacke and slate. The stibnite-bearing ore zone is in part enveloped by a uraniferous zone.The ore-bearing quartz vein system occupies an easterly striking, gently north-dipping fracture system that cuts across north-northeasterly trending gently southwest-plunging, tight Acadian (early Middle Devonian) folds. This vein system continues at depth into a siliceous skarn zone intruded by altered granite porphyry dykes, which constitute probably a late phase of the Hawkshaw granitoid intrusion to the north.Most of the ore occurs in a northeast-plunging, trough shaped vein structure that formed where the vein system (gently north-dipping) intersects the axial surf ace zone (steeply northwest-dipping) of an Acadian synform. The trough shaped structure resulted from deflection of the fracture zone (containing the vein system) by competent beds.Emplacement of the quartz-stibnite veins was preceded by, and is in part penecontemporaneous with, the formation ofa micaceous-argillaceous alteration halo, which in turn intersects a patchy biotite alteration zone.The hypabyssal intrusions associated with the Lake George deposit probably represent a late phase (early Carboniferousr) of the nearby Hawkshaw intrusive granitoid complex. IntroductionThe Lake George Antimony Mine is situated 40 km southwest of Fredericton and 2.5 kin north of Lake George, New Brunswick (Fig. 1). The mine is owned by Consolidated Durham Mines and Resources Ltd.Shaw (1940) described the early history and development of the mine. In subsequent years, available drill cores were relogged by several geologists. Much new information became available when an extensive diamond drilling program (Kidd , 1970) was started by Consolidated Durham Mines and Resources Ltd. in 1970. A study of the geology and economic potential of the deposit was made by Glover (1973). Abbott and Watson (1975) made a study of the ore mineralogy. Available drill cores were relogged and a preliminary study of the fracture system in the mine was made by G.A. Pierce and A.A. Ruitenberg during 1976. Outcrops in the area sur rounding the mine are extremely sparse.Between 1976 and 1979 the present authors made a detailed study of the mine workings, available drill core and regional structure in the vicinity of the mine, with results set forth in this paper. The regional geologic setting of the deposit, the geometry and structural controls of the ore zones, and the mineral zonation and rock alteration are emphasized."

Jan 1, 1980

By Masatsugu Morimitsu

This paper introduces new technology of oxygen evolution anodes which can be applied to produce copper, zinc, cobalt, and other metals by electrowinning. The anode consists of nano iridium oxide particles dispersed in amorphous tantalum oxide matrix as a catalytic layer formed on a titanium substrate. The anode can reduce oxygen evolution potential by 0.25 to 0.55 V compared to commercially available lead alloy anodes and can suppress unwanted side reactions such as manganese oxyhydroxide, lead oxide, cobalt oxyhydroxide which occur during oxygen evolution in the electrowinning solutions. This technology is effective for environmentally friendly electrowinning processes with low energy consumption and less anodic deposition.

Jan 1, 2011

By Douglas A. Sloan

"Recently, a number of major mining companies seemed unable to find a president from within the industry, and were searching outside the industry. From this, one could conclude that managers within the industry are either not being prepared or are not preparing themselves for presidential responsibility. Opinions were sought from a number of senior executives, to attempt to define the skills a prospective president should acquire and what actions a company could take or that a prospective president could take to acquire these skills.This paper contains summaries of the opinions obtained, along with the author&apos;s comments. The paper also describes the actions some companies are taking and the actions that an aspiring president can take to prepare himself for corporate management.IntroductionA manager is promoted up the management ladder when the manager&apos;s superiors believe that he is capable of handling a more senior position. Normally, the manager acquires this credibility by outstanding performance in his current management post, whether it be in a junior management (supervisory) or in a vice-presidential capacity.In most instances, the skills required for promotion can be acquired in the current position or, at worst, the abilities exhibited in a candidate&apos;s current role will convince his superiors that the necessary expertise for the more senior position can be acquired on-the-job. This is particularly the case when the new skills are felt to be an extrapolation of the old skills.However, in the case of appointment to presidential rank, there appears to be a need for new expertise which often is not acquired in normal management progression or, at least, boards of directors of some mining companies seem to believe this to be the case. The objective of this paper is to attempt to define the new skills that should be acquired by a manager who aspires to be the president, and to describe what actions might be taken by him to acquire them."

Jan 1, 1982

By D. V. Krefting, D. R. Bennett

"The Cyprus Anvil Mining Corporation established a lead-zinc mine and concentrating plant at Faro in Yukon Territory in 1969. Following some 12 years of continuous operation from a single pit adjacent to the concentrator, the company decided to expand operations into two additional areas on the Vangorda Plateau. The two new deposits, known as Grum and Vangorda, are located some 15 kilometres from the existing concentrator.Confirmation of mining feasibility was followed by determination of the most practical and economical method of transporting the raw ore from the new mine sites to the existing concentrator. This analysis was carried out in two phases. The first phase reviewed the feasibility of alternative transportation systems on an &apos;order-of-magnitude&apos; cost basis. This work identified systems worthy of more detailed examination. The second phase examined the preferred alternatives in greater detail.Initially, operating principles and parameters were established and catalogued. Then, based on these criteria, complete systems were developed utilizing alternative modes of transportation . In the overview analysis, some transportation modes were judged impractical and discarded, &apos;order-o f-magnitude&apos; costs were developed for other systems and the most costly were eliminated . In the detailed study, the favourable systems were examined in depth which required development of accurate capital and operating costs, consideration of environ- mental impacts and an assessment of intangibles associated with the operation of a new development."

Jan 1, 1984

By T. G. Carter

"During the early part of the 1980s, four new surface coal mines commenced operation in the Province of British Columbia. Each represented a major investment in both persons and materials in order to protect this investment in one significant area-the fixed portion of the surface coal handling system-a substantial amount of work was undertaken to ensure that the system was well protected from an outbreak of fire. A great deal of effort in this field had already been made by those coal mines which had been in operation for a number of years and experience gained at these operations was utilized in determining the level and extent of fire protection for the new mines.This paper summarizes the major problems, and suggests some of the methods of solution, in providing an adequate degree of fire protection for surface coal handling systems. It will also discuss the potential for gas and dust explosions together with ways to minimize this potential.The Fixed Coal Handling SystemNote: The word ""fixed"" has been used in its present context to denote that part of the coal handling system where the coal is moved via fixed installations such as a conveyor. It differentiates from that part of the system where coal is moved by mobile equipment.The raw coal delivered to the truck dump will undergo two major processes on its way to the rail load out. The first will be at the coal preparation plant where coal of specified quality will be extracted from the raw feed to the plant. If this coal is of metallurgical quality, and sometimes if it is of thermal quality, it will pass through a thermal dryer where part of the moisture acquired during coal preparation will be removed, i.e. the second process. As the complexity of both the coal preparation plant and the thermal dryer is such as to warrant separate considerations they will not form part of this paper. Each of the processes, however, is generally, housed in its own building, thus, containment of any hazards is usually more attainable than those existing or caused in the rest of the system."

Jan 1, 1988

By D. Chakravarty, B. Samanta, D. Ghosh

Autonomous robots are useful for 3D underground mine mapping to avoid human exposure to hazardous spaces. To prepare a precise mine map, a self-navigating robot must navigate an arduous path, avoiding obstacles and sensing the environment. A prototype laboratory-scale robot was built and evaluated through a mock-up in a test mine gallery. It was outfitted with a 2D laser scanner, a stereo camera for obstacle avoidance, and a high-precision, laser-based imaging and digitizing system for collecting 3D point cloud data. Various algorithms were used for scan matching to facilitate simultaneous localization of the robot for mapping.

Jan 1, 2014

By Philip M. J. Gray

"The real cost of conversion from ore to semi-fabricated non-ferrous metals has been increasing for many years. Consumer resistance and improved knowledge and techniques now available justify investment in revolutionary as well as evolutionary methods of extraction. Metallurgical factors in current practice which preordain high production costs are identified as: smelters&apos; demand for clean minerals, use of processes with low intensity of working per unit of reactor volume, use of low-velocity reactions, use of long reactor retention times relative to the speed of reactions, dilution of values in solution and commitment to electric power as a source of energy.Six new types of flowsheet are proposed for processing from ore to metal, composed of steps which are economic to construct and maintain and making maximum direct use of fossil fuel and the energy content of minerals. The basic knowledge and technology for developing these flowsheets exists. It is very tentatively suggested that these routes might reduce the capital and production cost for conversion of ore to metal by 30-50%."

Jan 1, 1980

By Paul A. Glapa

Quality is much more than providing a product that functions properly. True quality is a way of thinking, a way of doing business, and, ultimately, a way of satisfying a customer?s long-term needs. A true commitment to quality requires a top-down management commitment, with a willingness to change what needs to be changed and to expand upon ?best practices? that are already done well. Is there a cost to creating and maintaining a quality program? Of course there is, but the cost of not having a focused program is much greater. We have come to regard quality as an investment that pays dividends to both the supplier and customer. The lack of quality costs everyone and the customer pays the ultimate penalty. With modern, highly engineered surface mining equipment the end user calculates cost in terms of lost production (revenue), not simply the cost of the part. Bucyrus International, Inc. is a company that has listened to its customers and has dedicated itself to implementing an advanced quality program. The ultimate goal being the creation of a high quality product with extended reliability for the customer. The result is reflected in Bucyrus? current product offerings and highlighted by the new 495HF electric rope shovels at Albian Sands mine.

May 1, 2003

By J. Baumbach, H. Bombach, M. Stelter

"Today technical electro-refining processes for copper exclusively use sulfuric acid, for silver refining nitric acid electrolytes are used. Sulfuric acid is characterized by very good chemical and electrochemical stability, good conductivity and low cost. The disadvantages of sulfuric acid are the precipitation of fine-grained cathodes with smooth surfaces only by using additives like glue, thiourea and chloride. In case of silver the electrolyte is electrochemical unstable and bears the risk of the formation of toxic NOx when pH is too low. A second disadvantage is the form of electrodeposition of silver as dendrites with their removal from the bottom of the Möbius cells.This paper reports the results concerning the application of an alternative electrolyte in copper and silver electro-refining. At first the electrolyte was characterized by the determination of current density potential curves. Electrolysis experiments were performed in laboratory scale using technical anodes for copper and synthetic anodes for silver. During the copper tests the solubility of contaminations from the anodes and the amount and chemical composition of the anode slimes were determined. Moreover the influence of current density, electrolyte temperature and the effect of several additives on the precipitation and chemical purity of the cathodes were investigated. In all experiments cell voltage as well as anodic and cathodic polarization was measured and current efficiency and specific energy consumption were calculated. A comparison with the results with those of tests using conventional sulfuric acid electrolyte shows the advantages and disadvantages of both systems, additionally the technical application chances and limitations for the new electrolyte. This electrolyte enables the precipitation of smooth copper cathodes with low silver and sulfur concentrations even at lower temperatures without any additive. For silver refining the electrodeposition of compact silver sheets is possible, that can be stripped comparable to those in copper electro-refining."

Jan 1, 2016

By Dale Coffin

Definition Of A Crisis Crisis \kri-ses:\ An unstable or crucial time or state of affairs whose outcome will make a decisive difference for better or worse (Webster&apos;s New Collegiate dictionary) An event or set of circumstances that could significantly affect a company?s ability to carry out its business, damage a company?s reputation and/or threatens the health, safety and well-being of employees, the community or the public at large You?re Having A Crisis When... . The emergency poses a significant threat to the public or employees . The emergency situation provokes government scrutiny . The company no longer has full control of the situation . The situation has created significant regional, national or international media interest . The corporation?s reputation may be damaged or there is a threat to the bottom line or share value

May 1, 2004

By D. G. Brophey, J. A. O’Neill

"High costs, both in terms of human resources and financial costs, have long been the end result of accidents involving vehicles which continue to occur too often throughout our industry.For example, radio remote control LHDs too often seriously injure their operators in underground operations. Costly efforts are required by mine owners to provide safety bays and platforms from which their operators can work safely. In open pit operations, large heavy haulers have too frequently backed over vehicles or turned into vehicles unfortunate enough to be situated in their large blind spots. These are just two examples of situations that have occurred again and again under similar circumstances.Meanwhile, electronic methods of detecting proximity to vehicles have continued to develop. The time has come for the industry to think “outside the box” to evaluate whether many of these new methods can solve these recurring problems.This note takes a look at various types of proximity detection technologies that are in use today in other industries, and discusses the various potential applications within our industry."

Jan 1, 1998

By Donald S. Cameron

By dispersing gold in high surface area form supported on metal oxides, its inert character can be transformed to make economical, effective catalysts. Gold has already been demonstrated in a number of fuel cell applications such as gas phase catalysts, electro-catalysts, and electrical connectors. In this paper, the various types of fuel cell systems are reviewed, and several opportunities for gold identified. Low temperature fuel cells, including alkaline and solid polymer electrolyte types rely on high surface area platinum group metal catalysts which are highly susceptible to poisoning by low concentrations of carbon monoxide in the fuel supply. Hydrogen is frequently obtained by steam reforming hydrocarbons, followed by the water gas shift (WGS) reaction. A promising initial use for supported gold catalysts is in catalysing this WGS reaction. Research has shown that gold supported on iron oxide (Au/a-Fe2O3 ) WGS catalysts are more active than the current commercial copper oxide / zinc oxide catalysts, and effective at temperatures as low as 120oC. Products from reformer/ water gas shift reactors can be further purified by removing traces of carbon monoxide. If a small proportion of oxygen is introduced into the fuel gas stream, carbon monoxide can be preferentially oxidized to carbon dioxide even in the presence of hydrogen. Gold nanoparticle catalysts on iron oxide support (Au/a-Fe2O3 ) have exhibited higher activity than commercially available platinum on alumina (Pt/?- Al2O3 ) preferential oxidation catalysts. The low temperature of this reaction may make it feasible to incorporate these catalysts within the fuel cell itself. Proton exchange fuel cells provide several possible applications for catalytically active gold and its alloys. Carbon supported platinum group metals would benefit greatly from improved electrical conductivity if gold replaced some or all of the carbon support material. As electrode current densities are raised, electrical resistance constitutes an increasing proportion of voltage losses within the fuel cell. Dramatic reductions in cell stack voltage losses have already been demonstrated by reducing inter-cell contact resistance using gold plating. The low temperature oxidation properties of gold catalysts have been investigated in controlling gaseous emissions from direct methanol fuel cells, and gold also provides essential catalysis in building direct borohydride oxidation fuel cells. The prospect of a range of other applications for gold in fuel cells to contribute useful improvements in corrosion resistance and conductivity is assessed. Globally, fuel cells have been developed for a wide range of applications including stationary generators, cars and buses, industrial vehicles and small portable power supplies, each of which represents a substantial market. Hence there are likely to be many and varied opportunities for gold catalysts to contribute to the performance and economics of the systems being commercialized.

Oct 1, 2003