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By R. A. Campbell

The electric smelting of five lowgrade Canadian manganese ores has been investigated at the Mines Branch, Department of Mines and Technical Surveys, Ottawa. Ferromanganese, silkomanganese, and spiegeleisen were produced 1by special smelting processes from these ores since the latter were too low grade to be treated by conventional smelting methods. In one case the results were considered to be sufficiently promising to justify the construction of a pilot plant, by the Company concerned, for the further development of the process.

Jan 1, 1956

By A. A. Wessels, D. P. Allison

"Mine hoists are built to handle a certain nameplate capacity; they are specified and designed according to the required duty. However, as production capacity increases in other parts of an operation, the hoist capacity can become the critical constraint. Such a situation occurred at Lundin Mining’s Neves-Corvo operation. This paper examines how each component of the existing hoisting system was examined and optimized. Through a combination of engineering study and hoist simulations, the annual hoisting capacity was improved by 24% through increases in payload capacity and available hoisting time combined with a reduction in cycle time, while no changes were made to the hoist motor, drum or headframe. The additional payload capacity was achieved by reducing the mass of the hoist ropes and skips, and improving load monitoring systems. The cycle time was reduced through the shortening of the creep distances and increased availability through the installation of a shaft collar safety platform, alternative guide rope bushes, and superior liners for both the skips and underground measuring flasks. Enhanced cooling of the hoist electrical system was also incorporated to increase hoist availability by reducing downtime during hot summer months. The changes will increase the capacity from the current 4.5 mega tonnes per annum (Mtpa) to a planned 5.6 Mtpa and are being implemented over a 2-year period whilst maintaining the mine production during the upgrade work. INTRODUCTION Neves-Corvo Mine Neves-Corvo is primarily a copper and zinc mine producing copper, zinc and lead concentrates. The operation is owned and operated by Somincor, the Portuguese subsidiary of Lundin Mining. Located in the Alentejo district of southern Portugal, the operation is situated approximately 15 km southeast of the town of Castro Verde, where summer temperatures can reach as high as 45ºC, and approximately 220 km southeast of Lisbon. The principal means of mine access is via a ramp from surface, with the vertical shaft used to hoist ore and waste from the 700 m level, while conveyors descend from the 700 m level to transport ore and waste up from the deeper levels of the mine. The mine is highly mechanized and several different stoping methods are employed, with the most significant being bench-and-fill and drift-and-fill. The Neves-Corvo mine currently exploits five orebodies: Neves, Corvo, Graça, Zambujal and Lombador for copper and zinc-lead ores which are processed in one of two plants. All the orebodies are currently exploited over their full elevation with the exception of Lombador which is only mined down to the 220 m level, approximately the top 50% of the orebody, known as Lombador Phase 1."

Jan 1, 2019

By Arthur Dubé

An account is given of the developments brought about in the last fifteen years by metallurgical research in the field of heat treatment of steels. The practical aspects of these developments are especially emphasized. Methods of representation of the phase-change during austenitizing and sub-critical transformation of austenite are described and the importance of time-temperature-transformation charts for the planning of heat treatment cycles is shown. Special copies such as retained austenite and internal stresses developed on quenching are also discussed in some detail. Due to the interest shown currently in these problems, it has been thought advisable to describe briefly the underlying principles and present some of the results already available.

Jan 1, 1945

By Dwayne D. Tannant

The Adra tunnel near Naramata BC experienced a fire in 2010 that burned timber sets within the tunnel and caused severe spalling of rock from the roof and tunnel walls. The nature of the damage is documented and efforts completed to rehabilitate and open a portion of this tunnel to the public are described. The use of shortcrete and rock bolts is a technically and economically superior support system to timber sets as well as being far more fire resistant.

Jun 1, 2012

By Stanley G. Butcher

"Introduction Many operators in western Canada, with a background in the minerals industry, talk of ""coal beneficiation"", whereas the coal industry generally uses the term ""coal preparation"" . The sophisticated cleaning circuits and thermal drying units found in western Canada makes the term beneficiation particularly appropriate. This chapter uses standard coal preparation terminology(l,2J and assumes general knowledge of coal preparation unit processes and equipment(3,4,5). The geologic setting and mining methods of western Canada, described elsewhere in this volume, present for preparation run-of-mine coals which have particular problems. As a result the cost of preparation is a higher proportion of the total minesite production costs than in other coal fields . Preparation requirements are determined by the types of coals being produced and the markets in which they are sold. Western Canadian coals have a low sulphur content and do not require cleaning on this account. Prepared coal from western Canada has to be shipped vast distances -to the Pacific Rim countries and Ontario in particular -and the savings in transport costs justify the high costs of preparation. Factors which dictate selection and operation of the preparation processes are: i) Market specifications and coal rank. ii) Size distribution of particles and particularly the liability of coal and refuse particles to degrade during handling and processing. iii) Quantity and characteristics of the associated refuse. iv) Washability characteristics (the distribution of particles by specific gravity within each size fraction). v) Surface characteristics of the fines. vi) Variability of the raw coal. Where the product (coal or discard) has a high fines content special consideration must be given to dewatering, the removal of surface moisture, to give acceptable handle ability characteristics. In the severe winter climate of the western foothills and mountains thermal drying is necessary to prevent freezing of washed coal in stockpiles and railcars."

Jan 1, 1985

By Dawei Yu, Kinnor Chattopadhyay

In the nickel industry, molten slags produced from a Pierce-Smith converter contain significant amounts of valuable metals in the forms of oxides and physically entrained matte droplets. A slag cleaning step, which takes places in an electrical slag-cleaning furnace, is therefore required to recover the valuable metals as a common practice. Utilization of a waste material from aluminum industry (i.e. spent potlining) as a flux to improve the slag cleaning in terms of both the metal recovery and the operation efficiency was studied by simulation with FactSage program. Results show that the addition of SPL could substantially reduce the slag viscosity due to its fluoride values, thus accelerating the settling of matte droplets. The carbon value in the SPL could also help increase the metal recovery by reducing the valuable metal oxides followed by settling.

Jan 1, 2015

By H. C. L. Reemeyer

"The mining industry faces increasing economic, environmental and social challenges, as easier deposits deplete and ores become more difficult to mine and process; head grades decline; projects migrate to increasingly remote and difficult geographies; and the industry faces more stringent environmental and social standards. While these factors increase costs and risks, they also present opportunities for a more integrated approach to mining, processing, materials handling and waste management. Two key areas of risk are in tailings and water management. As mining and processing tonnage rates continue to increase, the disturbance footprints, water and energy consumption and scale of tailings storage facilities also rise. These factors can be mitigated by more selective mining, ore sorting and pre-concentration, and more intensive tailings dewatering. Such alternatives must be considered in conjunction with the selection of mining method, metallurgical flowsheets, major equipment selection, and key process design criteria. For example, increasing the grind size of a concentrator reduces energy consumption and eases tailings dewatering, but may cause challenges with metal recovery. Emerging technologies will be reviewed, and economic and environmental trade-offs for eco-efficient alternatives will be presented for metal sulfide mines.INTRODUCTION The metals mining industry faces significant challenges that can affect its financial viability and social license to operate. There has been a consistent decline in ore grades and a relentless push towards larger operations to capture perceived economies of scale. With these larger operations, the environmental footprint of mines has increased. Water and energy consumption, and resulting GHG emissions have also risen. In recent years, two issues have raised special concerns for stakeholders and companies: • Water scarcity, particularly in drier regions of the world such as Northern Chile, SW USA, Southern Africa and Australia • Tailings risks, following the high-profile failures of the Fundao tailings dam in Minas Gerais, Brazil in 2015 and the Mount Polley tailings dam in BC, Canada in 2014"

Jan 1, 2017

By D. -A Tremblay

Dynamic wetting spread factors and interfacial heat transfer coefficients were determined for aluminum droplets solidifying on copper substrates, The spread factors were determined from the droplet geometries while the heat transfer coefficients were obtained by solving inverse heat conduction problems, 1-D and 2-D heat transfer models are presented and the results they provided are compared, For the latter, a sensitivity analysis was also performed to determine the influence of thermophysical properties and boundary conditions. Experiments were alternatively carried out with three different gaseous atmospheres and the dynamic wetting spread factors were correlated to the interfacial heat transfer coefficients.

Jan 1, 2005

By J. E. Gillespie

Introduction Mineral wool may be defined as "rock, slag, or glass fibres made by a process of melting and blowing by steam or air, containing a minimum of oil and unfiberized material" (U.S. Bureau of Standards CS 117-44). The earliest production of the material was in Wales, about one hundred years ago. In the United States, the industry daces from 1870 when a plant, using slag as raw material, was established in Greenfield, New Jersey. It was not until 1897, however, that large-scale production was commenced on this continent at a plant in Alexandria, Indiana, which utilized rock from nearby deposits. Today, mineral wool is manufactured in many parts of the United States and Canada, the plants for the most part being in close proximity to deposits of suitable rock or to sources of slag. In the United States there are some seventy-five producers with a total annual capacity of nearly one million tons of wool. In Canada, in 1946, eleven manufacturers produced about fifty million square feet of batt-type mineral wool insulation material. Mineral wool is, perhaps, the most efficient of all heat-insulating materials and, moreover, it is fireproof, extremely durable, and insect- proof. Its high efficiency is due to the very low thermal conductivity of the fibres themselves and to the fact that the produce as marketed contains up to 90 per cent non-conducting air space. Depending on the degree of compression of the fibres in the manufactured product, the specific gravity ranges from 2 lb. to 10 lb. per cubic foot. Products Marketed Following are the principal forms in which mineral wool is marketed: Blanket. - Mineral wool with or without reinforcing on one or both sides, with various types of confining media, all suitably bound together.

Jan 1, 1948

By K. Janghorban

Multilayered ceramic-metal composites were produced by solid state diffusion bonding of polycrystalline alumina and three Al alloys containing 1 to 2%Sr, 2% Mg and Mg + Si (5057 Al alloy), The multilayered structures were fabricated at 610°C under a compressive stress of 3 MPa for 2 hours in He-5%H atmosphere, The ceramic-metal interfaces were studied by SEM and TEM equipped with energy dispersive spectrometer (EDS). Addition of 1 wt % Sr to Al promoted good adhesion, without producing any interfacial products, while the Al-2%Sr was poor in this regard due to the presence of dispersed A14Sr which is an intrinsic phase in the Al-Sr phase system, The Al-2%Mg alloy produced a continuous film at the interface, which was characterized to be MgAl2O4. Al alloys containing Mg and Si (5057 commercial alloy) produced not only the spinel structure (MgAl2O4), but another phase rich in Mg and Si (close to Mg2Si), These latter interfacial reaction products were not the intrinsic phases in Al-Mg alloys, and were reaction products at the Al2O3 ?Al alloy interfaces.

Jan 1, 2005

By J. P. Jylhä, A. Jokilaakso

The Outotec Flash Smelting process is widely used in primary copper production. A layer of slag on top of matte (copper–iron sulphide melt) creates a barrier through which matte droplets descend. Droplets of different sizes settle through the layer at different rates, which increases possibility of copper losses as smaller matte droplets may be removed with the slag. In this work CFD-DEM (computational fluid dynamics – discrete element method) coupling was used to simulate matte droplets settling through the slag during slag tapping. Discrete droplets and slag flow were simulated with DEM and CFD, respectively. This new approach enables tracking and solving movement and interactions of individual droplets. User-defined models were created to take coalescence and reaction kinetics into account. Coalescence created larger droplets, while the reactions decreased droplet size and increased its density. Drag caused funnelling effect, which pulled droplets towards the centre line of the descending cluster. This research is the only study known by the present authors in modelling liquid-liquid systems with the CFD-DEM coupling. Simulating coalescence and chemical reactions for discrete droplets enables more realistic simulations. However, CFD- DEM simulations are computationally resource intensive already without additional models, so a full scale industrial settler modelling still waits for further increase in computer performance. INTRODUCTION Flash smelting is a method used in copper and nickel production. In the flash smelting process, oxidation of sulphides in a concentrate is used to release energy needed to smelt the feed. In the process, copper matte is formed. Matte has copper content in the range of 55 – 70% (Sridhar, Toguri, & Simeonov, 1997), the rest is mainly sulphur and iron but has still many other impurities (Taskinen, Seppälä, Laulumaa, & Poijärvi, 2001). Oxidized iron forms iron-silicate slag while SO2 is collected for acid production (Davenport & Partelpoeg, 2015). The Outotec flash smelting furnace (FSF) can be divided in four major component: concentrate burner, reaction shaft, settler and uptake. Concentrate, flux and oxygen enriched air are injected into the reactor through the concentrate burner. The mixture then reacts in the reaction shaft forming matte and slag, which are collected in the settler, while off-gases flow out of the reactor through uptake for heat and dust recovery, and SO2 collection for H2SO4 production. The matte and slag form separate layers due to immiscibility and density difference. Raw material feed is continuous, but the matte and the slag are tapped periodically. A flash smelting furnace is depicted in Figure 1.

Jan 1, 2019

By T. L. McCall

A short description of mining practice in the Sydney coal field in general is followed by a discussion of the operations in the No. 12 colliery of the Dominion Coal Company, Limited, as being typical of the trend in operating methods obtaining throughout the field. Development of longwall mining to the present system of three walls in line is outlined, together with a summary of the cycle of operations involved in systematic operation.

Jan 1, 1944

By W. H. Gauvin, N. J. Themelis

I N ADDITION to its practical importance in the beneficiation of iron ores and in direct-iron processes, the study of the reduction of iron oxides involves many aspects of challenging theoretical interest. The complexity of the reduction process combined with the fact that under different experimental conditions the controlling stage for the reaction may not necessarily be the same, has led experimenters in this field to a wide diversity of opinion regarding the reaction mecl1anism. As a rule, each investigation has been restricted to the study of one or two variables over a comparative]~• narrow range of experimental conditions, and consequently, it be-comes necessary to examine the significance of each published work in the light of the results of other experimenters in the field.

Jan 1, 1962

By Ryan W. Siggelkow

Mines today use various methods of mining to extract ore. Because of the dangerous nature of many of these processes, remotely controlled LHD machines are being used to extract the ore from the draw point. The remote control system, although being made safer all the time, has remained virtually unchanged for many years. The basic functionality is an operator switching the machine to remote control, getting out of the cab, walking up a stand, operating remotely, returning to the cab, switching to manual, driving manually, switching to remote, and switching to manual. It seems repetitive, and time consuming, does it not? Networking, convergence, video, voice, and data infrastructures, and other technologies are growing by leaps and bounds in virtually every industry and region, except for mining. From the comfort of the living room couch, a Canadian can play hockey online with full voice conversations over the Internet with someone in Russia in real time. Yet, a mine superintendent must jump through hoops to have a private conversation with the front line supervisor underground. "Is Joe around anywhere?" If Joe hears the message, he will respond. If not, who knows? Maybe he's hurt. Maybe he's not. Where is Joe? Nobody really knows, and that is scary. Today, surface knows that the workers disappeared into the cage at 7:00 a.m. They also know that the workers will probably and hopefully return at 3:00 p.m. Is there not a better way to handle this? With such a complex industry, it seems as if, for the most part, the introduction of new technology into mining has either been overlooked or has been met with some resistance. It is time to step back, look at the process, and see how it can be improved. Key areas of focus will be safety, productivity, dependability, and cost-effectiveness.

Oct 1, 2010

By A. Roy MacLean

"In the Maritimes, there are twelve coal areas. From east to west, these include the Sydney coal field, the St. Rose - Chimney Corner, Inverness, Mabou, Port Hood, Pictou, Colchester - Debert, Springhill, Joggins - Chignecto, Beersville, Lake Stream, and Minto. The first eight are in Nova Scotia while the remaining four are in New Brunswick.In all these areas, the coal was formed during the Carboniferous period, which existed some 300 million years ago. However, within this period not all coal formation took place during the same time. There were three main intervals, which occurred at the time that the Riversdale, Cumberland and Pictou groups were laid down (Hacquebard, 1970). The oldest coals are those of the Riversdale Group. These coals were of rather limited extent, and only a few mineable seams are present, particularly at St. Rose -Chimney Corner and Port Hood. From these two areas only 2 M tons have been extracted, and 'measured' resources of 7 and 9 M tons respectively remain. The Cumberland Group coals are confined to Cumberland County and include the coals of Springhill and Joggins River Herbert -Chignecto. Some 43 M tons have been removed and only 7 M tons of 'measured' coal remain, with an addit10nal 39 M tons of 'inferred' resources. However, there are additional resources at Springhill, which will be discussed in more detail in a later section. The coals of the Pictou Group are the youngest and the most abundant, both in actual number of seams and in regional distnbution. These coals were formed during the Westphalian C and D, a time during which the main coal deposition in Europe also took place. Here belong the coals of the Sydney, Inverness, Mabou, Pictou, Debert, Beersville, Lake Stream and Minto fields. Their total production amounted to 469 M tons or 91 % of the Maritime total of 514 M tons. The remaining resources of all Pictou Group coals have been calculated at 254 M tons of 'measured' coal and 949 M tons of 'inferred' coal. As can readily be seen, the bulk of both past production and remaining resources occur in the Sydney coal field. The Sydney figures represent 73% of total production, and 87% of total 'demonstrated' resources in the Maritime Provinces. Next to Sydney, the Pictou coal field has been the greatest producer, with 59 M tons; it also has the second largest 'measured' resources, amounting to 25 M tons. However in terms of 'inferred' coal resources, the Mabou coal field, ~ith 140 M tons, ranks second to Sydney."

Jan 1, 1985

By C. H. Buck, A. J. Taylor

"In 2015 Vale’s Clarabelle Mill began the process change to enable a higher degree of Cu separation. The flowsheet modification was part of a complete divisional flowsheet change being implemented in Vale’s Sudbury Operations. This paper will centre on some of the Operational Readiness (OR) work, culminating in the commissioning of the circuit in March 2017. The emphasis will be on the implementation of an integrated test plan to prepare for the process flow change through the mill.BackgroundClarabelle Mill (CBM) began making a saleable Cu concentrate in 2006 with the installation of the Cu separation circuit. Typical separation rate was 35-40% of Cu in feed reporting to Cu concentrate based on a target Ni concentrate Cu:Ni target of 0.7-0.8. The remainder of the recovered Cu (55-60%) reported to Ni concentrate and was smelted through the Copper Cliff Smelter.In 2013 a capital project, Surface Facility Upgrade (SFU), was implemented to focus on matching the surface plants capacities with the future mine plan to maximize revenues. This was to be achieved by redistributing the metal flow, specifically Cu, through CBM to increase metal unit content through the Smelter. The amount of redistribution of Cu was determined to be based on maintaining a stable Cu to Ni ratio (Cu:Ni) in the Ni concentrate.The change in Cu:Ni ratio in the Ni concentrate would affect the Sudbury divisional flowsheet, and required process changes across the all of the surface plants. The detail that surrounds the flowsheet changes as a whole will not be discussed, but the outcome of the decisions plays a large role in the operational readiness interactions between the mill, its suppliers and its downstream customers."

Jan 1, 2018

By Anthony A. Zoobkoff

Gotcha! ? What Did I Just Agree To? ? You can?t repeat or use anything you heard. ? Did you agree before you knew what you were going to be given, told or shown? ? If you knew what you were to be given, told or shown, would you have still agreed?

May 1, 2013

By André Chagnon, Yvon Héroux

"Résumé - Cette étude porte sur l'altération de la matière organique et des argiles dans les boues carbonatés dévoniennes du faciès ""F"" de la Formation de Pine Point et ses équivalents stratigraphiques la Formation d'Evie et l'unité bitumineuse de la base de la Formation de Horn River. La matière organique se compose principalement de bitume solide et de quelques fragments de fossiles (organo­ clastes). La majorité des échantillons ne renferment que de l'illite et des interstratifiées illite/smectite.Si on compare les températures d'homogénéïsation (Th = l00°C) des inclusions fluides de la sphalérite et des dolomites associées à la minéralisation aux températures estimées à partir de la réflec­ tance de la collinite (84°C à ll7°C), l'on ne peut pas conclure à la présence d'une anomalie ther­ mique dans le district minier de Pine Point. De plus, la réflectance des organoclastes n'est pas plus élevée dans le district minier de Pine Point que dans les localités plus éloignées des gîtes. L'analyse des minéraux argileux conduit à la même conclusion : aucune anomalie thermique n'est décelable dans les unités échantillonnées à l'intérieur du district minier de Pine Point quelque soit l'indicateur utilisé.La kaolinite et la matière organique altérée, affichant des valeurs anomales de sa réflectance, se trouve essentiellement en présence de soufre et de sulfures. Cela suggère une origine authigène de la kaolinite et une altération de la matière organique reliées au phénomènes de minéralisation.Abstract- The alteration of organic matter and clays is studied in the Devonian Pine Point Formation carbonate muds, ""F"" facies, and its lateral equivalents the Evie Formation and the biturninous unit at the base of the Horn River Formation. The organic matter is mainly composed of solid bitumen with few fossil fragments (organoclasts). Most samples contain only illite and mixed layer illite/smectite.If we compare the Th(l00°C) from fluid inclusions of sphalerite and dolomites associated with mineralization to the temperatures calculated from the reflectanœ (Ro) of the collinite (84°C to 117°C), we cannot detect a thermal anomaly in the Pine Point mining district. This result is based on the reflectance values of organoclasts from the mining district that are not higher than those reflectance values measured on organic matter (OM) away from the ore deposit. A similar conclusion is reached from the clay study: none of the parameters used allow us to identify a thermal anomaly in the samples from the mining district.The kaolinite and the altered OM showing anomalous Ro values mainly occur with sulfides and sulfur. This association suggests an authigenic origin for the kaolinite and an alteration of the OM due to the mineralization events."

Jan 1, 1994

By M. Stogran-Baker, E. Legault-Seguin

"Fluorspar mining in the St. Lawrence area of Newfoundland and Labrador began in the 1930s and ended in the mid-1980s. In 2013, Canada Fluorspar (NL) Inc (CFI) discovered a new ore body, the AGS vein, which proved amenable to more economic open pit mining methods and began developing this resource. This paper discusses the flowsheet development of the AGS vein deposit. Testing at SGS began in 2009 with samples from other deposits in the area. The testwork included pilot-scale dense medium separation (DMS), laboratory-scale flotation tests to develop the flowsheet and a flotation pilot plant. The more recent work that is presented here has been devoted to the AGS vein, and included a variability testing program that gave tremendous insight into the metallurgical drivers of processing the deposit. The ore was found to be fairly variable in terms of fluorite grade, but also gangue mineralogy, which had greater implications on the DMS performance. The gangue mineralogy was also found to significantly impact the grindability characteristics of the DMS product. This paper will detail the testing conducted and the mitigating steps which were identified for the operation.INTRODUCTION Fluorspar is the industrial trade name for the mineral fluorite (CaF2), which is the primary industrial source of fluoride. There are a number of categories of fluorspar, most notably acid-grade fluorspar and metallurgical fluorspar (metspar). Acid-grade fluorspar has stringent specifications and is suitable for the production of hydrofluoric acid that is used for many applications. The typical specifications of acid-grade fluorspar are >97% CaF2 and less than 1% each of SiO2 and CaCO3, with a particle size distribution in the order of 80% passing 100 µm. Metspar is typically used for metallurgical purposes, typically as a flux in smelting, and has significantly more relaxed specifications (< 15% SiO2). The principle source of fluorspar in Canada has been from the Burin Peninsula in Newfoundland and Labrador. More than 3 million tonnes of fluorspar were produced there between 1940 and 1978 and from 1987 to 1990, when production ceased (Fulton & Montgomery, 1994)."

Jan 1, 2018

By N. V. Mel'nikov

This paper discusses the reserves of oil, natural gas and coal in the USSR, with particular attention to the future role to be played by coal in supplying the energy fuel resources of the country.

Jan 1, 1972