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By P. D. S. St. Pierre

IN REGENT YEARS, blast furnace operators have found it necessary to improve their technology in order to handle increasingly low-grade feed and yet satisfy the demands for greater tonnages of metal. Studies have been made covering several aspects of the problem, and in this connection the slags produced in the iron-making process have been critically examined with a view to discovering the slag with the optimum properties for a given operation. A good slag should combine, as far as possible, the properties listed in Table I. Unfortunately, some of these desirable properties are incompatible. For example, the advantage of the small ?bulk of a low-flux slag is offset by its low desulphurization potential and high viscosity. Similarly, a very fluid slag increases refractory wear. It will be seen, then, that a balance must he struck between these conflicting requirements. In the .present paper only the melting relationships of blast furnace slag ?compositions will be considered in detail. In interpreting the data herein presented, the optimum property requirements listed in Table 1 must strictly be borne in mind. It should also be noted that the discussion presented here always relates to calcined fluxes, since this facilitates reference to the final slag composition. Thus, in making calculations pertaining to the ?burdening of the furnace, due allowance should ?be made for the fact that the fluxes are added as carbonates.

Jan 1, 1956

By Wilson Pascheto

One of the main outcomes of a capital project is the reliability of a new plant, system or equipment. During 20 years of experience working in various capital projects for the mining industry, the author experienced failures which have caused significant losses to Owners, in many cases amounting to millions of dollars and almost jeopardizing entire projects. Often, failures were related to faulty design, shop fabrication and/or construction. Therefore, significant opportunities exist in the Mining Industry to improve the success rate of capital projects, improve on-line time at start-up, minimize the occurrence of unplanned maintenance due to equipment failures, and all this with positive contribution to health and safety. This paper presents some examples of failures and how they could have been prevented by proper Quality Assurance methodology. It also discusses some of the main challenges in the implementation of such methodology, including awareness of the Materials discipline and availability of trained Engineers.

Jan 1, 2015

By G. C. Hambleton

"The author has had wide experience in the reclamation of coal from coal mine waste dumps in the United Kingdom.The paper includes such topics as the processing decision and factors affecting processability; method of testing and appraisal; test data interpretation; historical influences in apppraisal; special contaminants and processing difficulties; methods of treatment; review of systems in use and their comparative economics; over-all system economics including excavation, handling methods, recovery system and shale disposal; effluent treatment; environmental considerations; alternatives to processing for coal recovery; light aggregate and cement usage; burned shale heaps; land reclamation; shale deposition for encouragement of vegetation by natural or artificial means; use of tailings fines; the environmental argument for action."

Jan 1, 1972

By L. V. Bell

THE object in prospecting is to find ore. With the exception of certain discoveries of more or less accidental nature, intelligent prospecting as conducted today is, whether consciously or not, based upon a process of elimination. In the following discuss on it is proposed to evaluate those factors that enter into the eliminating of certain tracts of ground and, conyersely, the concentrating of attention upon others. The danger of generalizations as to the barrenness of cer.ain areas, without having due regard for all such factors, is emphasized. The fact that our conception as to what areas or rock formations are to be regarded as favourable or unfavourable is, in some measure at least, changing with new discoveries under diverse and unexpected circumstances, adds more point to the discussion. The criticism might be raised that the subject is treated largely from the standpoint of geology, but that may be met by stating that it is, and must continue to remain, precisely from this standpoint that the prospecror directs his activities. Briefly, the geologist may render the greatest service to the prospector in the early steps of selecting (a) the general territory in which to prospect; (b) the area to be intensively prospected; and, finally, (c) those parts of the claim or claims to be prospected in detail. Although certain phases of the discussion will be, in some measure, of general application, we shall here concern ourselves essentially with prospecting in the pre-Cambrian shield. Furthermore, the subject is so large that it has been decided to limit it to a consideration of that portion of the pre-Cambrian rocks in which is situated the mining district of western Quebec, of which the writer can speak with more personal knowledge. This limitation need not, however, seriously detract from whatever merit the discussion may possess, since the deposits concerned cover a fairly wide range of metallic ores, including gold, copper with associated zinc, and, lastly, molybdenum.

Jan 1, 1936

By Pingchao Ke, Zhihong Liu

Fe(III)-As(V) precipitates were synthesized from the Fe(II)-As(V)-SO42--H2O system at 90°C in initial Fe(II)/As(V) molar ratios of 4.0 and 5.0, respectively. The synthesis were carried out by introducing oxygen gas into the system to oxidize Fe(II) ions into Fe (III) ions, and at the same time, adding aqueous sodium carbonate solution into the system to neutralize the acid released by the hydrolysis reactions, with the purpose of keeping the pH constant at 1.5±0.05. The precipitates obtained were characterized by XRD, chemical composition analysis, SEM, XPS, and Raman spectrum. The results indicated that the particles in the precipitates were in the morphology of irregular aggregation with their sizes in the range of about 1–4 µm. The precipitates consisted of scorodite, ferric arsenate and amorphous hydrated ferric oxide, of which amorphous hydrated ferric oxide formulated as Fe(OH)x(SO42-)y. The characteristic XPS peaks of Fe-AsO43- and Fe-O in the precipitates located at 711.8 and 713.3 eV, separately, and the existence of amorphous hydrated ferric oxide led to two series of shake off lines developed over the end of high binding energy of Fe2p XPS. The precipitates were stable in TCLP tests at pH 4.93 for 60 hours with the arsenic concentrations in the leaching solutions being 0.27 mg/L and 0.59 mg/L for the precipitates prepared in the initial Fe(II)/As(V) molar ratios of 4.0 and 5.0, respectively. The tests for the long-term stability of the precipitates were carried out by leaching them for 40 days at 25°C under various media in the pH range from 9.50 to 10.57, and the results showed that the precipitates synthesized in this study were much more stable than those by previous researchers.

Jan 1, 2017

By M. Mohan Rao

A Sievert ' technique was used. The few determinations made on 10 per cent and 20 per cent V alloys did not show any deviations from Sieverts' law up to I>N2 = 1 atmosphere. The same held true for alloys of 0.2 per cent Ti. Nitrogen absorptions in Fe-Ti alloys, containing from 0.50 to 0.77 per cent Ti at 1,600°C, follow Sieverts' law at low PN2 values, but, due to the formation of a delta titanium nitride phase, deviate from this law beyond critical values of PN2? There is evidence that this phase is Ti1.1N. The behavior observed can be described by the followmg equations: Ti,.,N(o) = 1.7Ti + N K = (fT; ? % Ti)1?7 (f;;.? %~_) = 0.0020 K = fN. %~ = 0.042 '\)-:>N 2 I NTRODUCTJON Nitrogen's solubility in liquid iron-vanadium alloys was investi-gated briefly by Brick and Creevy ( 1), and more extensively by Kash-yap and Parlee (2) and by Pahlke and Elliott (7). Nitrogen's solubility in liquid iron-titanium alloys

Jan 1, 1963

By D. J. Xue

Four kinds of coal-rock combination were subjected to three kinds of stress waves in the SHPB numerical simulation. The wave propagation and the changes of the strain energy in the coal-rock combination during the dynamic impact process were recorded as well as the contact force. The dynamic response law of coal-rock combination was obtained. It was found that the coal had better reflectivity than the rock because of coal with larger impedance. In contrast the rock had better transmissivity. As the crest value of the incident wave increased, the increment in the crest value of the transmitted wave weakened in the coal-coal group, coal-rock group and rock-coal group, in contrast, the increment in the rock-rock group increased.

Aug 1, 2013

The writer presents a concise summary of eleven recent discoveries made in the Maritime Appalachian area, with suggestions for fur the research. This information may prove helpful to geologists working in other fields and to students contemplating further avenues of research in mining geology and exploration. INTRODUCTION THIS paper is not intended as a research study on the subject, but i. merely a brief review of eleven discoveries that have been made in the Canadian Appalachian area. Furthermore, this is not a critical analysis of the merits of any one geophysical method, but it is an un-prejudiced observation of how these discoveries were actually made and what techniques were apparently most fruitful. Some generalizations are attempted whicl1 may suggest further avenues of research in the field of mining exploration. The writer wishes to thank his colleagues in the field for their comments, which he was able to in-corporate into this paper. In particular, he is grateful to Dr. Paul Bevan and

Jan 1, 1963

By L. Cheng, Y. W. Pan, Y. R. Liu

"Impounding deformation of slope and foundation is significant during and post dam construction. Reservoir impoundment is accompanied with various phenomena, including material degradation, effective stress decreasing and buoyancy in rock masses. These phenomena are related with some engineering concerns like reservoir-induced earthquake, landslide and dam stability. The Malpasset dam and Vajont dam are typical hydraulic projects suffering from seepage in dam foundation and slope, which finally led to failure and landslide. Pore pressure in jointed rock masses is considered in constitutive relation. The expression of effective stress for porous rock with fluids is incorporated into the Drucker-Prager criterion. Based on monitoring data of valley width and dam deformation, the effective stress law is applied to analyse the impounding influence of slope and foundation to Jinping-I high arch dam. The dam is accompanied with complicated topographical and geological conditions. The results show that calculated and monitored values agree well, and the application of effective stress law provides an approach to evaluate dam deformation, stress and stability with impounding effect considered.INTRODUCTIONImpounding deformation of slope and foundation is a common and significant problem during dam construction and operation. This phenomenon exists in a lot of reservoirs in China, like Laxiwa, Ertan, Xiluodu and Jinping-I arch dams, and some dams in Europe. It is related with some engineering concerns like reservoir-induced earthquake, landslide and dam stability. The Malpasset dam and Vajont dam are typical hydraulic projects suffering from seepage in dam foundation and slope. Monitored data indicates that the valley width tends to shrink in hydraulic engineering during the impounding process, which will change the stress and deformation of dam and abutment. Therefore, global stability of dam and foundation should be evaluated with impounding process taken into consideration."

Jan 1, 2015

By E. O. T. Simpson

"IntroductionAS COMPARED with coal mines in the United States, and even with some of those in eastern Canada, the coal mines of western Canada, generally speaking, :have made little progress toward mechanization at the working faces. So far as Vancouver island is concerned, there are three main reasons for this : ( 1 ) in some areas, conditions• easy for hand-loading but unsuitable for mechanical loading make high outputs per man •possible by the former method; (2) faulting of the coal seams in ..some areas precludes long-term planning and the introduction and efficient use of expensive equipment; (3) thinness •and other characteristics of the seams in many areas favour hand-loading.No. 8 MINENo. 8 mine of Canadian Collieries (Dunsmuir), Limited, is located in the Cumberland sub-area of the Comox coalfield on Vancouver island about 90 miles west-northwest of Vancouver. The geological structure of this coalfield has been described by J. D. McKenzie. The seams occur in the Comox formation, a subdivision of the Upper Cretaceous Nanaimo Group. The formation is of near-shore origin and was laid down on an irregular surface of' older rocks. The irregular generally have a northeasterly dip, modified by gentile folds and by a •few large, and a number of smaller, faults.Four seams have been worked in the Cumberland area and all vary in thickness and in the amount and number of interstratified bone and rock •bands."

Jan 1, 1953

By E. W. Williams

THE Ontario Research Foundation has developed a process for producing low-density steel shapes by direct reduction of iron oxide powders. The process is a combination of reduction, sintering (without compaction), and carburizing, and has been described by Cavanagh (1). Iron oxide powder, in the form of mill scale or highly concentrated iron ore, carefully sized, is poured into a porous mould. A reducing agent, generally coke breeze, is placed around this mould in a heat resistant sagger which is sealed off and heated to 2,000°F. for a number of hours. The coke/ ore ratio, the particle size distribution, the temperature and time of soaking, and the size and shape of the reduced product, determine the densities and carbon contents attained. The Defence Research Board sponsored a programme of research into some of the mechanical properties of the material (which was named Controlled Density Steel) and this paper is an account of various factors which govern the tensile strength of the steel. The ?practically attainable range of density is from 1.5 to 5.5 gm./ cc. but higher densities are obtained on hot working. This paper, however, is restricted to discussion of results for moulded products.

Jan 1, 1957

By Jarrett. K. M.

Nobody has, as yet, made a perfect machine. Therefore, when a machine is operating and functioning as it is designed to do, there is always some vibration present. This is easily and simply measurable with present-day equipment and any increase in the amount of vibration will indicate a potential failure. When an increase is noted, vibration analysis can pinpoint the cause of the potential failure and remedial action can be taken before an unscheduled shutdown is necessary or a breakdown occurs.

Jan 1, 1972

By Martin Junker

This Notwithstanding all the debates on climate change and renewable energy, coal remains the world's no.1 primary energy source even in the 21st century. In 2011 alone, total output rose from 420 million t to around 6.6 billion t. Similar growth rates are also expected for the next few years. In order to meet demand, new seams are being tapped and others mined far more extensively. In most cases, this means a move from open-cast to deep mining, and extracting coal from ever greater depths. At the same time, extraction processes such as the room and pillar method are being replaced by longwall mining, which significantly increases seam yield and therefore output. The depth of extraction with new, modified mining methods is increasing rapidly around the world - in most countries, much more rapidly than the corresponding expertise. A trade in mining expertise has therefore developed alongside the coal trade proper. Germany relies on coal imports, but can export mining industry services and advanced mining equipment. Geological conditions in the Ruhr and Saar coalfields forced Germany to drive forward development of deep working for hard coal years ago. For 30 years now, Germany has been mining hard coal at depths of over 1,000 m, and excavation is now at depths up to 1,600 m. Deeper extraction and more extensive excavation posed new challenges for both miners and equipment. Intelligent logistics, modern roadway development methods and longwall mining with ploughs or shearers combined with optimised process coordination offered pioneering solutions - solutions to enable costeffective coal extraction in the long term without compromising safety. Countries such as Russia, the Ukraine, China and the Czech Republic, where extraction is now reaching similar depths, can now benefit from this experience: they do not need to go through the same process of trial and development, but can draw on Germany's findings and ultimately save on costs. Now, Germany is offering this knowledge and experience on the international market on a client- and deposit-specific basis to continue providing mining countries with safe and cost-effective coal mining solutions and secure the energy supply. The presentation gives a number of examples of how international mining companies have used expertise from Germany to better meet the challenges of deep mining.

Aug 1, 2013

By S. R. McCutcheon, D. R. Lentz

"Abstract - The 12.1 Mt Brunswick No. 6 Zn-Pb-Cu-Ag massive sulfide deposit (New Brunswick, Canada) lies between two subaqueous felsic volcanic formations near the base of the Middle Ordovician Tetagouche Group. The footwall comprises rhyodacitic pyroclastic rocks (Nepisiguit Falls Formation), whereas the hanging wall comprises a sequence of rhyolitic flows, breccias, and hyaloclastites (Flat Landing Brook Formation), with an age difference of less than 3 m.y. The Brunswick No. 6 deposit is a proximal autochthonous deposit with a well-zoned massive sulfide body and a basal Cu zone that, at depth, develops into a stockwork stringer sulfide (feeder) system. The massive sulfides are capped sharply by a layered magnetite-chert unit that extends regionally beyond the deposit. The deposit has a keel shape (sheath) formed by the F1F2 interference pattern. The heterogeneous ductile deformation and upper greenschist-grade regional metamorphism has transposed many of the epigenetic stockwork structures and alteration within the host sequence. Hydrothermal alteration is much more extensive, both vertically and laterally, in the footwall (a few 100 m) than in the hanging wall (<100 m). Anomalies farther up in the hanging wall sequence seem to be associated with independent alteration systems related to the rhyolite domes. The least-altered footwall units exhibit keratophyric alteration (albite or adularia) and weak Mg enrichment (chlorite). More intense micaceous (sericite and Mg-rich chlorite) alteration occurs around the footwall sequence. The transposed stockwork stringer sulfides are typically composed of Fe-rich chlorite (± sericite, ± silica) with pyrite, pyrrhotite, chalcopyrite, arsenopyrite, and sphalerite. The (Fe2O3T+MgO)/(Na2O+K2O) and base metal alteration indices are the best practical lithogeochemical vectoring tools at this deposit. Sommaire - Le gîte de 12.1 Mt de sulfures massifs de Zn-Pb-Cu-Ag Brunswick No.6 est localisé entre deux formations volcaniques felsiques sous-marines situées près de la base du Groupe de Tetagouche d’âge Ordovicien Moyen. Le mur consiste en roches pyroclastiques rhyodacitiques (Formation de Nepisiguit Falls) tandis que le toit consiste en une séquence de coulées, de brèches et d’hyaloclastites de composition rhyolitique (Formation de Flat Landing Brook); la différence d’âge entre les deux est de moins de 3 m.y. Le gisement Brunswick No. 6 est un gîte autochtone proximal comprenant un corps de sulfures massifs clairement zoné ainsi qu’une zone cuprifère basale qui passe progressivement à un stockwork de filonnets de sulfure en profondeur (feeder). Les sulfures massifs sont abruptement surmontés d’une unité laminaire de chert et de magnétite dont l’extension par delà le gisement est régionale. Le gisement affecte la forme d’une quille (fourreau) résultant d’un patron d’interférence F1F2. Plusieurs des structures épigénétiques du stockwork et des patrons d’altération de l’encaissant ont été transposés par la déformation ductile hétérogène ainsi que par le métamorphisme régional au faciès des schistes verts. L’altération hydrothermale est beaucoup plus importante, tant verticalement qu’horizontalement, dans le mur (quelques 100 m) que dans le toit (<100 m). Les anomalies situées plus haut dans le mur semblent être reliées à des systèmes d’altération indépendants associés aux dômes de rhyolite. Les unités les moins altérées du mur une altération kératophyrique (en albite ou en adulaire) ainsi qu’un faible enrichissement en Mg (chlorite). Une altération en mica (séricite et chlorite magnésienne) plus intense est présente autour de la séquence du mur. Les sulfures du stockwork de filonnets transposés consistent typiquement en chlorite ferrifère (± séricite, ± silice) accompagnée de pyrite, de pyrrhotite, de chalcopyrite, d’arsénopyrite et de sphalérite. L’indice d’altération (Fe2O3T+MgO)/(Na2O+K2O) et l’indice des métaux usuels sont les outils d’exploration les plus appropriés dans ce gisement."

Jan 1, 2006

Pilot plants for pressure hydrometallurgy represent special design and project execution challenges unique to the industry and to the pilot- and demonstration-scale. Pilot plant projects have different objectives and shorter timescales than commercial plant projects. Design considerations and strategies, and project execution methods that meet the special needs of pilot plant projects, are discussed. Specific guidance is given for the selection of appropriate pressure and temperature design points for pressure hydrometallurgical process equipment, and for the selection of materials of construction for pilot-scale equipment. The balance between the need for process similarity with future commercial operations and the realities of pilot-scale equipment is also discussed.

Jan 1, 2004

As land resources decrease, commodity prices increase, and technology evolves, deep sea mining is becoming a viable alternative to meet the increasing demand for minerals. Successful deep sea mining operations are built on sound identification of the resource, proper selection of equipment, a thoughtful production plan, and good project management. These four key activities can be further optimized by analyzing how the spatial variability and uncertainty of the ore body properties impact the final mining operation. To address this problem, IHC Merwede is in the process of developing a risk quantification framework in the context of deep sea mining, which makes use of state of the art geostatistical simulation methods and transfer functions to quantify geological uncertainty and translate it into decision or project risk. The paper introduces the Local Average Subdivision method (LAS) for generating simulated models of the deposit and presents a new extension to incorporate point measurements of geotechnical or ore grade properties. Due to its computational efficiency, the presented method is suitable for simulating largely extended sea floor deposits. The second part of the paper illustrates, through example case studies, the significant benefits of a risk based approach which translates geological uncertainty into financial or operational performance indicators. In particular, the focus is on assessing financial project risk and on the design optimization of the deep sea excavation equipment by analyzing cutting forces, specific energies, and power requirements.

Aug 1, 2013

By R. A. Brown

RIGHT NOW the Canadian oil business is suffering from growing pains brought on by developments outside our borders. I would like, therefore, to place our industry in perspective for you in two ways. I would like first to describe it briefly and let you see it in relation to the world oil industry. Then I would like to bring it back and place it into perspective against a strictly Canadian background. Naturally, in such a discussion, it is necessary to use a certain amount of statistical material. I&apos;ll endeavour, however, to keep it to a minimum. Eleven years ago, before the discovery of Leduc, Alberta could boast of having 21,000,000 barrels of crude oil reserves. Five years ago we had 1,810,000,000 barrels. At year end, 1957, our remaining recoverable reserves totalled more than 3,000,000,000 barrels. In 1957, our potential production in Alberta reached an all-time high of 756,000 barrels a day. Unfortunately, our actual average daily production dropped from 393,000 barrels per day in 1956 to 376,000 barrels per day in 1957. And in 1958, to date, it has dropped sharply to around 300,000 barrels per day.

Jan 1, 1958

By John A. Hansuld

Geochemical dispersion of metals under various environmental conditions is discussed within the frame-work of Eh (oxidation potential) and pH (acidity). In general, two aspects are considered -(1) the oxidation of certain primary sulphides in the outcrop or sub-outcrop environment, and (2) the movement of metals in different dispersion media. Practical applications of each are illustrated by means of exploration case histories representing environmental conditions in the Canadian Shield, the southwestern United States and the Caribbean.

Jan 1, 1966

By Hani Henein

Most metals and alloys processed undergo a solidification processing step. Increasingly, there is a growing number of solidification processing routes that involve rapid solidification of the alloy. These include strip casting, high pressure die casting, 3D printing, and atomization for the production of powders or spray formed parts. By contrast, there are few experimental techniques developed to study the solidification path of alloys during rapid solidification. Amongst these laser melting and solidification, Electromagnetic Levitation (EML) and Impulse Atomization (IA) are the most prominent. Of relevance is the formulation of the solidification path of an alloy and the resultant identification and quantification of metastable phases and their relationship to processing conditions. This typically involves the understanding of the interplay between undercooling and cooling rate for the various phases that form. This presentation will outline some of the methodologies developed to quantify phase fractions and their solidification path as a function of processing conditions using EML and IA.

Jan 1, 2016

By A. Jain

During sheet forming, metal experiences not only multi-axial load, it also undergoes strain path changes. For example, metal in the flange region may be drawn, may bend and unbend through a bead, before bending around a die radius, etc. Compression data were obtained from AZ31 sheet after pre-straining in compression along an orthogonal direction. The compression directions correspond to the sheet product (rolling-RD, transverse-TD, and normal-ND) directions. Three cases are examined: slip dominated deformation (ND) followed by twin dominated (RD or TD) deformation, twin dominated (RD or TD) followed by de-twinning (ND), and twin dominated (e.g. RD) followed by cross-twinning or secondary twinning (e.g. TD). Slip induced pre-straining simply hardens the material, while twin dominated pre-straining alters the texture allowing the material to either de-twin or re-twin upon changing the strain path. Polycrystal plasticity modeling has been used to predict qualitative features of the flow curves during strain path changes.

Jan 1, 2006