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By C. Riveros, H. Henein

Bulk Metallic Glasses have a high potential as advanced engineering materials due to their various properties including strength and corrosion resistance, to name a few. This paper investigates amorphous phase formation and rapid solidification characteristics of impulse atomized Co-based alloys in order to understand and control the application properties of the final products. Amorphous fraction and kinetic crystallization properties of the atomized Co-based alloy powders were quantified by means of Differential Scanning Calorimetry. In addition, different but complementary characterization tools were used to analyze microstructures of the powders. These include optical microscopy, X-ray diffraction and micro-hardness tests. While the amorphous fraction within the powders is promoted by high cooling rate and smaller powder size as expected, hardness is found to decrease with the fraction of amorphous phase.

Jan 1, 2015

By F. C. Lendrum

Introduction The property of Normetal Mining Corporation is in Desmeloizes township, Quebec, twelve miles north of Dupuy on the main line of the Canadian National railway from Quebec city co Cochrane, Ontario. The ore bodies occur within a band of highly sheared and sericitized agglomerate which strikes N.60°W. and clips 82° north. Along a zone 1,000 feet or more in length and of variable width, the agglomerate has been replaced by copper, zinc, and iron sulphides, with copper usually predominant on the hanging-wall side and pyrite replaced in part by sphalerite on the footwall. A northsouth diabase dyke cuts through the ore zone near its east end. The Normetal mill produces a copper concentrate and a zinc concentrate which are shipped, respectively, to Noranda, Que., and Newcastle, Penn., U.S.A., for further treatment. The present paper deals with the milling of ore from what is known as No. 3 orebody. This is a lenticular body of high-zinc ore lying co the east of the diabase dyke, along the line of strike of the main ore zone, which extends westward from the dyke. On its northern side, No. 3 orebody is in contact along most of its length with a narrow band of copper ore which is highly oxidized.

Jan 1, 1948

By Wm Petruk

"The tungsten-bismuth-molybdenum deposit in southwestern New Brunswick occurs in greisenized and silicified tuffite * and feldspar porphyry in and adjacent to volcanic necks. The ore minerals occur as veins and veinlets and as disseminated grains in gangue. These minerals can be grouped into three assemblages. Assemblage 1 consists of oxides and phosphates of W, Ti, Fe, Nb, Sn, Ta and rare-earth elements, with the main minerals being deposited in the sequence wolframite, rutile, cassiterite. Assemblage 2 consists of arsenopyrite, molybdenite and bismuth, and assemblage 3 of sulphides with minor cassiterite and arsenopyrite. Sphalerite is the main sulphide mineral, but it contains minute inclusions of copper-tin- and indium-bearing minerals. Textural relations suggest that most of the elements can be recovered from this ore by conventional mineral beneficiation and extraction methods, but a variety of techniques must be employed. It is expected that the wolframite and molybdenite can be recovered satisfactorily, but poor recoveries are expected for bismuth and cassiterite. A sphalerite concentrate can be readily obtained by flotation, but it would contain a wide variety of elements. It is suggested that leaching be used to recover the bismuth and the elements in the sphalerite concentrate."

Jan 1, 1973

By F. W. Tregarthen

"This paper gives a brief description of the methods used to form and implement the present planned maintenance program. The system is designed to assist plant personnel in their task of controlling a large work-force and maintaining the many and varied types of equipment used in a mining and concentrator operation. The types of reports and methods used in scheduling and work-loading are described. General built-in flexibility is derived from computer assistance to the Central Planning Group."

Jan 1, 1971

By J. L. Jambor, R. W. Boyle

"The Magnet Cove barite-sulphide deposit is a raking pipe-like body that replaced and partly filled a large brecciated zone at the junction of two faults at the contact between sedimentary rocks of the Horton and Windsor Groups of Mississippian age. The principal minerals in the deposit are siderite, barite, hematite, pyrite, marcasite, galena, sphalerite, chalcopyrite, tennantite, proustite, pearceite, acanthite and stromeyerite. The mineral assemblage and textural relationships indicate that the minerals were deposited from low-temperature solutions. The source of the elements in the deposit is believed to be the enclosing sedimentary rocks, with connate or ground waters as the transporting medium, and solubility products as the governing factor controlling the abundance and order of deposition of the minerals."

Jan 1, 1966

By R. Farhat

Coating systems that yield a thermally grown oxide (TGO) protective layer have been proposed as a potential method for extending the lifecycle of components exposed to high temperature corrosion. This is particularly relevant to the petrochemical industry, where any reduction in corrosion rates can yield substantial cost reductions. The primary goal of this project is to develop a coating repair procedure and to investigate the oxidation performance of the repaired location. Electrospark deposition (ESD) was used to repair spalled segments of TGO grown on MCrA1Y substrates using various electrodes possessing mixed crystal structures. Specifically, electrodes of NiCoCrA1Y (BCC-FCC mixtures) and CoNiCrA1Y (FCCBCC mixtures), were deposited and oxidized to develop the TGO using a heat treatment of 24 hours at 1000°C in air. This presentation will focus on the microstructural evolution of the base metal and ESD repair on damaged area, in both as- deposited and oxidized forms. Results of SEM and XRD analysis will be presented.

Jan 1, 2011

By G. K. Quainoo

In the automotive industry, the awareness to meet Corporate Average Fuel Efficiency (CAFE) standards has evolved the need to reduce vehicular weight in new automobile designs, with the overall goal of reducing gas emissions into the atmosphere (Kyoto protocol), One efficient method has been to use lighter materials such as aluminum in outer body panels, Heat treatable AA6111 is one of the materials employed due to its unique combination of formability, paint bake strengthening and superior corrosion resistance characteristics, Researchers have applied various thermo-mechanical processes on 6000 series aluminum alloys and have found an improvement in the mechanical properties of these alloys, For a formed and painted automobile panel, the final mechanical properties involve a combination of strength components arising from cold work, strain aging and precipitation minus recovery. In this study, the evolution of microstructure resulting from the interaction of cold work and precipitation in AA6111 has been studied by means of transmission electron microscopy (TEM) after subjecting samples to various heat treatments, tensile testing and differential scanning calorimetry (DSC), This has been done to understand the evolution of microstructure and its influence on the properties of the alloy, The results show a considerable improvement in strength with a corresponding increase in strengthening precipitates with increasing level of cold work in the alloy. DSC results following the application of various levels of cold work also show acceleration in the precipitate phase formation, as precipitates are observed to form at lower temperatures, with increasing level of cold work/

Jan 1, 2005

By B. A. Zaharov, J. M. Shneerson, L. V. Chugaev, M. T. Zhunusov, A. M. Markelov, S. V. Drozdov

The main direction of research was the application of autoclave technology for the flotation concentrates or biooxidation feedstocks. The industry modernization also expects the possibility of increasing the yield of the flotation concentrate, to allow an increase in gold extraction in flotation circuit. This paper provides brief description of results obtained for concentrates with the yield of 4 and 8%, as well as corresponding biooxidation feedstocks. Technological efficiency of autoclave oxidation is shown for both concentrates and biooxidation feedstocks. The process has been evaluated on a laboratory and a continuous pilot plant scale. Gold extractions from POX discharge are ranging from 94-97% for each product, with only 5-7 kg/t cyanide consumed.

Jan 1, 2014

By Douglas E. Wolfe, Jogender Singh, Robert Miller, Dong-Ming Zhu, Jeff Eldridge

This paper discusses microstructural changes produced by two novel approaches using electron beam physical vapor deposition (EB-PVD) in which periodic strain fields/microporosity was incorporated within the large columnar grains of Zr02- 8wt.%Y2O3 (8YSZ). The traditional columnar microstructure of partially stabilized zirconia has been slightly modified to produce a lower thermal conductive thermal barrier coating (TBC) by periodically interrupting the condensing vapor resulting in microstructural modifications with diffuse or sharp interfaces and morphological changes on the sub-micron scale without changing the composition of the TBC. These microstructural modifications resulted in a 20-30% reduction in the thermal conductivity, 28-56% increase in hemispherical reflectance, improved oxidation cyclic life (over 100%), and better strain tolerance as compared to standard ZrO2-8wt.%Y2O3 deposited on platinum-nickel-aluminide and CoNiCrA1Y bond-coated MAR-M-247 test samples. The TBC with tailored microstructures were examined by various techniques including scanning electron microscopy (SEM), x-ray diffraction (XRD), steady-state laser heat flux technique, and hemispherical reflectance.

Jan 1, 2004

By Marcin Ziemski

This paper reports on an energy efficiency analysis completed as part of a research project looking at energy reduction opportunities in minerals processing operations. The plant discussed is a gold production facility owned by Newmont Gold in the Tanami region of central Australia. Due to its remote location, lack of nearby gas pipeline or power grid, the operation has been completely dependent on diesel fuel for its electricity generation and transport needs. The mine and processing plant use electrical power at a rate of 12MW to 18MW, resulting in a monthly electricity cost of over US$1.5M. The high cost of diesel combined with an impending power generation capacity shortage drove Newmont to undertake the energy efficiency study. An energy audit of the plant showed opportunities for significant energy savings through the strategic use of waste heat, fuel replacement alternatives and renewable energy sources.

May 1, 2007

By Jerry C. Tien, Yingjiazi Cao

"Coal spontaneous combustion (SponCom) is a natural phenomenon in underground operations, which can either happen naturally or be triggered by human activities. For underground operations, espe-cially in coal, SponCom can happen frequently as a result of air leakage, although its incubation period may vary depends on types of coal and surrounding environment, resulting in uncertainty in control. In China, most of the underground coal operations now use longwall mining method because of its superior safety, high productivity and efficiency. With an increased popularity, there is also an increasing necessity to study spontaneous combustion, its occurrence and management. There have been many theoretical analysis and experimental studies over the past half century hoping to understand the occurrence of coal combustion and its control measures to better understand the occurrence and to design controlling measures to limit the dam-age it causes. In this paper, research on coal spontaneous combustion fundamentals from these three aspects will be reviewed, gaps highlighted and possible directions for future studies. INTRODUCTION The history of anthropic development is the history of human's energy utilization progress. From the first usage of fire, people have been continuingly seeking energy resources on earth. Coal, as an abundant, economic and convenient source of fuel quickly became indispensable and made significant contribution to economic growth worldwide. With technology and societal development, people are becoming more and more coal-dependent, but at the same time, problems of fossil fuel combustion came into sight. In global coal mining industry, spontaneous combustion has now presented one of the most challenging safety issues, it is also believed that it has contributed significantly toward the climate change. It is essential that more effort be invested to examine the cause of SponCom and its control measures. Coal SponCom is a complex process, with both physical and chemical inter-actions among various interrelated factors such as local airflow distribution, ventilation pressure, methane emissions (if any), and physical surroundings underground. With the advent of powerful computers, simulation techniques and af-fordable modelling packages in recent years, significant advances have been made in understanding sponta-neous combustion. But because of the complex nature of combustion and varying underground conditions, there are still areas that need further examining. This paper will focus on illustrating the current research of coal spontaneous combustion and addressing research gaps and future study areas."

Jan 1, 2019

By C. Stamberg, W. McGuire, R. C. Carlson, L. W. Vollmer

"The selection of materials and pre-cautionary measures for handling natural gas and condensate containing aqueous hydrogen sulphide are presented. Based on the results of a pilot production test and laboratory studies, together with several years . of operating experience, it was found that the behaviour of materials in sour gas environments can be predicted sufficiently accurately for engineering purposes.The selection of proper materials is essential for preventing sulphide-stress cracking. Where high strength materials are not required, low car-bon steel is used. Components requiring high tensile strength and hardness characteristics should be made from K-monel or properly heat-treated carbon-manganese-molybden-um and AISI 4140 steels. Welded connections are a potential source of sulphide-stress cracking. Consequently high quality welding and strict inspection are suggested as the most economical precautionary measures available.A maintenance program based,. where possible, on visual inspection of equipment and/or test spools located at strategic points should be used to follow weight loss and putting corrosion in sour gas environments. If severe weight loss or pitting corrosion is encountered, inhibitors have been found to be an effective deter-rent."

Jan 1, 1960

By F. R. Archibald

SINCE the opening of the Beattie mine, in 1933, the concentrate produced by flotation has been considered refractory. As the gold extraction by cyanidation was poor, the concentrate, during the first four and a half years of operation, was shipped to a smelter for further treatment. After the installation of the cyanide plant, in 1934, seventy per cent of the gold in the concentrate was recovered before shipment to the smelter. In 1937, a roasting plant was built so that treatment might be complete at the mine. Much experimental work had been done by a number of investigators prior to the installation of the roasters, but none of them had seriously attempted to identify the causes of, or the elements responsible for, the refractory behaviour of the concentrate. Intensive investigation in this direction commenced in the Beattie lab-oratory in July, 1938, has led not only to the identification of several causes contributory to the refractory behaviour, but also to revisions in procedure and principles with respect to roasting Beattie concentrate in particular and arsenical concentrates in general. The accuracy of the identification of these causes and the soundness of the principles is borne out by interpretation of roasting plant records, by improvements and simplification since applied. to plant operation, and also by laboratory and test-plant results on arsenical concentrate produced by another mine. It is the purpose here to present an account and interpretation of the laboratory investigation, together with a correlation of laboratory and plant results. Incomplete extraction of the gold by cyanidation after roasting is due primarily to the nature of the material roasted, and secondarily to the manner in which it has been roasted. There is a possibility that better extraction may be obtained by improvements in both particulars.

Jan 1, 1939

By Marie-France Caille, Carl Caumartin

"Audrey Resources' Mobrun Mine is located in Dufresnoy Township some 30 km to the northeast of Rouyn-Noranda. The Mobrun tine deposits consist of two major massive sulphide lenses; the newly discovered 1100 lens located 450 m south of the Main zone, and one ntellite lens, the 850-870-930 complex.The 1100 lens is hosted in a large pyroclastic unit bounded to the mouth by rhyolite and andesite flows and by a thick rhyolite unit to the art h. stratigraphically belon the three lenses. It consists of approximately 15 Mt of massive sulphide, of which 10.4 Mt are of economic ade. The Main lens lies comformably above thick rhyolite flows, ecciated and pyritized by the sulphide horizon, and is overlain by ttercalated ash tuffs and rhyolites which host the over-lying satellite ns. The Main lens consists of 3,3 Mt of massive sulphide, of which 523 000 tgrade0.80% Cu, 2.44%Zn,30.19 g/t Ag, and2.2 g/t Au he richer satellite lens (180 000 t) is part of the same volcanic stem and resulted from a resurgence of hydrothermal activity. ructure played a role in the final geometry of the deposits but did not eatly affect the volcanogenic and stratabound nature of the lens. Total production since the start of operations in 1985 amounts to 58 000 t and is restricted to the Main lens. Production from the 100 will come onstream in 1992 as ore reserves from the Main and e satellite lenses are exhausted.RESUMELa Mine Mobrun de Ressources Audrey inc. est située dans le mton Dufresnoy, a quelque 30 km au nord-est de Rouyn-Noranda. lle comprend deux lentilles de sulfures massifs d’importance majeure ~i sont les lentilles 1100 et Principale, et une lentille satellite qui est complexe 850-870-930.La lentille 1100, la plus ancienne, est contenue dans une épaisse 1ite pyroclastique bordée, au sud, par des coulées de rhyolite et d’andésites, au nord, par une épaisse unité rhyolitique. Cette lentille contient environ 15 Mt de sulfures massifs dont 10,4 Mt à teneur économique. La lentille Principale repose sur d’épaisses coulées rhyolitiques brechifiees et pyritisees à proximité de l’horizon de sulfures; elle est recouverte de tufs a cendres et de rhyolites interlitees qui contiennent la lentille satellite. La lentille Principale est constitute de 3,3 M t de sulfures massifs dont 1 523 000 t sont économiques avec une teneur moyenne de 0,80% Cu, 2,44% Zn, 30,19 g/t Ag, et 2,2 glt Au. Faisant partie de ce second épisode volcanique, la riche lentille satellite (180 000 t) temoigne d’une recrudescence de l’activité hydrothermale. La structure joue un rôle important dans la géométrie finale des dépôts mais ellen' affecte pas, de fa~on significative, la nature volcan génique des lentilles. Depuis le début des opérations, en 1985, la production totale est d’environ 568 000 t, provenant essentiellement de la lentille Principale. La mise en production de la lentille 1100 est prévue pour 1992, alors que les réserves des lentilles Principale et Satellite seront probablement épuisés."

Jan 1, 1990

By L. C. So, S. Faucher, S. Mostaghel, D. Sauter, S. -Y. Oh, S. K. Lee

"Molten material from pyrometallurgical furnaces is tapped at high temperature, carrying a large amount of heat. Traditional handling methods of slow air cooling or water granulation do not allow for the recovery of heat from slag and matte. Furthermore, water granulation adds an inherent safety risk of explosions. Recently, there have been numerous studies into processes attempting to recover waste heat. However, most of them have never been commercialized due to numerous challenges including scalability, cost, low heat recovery efficiencies, and difficulties in heat utilization. Ecomaister-Hatch has recently developed and commercialized a reliable and simple dry atomization system that allows for heat recovery while eliminating the use of water. Comparisons of pilot and commercialized dry atomization and heat recovery technologies will be presented and challenges of these technologies will be highlighted.INTRODUCTION Slag has traditionally been regarded as an undesired waste product from smelting operations with slag management focused on removal and disposal of “waste”. Over 500 million tonnes of slag are produced per year, carrying with it ~220 TWh of energy (Barati, Esfahani, & Utigard, 2011). Depending on the process, the energy content of slag ranges from 10-90% of the total energy input (Barati, 2011, Rodd, 2010). There has therefore been great interest in recovering energy from slag. Slag handling methods can broadly be classified into three categories: (1) dumping and slow cooling, (2) wet granulation and (3) dry granulation. As discussed below, only dry granulation routes are amenable to heat recovery. Slag dumping involves the slow cooling of molten material and crushing of the resulting solid. In this process, slag is dumped on the ground directly from furnaces or transferred to slag pots that are moved by rail or haulers and then dumped on the ground. The molten material is left to cool and solidify until it can be broken and handled by heavy machinery."

Jan 1, 2017

By Tanai Marin

Modelling of pyrometallurgical processes can become extremely challenging when the process involves complex chemical reactions, phase change, multiphase flows, heat and mass transfer and fluid flow. Traditionally modelling involving complex thermodynamic equilibrium and thermochemistry are treated separately from problems in which transport phenomena are dominant, such as CFD and heat transfer studies. The separation is also necessary due to the lack of modelling tools that can effectively couple both solution thermodynamic and transport phenomena or even multiphysics problems. However, there are, quite often, problems in high temperature process metallurgy in which it is not possible to simplify this two modelling approaches. Typical cases of this are for example, the modelling of slag freezing on furnace walls (electric or flash furnaces) to create a protective layer in front of the refractories hot wall, the formation of build up from the matte or metal phases at the hearth of the furnace, calcine smelting from charging piles into slag phase, etc. The problem is even more challenging in nonferrous pyrometallurgy as most, if not all, of the condense phases are highly non ideal solutions involving several components and exhibiting complex crystallization paths and miscibility gaps, such as the Fe-Ni-Cu-S matte, FeO-Fe2O3-SiO2, FeO-MgO-SiO2 slags, etc. In this paper, an approach to model coupled problems involving multiphysics and solution thermodynamic is presented. The approach consists in developing in-house a library containing the Gibbs energy minimization routines and using the local equilibrium concept for process modelling from a multiphysics commercial software (COMSOL). Simple test cases, such as building a non-ideal binary phase diagram on a CFD package is presented, the limitations and of other classic approaches such as equilibrium or Scheil cooling are discussed and compared to this model.

Jan 1, 2015

By H. S. Price, F. N. Kissell, R. C. McCulloch, J. C. Edwards

"The methane em1ss10n from deep coalbeds which are actively mined is a serious problem facing the mining industry today. Pinpointing the source of methane and predicting the emission of this gas from these coalbeds is necessary if preventive techniques are to be effectively used to control methane emission. In general, because most coalbeds have water associated with them, the system to be studied may be either single-phase (methane gas) or two-phase (methane and water). Because coal mine geometry is complex and the fluids have variable properties as functions of pressure and methane concentration, the differential equations describing the flow of methane and water are not amenable to analytic solution, but must be solved numerically using high-speed computers. This paper presents the development of such a complex mathematical model along with some preliminary applications of the model to methane emission from one- and two-dimensional coalbeds with and without water present."

Jan 1, 1973

By Fazel G. Jahromi, Ahmad Ghahremaninezhad

Enargite (Cu3AsS4) is a major complex copper mineral and often is a carrier of invisible gold particles. Pyrometallurgical treatment of enargite is challenging due to the arsenic release to the environment. Hydrometallurgical treatment, on the other hand, appears to be a promising alternative for enargite processing. In an atmospheric enargite leaching process both the copper and arsenic from the mineral can be leached into a sulphuric acid solution and the arsenic can be simultaneously precipitated as ferric arsenate. The unlocked gold in the residue then can be recovered in a subsequent cyanidation circuit. The downside of the atmospheric enargite leaching in sulphate solutions is the slow leaching kinetics. In this study the effective parameters of the atmospheric enargite leaching process in ferric chloride media were investigated. All the experiments were carried out at temperatures below 100 °C. The process parameters that were investigated in this study included ferric, chloride, sulphate and cuprous concentrations, temperature, mixing rate and leaching slurry pulp density. It was found that the copper recovery rate increases with the addition of cupric chloride and also with raising the temperature. The highest leaching kinetics and the highest overall copper recoveries were achieved when cupric was initially added to the leach solution and at 90 ºC.

Jan 1, 2015

By G. W. Adams

Foreword While the literature on radium is voluminous, there is no single publication available from Canadian sources which attempts to cover at all fully the world radium industry. The comparatively recent developments in the Wilberforce area, and the consequent arousal of public interest in radium, seemed to call for the publication of such a paper which would be intelligible to the layman. To satisfy this apparent need, the writers submit this paper which contains material derived from various sources, and for which the writers make no claim of originality. Direct references are made throughout the paper to sources of information.

Jan 1, 1931

By Mary A. Wells, Amir Hadadzadeh, Mark A. Whitney, Stephen F. Corbin

In an effort to produce less expensive titanium sheet via roll compaction, the room temperature compaction behavior of titanium sponge granules (99.9% pure, Alfa Aesar) was studied under uniaxial die compaction. The titanium sponge granules were irregularly shaped, with a high degree of porosity, having a maximum particle size of 3mm. Manual die compaction was conducted using a Carver hand press, in a hardened tool steel die with 12.61 mm inner diameter. Uniaxial die compaction in a hardened tool steel die with 9.50 mm inner diameter was also performed using a Gleeble® 3500 thermal-mechanical simulation testing system which allowed for controlled deformation rates. Compaction behavior of the titanium sponge was studied using well-established compaction equations (Heckel, Panelli-Filho and Ge), and it was observed that compaction rate influences the room temperature compaction behavior of this material. The Heckel analysis of the titanium sponge showed that the behavior of the material could be analyzed in two compaction pressure regimes. In the low pressure regime (<100 MPa) the granules exhibited high compressibility, while; in the high pressure regime (>100 MPa) lower compressibility of the titanium sponge was observed.

Jan 1, 2015