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By Ree Llewellyn

"It has been estimated conservatively that the costs of wear damage and friction in the Canadian mining and mineral processing industry amount to over one billion dollars per year. These are mainly incurred through the repair or replacement of worn parts and production losses from related equipment downtime. The selection and application of the most appropriate wear protection components and systems, can thus have a very significant influence on productivity, profitability and global competitiveness.Details are presented of the wide diversity of materials used to counteract the varied and often complex wear attack mechanisms that occur in surface mining. The majority are various forms of steels and irons with generally very high hardness. However, they also include relatively soft elastomers and polymeric products.The main characteristics and applications of the different classes are reviewed. Case studies record significant performance improvements achieved through more judicious selections. Finally, some new developments which reduce maintenance charges by substantially increasing wear component life, are described."

Jan 1, 1996

By R. Khanna, I. Mansuri, S. Devasahayam

"Recycling polymer based end-of-life materials as carbon resources for a partial replacement of coke/coal can make important contributions towards enhancing the environmental sustainability of steelmaking processes. An in-depth high temperature (1550°C) investigation has been carried on waste CDs/DVDs focussed specifically on char generation, characterization and dissolution into molten iron. The simultaneous presence of carbon and oxygen in polymeric chains on polycarbonate substrates resulted in the generation of a significant pore structure and exposed surfaces. Carbon dissolution studies into molten iron were carried out on the raw polymer as well on chars; high levels of carbon pick-up were observed in both cases after 15 minutes of contact at high temperatures. INTRODUCTIONOver the past sixty years, plastics have played an important part of our daily lives and are being increasingly used in all aspects of the global economy. More than 260 million tons of plastics are produced annually worldwide. Their rapid growth and extensive utilization with a short life span (such as packaging) has created a massive waste problem. Although the waste plastic component in municipal solid waste (MSW) amounts to only about 10 %, plastics have a high volume-to-weight ratio and these are generally not biodegradable. In Australia, ~19.20 % of plastics were recycled in 2009-2010 (PACIA, 2010); with the total consumption being estimated at 1,501,258 tonnes, 288,194 tonnes of plastics were recycled. There are serious environmental concerns with the two key waste management options, i.e. land filling and incineration, and there exists an urgent need for developing alternative recycling approaches. In this paper, we focus our attention on recycling waste CDs/DVDs polycarbonate substrates as a carbon resource in steelmaking.CDs/DVDs used for music/data/image are made from aromatic polycarbonate resin (hereafter abbreviated PC). This resin is also widely used as an engineering plastic in applications such as automobiles, mobile phones, notebook type personal computers, cameras & video cameras, electric & electronic appliances, fire equipment, life & living goods, roofing sheets, etc. High consumption and growth (~10% annually) of PC utilization is attributed to its excellent properties such as outstanding impact resistance, transparency, heat resistance, and dimensional stability. The molecular formula and composition of PC resin is given below:"

Jan 1, 2012

By E. R. Hughes

Introduction Situated 182 miles east of Vancouver, on the Kettle Valley branch of the Canadian Pacific railway, the Princeton coal field is readily accessible to the Coast markets. The area covers approximately forty square miles and present indications are that the deposits should contain at least 300,000,000 tons of coal. Comparatively little development has yet taken place in this coal field. Since the commencement of recorded output, the collieries operating in this area have produced 1,640,518 tons of coal. The coal field proper includes only the Tertiary deposits adjacent to the town of Princeton and does not include the Coalmont or Nicola deposits. Production has never been on a large scale. The largest annual output from any property was 81, 780 long tons mined at the Granby colliery in 1940. Coal output was first recorded in 1909 and since that time fifteen properties are reported to have either mined coal or to have done prospecting or development work; of these, only two are presently active. However, none of the properties now inactive were closed because their coal resources were exhausted. The accompanying key map shows the extent of the Princeton coal field, and the location of the coal mines and prospects in this field General Geology The Princeton field is underlain by rocks of Oligocene age and is one of the series of more or less isolated Tertiary lake basins in which coal, or lignite, has been found in the interior of British Columbia. Resting on the Nicola group rocks of Triassic age, the Princeton sedimentaries consist of sandstones, conglomerates, shales, bentonite, bentonitic clays, and several seams of coal. Tertiary volcanics occur both above and below the stratified rocks and in places they have been thrust through the overlying measures. In some areas, the coal has been burned to a red ash as the result of vulcanism, while in other parts some of the moisture has been driven from the coal, thus improving the grade. The field can best be described by dividing it into two areas: the Southern area, lying to the south of the town of Princeton, where most of the mining has been done; and the Northern area, to the north of Princeton, where very little development has taken place.

Jan 1, 1947

"Option pricing is used in finance for valuing options to buy (or sell) shares at some future date because it provides a convenient framework for quantifying values subject to uncertainty. As one of the main sources of uncertainty in mining is the price (sales) of the metal, this approach can also be used for valuing mining projects.The first part of this paper reviews options and option pricing; the second part presents the approach developed by Brennan and Schwartz (1985) for using option pricing to value natural resources. Several applications of this methodology have been published; these are described. From a mining point of view, the assumptions made by Brennan and Schwartz are too simplistic. The weaknesses are discussed with a view to improving an apparently promising new way of assessing the value of projects. IntroductionThe collapse of the British merchant banking group, Barings, has highlighted the risks that can be incurred by speculators and arbitragers in the futures and options markets. But this negative attention on futures and options should not make us forget their positive aspects. They can provide producers and consumers of metals with more predictable sales prices. The introduction of the new traded average price options, TAPOS, by the London Metal Exchange in January 1997 is a response to this need. Equally important, the theory that the finance industry has developed for valuing options provides an interesting framework for valuing mineral projects as well. While this paper was being revised, the South African gold mining house, JCI, announced that it was using a methodology based on option pricing for valuing the mineral rights to deeplevel gold resources (see Box 1)."

Jan 1, 1997

By Rob Scott

Making a difference with Zinc & Health Two billion people do not get enough zinc in their diets. Every year 450,000 children die from complications arising from zinc deficiency Our Zinc Alliance For Child Health partnership with CIDA and Micronutrient Initiative, our involvement with UNICEF through the IZA and our partnership with BASF are gaining wide recognition. Sustainability at Teck ? Integrating into our Core Business Strategy Our strategy Long term goals Our approach Managing risks and finding opportunities Our progress Early reports Moving Forward Metrics and indicators

May 1, 2013

By V. C. Pandolfelli, L. Paulino, C. E. Zangiacomi

The continuous improvement in aluminum industry over the last years has increased metal output at lower cost. The potlining plays an important role in this regard due to high cost involved and more recently in its environmental aspects. In order to increase potlife and thus minimize the aluminum cash cost, a systemic approach is needed, through investigating the main cathode failure mechanisms by using a pot autopsy as a powerful tool, and then making the necessary chances to achieve extended potlife. In addition, preheating and pot start-up may also damage the cathode if not performed with an appropriate technique or even if the lining materials are not specified correctly, among other factors. All these aspects will be presented and discussed in this paper. Increased potlife, especially now that the current is reaching values up to 300kA, will allow aluminum plants to match their goals more efficiently at lower costs.

Jan 1, 2006

By Q. Han

A modified cast-on method has been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. Data obtained from a push-out experiment indicated that the bond strength was much higher than that obtained using the Al-Fin approach. This paper introduces this modified method in four sections: the coating of the steel pins, the cast-in method, microstructure characterization, and the bond strength. The section on the coating of the steel pins contains coating material selection, electro-plating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section on cast-in method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.

Jan 1, 2015

By J. O'Leary, R. Cannell, D. Honsberger

"The Scully Mine deposit lies within the group of metasediments that together comprise the rocks of the Labrador Trough. The ore itself still retains the bedding characteristics of the parent rocks and on this basis has been divided into three main members, namely: Upper, Middle and Lower. The Upper and Lower both show many of the bedding characteristics of the cherty taconites of the northern U.S.A.; the Middle member is a coarse-grained friable specularite rock. The ore minerals are hematite (normally present in the specular variety) and magnetite, although the latter rarely occurs in concentrations greater than 20 per cent. Gangue minerals are quartz and the hydrated iron oxides. Manganese oxides also occur as accessory minerals. The outcrop area of the orebody is in excess of 2 square miles, displaying a complex pattern of faulting and folding, which has been formed as a result of at least two orogenic periods."

Jan 1, 1972

By L. Sun

In this work, strontium doped lanthanum ferrite (LSF) and their composite cathodes were fabricated by screen printing on yttria-stabilized zirconia (YSZ) electrolytes. Their electrochemical properties were evaluated by using electrochemical impedance spectroscopy and steady-state polarization methods. All the cathodes were screened by comparing their total polarization resistances before and after activation processes at different temperatures. The improved LSF composite cathodes were also screen-printed on YSZ/NiO half cells to fabricate solid oxide fuel cells (SOFCs), which have reached the output power densities of 170 mW/cm2 at 650 °C, 230 mW/cm2 at 700 °C, 304 mW/cm2 at 750 °C and 388 mW/cm2 at 800 °C.

Jan 1, 2005

By D. R. Pyke

Many of the gold deposits in the Timmins• area show a close spatial association to ultramafic metavolcanics. Available analytical data suggest that ultramafic rocks contain significantly higher gold contents than other major rock types. In addition, recent analyses by Keays (1975) suggest that talc-carbonate alteration of ultramafic rocks releases significant quantities of gold. It is proposed that the ultramafic volcanics formed the principal source of gold for the deposits in Timmins, and that the gold was derived from the ultramafic flows when they were extensively carbonatized. Carbonatization of the ultramafic rocks and emplacement of the auriferous quartz-carbonate veins was probably coincident with the last major period of deformation in the gold camp. Delineation of hitherto unrecognized ultramafic volcanics could be an important guide to the discovery of further gold deposits.

Jan 1, 1976

By D. Tetsuka, H. Okamoto

The amount of impurities to be processed in a copper smelting process has increased for recent years because of an increase in the electronic scrap amount. It has been found that Sb and Ni effect on the operation of our copper electrorefining process. It is found that the current efficiency of the copper electrorefining tended to be decreased as the Ni concentration in the electrolyte increased. The passivation of the process seemed to be more related to SO4 concentration in the electrolyte rather than the Ni concentration in it. The current efficiency decreased when the Sb content in the anode was high. A high Sb content in the anode caused easy passivation by forming a gel-like film in the slime layer. We have developed a method to for see the anode passivation in a short time while generating a slime layer. We confirmed the tendency of passivation through the experiment of changing Pb content in anode. Passivation was easily occur with an increase in Pb content in the anode. The amount of slime increased as the Pb content in the anode increased. This suggests that passivation was facilitated because liquid diffusion near the anode was inhibited. INTRODUCTION The amount of impurities to be processed in copper smelting has been growing in recent years because the amount of electronic scrap has increased. Figure 1 shows that the contents of Sb and Ni in copper anodes have increased since 2007.High Sb and Ni contents in the copper anode decreased the current efficiency of the process and made the quality of copper cathode poor because of the anode passivation and the formation of floating slime in the electrolyte during electrorefining. If these influences of impurities are suppressed, it would be possible to make copper electro-refining current density higher and to process much amount of electronic scrap. We examined the components of our copper electro-refining process like anode composition, slime properties and electrolyte composition, and investigated the mechanism by which Sb and Ni affect passivation and current efficiency. When examining the influence of Ni, we noticed that the SO4 important. The effect of SO42 – was also discussed

Jan 1, 2019

By D. H. C. Wilton, W. A. Sears

"Abstract-The 682.8 ± 1.6 Ma Tickle Point Group consists mainly of rhyolite flows and tuffs with- in the Avalon Zone of the Appalachian Orogen in Newfoundland. Stratabound massive sulfide mineralization, consisting of pyrite, sphalerite, chalcopyrite and galena, occurs at the Winter Hill prospect, where a lower pyritic, Cu-rich zone and an upper Zn-Pb-rich zone are hosted by a carbonate-calc-silicate lens. At the Frenchman Head prospect, stringers of pyrite, minor sphalerite, chalcopyrite and rare galena are hosted by felsic volcanic rocks of the Tickle Point Group .Base metal ratios, metal zonations and the overall stratigraphic framework suggest that these sulfide occurrences represent volcanogenic massive to semi-massive sulfide mineralization (stringer type at Frenchman Head). As such these prospects represent the only known VMS occurrences within the Avalon Zone of Newfoundland. Pb isotope data indicate that galena from the Winter Hill prospect is less radiogenic and older than galena from Dunnage Zone occurrences, and suggest that the Winter Hill mineralization formed in an environment tectonically distinct (exotic) from the Dunnage Zone."

Jan 1, 1996

By Staff

"The Weyburn Oil Field, located 80 miles southeast of Regina, Saskatchewan, was discovered by Central-Del Rio Oils Limited, in January, 1955. As of January 1st, 1959, the field had 357 wells capable of producing an estimated total of 45,100 barrels of oil per day.Highly portable, economical, drilling rigs are used to penetrate the pay at a depth of 4,400 to 5,100 feet. Presently, the complete drilling operation for an average field well, including drilling, coring, testing, and running casing, requires 12 days. Drilling procedures are conventional for a field of this depth and no serious problems exist. Central-Del Rio core the productive section of all their wells, which provides valuable information for well completions and reservoir studies. Production casing procedure is to set through the zone and perforate the productive inter-val. This was found advisable due to the lensing nature of the porosity and permeability throughout the reservoir, and to the high connate water saturation encountered in the tighter sections of the reservoir in the north and northeast areas of the field.Although a few wells in the field have produced naturally by flowing or pumping without acid treatment, it has generally been necessary to acidize the wells to make them commercial producers. To date, acid treatments appear to effect better stimulation of the limestone reservoir than fracturing treatments. Perforation sealing balls have been used as an aid in selectively treating all of the perforated interval.The majority of the field is on pump, producing at a low gas-oil ratio. The main part of the field has water-free production, with most of the water being produced in the north and northeastern area. Salt-water disposal is now available in the field through two disposal wells completed in the Basal Blairmore sand.The Midale Beds ""Marly"" and ""Vuggy"" zones form the principal reservoir, which is a stratigraphic trap, with the north and northeast edges terminated by a porosity and permeability pinch-out and the south-west and west edges bounded by water-laden porosity. There is no evidence to date of a gas cap. The reservoir apparently is producing on a fluid-expansion-type mechanism. The increasing water production in wells on the southwest and west edges of the field indicated water encroachment from these directions, and suggests some recovery energy may be available from this source.The total probable ultimate remaining recoverable reserves have been estimated at° 332,469,000 barrels of oil. Markets have not been able to keep up with the rate of development of the medium crude re-serves. However, it is felt strongly that substantial additional markets for Weyburn medium crude will be developed by the producers in the near future at realistic wellhead prices."

Jan 1, 1959

By Jie Li, Xinyu Liu, Yan Chen, Linjian Ma, Yasong Wang

Nonlinear time-dependent response analysis of salt cavern under extreme loads in disaster mode is of great importance to the safety and disaster prevention of gas storage group. Uncontrolled blowout is one of the extreme conditions for compressed-air cavern operation. Based on the geological structure of Jintan salt deposit, China, the numerical model of the complete process of water solution, cyclic operation, and internal pressure runaway was developed. The effects of rapid unloading on the stress filed, the progressive failure of surrounding rock, the volume convergence of storage cavern, and the ground subsidence were simulated employing an elasto-viscoplastic damage constitutive equation for rock salt. The results indicate that the damage and failure zones propagate much larger in the mudstone interlayer than in the host salt. The volume of damage and failure zones surrounding salt cavern induced by unloading process is 5~6 times that of cyclic injection and withdrawal process. The average volume convergence rate of salt cavern reaches 0.012%/d~0.013%/d, which is 6~6.5 times that induced by cyclic operation. The ground subsidence exhibits a typical funnel curve. The affected region of ground subsidence due to rapid unloading in the blowout period is about two times the maximum cavern diameters. Furthermore, double cavern analysis reveals that the interaction between adjacent caverns may be ignored so long as the pillar width is larger than two times the maximum cavern diameters.

Jan 1, 2015

By W A. James

The use of spectrographic semi-quantitative analysis has recently been of considerable value in establishing the geological relationships in a complicated orebody. The principal minerals found in the Mount Pleasant orebody are cassiterite, stannite, sphalerite, molybdenite, wolframite, chalcopyrite and galena, associated with arsenopyrite, pyrite and fluorite. In addition to the large number of minerals, a further com-plication is the non-uniform distribution of the economic minerals, with one mineral being the only one present in major amounts in one area and another mineral being predominant in another area. At the same time, all minerals are present to a minor extent throughout the deposit. This heterogeneity made it advisable to analyse all exploration samples thoroughly. Analysis by conventional means would have resulted in prohibitive costs. By the use of emission spectroscopy, however, it was possible to obtain, quickly and relatively inexpensively, a reasonably comprehensive picture of the orebody un-der investigation.

Jan 1, 1963

By A. McLean, X. Men

"With high quality sulphide ores diminishing, nickel production from low-grade oxide ores becomes increasingly important and a major concern is the high sulphur level in the resultant ferro-alloy. So, desulphurization of the ferronickel becomes an important consideration. Red mud is a waste product of alumina industry and causes adverse effects on environment. In the present study, experiments were conducted to determine feasibility of using red mud as a major ingredient of refining fluxes for ferronickel desulphurization. In view of their influence on slag-metal separation, contact angle measurements between ferronickel alloy and molten slag made from red mud were also determined. INTRODUCTIONNickel is a very important metal that finds a variety of applications including consumer products, building, automotive and electronics. There are two kinds of ores containing nickel, namely oxide and sulphide ores. Anthony and Flett [1] reported that about 55% of the world’s nickel production originates from sulphide ores while the balance of new nickel is derived from oxide ores. However, oxide ores count for about 70% of the worldwide reserves. Apparently, oxide ores will play a significant role in the production of nickel in the future. Most of nickel produced using oxide ores is from pyrometallurgical processes namely ferronickel smelting or matte smelting. So, we can draw such a conclusion that using nickel oxide ores to produce ferronickel will become more and more important .Before used to make stainless steel or other materials, the ferronickel need pretreatment to remove impurities especially sulphur and phosphorus that will cause negative influence on the properties of steel product. Red mud is a by-product during alumina production. Usually, about 1 to 1.5 tons of red mud will be produced when we get 1 ton of alumina. About 90 million tones of red mud are produced every year in the world [2].Red mud is deemed as a toxic industrial waste which needs treatment before discharge because of alkalinity and chemical and mineralogical properties. Until now, the main means to deal with red mud are to store it in impoundments or dump it in the sea depending on local environment. Nowadays, how to recycle red mud has become a pretty hot topic around the world. The last 40 years have witnessed a lot of patent applications concerning the ways of red mud utilization. However, a little amount of red mud is consumed until now due to the limitations of recycling red mud."

Jan 1, 2012

By G. H. Blackwell

Open pit mine management must ensure that sufficient trucks are available and are being used effectively for production, and that operating costs are under continued control and review for improvements. This paper describes methods for estimating truck fleet requirements which have been used effectively at large- and medium-sized open pit mining operations. Applied to commonly available data, multiple regression analyses can indicate when mine plans should be revised toward optimizing the number of trucks required. Prediction of major cost items for budgetary purposes is addressed, along with an example of how readily available production data can be used to reduce costs systematically.

Jan 1, 1999

By C E. Gordon Brown

Aircraft utilization, weather and cost data are given for three separate projects north of the sixtieth parallel in the Northwest Territories and the Yukon Territory. These operations, carried out by helicopter-equipped geological and prospecting parties, have cost $24 to $30 per square mile, depending principally on the distance from the base. They provide adequate surface exploration of areas with 40 to 50 per cent rock outcrop. A good one-inch-to-one-mile geological map can be made. T HE exploration of the Canadian northland has been given increasing attention by the mining industry during recent years. In many cases, the initial problem is to make an adequate reconnaissance of a large area where existing geological information is meagre. The Geological Survey of Canada pioneered the use of helicopter-equipped geological parties for mapping at a scale of eight miles to the inch.

Jan 1, 1964

By Robert A. Brown

"The O'Brien mine is in the west-central part of Cadillac township along the Cadillac 'break', which extends for 7,500 feet from west to east across the property.The ground was staked in 1924 by A. Dumont and W. Hermeston, prospecting for M. J. O'Brien, Limited. The first vein discovered is that now known as No. 1. The No. 4 vein was later exposed on the surface; the other veins known to be present were revealed by underground work and diamond drilling carried out both from the surface and underground.The mine is developed from three vertical shafts: No .. 2 extending from the surface to 2,000 feet; No. 3 from the surface to 1,500 feet; and No. 4 from 2,000 to 3,000 feet. There is on the property a mill of about 200 tons a day capacity, the usual shops, and a townsite housing about forty-five families. Gold production to the end of September, 1944, amounted to 295,824 fine oz. from ore having an average grade of 0.505 oz. a ton. In addition, the mill recovered 3,237 tons of arsenic trioxide having a purity of 83 per cent As2O3.GENERAL GEOLOGYThe four main groups of rocks of the Cadillac area- the Cadillac, Blake River, Kewagama or Pontiac, and Malartic- are found within the boundaries of the property. However, as these rocks have been fully described in · various government reports (1,2,3,4,5,6) and all the known orebodies occur within one group- the Blake River-a detailed description of the geology will be dispensed with here. The known ore deposits lie south of the Cadillac 'break' in a group of rocks that includes 'greenstones', greywackes, conglomerate, porphyries, and a rock of gabbroic composition that may be intrusive. Both flows and tuffs can be recognized in the 'greenstones'. The two bands of porphyry that trend easterly across most of the property have been considered by some observers to be dyke rocks and by others to be flows. Certain evidence points to their being dykes that were intruded as sills considerably prior to the emplacement of the gold-bearing veins, but the possibility of flow origin cannot be fully rejected. North of the talc-chlorite-carbonate schist zone forming the 'break' the rocks are conglomerate and greywacke with iron formation, in which there are no known veins of ore grade. Within the schist zone are minor acid and basic intrusives. The general trend of both bedding and schistosity is a few degrees south of east. The dip is generally vertica1 or steep to the south."

Jan 1, 1954

By John M. Gordon

DURING and after 1949, various groups of British mining engineers came to the Dominion Coal Company, Limited, at Sydney, N .S., to see at first hand the Dosco MINER ( 1). These visits culminated in 1952 with the ordering of four Dosco Miners by the (British) National Coal Board on an experimental basis through their Experimental Expenditure Funds. Others are now on order. The first machine was delivered in February, 1953, and, after slight alterations to suit the different power supply, the machine was made ready to work. Due mainly to the size of the machine, new rules and regulations governing its operation had to be put into effect and it was not until April, 1954, that the machine was put underground. It started to produce in June of that year. The three others were delivered early in 1955. The authors were sent to England by the Dominion Coal Company to install and demonstrate these machines and to work with the Coal Board engineers to- further interest in the machines in the British coal fields .

Jan 1, 1956