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By Güney

"An investigation carried out to determine the tendency of coals to heat spontaneously in terms of time-temperature curves coupled with the resulting oxidation products in an adiabatically controlled laboratory setup is described. Tests were made at differing moisture conditions, including oxidation and also oxidation with either adsorption or desorption of water vapour on coal.From the experimental evidence, there is reason to believe that the oxidation of coal, although an important factor, is not the predominant one in the development of spontaneous heating. In addition to the temperature increase in coal and the gaseous products evolved due to auto-oxidation, the process is accelerated by adsorption and retarded by desorption of water vapour on coal."

Jan 1, 1971

By I. Ruiz Bustinza, L. F. Verdeja, Daniel Sbarbaro, R. Parra, J. Mochón

The oxidation of sulfides is a complex process involving gaseous products and intermediate species given rise to emission and absorption spectra which carry out important information about the reaction process. This information could be used for on line monitoring of pyrometallurgical reactor if the appropriate sensors were available. We present in this paper an analysis of the concept that has been successfully applied in iron and steel making industry, as well on fuel combustion control, where the spectra measurement gives the possibility for online monitoring and automatic control of high temperature processes. This concept has not been widely applied in the nonferrous pyrometallurgical primary production. The design of new sensors is discussed from the analysis of spectra measurements during flash combustion of copper concentrates at laboratory scale.

Jan 1, 2015

By F. A. McLean

At the Annual Western Meeting held at Blairmore, Alta., October 1924, the writer presented a paper drawing attention -to the advantages of portable gas-driven equipment for developing isolated mining properties. This type of equipment was at that time practically in its infancy and the details of results actually accomplished were somewhat meagre. During the last year or so a number of these plants have been installed so that it is now possible to offer more definite information regarding the actual mining progress accomplished with such plants and their cost of operation in various parts of the country. This paper has been written with the idea of reviewing the work done during the past year, and to supply data which may be of interest to those wh9 are confronted with the problem of selecting equipment for development or assessment work. Because drilling operations play such an important part in mining, one of the first problems that usually confront the prospective? mine owner is the selection of the proper com-pressed-air plant. The size and type of equipment and the method of driving it require careful consideration. The size and type of equipment is determined largely by the funds available, transportation facilities, and the speed with which the programme of development is to be carried out. The selection of the proper method of drive usually depends on local conditions, such as the relative cost of various fuels, and has an important bearing on operating costs.

Jan 1, 1926

By W. A. Haley

This paper discusses how a large wheel loader should be equipped, with particular attention paid to tires and tread life, and describes the several steps that can be taken to provide favorable working conditions and reduce over-all costs. A comparison is then made of wheel loader production and costs vs those of power shovels, and the present and possible future applications of the wheel loader are outlined.

Jan 1, 1969

By X. Q. Jiang, D. L. Chen, A. Macwan

Magnesium alloy, being the lightest structural material, is a key candidate for the weight reduction of vehicles in automotive and aerospace industries; however, its poor corrosion resistance and difficulty in deformation are limiting factors. Recently, Al/Mg/Al tri-layered clad sheets have been considered as a promising alternative to improve corrosion resistance and formability of magnesium alloys. The aim of this study was to evaluate the tensile properties and deformation behavior of Al/Mg/Al tri-layer clad sheets at different temperatures and strain rates. Yield strength (YS), ultimate tensile strength (UTS), and elongation were observed to increase with increasing strain rate. With increasing temperature from -40°C to 180°C, YS and UTS decreased and ductility increased. The strain hardening exponent evaluated via three equations of Hollomon, Swift, and Afrin et al. showed a similar increase with increasing strain rate and decreasing temperature. The fractographic analysis showed partial debonding of clad interface especially at higher strain rates and lower temperatures.

Jan 1, 2015

By F. R. Jones, B. W. Taylor, A. R. MacPherson, L. J. Lamb

"The Lake St. Joseph Iron Deposit is in Northwestern Ontario. Exploration to date by Steep Rock Iron Mines Limited has indicated an ore reserve of 683 million long tons. Metallurgical investigations have proved that suitable oxide pellets and/or superconcentrates can be economically produced from this ore. Studies of the Lake St. Joseph iron ore deposits have covered the period 1956-71, and have embodied applications of the improvement in mining and processing technology over this period. Market demand in the early 1960's for high-grade oxide pellets as a replacement for natural iron ores for the blast furnace first drew attention to the potential of the Lake St. Joseph deposit. The current market trend toward utilization of sponge iron to replace steel scrap as feed to electric furnaces and cupolas now suggests that the deposit can better be exploited as a prime source of superconcentrates."

Jan 1, 1972

A newly developed damage model was used in the study of rock fragmentation mechanisms involved in crater blasting. Simulations show that at the detonation of the explosive charge, a crushed zone around the explosive charge is formed due to compressive failure and then a strong pressure wave is sent out forming a pressurized ring that propagates at the dilatation wave velocity. As the pressurized ring leaves the crushed zone, two tensile stress components perpendicular to the radial stress are developed in response to the action of the radial pressure, causing tensile failure and forming a damage zone around the charge. The formation of this damage zone is quite independent of the depth of the explosive charge provided there is no interference by the reflection from the free face. When the pressurized ring reaches the free face, it is reflected there and causes rock failure on the ground surface that forms another damage zone. Under the simulation conditions, it is revealed that the depth of charge is a factor controlling the relationship between the two damage zones. At a depth smaller than the optimum, the two damage zones coalesce into one and there is excessive rock breakage; otherwise, the two damage zones tend to isolate from each other with the increase in the depth of charge. Calculations of fragmentation indicate that the average fragment size increases and the uniformity of fragments decreases when the depth of charge increases as observed in practical blasting.

Jan 1, 1998

By Max W. Ball

THE world's largest known oil deposit lies in northern Alberta. In fact, according to government estimates, the famous so-called 'tar sands' of the Athabaska region contain several times as much oil as all the other proved reserves of the world. S. C. Ells, of the Department of Mines and Resources, who has been the Dominion Government's authority on the oil sands since 1913, has estimated the minimum content of the deposits at 100 billion barrels(!). C. P. Bowie, of the U.S. Bureau of Mines, has published an estimate of 250 billion barrels(2). ?In comparison, the latest authoritative estimate of the proved oil-field reserves of the world is less than 35 billion barrels(3). Out of this tremendous total, perhaps 500 million barrels are commercially available at present-day costs and prices; the remainder must be considered a latent reserve to be used when development costs are materially lower and petroleum prices materially higher than they now are. Mean-while, the 500-million-barrel portion presently available contains more oil than has been found in all the rest of Canada, and constitutes one of Canada's great mineral resources. Although these deposits have been known to white men since 1788, when Peter Pond, the explorer, found the Indians stewing the oil out of the sand and mixing it with spruce pitch to caulk their canoes, they are only now coming into commercial production. The purpose of the present paper is to describe the deposits, their oil content, their present development, and the possibilities that seem to lie immediately ahead. For the sake of completeness and clarity, the writer has not hesitated to use or to paraphrase material that he has previously published elsewhere in discussing various aspects of the oil sands.

Jan 1, 1941

By B. Yu, S. Kelebek, C. Gibson, M. Aghamirian

There are a number of high grade niobium deposits worldwide which have been deemed untreatable by flotation due to the very fine grained nature of the in situ pyrochlore, the primary niobium bearing mineral. A known method of recovering extremely fine particles is through the use of chelating reagents such as hydroxamic acids which have a strong affinity for transition metals. However, one of the major issues in the flotation of niobium bearing minerals using hydroxamic acids is the corresponding recovery of other transition metal gangue minerals including magnetite, hematite, and pyrite. In order to better understand the differences in behavior of niobium and iron bearing minerals in flotation with benzohydroxamic acid (BHA) and sodium hexametaphosphate (SHMP) at a range of pulp temperatures, a Box-Behnken experimental design was employed. Regression models for the global recovery of iron indicated that iron mineral recovery was significantly influenced by both BHA and SHMP dosage. Upon examinination of flotation products by semi-quantitative XRD, it was observed that recovery of iron oxide and sulphide minerals (hematite, magnetite, goethite, and pyrite) was problematic at high benzohydroxamic acid dosage, while sodium hexametaphosphate was mainly helpful for carbonate mineral depression. Iron rich carbonates (likely an iron rich dolomite) largely reported to the tails with increased SHMP dosage.

Jan 1, 2015

By A. J. Monhemius

This paper reviews the history of modern iron-control processes in hydrometallurgy. Attention is paid to processes developed in the electrolytic zinc industry for removal of iron from zinc sulfate leach liquors and the problems faced by the industry in the safe disposal of the iron residues produced by these processes. Past lessons learned are projected onto current efforts to develop hydrometallurgical processes for treatment of copper sulfide concentrates. It is argued that any attempt to create a \u201chydrometallurgical copper smelter\u201d will fail, unless methods are developed that can recover iron in a form that can be directly used by the steel or pigment industries.

Jan 1, 2017

By C. Jay Hodgson, P. J. MacGeehan

"The gold ore zones of the Campbell and Dickenson mines occur within a km-wide, 2 km-long zone of highly altered and anomalously fissile and deformed volcanic and subvolcanic intrusive rocks, cut by a series of mainly post-deformation mafic and quartz-feldspar porphyry felsic dykes.Three main periods of gold ore-forming hydrothermal activity are recognized. In the first, the mine rocks were extensively altered and gold and arsenic enriched; syn-volcanic auriferous veinlet and low-grade chemical sedimentary ores were deposited in what was a major discharge zone of a submarine hydrothermal system. The chemical sedimentary ores are closely associated spatially and temporally with domal rhyolitic extrusions. Because of its mechanical and chemical properties, this synvolcanic alteration zone became the locus of later deformation, and the site of the generation of auriferous hydrothermal solutions, perhaps by pressure solution processes at depth. These solutions deposited, synchronously with deformation and metamorphism, the second and most economically important type of ore zones in the mine: large foliation-parallel and foliation-oblique banded carbonate- 'chert' Rssure-filling veins.In the third and final mineralizing event, high-grade, pipeshaped zones of siliceous replacement-type mineralization, and quartz-arsenopyrite-gold veins, were superimposed on the previous mineralization types after most of the deformation, but before the emplacement of the late dykes. The source of heat and also possibly the fluids for the third mineralizing period may have been the dyke-forming igneous activity. The textures and mineralogy of the banded carbonate- 'chert' veins suggest a near-surface (<3 km) environment of deposition, but their relationship to the fabric of their host rocks indicates they were emplaced in an environment, presumably at considerable depth (5-10 km?), in which the rocks were undergoing intense penetrative deformation. This anomaly is unresolved."

Jan 1, 1982

By Neil Campbell

"The gently-dipping Devonian dolomite beds south of Great Slave lake in northern Canada are nearly every-where concealed by a cover of glacial drift and muskeg. Nevertheless, in 1898 or earlier, four small outcropping areas of dolomite, richly mineralized with lead and zinc sulphides, were discovered. Exploration work performed here up to the end of 1930, included intensive trenching and drilling of the showings, together with mapping and wide-spaced drilling in the surrounding region. This work proved that the discoveries are isolated pockets of mineralization much too small to be commercially valuable by themselves. No evidence of orebodies elsewhere was reported.Meanwhile, mapping by the G.S.C. in the Shield far to the east disclosed major Precambrian faults, some of which can be projected southwesterly (under a cover of Paleozoic sediments) to the vicinity of Pine Point. During the period from 1940 to 1947, consideration was given, by The Consolidated Mining and Smelting Company Ltd., to evidence of a theoretical possibility that, although apparently dormant in Paleozoic times, these faults may have provided a structural control and a source of ore-bearing solutions in some post-Devonian period. From this, it was postulated that the breaks might have created, in the overlying dolomite, a linear array of orebodies concealed by overburden but lying in a belt of considerable length and in a position predictable within practical limits. A program of drilling designed to test and exploit this specific concept was conducted from 1948 to 1955.he drilling within the new, theoretically-defined search area resulted in the discovery of many lead-zinc ore-bodies, none of which was exposed at the surface. Some of these are large and (as indicated by 1965 production records) very rich. They are situated 1 to several miles distant from, and apparently not connected to, the earlier-known surface discoveries. The drilling also disclosed that the ore, which consists of disseminated sphalerite and galena replacements together with colloform sphalerite and coarse galena cavity fillings, occurs mainly at certain stratigraphic horizons within a large, coarsely-recrystallized dolomite barrier reef. Considerable fracturing and folding was found. It has been suggested that reef development was influenced by post-Precambrian tectonic movements associated with the old faults in the basement complex. The ore may have been deposited by solutions moving from distant sources to favourable structural and chemical environments in or related to the reef.In more recent exploration performed in the course of preparing for mining production, the rate of ore discovery within the same general geological context has been greatly accelerated by the use of new geophysical techniques and drilling equipment. Reserves of 21.5 million tons, averaging 4 per cent lead and 7.2 per cent zinc, were reported in 1965, and production from open pits at the rate of approximately 248,000 tons of concentrates per year is in progress"

Jan 1, 1966

"Real time analysis of conveyed bulk materials can be used to improve process performance by reducing variability and upgrading ore quality through selective removal of increments of flow that do not meet appropriate selection criteria. This paper focusses on proven Prompt Gamma Neutron Activation Analysis (PGNAA) and microwave transmission technologies used to representatively measure conveyed ore quality in real time so that meaningful decisions can be made between the mine and mill. This enables the effective removal by bulk diversion of small increments of conveyed flow such as waste, highly deleterious material or sub-economic material from the mill feed. Improved ore quality in plant feed optimises process performance, reduces processing costs and minimises tailings generation. Analysis is unaffected by particle size, dust, layering or segregation, mineralogy and belt speed. Technologies are explained and performance examples given from installations in copper and iron ore. The technology has been used successfully in bulk sorting for over twenty years typically using measured increments of a few minutes. Improvements in technology and calibration performance have resulted in accurate measurements over increments of thirty seconds and below.INTRODUCTION Ore quality variability exists on a number of scales. Block model grades represent a few hundred to many thousands of tonnes. Grade control at the mine occurs on a scale typically down to the size of a haul truck, which may be a few hundred tonnes. Highly variable ore quality is detrimental to process efficiency and effectiveness. Processing waste or low grade ore when higher quality feed is available represents a lost opportunity to generate higher revenues earlier in the operational life. Measuring ore quality accurately over short time increments during conveying enables small increments to be measured and diverted according to their quality. The paper explains the technology and benefits. Neutron irradiation techniques were considered potentially suitable for conveyed bauxite measurement by Beurton et al, 1995. Tran & Evans (2001) concluded there was no equivalent technology to Prompt Gamma Neutron Activation Analysis (PGNAA) in terms of material penetration power. PGNAA was evaluated by Nelson & Riddle (2003) for possible use in the phosphate industry and recommended its use for further characterisation of the mine’s various ore types to improve stockpile allocation and grade control. Cottle (2007) discussed test work for an iron sinter application and Delwig et al (2011) described the successful installation in 2009 and performance of PGNAA for base-to-acid ratio control in sinter feed with the analyser output used to control lime addition. Geoscan (PGNAA) works very well on iron ore and can “improve control over what is happening in the plant” and that comfort can be provided in knowing that the product is on-spec according to Minnett (2010). PGNAA is not yet used in the minerals sector for tariff purposes as has occurred since 2000 with Coalscan (PGNAA) in coal (Minnett, 2010)."

Jan 1, 2017

By M. F. Goudge

ROCK wool, one of the most recent additions to the list of Canadian-made, insulating materials, is a soft, light, fibrous material consisting of interlaced, flexible, glassy fibres so exceedingly fine that, individually, they are almost invisible to the naked eye and will float in air. In the process of manufacture, a suitable rock, generally a self-fluxing argillaceous dolomite consisting of nearly equal proportions of acidic and basic constituents, is melted to a completely fluid state and then converted into fibres either by a blast of steam or air, or by a mechanical device. The increase within the past five years in the number of plants in the United States making rock wool and slag wool has been remarkable, especially in view of the depressed conditions prevailing &apos;with most industries during this period. In 1930, there were only 8 plants reporting production of .these materials, whereas at the present time there are 44 plants in the United States listed as making these products, and there are 3 plants in Canada. In 1929, the total sales of rock-wool products in the United States amounted to-$2,377,324. In 1934, according to the National Rock and Slag Wool Association, 26 member companies reported sales of $3,695,405, and in 1935 the sale&apos;s of 30 member companies had a value of $5,571,469. The establishment of the rock-wool industry in Canada followed the publication in 1931 of a report (1) by the Mines Branch, Department of Mines, Ottawa, in which was set forth the results of field work and laboratory studies which indicated that large deposits of rock in the Niagara peninsula, hitherto regarded as valueless, were suitable for the making of rock wool. This report was supplemented in 1934 by another report (2), giving the results of further laboratory and commercial-scale tests on the rock from these particular deposits, which proved conclusively that rock wool of good quality could be made from the rock in question.

Jan 1, 1936

By R. C. A. Thurston

"The lack of notch ductility in structural steel in general, and in ship plate in particular, has been the object of widespread attention in the metallurgical world since the spectacular collapse of the ill-fated S.S. Schenectady in 1943. Numerous investigations have been carried out, many new tests have been developed, and a vast amount of useful data has been published, with the result that our knowledge is now far more advanced than it was at the time of this disaster. Interest has focused largely on the medium strength steels, and the various factors which cause a normally ductile steel to behave in a brittle manner in the presence of a notch and at relatively .low temperatures have been thoroughly studied.The literature available on high-tensile steels, however, is less extensive and the present paper is intended to supplement this information. Notch toughness tests have been carried out, at the request of the R.C.N., on a high-tensile manganese steel in the form of commercial ship plate. One of the newer tests, the tear test, and the Charpy V-notch impact test, were used to examine the characteristics of plate for the construction of an ice-breaker. About 250 plates, mainly in the thickness range from 11,4 in. to 1 % in., were tested. An an-alysis of the results obtained is presented, certain aspects of the tear test are discussed, and the correlation between the two types of test is studied. On the basis of information available from casualty ships, the plates, with few exceptions, were considered to be satisfactory."

Jan 1, 1959

By C. D. Rowe, H. S. Mitri, J. Malki, I. Vennes

Ore extraction at great depths creates high stresses around mine openings, which can result in violent rock failure in one of various forms of strainburst. This is especially true with strong and brittle rocks, which can store a large amount of strain energy that is suddenly released at failure. The strength and brittleness of rocks have been extensively investigated in the past. The most widely accepted method for the determination of rock burstability is the strain energy storage index obtained from a non-destructive uniaxial load–unload test. However, the results of this method are not always conclusive, showing less repeatability when the target test load is changed. This study concerns itself with the introduction of microscopic analysis as a tool to help validate the strain energy index results when burstability cannot be warranted based on mechanical property tests alone. In this study, two types of rocks, namely, basaltic komatiite (BK) and felsic norite (FNOR) obtained from Canadian underground mines are examined. The selection is based on the premise that felsic norite is known to be burstable from the mine experience, whereas basaltic komatiite is not necessarily burstable. A total of 60 mechanical properties tests were conducted including uniaxial compressive strength, Brazilian tensile strength, and load-unload tests. Laboratory tests on FNOR consistently exhibit high burstability; however, the results for the BK tests are not conclusive. To seek explanations for the mechanical rock behavior, 18 thin sections were examined with optical microscopy and image analysis. The findings show the tested BK specimens are dominated by alteration products, and all primary igneous minerals are lost. There is minor quartz, garnet, carbonate minerals, talc, and serpentine, which give the rock its ductile properties. The FNOR specimens are found to be relatively fresh and supported by a strong network of plagioclase with minor pyroxene, biotite, and secondary micas, explaining the higher stiffness. This study demonstrates how optical microscopy can complement mechanical property tests to evaluate burstability of rocks.

May 4, 2025

By Habib Zughbi, Paul Zulli

"A key step towards sustainability in iron and steelmaking is to optimise the use of raw materials and energy consumption, and consequently minimise CO2 emissions. Models based on a Process Integration (PI) approach play a key role in evaluating various scenarios and the impact of introducing changes in raw materials and operational conditions on the overall energy consumption and CO2 emissions. BlueScope uses a PI based comprehensive model for its Port Kembla Steelworks (PKSW), called the Integrated Steelworks Energy and Emissions Model (ISEEM). ISEEM is tightly coupled to the configuration of PKSW. It is based on mass and energy balances as well as thermodynamic relationships. ISEEM is a steady-state model and is used to predict overall and detailed unit-by-unit energy consumptions and CO2 emissions. It is also used for plant-based scenario modelling. This paper investigates the impact of major changes to PKSW configuration, including the shutting down of a blast furnace and cokemaking battery, on the energy consumption and CO2 emissions of the plant. It discusses some of the issues involved in updating the model and some identified opportunities."

Jan 1, 2015

By A. J. Miller

Estimates of interstitial water saturation derived from capillary pres-sure data are compared with residual water saturations found by the analysis of cores out in oil-base drilling fluid. A theoretical explanation for the high-rate of water production from the Bellshill Lake Field is proposed, based on the interpretation of the capillary pressure data.

Jan 1, 1960

By M. Bryson, S. Broom-Fendley, A. E. Brady, W. Dawes, G. Beer, N. Sehlotho, S. Al-Ali, F. Wall

The Songwe Hill Rare Earth Element (REE) Project in Malawi is a near surface carbonatite-hosted deposit with synchysite and apatite as the key REE bearing minerals. A strong focus has been placed on understanding the REE mineralogy of the Songwe Hill carbonatite as REE mineralogical characterization is a crucial component at all steps, ranging from exploration to production, in the development of REE deposits. Extensive mineralogical work has been completed at Camborne School of Mines (CSM), Natural History Museum (NHM) London, British Geological Survey (BGS), Nottingham, Aberystwyth University, Wales, Mintek, South Africa, and SGS Inc. Canada (SGS). The following analytical techniques were used: scanning electron microscopy (SEM), electron microprobe analysis (EMPA), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and QEMSCAN®. The detailed studies have demonstrated that while synchysite is light-REE enriched as expected, apatite, abundant in all stages of carbonatite emplacement at Songwe, is anomalously enriched in mid- to heavy-REE relative to apatite in other carbonatite deposits. The distribution of REE within synchysite and apatite at Songwe has had important implications for the direction of the metallurgical work with respect to the behaviour of light and heavy REE through the flotation and hydrometallurgical stages of the flow sheet.

Jan 1, 2014

By H. W. Parsons

Several low-temperature, dry chlorination processes for the treatment of sulphide minerals are reviewed, in a chronological order. These processes include the following: the Swinburne-Ashcroft, Baker-Burwell, Maim, Comstock-Wescott (Aldermac) and the Mitterburg Mining Process. Dry chlorination investigations at the Canadian Mines Branch (now CANMET) and the U.S. Bureau of Mines are discussed, as is a proposed process by the South Africa National Institute for Metallurgy. The techniques used in the process are discussed, as are the shortcomings, problems and failures of the methods.

Jan 1, 1978