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By V. N. Mackiw, H. Veltman

"A process is described which permits the separate recovery of lead and zinc from complex low-grade sulphide concentrates such as are produced from the New Brunswick type of disseminated pyrite ores. This process calls for the preparation of a lead-zinc bulk concentrate from the original ore by flotation. The bulk concentrate is then oxidized under pressure in autoclaves in aqueous sulphuric acid solution, such as return electrolyte from zinc electrolysis. This yields a zinc sulphate solution and a residue containing lead sulphate, unaltered pyrite and elemental sulphur generated during the oxidation. After the oxidation, the leach slurry is briefly heated to above the melting point of elemental sulphur and then cooled. Thus, pellets containing pyrite and elemental sulphur are formed, and they are separated from the lead sulphate by screening and/or flotation. Laboratory tests have shown that about 95 per cent of the zinc and lead can be separately recovered from complex bulk concentrates. Process possibilities are discussed."

Jan 1, 1967

By H. C. Gunning

In spite of the fact that mining has been more or less active in the northern part of Vancouver island since the late 'nineties', there seems to be a remarkable lack of information regarding the nature and development of the region. Recently the operations at the Old Sport mine of the Coast Copper Company, Limited, and spectacular copper discoveries in the vicinity of Nimpkish lake, have directed the attention of the mining fraternity to the district. The writer spent the summer of 1929 making a reconnaissance examination of the general geology and mining properties of the area between Quatsino sound and Nimpkish lake, and he feels that a short paper describing the nature and mining possibilities of the region should be of interest at this time. A more detailed account of the ?geology and of the mining properties will be published in the forth- coming Summary Report of the Geological Survey. A short paper dealing with the Nimpkish Lake district was presented at the Annual Meeting of the British Columbia Division, held recently in Vancouver.

Jan 1, 1930

An Atomic Force Microscope (AFM) was used to measure the surface forces between glass sphere and silica plate in CnTAC1 (n=12, 14, 16, 18) solutions. The results showed the presence of long-range attractive forces that can be fitted to single exponential functions. With a given surfactant, the attractive force increased with increasing concentration, and reached a maximum at the point of charge neutralization (p.c.n.). The decrease in the attractive force above the p.c.n. is probably due to the inverse orientation of the surfactant molecules. A plot of the log (p.c.n.) vs. the number of carbons in the hydrocarbon chains of the Cn TACI homologues showed a linear relationship with a slope of -0.37, indicating that the surfactant adsorption entails a decrease in free energy by -0.85 kT per mole of CH2 (or CH3) group. These results suggest that the adsorption of long-chain surfactants is controlled by hydrocarbon chain association during the process of forming surface hemi-micelles (or domains). Possible origins of the long-range attractions are discussed on the basis of the results presented in this communication.

Jan 1, 2006

By S. R. Noble, F. R. Harris, E. T. C. Spooner

"The Logtung deposit discovered in 1976, is an example of large tonnage (162 million tonnes), low grade (0.13% WO3 and 0.052% MoS;) W(scheelite)-Mo mineralization related to multiple felsic intrusions. Because mineralization is predominantly fracture-controlled (> 95 %) rather than disseminated, Log tung is not a skarn deposit. Metamorphism of the Logtung country rocks (interbedded calcareous shale and graphitic quartizite) to a series of competent reaction skarns (quartz-diopside-garnet calc-silicate, biotite quartzite and wollastonite-vesuvianite calc-silicate) clearly precedes W-Mo mineralization. Hence mineralization was related to permeability created by hydraulic fracturing and not replacement processes.Logtung shows a theme of several phases of mineralization (4) related to multiple intrusions (>2) which is similar to that of the Climax and Urad-Henderson Mo systems. The earliest quartzmolybdoscheelite vein system, which consists of a typical ""porphyrystyle"" crackle-breccia of thin (0.5 mm to 4 mm) quartz-garnetdiopside- molybdoscheelite veins, is related to a high Si02 (approx. 76%), seriate-porphyritic monzogranite stock (approx. 2 km by 0.5 to 1 km) of Cretaceous age (118 ±2 Ma [2u]; Stewart, 1983). Later quartz-pyrite scheelite (fluorite-KINa-feldspars-molybdenite) veins, with prominent green, hornblende-bearing alteration selvages, and quartz-molybdenite (-pyrite-jluorite-scheelite) veins are related to a quartz-feldspar-spessartine-rich garnet porphyritic felsic dike complex approximately 500 m across. Both intrusive phases have anomalously high Wand Mo concentrations of about 100 ppm and 50 ppm respectively, which Stewart (1983) attributes to a primary enrichment. The final stage of mineralization consists of a prominent 4.5 km by 1 km zone of 1 em to 1 m wide polymetallic sheeted veins centred on the felsic dike complex. The system is zoned from quartz scheelite-molybdenite-pyrite-blue-green beryl-jluoritebismuthinite veins in the core to Pb-Zn-Ag veins with abundant arsenopyrite and minor Sn (approx. 0.1%) in the northeast. The focus of recurrent intrusive and hydrothermal activity was located above a flank or nose of the monzogranite stock.The distribution of WO3 and MoS2 grades within the approximately 750 m (across) by 300m (evaluation depth) mineralized zone is a result of the variable superimposition of the four separate vein systems each with different W:Mo ratios. Well-defined Wand Mo ore, shells such as those at Climax, Henderson and Mt. Emmons did not develop at Logtung. The upper surface of the mineralized zone, as shown by the 0.03% MoS2 contour defines an elongate dome with an apical region approximately coincident with the felsic dike complex. Hydrothermal alteration occurs as well-defined vein selvages, and not as pervasive zones.The Logtung deposit shows many similarities to porphyry Mo deposits in the western Cordillera and may be identified as a porphyry W(scheelite)-Mo deposit, with a W:·Mo ratio of 3.3:1. The principal reasons are: (1) mineralization is spatially associated with porphyritic granitic intrusions and (2) much of the scheelite and molybdenite occurs in typical ""porphyry-style"" vein stockworks"

Jan 1, 1995

By A. Kapoor, L. Morin, S. Mortazavi, P. Béedard, Gould. W. D., A. Kuiper

The degradation of thiocyanate in a simulated gold mill effluent was studied using a laboratory scale rotating biological contactor (RBC). Complete SCN- removal was obtained at temperatures of 8 and 12°C, and a hydraulic retention time of approximately 3.3 h. The NH4+ produced by thiocyanate hydrolysis was oxidized by nitrifying bacteria to NO2 and NO3-. The HS- produced by thiocyanate hydrolysis was chemically and biologically oxidized to elemental S, which was subsequently biologically oxidized to sulfate. Incomplete sulfur oxidation occurred in the RBC, particularly at 8°C and elemental sulfur deposition was observed on the RBC disks. The RBC feed exhibited toxicity to rainbow trout but the RBC was effective in removing the acute toxicity of thiocyanate.

Jan 1, 2005

By M. H. Leite, R. Corthésy, D. E. Gill

"La connaissance des contraintes naturelles qui prévalent dans les massifs rocheux est un prérequis indispensable pour la conception sécuritaire et économique des excavations comme on en retrouve dans les exploitations minières souterraines. Certains chercheurs se sont attardés à colliger les résultats de mesures de ces contraintes et les ont utilisés pour produire des modèles de prédiction basés sur leur traitement statistique. Ces modèles de prédiction sont très populaires auprès des exploitants miniers puisqu’ils permettent, du moins dans les étapes préliminaires de design, d’obtenir de façon s’apéconomique mais approximative, une partie des paramètres dont ils ont besoin. Dans le cadre d’un projet initié en 1994 avec la collaboration de l’IRSST, il a été décidé de produire un modèle de prédiction englobant une partie de la zone périphérique de la faille de Cadillac, soit une zone plus restreinte que le Bouclier Canadien utilisé jusqu’ici comme région pour l’élaboration de tels modèles. Pour produire ce modèle de nouvelles données obtenues avec une technique permettant d’exercer un excellent contrôle de qualité ont été ajoutées à celles déjà disponibles. Une telle régionalisation des données de base permet d’obtenir un modèle où les intensités et les orientations des contraintes principales sont beaucoup moins dispersées que ce que rapportent les modèles publiés jusqu’à ce jour. Enfin, il est démontré que le modèle proposé pour la région étudiée est en toute probabilité plus sécuritaire que les modèles plus généraux publiés à ce jour. Knowledge of the in situ state of stress existing in a rock mass is essential to the safe and economical design of underground mining excavations. Prediction models have been published, based on the statistical treatment of stress measurement results. Such prediction models are very popular among mine operators because they allow them, at least at a preliminary design stage, to economically obtain part of the information needed, even if this information is approximative. In 1994, a research project financed by IRSST was initiated aiming to produce a prediction model that would comprise a peripheral zone around the Cadillac fault. This region is more confined than the Canadian Shield on which the existing prediction models have been based up to now. In order to produce such a model, existing stress measurement results have been used in conjunction with new stress measurements that have been performed based on a technique which allows full control of the quality of the measurements. Restricting the data upon which the model is based to a more specific region gives a model in which the intensities and the orientations of principal stresses are far less scattered than the results published to date. Finally, it is shown that the proposed model is probably safer for the studied region than the models previously published."

Jan 1, 1998

By R. S. Bigelow

Part 1.- Metal Mines Early experiments with mechanical loaders in metal mines were confined largely to machines of the shovelling type and generally air-operated. Although the first application of the scraper to metal mines dates back to 1910, it was not until about twelve years ago that it came to be used extensively. Generally, the scraper gives better results in metal mines than in coal mines, as degradation due to soft bottom and breakage are not factors, but it has a wide range of application and is successfully used in the mining of salt, potash, gypsum, zinc, copper, and a variety of ores, from soft material to hard chunky ore which settles compactly. Today, the scraper has replaced to a large extent the shovelling type of machine in metal mines. Scrapers have offered an inexpensive solution for the mucking problem and are now employed in most mining districts throughout the world. They are operated by labourers of all colours and degrees of skill. Each installation, however, requires individual study on the part of the mine mechanical department to determine the type of scraper, horsepower of hoist, and most economical speed of rope, as well as method of rope rigging. Unfortunately, the scraper has no power to select pay ore from waste and its suitability for use under circumstances which might require sorting of the ore can only be decided by a weighing of the economic factors involved

Jan 1, 1931

By Dave Shook

A Mineral Processing facility in Montreal has recently implemented a leading-edge intranet solution for monitoring the performance of plant operations, and providing condition-based maintenance. This innovative multi-faceted software implementation incorporates: web-delivered plant information systems; area-wide control loop performance assessment (using sophisticated algorithms to evaluate poorly performing controllers); and integrated alarm management functions. The system has enabled a project to improve plant operations through better process control. Maintenance technicians, engineers, supervisors and managers all can see the performance of the controllers, and the performance of the plant itself, through webdelivered graphics and reports. Information is combined from many sources, real-time, historical, relational and analytical, to provide a complete picture of plant operation. The web-based solution centralizes the administration of user access, and simplifies the deployment of several different kinds of information to many desktops. It is an extensible system that allows users to create and share their own web pages and data views. The paper will discuss the solution architecture and the improvements the I.T., operations, maintenance, and engineering groups have experienced, and overall benefits to the facility.

May 1, 2002

By P. G. Lazenby

This paper describes the latest instrumentation improvements in the INPUT Airborne E.M. System, particularly the new electronic signal-processing techniques. Several anomaly examples illustrating these techniques are shown.

Jan 1, 1973

By A. P. Schissler

Mining has several characteristics, uncommon in other business sectors, which pose additional challenges to the implementation or design of IT and management systems that use the information. Understanding these characteristics would improve the chances of successfully importing new information technology and management techniques to mineral producers. The most important characteristics that should be understood are workplace issues, the industry’s dual nature of being a continuous construction project using cyclical factory processes, labour challenges, workplace culture, information availability, integrative data elements, and the current technical education of mining engineers. These characteristics were taken into account in two applications of information technology and systems design at operating companies. The research and consulting projects focused on the development of an IT-enabled performance management system at several underground metal mines in Canada and an integrated data warehouse for surface mines spread throughout the United States and Latin America.

Jan 1, 2006

By N. T. Oo, L. D. Hutton

"The Banora Point Upgrade Project is a 2.5km long six-lane divided freeway in northern New South Wales, Australia. The geology at the project area comprises a volcanic succession of variably weathered basalt flows and agglomerate deposits that reach 48m in thickness and overlie Mesozoic sedimentary rocks. A site specific rock classification system was developed that characterised all the rock units based on the engineering properties governing the rock mass behaviour i.e. intact rock strength and defect characteristics (spacing, aperture, infilling, wall roughness and weathering) irrespective of the geological origin. This approach simplified the design and the on-site verification processes. Based on this classification system, rigorous quantitative statistical assessments of the available geological information including various laboratory and field testing were performed to derive the geotechnical design parameters for various rock classes. These parameters were used to complete geotechnical designs of retaining wall systems. INTRODUCTIONThe Banora Point Upgrade Project is a 2.5km long six-lane divided freeway in northern New South Wales, Australia. The key features include two interchanges, a 300m long viaduct, a large cutting through Sexton Hill with an associated 100m wide Land Bridge and retaining walls reaching 490m long and up to 22m high. This paper focuses on the derivation of representative geotechnical parameters for geotechnical design of the retaining structures supporting Sexton Hill Cutting including bored pile retaining walls and soil nail walls. The geology at the project area comprises a volcanic succession of variably weathered basalt flows and agglomerate deposits that reach 48m in thickness and overlie Mesozoic sedimentary rocks. Due to the complex geological nature of the site, an understanding of the regional and local geology, the typical behaviour of individual geological units and the implication of onsite variations from design intention are the ultimate challenges to the geotechnical engineer in order to select representative geotechnical parameters for design."

Jan 1, 2015

By S. P. Chong, N. C. Shih, G. A. Turner

Fine powders, with the bulk of the particle diameters Jess than 10 microns, were aerated so that each particle was, on the average, separated from its neighbours by 1.3 to 2 mean diameters. In this state, measurements were made of the viscosity and settling rate of the powder, and the interfacial tension between it and a moist pellet. From the viscosity measurements, qualitative analogies are drawn between the behaviour of the aerated powder and that of a dense gas near its critical point.

Jan 1, 1970

The primary steel industry of the Prairie Provinces consists essentially of three companies whose total annual melting capacity, as of January 1, 1963, was 333,000 net tons. These companies have steel rolling facilities. In addition, there are five other companies producing steel castings by melting scrap in electric furnaces which, with the plants having rolling facilities, gives a total annual furnace melting capacity of 380,000 tons. Since 1954, the annual production of steel ingots and castings has ranged from a low of 66,588 tons, in 1954, to a high of 211,138 tons in 1961. The present facilities on the Prairies for making steel ingots from scrap, and rolling them to produce light merchant mill products, appear to be sufficient for many years ahead. Steel scrap, as electric furnace feed to make steel ingots for the present line of products, will probably continue to be available at reasonable prices either on the Prairies or from the north-central United States. It is recognized, however, that residual elements in scrap may be-come of greater significance and necessitate more rigid control of scrap quality.

Jan 1, 1963

By T E. Tibbetts

This paper deals with coal sampling in general and with mechanical coal sampling in particular. The necessity of obtaining representative samples is emphasized. Other sections of the paper are devoted to the design and selection of automatic samplers, with a consideration of the three main types, and the testing, operation and maintenance of these samplers. The cost of the installation of an automated sampling system must be related to the value of the material to be sampled, to the volume of coal involved, and to the savings in labour and economy which can be achieved. Introduction T HE Committee?:; on Coal Sampling of the Coal Study Subsection, Thermal Power Section (Eastern Zone), Canadian Electrical Association, was established in November, 1963, to "study the various problem areas of coal sampling." The first undertaking of the Committee was to at-tempt to survey the problem areas of coal sampling through an evaluation of coal sampling difficulties as experienced at both the plant design and operational levels within the electric utilities represented on the Committee. The results of this enquiry indicated that satisfactory answers to almost any conceivable

Jan 1, 1965

By G. M. Ritcey

The recovery of copper from low-grade solutions res ulting from dump leaching is well known, whereas the recovery from highly concentrated copper solutions has not been practiced. This paper discusses the use of Ashland Chemical's Kelex 100, a substituted quinoline, for the recovery of copper from solutions resulting from leaching copper-nickel concentrates. A flow sheet is described, and an economic comparison shows Kelex 100 to be superior to either the LIX 64N or LIX 70 reagents of General Mills for the recovery of copper.

Jan 1, 1973

By R. K. Collings

The annual production of mineral and mineral-based wastes in Canada is conservatively estimated to be 400 million tons. Over 90 per cent of this amount is waste rock or mill tailings from the mining and mineral processing industry. The remainder are slags and ashes from the metallurgical industry, and sludges from the chemical industry. Because of impurity content, remote location, or both, most wastes have limited usefulness and, indeed, are a liability in that they must be transported to waste disposal sites and contained therein. Certain mineral wastes do, however, have potential value. Some contain small percentages of metals that may be economically recoverable with price increases; others consist of mineral material that may be used for such purposes as road base, construction aggregate, railroad ballast, and in the manufacture of bricks or blocks. Increased interest has been shown in mineral wastes in recent years. This paper reviews the types of mineral wastes available in Canada, briefly describes a number that have potential value, and notes possible uses and related research by CANMET and other organizations.

Jan 1, 1978

"THE Canadian Advisory Committee on Coal Research, which is commonly known as CACCR, has been in existence for the past five years and has held annual meetings during that period. This Committee is comprised of representatives from: the Mines Branch, Fuels and Mining Practice Division, Ottawa; the Geological Survey of Canada; the Dominion Coal Board; and the Provincial Research Councils and Foundations. It embraces all coal research in Canada that is sponsored, for the most part, by Government funds.To bring the country's coal research activities to the notice of the Canadian coal industry, the Coal Research Committee of the Coal Division, C.I.M., passed a resolution at the 1964 business meeting in favour of recommending the publication of an annual research report prepared by the CACCR. The first such report was published in the September, 1964, issue of the C.I.M. Bulletin; the second appeared in the November, 1965, issue of the same publication."

Jan 1, 1966

By R. C. A. Thurston

INTRODUCTION THE deleterious effect of stress raisers or notches on the resistance to fatigue of machine components, and other parts subjected to repeated dynamic loading, has been well known for many years. Most engineers in the mechanical field have, at one time or another, encountered a shaft which fractured due to a poor transition fillet, a holding-down bolt which failed due to insufficient tightening or inferior thread form, or a fitted member which broke through a combination of fretting corrosion and clamping stresses. All of these are examples of the damaging influence exerted by stress raisers in fatigue. Other common forms of stress raiser which have taken their toll of dynamic components are: keyways, oil holes, splines, quenching oil grinding cracks, tool marks, and sharp changes in section; some are the result of the design, others of poor execution of the design. It is our experience in the Mines Branch1 and I feel sure this will be corroborated by other fatigue investigators, that the majority of failures are due to incorrect design or faulty preparation of the part concerned, rather than to the use of inferior material. Quite frequently, it is true that the operating conditions necessitate the presence of a 'notch', but even in such cases methods are generally available by which its adverse effect on the life of the component can be reduced or annulled. The purpose of this paper is to discuss a few typical stress raisers, and to provide information on various processes for mitigating their effects in fatigue.

Jan 1, 1951

By M. A. Creaney

"The Construction Group is responsible for the construction of all of Placer Dome’s major projects and contributes to the development of most major feasibility studies. This group includes an international collection of Placer Dome people who have built mines in Papua New Guinea, Australia, Chile, the United States and Canada. This paper outlines the changing role of the Construction Group from the early days of single projects to today, when several projects are in various phases from feasibility to construction. The projects’ total annual budgets have from time to time exceeded one billion dollars. IntroductionAs the competition increases globally between the major gold mining companies, the impetus continues to build mines at the lowest cost with the shortest construction schedule. Placer Dome has more than met that challenge by building mines around the world at a pace that was not contemplated 15 or 20 years ago. Since 1960, Placer Dome has built 30 mines and expansions at a cost of nearly 4.5 billion dollars.In the last six years alone, Placer Dome has built 14 mines and expansions, worth 2.6 billion dollars. The company’s success is due primarily to Experience, Innovation, People and Standards.The diversity between projects, let alone the pace, has been a challenge. Placer Dome has built mines around the world in a variety of extreme climates and distinctive cultures. The construction experience gained from these projects has allowed Placer Dome to develop an extensive knowledge and data base making it easier to “fast track” projects.Through the years Placer Dome has developed a human resource base. It now has an experienced and adaptable core team of people able to set up construction projects and build mines anywhere in the world. By developing standards and systems to support the projects they can act as soon as a new project is approved, and complete the projects quickly and effectively. The result is that Placer Dome now has the construction expertise to build its own mines, giving them the competitive advantage that allows them to design and construct a mine in the least time at the lowest capital cost. This was demonstrated in March 1997 with the completion of the construction of two new mines in 12 months."

Jan 1, 1998

By G. A. Gross

"The Soviet Union has enormous reserves of iron ore in many different kinds of deposits that are widely distributed in this vast land area. The present iron ore industry is based mainly on deposits in Precambrian cherty iron-formation at Krivoy Rog, Kursk and Murmansk. Extensive reserves of both naturally enriched hematite ore and magnetite iron-formation in these areas alone could sup-ply all the domestic ore required for several hundred years.Many contact metasomatic magnetite deposits discovery in recent years in the eastern Ural Mountain belt and east of the Kusnetsov basin in Siberia are being developed, with ore reserves measured in billions of tons. Oolitic limonite-chamosite-siderite ores of Cretaceous and younger age at Kerch on the Black Sea and around the east and southern perimeter of the West Siberian basin constitute some of the largest concentrations of iron in the world. These sedimentary ores are low grade, of poor quality and difficult to beneficiate. Banded jasper magnetite and hematite iron-formation in volcanic rocks of Devonian age in Kazakhstan and along the Mongolian border are of special geoloica1 significance.Iron deposits in the Krivoy Rog and Kursk areas were examined and a large number of geologists discussed their work on deposits in many other parts of the Soviet Union during the writer's seven-week study tour of mines and research institutes in Moscow, Leningrad, Novosibirsk in Siberia and Kiev in the Ukraine. The descriptive geology of iron deposits of useable ore and of marginal material has been well documented in the course of systematic work and a large number of scientists are studying fundamental problems on the origin and treatment of iron ore."

Jan 1, 1967