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By N. M. Stubina, P. J. Lind

Barrick Gold is in the process of building several new mines and implementing new processes at existing mines for which metallurgical technology is of key importance. The roles of the company's Strategic Technology Solutions team and the Barrick Technology Centre are discussed within the context of their responsibilities within Barrick's Operations Support group. The paper will present an overview of the development of the technology centre from the former Placer Dome Research Centre to its current form supporting strategic technology, capital projects, and operating sites. Novel approaches to research and development will be presented as well as an overview of some of the technologies developed from bench-scale to pilot-scale, and beyond.

Jan 1, 2011

By R. S. Jones

"Fording Coal Ltd. is now in its fifth year of a 15-year contract to supply 3 million long tons of clean coal per annum to its Japanese steel-making customers. The mine employs both conventional truck-shovel and unconventional ""walking"" dragline coal mining techniques in multiple-seam pits. This paper describes the present and future application of the 60-cu.-yd dragline and truck-shovel pre-stripping fleet in 1•ecovering 5- to 40-footthick coal seams in mountainous terrain. Deep blastholes, coal flow demands, spring ""run-off"", seam and inter-seam thrust faulting, limited seam outcrop data and regional faulting are a few of the problems encountered in this application. The author discusses these problems and their solutions as applied at Fording Coal Ltd."

Jan 1, 1976

By C. R. Ross

"THE ASSESSMENT of pneumoconiosis-producing dusts in mines and other industries is usually undertaken for one or more of three reasons: (1) To compare dust exposures at particular operations with standards of permissible dustiness in order that hazards may be evaluated and preventive procedures initiated where required.(2) To study particular operations with the objective of improving dust control devices or procedures by locating dust sources. (3) To obtain data which, along with the results of medical investigations, may assist in understanding the causes of dust-induced diseases or aid in the establishment of permissible standards of dustiness. Most dust measurements are made for the first of these reasons -to evaluate dust hazards so that they may be controlled. For this purpose, four quite different assessment techniques have been in widespread use for many years. One of these is based on the konimeter, an instrument familiar to most .Canadian mining men; a second on the impinger, which is also widely used in Canada, and almost exclusively so in the United States; a third on the thermal precipitator, used extensively in Britain and South Africa; and a fourth on the tyndallometer, a light-scattering instrument used in Germany."

Jan 1, 1960

By C. H. Attwood

Introduction In presenting this paper on the water-power resources of the Province of Manitoba, it was considered that a brief resume of the power resources of Canada, of the power already developed, and its utilization in the industries 9f the country, would be of particular interest in showing the rapid progress that has already been made. Amongst Canada's national assets, water power occupies a foremost place because of the facilities it provides for the development of her other great natural resources. The rapid development of the mining, pulp and paper, and general manufacturing industries, and the concomitant growth in urbanization, with its numerous demands for domestic, commercial, and municipal service power, have combined to stimulate hydraulic development to a point surpassing even the most sanguine predictions of a few years ago. With the bringing into operation during 1928 of hydraulic turbines aggregating over 550,300 h.p., and of a further 378,400 h.p. in 1929, Canada's total hydraulic development at the end of 1929 amounted to over 5,700,000 h.p., and in this year, 1930, the active construction in hydro-electric plants throughout the country totals in excess of 1,600,000 h .p.

Jan 1, 1930

By Paul Girard

"The copper property of Madeleine Mines Ltd. is in Lapotardiere and Boisbuisson townships, Gaspe North. The initial find was made in 1964, and subsequently a copper deposit of 5.3 million tons of ore was outlined. The property lies in Ordovician sedimentary and volcanic rocks near the major granite intrusive of the McGerrigle Range. The host-rock is a 300-foot-thick metamorphosed silty shale unit, close to the contact of the intrusive. The structure itself coµsists of a southerly-dipping monocline or the south limb of an anticline, on which a large dragfold has been imposed.Chalcopyrite, bornite and chalcocite are the principal sulphides present in the ore. Of particular interest is the zoning arrangement of these sulphides. The orebody is chimney-like in shape and appears to be a fracture-filling deposit that is genetically related to the granite intrusive and is confined within a highly fractured zone of very brittle rock. The deposit presents features uncommon to any of the other known copper deposits in the Gaspe Peninsula."

Jan 1, 1969

By M. B. Myers

The subject matter of this paper will be discussed under three main headings. 1.-Fire-Resistant Fluids: (a) the need for such materials, based on historical events; (b) a definition of fire -resistant fluids; (c) general description, characteristics, operational parameters, advantages and disadvantages of oil-in-water emulsions (HFB), water-polymer fluids (HFC) and anhydrous or synthetic fluids (HFD). 2.-A review of equipment associated with the use of fire-resistant hydraulic fluids; (a) performance testing of hydraulic equipment, i.e. gear pumps, vane pumps, axial and radial piston pumps, hydraulic motors, etc., pressure, speed, filtration limitations, etc., and effects on valves, elastomers, paints, etc.; (b) hydraulic system design features and selection of suitable units; (c) types of mining applications currently employing fire-resistant fluids. 3.-Test methods used to evaluate fire-resistant fluids: (a) fire testing methods, i.e. wick tests, spray ignition testing, hot manifold tests, factory mutual tests, all to establish fire-resistancy parameters and acceptance; (b) new developments in fire-resistancy evaluation; (c) the examination of other performance tests, e.g., effects of evaporation, sliding wear, life of rolling element bearings, etc.

Jan 1, 1979

By D. C. McKechnie

To the examining engineer, the ever-recurring problem involving the valuation of ore in a prospect presents at different times highly divergent aspects- some entirely physical or mathematical, others essentially personal. The majority of the problems discussed in this paper are obvious to the engineer, and need little elaboration. By the prospector and the general public, however, a number of these questions are often and completely over-looked, or else approached in such a way as to produce final results which are, to say the least, misleading and at times decidedly erroneous. While the purpose of this paper is to deal with prospects or potential mines, many of the problems considered apply equally well to mines with developed ore reserves. As the usual showings on a prospect consist chiefly of a few open-cuts and a limited amount of underground development work, an estimation of the actual ore reserves is a question of minor import, and seldom enters appreciably into an estimation of the probable value of the particular property. The physical valuation of a prospect mainly involves the consideration of such subjects as the general geological features exposed, the strength and type of mineralization, the width and persistence of any associated veins, shear zones, fractures or contact zones, together with the possible grade, size, and continuity of any ore-bodies that may there occur.

Jan 1, 1930

By G. M. Ritcey, A. W. Ashbrook

"This paper summarizes the optimum leach conditions for each Of several cobalt-containing arsenical feed materials, describes the solution treatment prior to purification of cobalt recovery, and discusses the plant operation on one feed as well as the treatment of effluents.IntroductionDuring the period 1962-1964, when the demand for uranium was low, Eldorado Mining and Refining Limited (Eldorado Nuclear Limited) made a decision to undertake a three-year diversification program. One area chosen in this program was that concerned with the processing of cobalt-nickel materials. Many such materials were evaluated over the three-year period, ranging from tailings, residues, ores, concentrates and speiss to metal scrap. Cobalt feed materials, on which much of the effort was concentrated, were those containing arsenic together with other metals such as silver, copper, nickel and iron. This paper describes the treatment of arsenic-bearing feed materials (ranging from 0.3 to 570/0 As) and the subsequent purification stages required before the separation and recovery of high-purity cobalt. Because of the current interest in treating cobalt ores, it seemed appropriate that the information on the treatment of various cobalt feeds should now be made available . Although a large amount of data were generated during the research and process development program, a complete scientific correlation and understanding could not be achieved. Nevertheless, the data may provide a guide to others involved in processing not only cobalt, but other arsenical ores."

Jan 1, 1981

By Robert Lee

"International competition is presenting the Canadian steel industry with a major challenge. While Canadian companies have invested in new technology, research and development, activity by Canadian industry, in general, lags significantly behind that of its major competitors. While OECD countries increased their research and development spending during the 1980s, Canada's R&D funding levels have changed little since the early 1970s and have actually dropped since 1986, despite greater public discussion on the issue. This fact is reflected in the relatively slower pace of innovation in the Canadian steel industry, despite the efforts of both government and industry.In addition, there are a number of factors that undermine the competitiveness of the Canadian steel industry, in particular in relation to the United States. Among these are higher interest rates, labour costs and tax rates, as well as an overvalued Canadian dollar. Canadian steel companies are thus feeling the full impact of the current economic recession. This recession, combined with recent strikes, have, for example, caused serious losses for Algoma and Stelco.In spite of these objective difficulties, the Canadian steel industry has been able to survive and continues to strive for a leadership position in the world market. Since World War II, heavy investment in new technology has allowed the industry to upgrade its facilities and increase productivity, while at the same time improving quality and reducing pollution. This last point is particularly important in view of public insistence on improvements to the quality of the environment. Over the next decade, this technological innovation must be maintained and intensified if industry is to meet the challenge of international competition and attain a leadership position."

Jan 1, 1991

"Shales play a major role in the stability of slopes, both natural and engineered. This paper attempts to provide a review of the state-of-the-art in shale slope stability. The complexities of shale terminology and classification are first reviewed followed by a brief discussion of the important physical and mechanical properties of relevance to shale slope stability. The varied mechanisms of shale slope stability are outlined and their importance highlighted by reference to international shale slope failures. Stability analysis and modelling of anisotropic rock slope masses are briefly discussed and the potential role of brittle rock fracture and damage highlighted. A short review of shale slopes in open pits is presented.INTRODUCTIONShales have been stated to form approximately 58% of sedimentary rock so it is not surprising that they are frequently encountered in both natural and engineered slopes. They represent challenging environments for slope stability due to the wide variation in their engineering properties, their changing behaviour with time due to geomorphic processes and the variation in the failure mechanisms as a function of both stratigraphy and tectonics. An extensive body of literature exists on the terminology and classification relevant to shales; it is not possible in the scope and length of the current paper to review these works in detail and the reader is referred to Farrokhrouz and Asef (2013), Bell (2000) and Goodman (1993) for detailed discussions. It is arguably the case that no universally accepted classification of shales exists today and depending on the field of application the terminology varies widely. Shales in slope stability, for the purpose of this keynote paper, are taken to include material varying in properties from weak rocks to soils and therein lies one of the most challenging aspects in shale slope characterisation for engineering purposes. They have been classified as “rock-like” or “soil-like’, (Underwood 1967) or compacted and cemented, Table 1, Yagiz (2001). Classifications have considered numerous factors including composition, cementation and a wide range of engineering properties.The propensity of shales to degrade with time due to geomorphic processes has resulted in an important aspect in their classification, that is, the attempts to incorporate slaking, durability and swelling and softening behavior through purpose developed testing methods (Gamble 1971, Morgenstern and Eigenbrod, 1974). Figures 1 and 2 show examples of terminology used to describe argillaceous materials and some proposed engineering classification schemes (Grainger 1984 and Bott 1986). Corominas (2014) provides a recent classification of argillaceous rocks and their durability relating five stages of slope deterioration to the texture of the rock on Ternary diagrams. No attempt will be made here to discuss the merits of the proposed terminology and classifications, suffice it to say, that the controversy and flux surrounding these issues is a strong indicator of the complexities in the behavior of these materials. In this paper the author will consider slope stability in the materials indicated in Table 1, Figures 1 and 2 without undue focus on terminology. At the lower strength limit of shales the engineer must design slopes using the principles of soil mechanics which may vary from the simple Mohr Coulomb plasticity constitutive criterion to modified critical state models, some even attempting to incorporate softening behaviour in the weaker clay shale materials. Given the transitional nature of shale materials several workers have treated overconsolidated clays and clay shales using concepts such as peak and residual shear strength, brittleness index and softening. Martin and Stacey (2013) provide a useful review of the importance of weak rocks in open pit mining, with mudrocks as a specific member, and note the importance of delayed failure, progressive failure and loosening in the stability of"

Jan 1, 2015

By T. Kerr, C. Mattich, J. Wilson

"In refractory gold concentrates, gold is occluded in sulphide minerals preventing efficient cyanide leaching. Hence, roasting is used to oxidize sulphur and organic carbon, the latter being necessary to minimize recovery loss through the preg-robbing effect. In 2009, Outotec commissioned the circulating fluidized bed roaster at Syama gold mine in Mali. Since 2013 Resolute and Outotec have been implementing improvements to the roaster performance with the capacity increasing from 8000 t/month in 2013 to above 13,000 t/month in 2016, while achieving a residual sulphide sulphur and organic carbon contents of below 0.1 wt.% and 0.4 wt.%, respectively. Thus a gold recovery in the CIL of above 90% is attained. In 2016, Outotec audited the Syama roaster. The analysis resulted in the Low Carbon Roaster (LCR) upgrade concept which (i) allows re-processing of calcine dust from the spray cooler and ESP after pelletization and (ii) allows the roasting of a further fine-organic carbon rich feed, i.e. de-slime circuit tailings. The LCR upgrade aims to reduce organic carbon to <0.2 wt.% and increase roaster-leaching gold recovery by >3%. Project development included extensive testwork. The LCR process is expected to become operational during FY 2019.INTRODUCTION Double refractory sulphide ores exhibit the characteristics of gold locked within pyrite grains, in the presence of preg-robbing natural (organic) carbon. Hence, to achieve high recovery during subsequent processing steps, i.e. cyanide leaching, oxidation of sulphide sulphur is required, producing a porous calcine by way of a roasting step. This allows for the gold contained within the pyrite grains to be accessible during cyanide leaching. Furthermore, it is necessary to oxidize the organic carbon. Oxidizing the organic carbon is essential as gold recovery loss occurs as a result of gold-cyanide complexes being adsorbed on organic carbon, this phenomenon is termed as preg-robbing (Miller et al., 2016). The gold absorbed on the organic carbon is lost, reporting to the tailings stream. Hence, the aforementioned oxidation of sulphide sulphur and organic carbon is the process goal. Nonetheless, the latter must occur at a controlled temperature which is concentrate/ ore specific, since the pores of the produced calcine should not sinter, as this makes the gold contained in the calcine less accessible during leaching, leading to gold recovery loss. The tight temperature control requirement is a decisive factor in the choice of a Circulating Fluidized Bed (CFB) as the roasting reactor, due to the excellent mixing characteristics of the CFB which results in temperature homogeneity of (+/-10°C). Roasting of double refractory ores, as described above, can be included in the flowsheet after comminution and grinding, a process termed as whole ore roasting, or by including a flotation circuit termed as concentrate roasting. Roasting the flotation concentrate results in less solid flow, increased sulphide sulphur grade and organic carbon content resulting in a higher heating value and higher gold content. A typical composition of the Syama ore and concentrate is given in Table 1. Ore average values presented correspond to the period 2015, while concentrate values are typical for the flotation performance throughout the period 2012–2015."

Jan 1, 2017

By G. A. Vissac

In this paper we intend to deal particularly with the economic side of coal washing as it applies to our mines. We will then discuss why the dry-cleaning process has been selected, and give a brief description of our plant, dwelling only on its specific features and referring the reader to the numerous papers published on the subject for any details on the principles and machinery used in dry cleaning. ECONOMIC DISCUSSION The washery introduces an extra cost for depreciation, operation, and loss in treatment. A certain proportion of the coal, now being sold, and which the miners have been paid for. will have to be wasted. As a whole, the total increase in cost would be approximately 60 cents per ton. On the possibility of recovering this amount depends the success of the washery. There are two advantages to be expected from the washery, the first, which occurs at the mine and which will be certain; the second, more difficult to estimate, because it depends upon convincing our customers that they should pay more for a better product.

Jan 1, 1924

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 S. Noh, T. K. Kim, B. O. Lee

Future nuclear reactor systems such as a sodium-cooled fast reactor are being designed under severe conditions in terms of operating temperature and irradiation fluence compared to current commercial reactors. For realization of such systems, it is necessary to develop an advanced structural material having both high strength and irradiation resistance at high temperatures. Oxide dispersion strengthened (ODS) steel is considered as one of the most promising structural material because of its excellent creep and irradiation resistance on the basis of uniformly distributed nano-oxide particles with a high density. Up to now, ODS steels have been intensively studied and developed to apply these materials to the in-core structural component of future nuclear systems. Several advanced ODS steels were designed and fabricated by a mechanical alloying, hot isostatic pressing and hot extrusion processes. This study focuses on the effects of heat treatment parameters during the fabrication process parameters on the microstructures of ODS steels for future nuclear system applications.

Jan 1, 2015

By X. M. Zhou, T. Wu, He X. N.

"In order to study the support effect of concrete in the surrounding rock of a metal mine, the concrete and surrounding rock were comparatively studied. Firstly, the general situation of the ultra-kilometer deep shaft in Xincheng, surrounding rock and geological conditions are introduced. Secondly, the experimental scheme of material mechanical properties of surrounding rock and shaft lining concrete based on same standard dimension and shape are examined, and the mechanical tests of rock and concrete based on different shapes and sizes are carried out. The study shows that the compressive strength value and elastic modulus of the rock cube are 1.28 times and 1.78 times that of the cylinder, and the Poisson's ratio is 0.77 times. The dimensional effect law of the concrete cube and cylinder test data is consistent with the rock law. However, the test results of the concrete are less discrete than the rock; the test also shows that the strength and elastic modulus of the concrete lining of the main shaft of the Xincheng are much smaller than the surrounding rock that is also used as the concrete aggregate, which indicates that the support of concrete lining in the surrounding rock shaft behaved weakly. Based on the development of the modern NATM rock support theory, it is suggested that the mechanical test standard of artificial support materials should be unified into the mechanics test standard of natural rock, which will help to improve the accuracy and practicality of scientific calculation of geotechnical engineering.INTRODUCTIONConcrete and rock mass are usually attributed to a class of materials called frictional materials or geotechnical materials, of these two kinds of materials, the first is man-maded and the second is natural. The attentive scholar can find that there are many differences in the test criteria for the mechanical properties of the two kinds of materials among different industries or departments, reflecting the differences in their sources, tradition, and the application thoery of material strength among them.There is a situation wordwide, that there are many testing standards of the same material mechanical parameters such as elastic modulus, compressive strength, etc. The cube with a side length of 150 mm is adopted as a common sample in the architecture department in China, while a cylinder with a diameter of 50 mm and a height of 100 mm is as a standard specimen in geotechnical department.Knowing that mechanical parameter values are strongly affected by the the size, shape of specimen and loading rate etc, that is to say the mechanical parameter values of the same material are completely different when obtained from different test with different standards. However, such a problem has been long neglected in geotechnical engineering."

Jan 1, 2019

CONSTRUCTED WETLANDS (CWs) ?Human-Constructed ?Built Specifically to Remove Contaminants ?Can Treat a Wide Variety of Wastewaters Including Stormwater(SW) ?Three Major Kinds ?Pond Wetlands ?Free Water Surface Wetlands (FWS) ?Sub-Surface Flow Wetlands (SSF) ?HSSF & VSSF

May 1, 2009

By L. J. Cunningham

Introduction The property of Rouyn Merger Gold Mines, Limited, is in Rouyn and Joannès townships, Western Quebec, seven miles east of the town of Rouyn. Traversing it is the east-west trending Cadillac-Bouzan fault. Diamond drilling in 1944 and 1945 along a shear zone south of the fault indicated an ore deposit lying at the contact between sedimentary and volcanic rocks and dipping approximately 60° to the northwest. In the summer of 1945 it was decided to sink a shaft to investigate the indicated ore zone. In the immediate vicinity of the deposit, bed-rock is overlain by clay beds, in some places as much as 70 feet thick. Consequently, possible shaft sites were limited to those locations where overburden would not be excessive. The most favourable site was about 125 feet to the south of the ore zone as projected vertically from bed-rock to the surface. Accordingly, it was decided to sink the shaft at this point, with an inclination of 60° N. W., paralleling the dip of the ore zone.

Jan 1, 1948

By P. D. R. Maltby

This paper describes the background and markets for calcium carbonate and silica sand in Canada, as well as the results of recent test work carried out at the Ontario Research Foundation. Tests on sericite, tremolite, vermiculite, barite and graphite are also mentioned.

Jan 1, 1979

By Kuwauchi. Y., M. Barati

Recycling of dust using a rotary hearth furnace (RHF) has gained considerable attention in the past two decades for the sustainable production of steel with less environmental impact. In order to further promote the recycling of electric arc furnace dust and carbonaceous wastes using the RHF process, a mathematical model was developed to predict the reaction behaviour of dust-reductant composites. The reduction kinetics of zinc and iron oxides as well as the volatilization behaviour of volatile matter in the reluctant were considered. The modeling approach and some preliminary results are presented in this article.

Jan 1, 2011

By C. H. Stockwell

THE Eastern Townships of Quebec have been the chief Canadian source of chromite. Production, however, has never been large and, except for a period of steady but small output between 1894 and 1909, mining has been active only in war time. The known deposits are too small or too low grade to compete with overseas sources in normal times. During the last war, shipping difficulties and a greatly increased demand in the United States resulted in high prices and a ready market for low-.grade material. The Quebec chromite industry flourished and played an important part in relieving the wartime shortage. Shipments in 1918 .amounted to 15,600 tons of crude ore and 6,400 tons of concentrates. At the outbreak of the present war it was natural to turn again to the Quebec field as a possible source of this strategic mineral. Some of the old properties have since been opened by private and government money and some new deposits have been found. Total mill capacity is 750 tons per day, as compared with 200 to 300 tons in 1918. During 1940, 1941, and 1942, about 85 chromite deposits were examined by the Geological Survey in a belt 100 miles long and up to 7 miles wide. A part of this belt, about 35 miles long, in which the geological features ?were not well known, was mapped on a scale of 1/2; mile to an inch.? Small ..areas around some of the deposits were mapped in detail, on scales of 20 to 200 feet to an inch. Some geophysical work was done but did not result in the discovery of ore. Prospecting by stripping and trenching was then undertaken and chromite ore was uncovered at several localities. The above work was done by the writer and by J. W. Ambrose, who has kindly contributed his results for incorporation in this paper. Y. O. Fortier actd as assistant in the geological work and, in 1942, was in charge of a sub-party engaged in geological mapping. The author is indebted to H. C. Cooke and J. W. Ambrose for reading the original manuscript and for offering many helpful suggestions for its improvement.

Jan 1, 1944