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TRE ? worldwide leader in InSAR ? Spinoff of Polytechnic University of Milan ? Numerous patents for cutting edge technology (e.g. SqueeSAR?, PSInSAR?) ? Focus solely on InSAR with over 13 years experience ? ISO 9001 quality certification ? Powerful scalable parallel processor to handle all jobs What can InSAR provide for mining? An advanced suite of tools for monitoring ground deformation over mine sites: ? Deformation maps ? A dense network of measurement points ? Time series ? Cross sections of surface profile evolution

Aug 1, 2013

By Rodney Trevor Jones, Arthur Robert Barnes

Anglovaal Minerals acquired the Nkana slag dump from Zambia Consolidated Copper mines (ZCCM) in 1998 and embarked on an ambitious project to pioneer the recovery of cobalt from slag using DC smelting technology. Anglovaal Research Laboratories performed initial pioneering smelting tests in a 250 kW DC furnace over a 3-year period before engaging Mintek for three piloting campaigns at the 1.5 MW level. Mintek had previously developed a reductive smelting process, patented in 1995, using a DC arc furnace for the recovery of cobalt from slags. The results of the pilot-plant test campaigns were used as the basis for engineering the commercial 40 MW operation installed at Chambishi Metals plc in Zambia in 2001. This paper traces the development of understanding of the metallurgical fundamentals ultimately used to predict furnace performance, reviews some of the extreme technical challenges faced, how solutions were identified and highlights some of the critical issues identified during piloting and how these impacted both positively and negatively on the final commercial operation.

Jan 1, 2011

By Fred A. Webber

STEEL ROPE WIRE is one of the more specialized commodities among the many grades of highcarbon steel wires. In its production there are many metallurgical aspects of interest from the steelmaking on through the final stages of wire drawing. We produce rope wire in an integrated mill com prising all the operations from the blast furnaces to finished wire drawing in the wire mills. Steelmaking is carried out with close control on hot metal, selection of scrap, and fluxing materials. The basic open hearths are of 170 tons capacity. Steel is teemed into 19 1/2 in by 19 1/2 in big-end-down molds and is hot-topped with the use of clay refractory hot-tops. The weight of this ingot is 6,900 pounds. All high -carbon steel ingots are charged hot into the soaking pits and are then rolled through the blooming mill in 16 p asses to a bloom ax~ in. by 41/2 in. and approximately 65 feet long. Necessary bottom and top crops are taken on the bloom as it passes from the blooming? mill to the billet mill. The still hot bloom is continuously rolled through the billet mill in . 5 passes to a 2 3/8 in. square. Billets are cut to 32 feet in length by a flying shear and then allowed to cool on the hot bed.

Jan 1, 1957

By K. Muehlenbachs, J. U. Stemler

"Abstract - The Boston deposit is a recently discovered Archean lode-gold deposit located approximately 700 km northeast of Yellowknife, in the southern portion of the Hope Bay volcanic belt. Primary H2O-CO2-NaCl fluid inclusions associated with gold mineralization at Boston are of low salinity (4.6 ± 1.4 eq. wt.% NaCl, n = 182) and contain pure CO2. Homogenization temperatures of liquid-phase inclusions average 270° ± 33°C (n = 141), but some fluid inclusion assemblages contain coexisting liquid- and vapor-phase inclusions that homogenize near critical conditions, suggesting phase separation. In these groups, liquid-phase inclusions homogenized at 299° ± 25°C (n = 24), and vapor-phase inclusions homogenized at 338° ± 28°C (n = 18). These temperatures overlap within error, and a median temperature of ~320°C is taken as representative of trapping conditions within the veins. An approximate pressure of 2-3 kbar was estimated from fluid inclusion isochores at this temperature. Stable isotopic compositions of carbonate minerals from the mineralized zones range from -4.7‰ to -3.1‰ in d13C, and from 11.2‰ to 12.8‰ in d18O; quartz ranges from d18O = 12.8‰ to 14.9‰; and pyrite ranges from d34S = 2.1‰ to 3.5‰. The d18OH2O, d13CCO2, and d34SH2S values of the fluid calculated from these minerals at 320°C are 6‰-9‰, -2.4‰ ± 0.6‰, and 1.5‰ ± 0.5‰, respectively, and are intermediate between metamorphic and magmatic compositions. A unique source for the fluids cannot, therefore, be constrained from these data. Petrographic and geochemical data for the Boston deposit are consistent with data from other Archean lode-gold deposits worldwide, implying that the Boston deposit formed in a similar environment and from similar types of fluids. These results suggest that the Hope Bay volcanic belt may represent a major new mesothermal gold belt in this part of Nunavut. Sommaire - Le gîte Boston a été récemment découvert à environ 700 km au nord-est de Yellowknife dans la partie sud de la ceinture volcanique de Hope Bay, il s’agit d’un gîte d’or filonien d’âge Archéen. Les inclusions fluides primaires de H2O-CO2-NaCl associées à la minéralisation aurifère du gîte Boston présentent une faible salinité (4.6 ± 1.4 eq. pds.% NaCl, n = 182) et contiennent du CO2 pur. La température d’homogénéisation des inclusions à phase liquide est en moyenne de 270° ± 33°C (n = 141), mais certains assemblages d’inclusions contiennent des phases liquides et gazeuses coexistantes qui s’homogénéisent dans des conditions quasi critiques, suggérant qu’elles résultent d’une séparation de phase. Dans ces groupes, les inclusions de phase liquide s’homogénéisent à 299° ± 25°C (n = 24) et les inclusions de phase gazeuse s’homogénéisent à 338° ± 28°C (n = 18). Ces températures se recoupent à l’intérieur des limites de l'erreur de mesure, et nous considérons qu’une température médiane de ~320°C est représentative des conditions de piégeage dans ces veines. Les isochores permettent d’estimer une pression d’environ 2-3 kbar à cette température. La composition des isotopes stables des carbonates dans les zones minéralisées s’étend de -4.7‰ to -3.1‰ pour d13C et pour de 11.2‰ à 12.8‰ pour d18O; les valeurs de d18O pour le quartz varient de 12.8‰ à 14.9; et les valeurs de d34S dans la pyrite vont de 2.1‰ à 3.5‰. Les valeurs de d18OH2O, d13CCO2, et d34SH2S du fluide calculé à partir de ces minéraux à une température de 320°C est de 6-9‰, -2.4‰ ± 0.6‰, et 1.5‰ ± 0.5‰ respectivement, reflétant des conditions intermédiaires entre des compositions métamorphiques et magmatiques. Il n’est donc pas possible d’identifier une source unique pour ces fluides à partir de ces données. Les données pétrographiques et géochimiques du gîte Boston sont similaires à celles d’autres gîtes d’or filoniens ailleurs dans le monde, ce qui implique que le gîte Boston s’est formé dans un environnement similaire à partir des mêmes types de fluides. Ces résultats suggèrent que la ceinture volcanique de Hope"

Jan 1, 2006

By Sean Dessureault

Information technology (IT) initiatives in the past have tended to be sold on their ability to maximize resource output and return on capital by using assets more effectively and efficiently. Many IT projects fail, not delivering return on their investment. This is known in the IT industry as the ?productivity paradox,? where increasing investments in IT do not result in comparable increases in productivity. Experiences and studies of most business sectors reveal that this paradox is rooted in the false assumption that more IT spending automatically results in financial benefit, whereas the true source of benefits is in how effectively IT is used. Most business sectors have accepted that the reengineering of processes is required to gain the full benefits promised of IT. A mining operation has organizational processes similar to most business sectors but unique operational processes. The lessons of changing business practice in more common business processes such as inventory control and customer-supplier relationships can be adequately transposed into a mine. The unique operational processes in mines, in turn require unique redesign efforts. Several enabling information technology opportunities have recently become available, such as more integrated mine production management systems and tactical manger training simulators. This paper reviews the latest IT products and ou lines the processes and kinds of change that will be required in order to benefit from these new investment options.

May 1, 2002

A pilot scale AG milling campaign was conducted at the AngloAmerican Platinum pilot plant in South Africa. Different blends of hard:soft (silicate:chromite) and coarse:fine particles in the AG mill fresh feed were tested. The effects of multi-component feed on the pilot scale autogenous grinding are presented in this paper, and can be used as a guideline for multi-component feed blends for AG milling. Preliminary modelling and simulation for the multi-component AG mill model are also included.

Jan 1, 2012

By G. H. K. Pearse

Sulphur is derived from both 'voluntary' and 'involuntary' production. The former category includes sulphur obtained from elemental sulphur deposits and from pyrite and gypsumanhydrite deposits. Sulphur in the latter category is produced by pollution abatement at fossil Juel plants and from treatment of metallic sulphides. Canada is the world's largest sulphur exporter and third largest producer. Main resources of Canadian sulphur are sulphurous fossil fuels, metallic sulphides and native sulphur. Only the first two sources have produced sulphur in Canada 10 date; the first source accounts for over 85% of total Canadian production. Future sulphur sources will be derived increasingly through pollution abatement and decreasingly through voluntary production.

Jan 1, 1984

By P. N. Saavedra, E. A. Salamanca

"The maintenance strategies in the mining industry are changing from operative and periodic inspection strategies to a condition-based, predictive maintenance strategy centred in vibration analysis plus complementary techniques. Condition monitoring can also help to improve availability by being able to pinpoint and diagnose problems on operating machinery at an early stage. This reduces unscheduled downtime and production losses.However, in mining, for shovels operating in transient modes, with variable load and/or speed, the FFT (Fast Fourier Transform) standard approach is not directly applicable for analysis. This work illustrates how spectral order analysis and new transforms, called time-frequency transforms (TFT), allow us to monitor the shovel when it is working. Some practical examples showing the application of these analysis techniques to occasional vibrations measured on hoist and crowd transmission of a shovel are also presented. It is shown that at present, it is possible to carry out the vibration monitoring in the mining shovel while it is working, therefore avoiding the high cost of a loss of production which can occurr in traditional monitoring, where the measurement is taken while the shovel is out of production."

Jan 1, 2002

By K. K. Dehn

This study focused on determining the stability of thin shotcrete fill fences at a hard rock mine in northwestern Ontario during increased pour rates of paste backfill. Determination of the stability of the fence is needed for both personnel safety and to avoid failure of a fence. Failure of a fill fence during backfill activities would have severe impacts on production and potential hazards to nearby workers. Approved fill fences at the mine are a slender design of 10.5 centimeters of shotcrete applied to a rebar framework with burlap lined ?bedspring? backing. Approved mine standards dictate that fill rates may not exceed 1.5 meters of paste depth per 10-hour shift when pouring behind a flat fill fence. To decrease the backfill cycle time the study looked at fence stability during increased pour rates of 2.5 meters paste depth poured within a 10-hour shift. An instrumentation design was developed including pressure cells, strain gauges, and tilt-meters that were built into experimental fences to observe the effects of increased pour rates on lateral wall pressures, strain development in the rebar and shotcrete reinforcement, and physical deformation patterns along the face of the fence. The data was analyzed for overall stability.

May 1, 2007

By Alfred W. G. Wilson

MR. F. E. LATHE: In studying any subject whatever, one should at least occasionally stand back from the canvas, as it were, and take a broad view of the picture. It is such a view of the subject of industrial minerals that Dr. Wilson has given us today, and, in consideration of our efforts to utilize Canada's resources to the utmost in the present emergency, it seems most timely. I shall confine my remarks on the subject to the resources of the atmosphere and hydrosphere. We seldom stop to realize our dependence upon the atmosphere, not merely as a source of the oxygen we breathe but also of other indispensable elements. As recently as the beginning of the present century, grave concern was felt lest the rapidly increasing population of the world should ultimately starve for lack of the nitrogen required for crop growth. I recently noticed a reference to the Scientific American for March, 1890-just fifty years ago-in which an account is given of work on the fixation of nitrogen, which, said the article, "leads to the conclusion that while cyanides and ammonia may be thus produced experimentally, there are as yet insuperable difficulties in the way of adapting those methods to industrial purposes". Y et, in the early part of the present century, the development of the arc, cyanamide, and synthetic ammonia processes of nitrogen fixation was such as to remove, for all time to come the possibility of a shortage of nitrogen. Today, the atmosphere is by far our greatest source of nitrogen, and the capacity of the nitrogen fixation plants of the world is at least 4,000,000 tons annually-much more than can at present be utilized. Pure oxygen or oxygen-enriched air offers great possibilities in metallurgy and industrial chemistry, but, so far, little application has been made. In a paper presented to the Institute in 1926, 1 pointed out the theoretical savings which could be effected by the use of oxygen in burning carbon-when the gases pass off at 2,460°F., the fuel saving is no less than 50 percent. The use of oxygen on a commercial scale is intimately tied up with the question of refractories, but we should not forget that the possible changes in metallurgical practice by the use of oxygen are truly of revolutionary character.

Jan 1, 1940

By T. McCallum, B. Wellbrook, T. Ratnaweera

Leaching of copper (Cu) concentrates produces elevated concentrations of Cu and acid, which makes solvent extraction (SX) processing more challenging. Maintaining extraction targets can be more difficult with higher pregnant leach solution (PLS) grades, and variability of PLS Cu and acid can lead to increased chemical iron transfer. Diluting concentrate leach feeds with an existing heap leach inventory makes SX processing easier. However, considerations about how much to dilute and where to distribute the flow into the SX configuration must be carefully evaluated, given their impact on metallurgical performance. In this paper, characteristics of a concentrate leach feed are discussed, along with considerations for processing by SX. Also reviewed are pilot plant results of concentrate leach distribution into SX and plans for commercial testing. INTRODUCTION Hydrometallurgical processing of copper concentrates continues to gain interest from the industry. Treatment by smelting and electrorefining continues to dominate, accounting for ~80% of global copper production, but is faced with its own challenges (Li et al, 2017). The case for increased hydrometallurgical processing has been discussed as high grade ore deposits are diminishing, capital costs for smelting are high, and the environmental aspects present challenges for sustainable practice. The hydromet copper industry is also turning a corner as easily leachable copper oxide deposits are depleting, and excess SX-EW capacity exists in certain regions. The transition to hydrometallurgical processing of copper concentrates will take a bit of effort as leaching of copper sulfides is difficult and byproduct credits must be considered. Various POX leaching processes have been studied and proposed to the industry as viable practices. Of the many processes, commercial use has been practiced with the Mount Gordon Copper Process, total and partial pressure oxidation by Freeport-McMoRan at their Bagdad and Morenci, Arizona complexes, the Sepon Copper Process in Laos, and the bioleach BIOCOP™ process in Chile (Dreisinger, 2016).

Jan 1, 2019

By A. R. Miller, M. C. Bétournay, D. L. Barnes

"A number of successful proof-of-concept projects have been carried out to replace conventional power application, such as diesel and rechargeable batteries, in underground mine vehicles. This has led to the development and testing of the world’s first fuel cell production vehicle, a mine locomotive. A fuel cell loader is being built and tested.This paper provides an insight into other projects that are being carried out. Some are related to further underground applications, and some to further research, such as refueling options, power plant durability, and vehicle automation.Also outlined is an evaluation of the overall mining applications and advantages this technology can bring to underground mining, including the facilitation of automation and tele-remote operation."

Jan 1, 2003

By Susumu Tsubota

Three types of reference gold catalysts, i.e., 3wt%Au/TiO2 (Au-Ti: Type A), and 0.3wt%Au/Fe2O3 on alumina beads (AUS: Type B), and 5wt%Au/Fe2O3 (Au-Fe: Type C), were produced in a test plant scale by Sud-Chemie Catalysts Japan, INC. under the licensing of AIST. To evaluate the validity of the preparation methods and conditions used for the reference samples, elemental analyses by ICP, particle size measurements by TEM, and catalytic activity measurements for the oxidation of CO and H2 over these catalysts were made. Gold catalysts can be prepared in a large scale of ca 400g for the Au-Ti and Au-Fe catalysts, 5 kg for the AUS catalyst with good reproducibility. It was confirmed that they were available for useful as the reference gold catalysts of World Gold Council.

Oct 1, 2003

By C. Vanvoren

"Since 1975, the Aluminium Pechiney Research Centre at Saint-Jean-de-Maurienne (LRF) has been concentrating its efforts on designing, testing and perfecting the Aluminium Pechiney point-fed prebaked reduction cell.In 1979, the AP18 cell (180 kA) was industrially launched with the construction and start-up of the F line in Saint-Jean. The following generation, the AP30 (300 kA), with prototypes started in 1981, was launched in 1986 on the Saint-Jean G line. Along with cell design, efficient process control systems were developed to pilot alumina feeding and bath composition. Together, these pots are currently producing 4.6 Mt of aluminum, i.e., 18% of the world’s overall yearly production.In 1989, the research centre faced a new challenge: to push the limits for the size of a reduction cell to further improve the profitability of Greenfield projects. This new generation development was also the opportunity for a significant redesign of the Aluminium Pechiney electrolysis information system.With a track record of ten years of semiindustrial operation with three prototypes, the AP50 technology is now ready for industrial implementation and enables a significant breakthrough to be made in terms of return on investment of a Greenfield smelter."

Jan 1, 2002

By J. G. Ross

A DESCRIPTION of the block-caving system of mining as practised at the King mine of Asbestos Corporation, Limited, Thetford Mines, Que., was presented. at the Annual Meeting of the Institute held in Quebec city, in April, 1934. The paper was published in the Transactions of the Institute for 1934. There has now been recovered, by this method, one million tons of ore, and a review of experience indicates that the method was well planned and has been executed smoothly. In approaching the problem of selecting the type of mining best adapted to this deposit, the method had to be one which would be low in cost, use no wood, and not disturb the surface immediately bounding the ore-body on two sides. Prior to 1931, block-caving had been considered but rejected, as it en-tailed disturbance of the surface area which lay within a 45° angle of the lowest contemplated workings, if the practice of such mines as Ray, Miami, Inspiration, and Morency, where this type of mining has been used extensively, was followed. At these properties there have been mined large tannages at outstanding low costs, but an extensive surface area has been disturbed in each case. In some instances, townsites in the mining area have had to be abandoned, and dwellings, not considered worth moving, have been allowed to fall into the depression. A study was made of the principles involved in the various types of block-caving, the existing information on ground movement, subsidence, etc., also being carefully analysed. Toward the end of 1931, a plan was conceived whereby the country adjoining ground being caved might be held permanently in place and undisturbed. The success of such a scheme was essential to the application of block-caving at the King mine on account of property boundaries, the Quebec Central Railway right-of-way, and expense of moving buildings. Study of existing data on caving and movement of rock, caused by sub-surface excavations of sufficient unsupported area to result in failure of the backs, indicated, in practically every instance, that such movements followed certain definite laws of mechanics.

Jan 1, 1936

By Charles Camsell

If it were necessary to preface a discussion of the mineral position of the Empire by justifying one's interest in that subject, there are two points that at once suggest themselves by way of vindication. Tremendous Growth of MINERAL Consumption The first of these points has to do with the general question of the world's mineral consumption. Most thinking persons appreciate in a more or less vague way the vital rôle that has been, and is being, played by mineral products in building up the material side of our modern civilization. But, apart from that casual and almost subconscious appreciation, very few have any precise knowledge of the extent to which the growth and the operation of our vast present-day industrial structure has been made possible by, and only by, a tremendous increase in the consumption of mineral products of all kinds. The increasing use of minerals confronts us today at almost every turn. It does not matter in what direction we look-at the expansion and the change in transportation facilities, in the air as well as on land and on sea; at the increasing mechanization, not only in factory and mill but even in our domestic life; or at the constantly widening use of machinery for all phases of farm production-everywhere we meet the same phenomena of rapidly growing uses of equipment produced mainly from minerals. Without resorting to any tiresome statistics, a few figures may suffice to indicate with what enormous strides the world's mineral consumption has been advancing. The figures for recent years may be open to objection on the plea that, ever since the outbreak of the world war, conditions have hardly been sufficiently normal to give us trustworthy data-we have been living under extremes either of depression or of abnormal stimulation. During the last decade before the war, however, from 1903 to 1913, the world was moving along in a quietly prosperous manner; and we have figures, or at least reasonably reliable estimates, as to the growth in mineral consumption during that decade.

Jan 1, 1932

By A. H. Onur, S. Ural

"The Afsin-Elbistan coal deposit with its 3.4 billion metric tons of reserve is the biggest coal basin and one of the most important resources for electrical energy production in Turkey. The coal deposit is located north of Elbistan, Kahramanmaras Province, in southeast Turkey (Fig. 1).The Kislakoy sub-basin of the Afsin-Elbistan basin was selected as the first open cast mine to feed four power station blocks of 340 MW each. The mine is equipped with six identical bucket wheel excavators of the type Sch Rs (2300/5) 32. The annual coal demand of the power station is 18.5 million metric tons. The Elbistan basin encompasses an area of 900 km2, and its centre lies about 1150 m above mean sea level. The sedimentation took place mainly in the upper Pliocene period. The thickness of the coal bed varies from 20 m to 60 m, respectively. The basal part of the coal beds consists of clay, marl and sandy clay. These formations are overlain by gyttja, which may also occur in the form of calcareous ooze, enveloping coal beds. The thickness of the gyttja is up to 35 m (Otto-Gold, 1969). The coal of Afsin-Elbistan is soft coal and the quality has been found to vary considerably throughout the deposit. The thicknesses of the sterile intercalations vary from 0.50 m to 2.2 m and average 1 m in thickness. From the quality control point of view, the coal seam is regarded as upper seam where the gyttja formation occurs as sterile intercalations, and lower seam where the clay formation occurs instead of the gyttja (Fig. 2). The CaO content of upper Kislakoy coal is very high, grinding resistance is low and base to acid ratio of ash, that is, the ratio of acid oxides of metals to base, is greater than one (Ural and Onur, 2001). Contrary to upper Kislakoy coal, CaO content of lower Kislakoy coal is very low, grinding resistance is high and base:acid ratio of ash is smaller than one. Modified Impact Strength Index (MISI) tests are used to determine the grindability of the Elbistan coals (Ural, 1999)."

Jan 1, 2003

By J. D. Galloways

The northern part of the P. G. E. railway traverses and opens up that part of the province known as the Cariboo district, comprising the Cariboo and Quesnel Mining Divisions, which are a part of the Northeastern Mineral Survey District. Williams lake, a divisional point on the P. G. E. is near the southern boundary of the Quesnel Division and from this point the railway runs northerly to Quesnel, its present terminus. From Quesnel the railway is projected and partially constructed to Prince George on the Canadian National railway; therefore its general trend is northerly through the heart of the Cariboo district. Early History There is no need to outline at any length the early history of mining in the Cariboo. It is sufficient to say that the great gold rush to the Cariboo, in the early sixties, was practically the commencement of mining in British Columbia. These early placer mining operations centred around the old towns of Quesnel Forks, Keithley Creek, Barkerville and Van Winkle, the latter now called Stanley. Many millions of dollars of placer gold have been taken out and the end of production is not in sight yet. The maximum yearly production was reached about 1863, after which there was a gradual decline in output. During the war years production was at a very low figure but a steady, even if small, increase has occurred in the last three years and prospects are encouraging for a much greater output.

Jan 1, 1925

By J. A. McCamley

Gypsum scrap generated from wallboard manufacturing, construction and deconstruction activities in North America, Europe and Japan is a recognized environmental problem. Landfill disposal of this gypsum scrap is problematic, with deposits often creating hydrogen sulphide emissions and metallic sulphide groundwater leachates. Of these regions, Europe is the most advanced in dealing with the issue having enacted legislation, which will come into effect in July 2005 that will strongly encourage gypsum recycling throughout the EU. An estimated 10% to 17% of all gypsum used in the wallboard industry becomes recyclable scrap, which represents approximately 1% of the total waste stream in North America. In the United States, 2.5 to 4.5 Mt of gypsum scrap is generated each year; the volume is similar in Europe (the percentage of total tonnage is less because of the higher use of brick and concrete). The Greater Vancouver region of British Columbia has banned gypsum from its landfills, and as a result, all gypsum scrap is now recycled. New West Gypsum Recycling, a Canadian firm, uses its proprietary technology to process large quantities of gypsum scrap that is reincorporated into new wallboard, at percentages ranging up to 25%. The operation of New West Gypsum Recycling Inc. of Langley, Vancouver is examined as a case study and recommendations are provided as to how other urban regions can implement similar gypsum scrap recycling programs.

Jan 1, 2004

By J. C. Roy, S. Couture, C. Barbeau

The chemical composition of the asbestos tailings from different mines in the Eastern Townships of Quebec are fairly uniform in composition. The serpentine minerals antigorite and chrysotile form about 85 to 90 per cent of the total. Iron oxides add another 7 to 10 per cent; magnetite represents about 70 per cent of the oxides. Chromite is present in amounts of about 0.5 per cent. The average contents of elemental magnesium, iron and nickel are 23, 6 and 0.25 per cent respectively.

Jan 1, 1972