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By J. A. Brothers, M. R. Foran

"AbstractThis paper reviews the progress made in the manufacture of hydraulic cement from iron blast-furnace slag by simply grinding the granulated material with other constituents. The influence of the chemical and mineralogical composition of the slag, the conditions of granulation, the manner of drying, and the fineness of grinding, on the hydraulic properties of the cement, is discussed. The effect of additions of lime, portland cement, and anhydrite, alone and in combination, on the physical and cementing qualities of the mortar and concrete made from Sydney blast furnace slag, is shown in tables of data and is reviewed in some de- tail. The work at the Nova Scotia Technical College has shown that a cement equivalent in every respect to portland cement can be made from basic blast furnace slag- by the us2 of certain quantities of portland cement as an activator.IntroductionBlast furnace slag is a potentially valuable material for the manufacture of hydraulic cement. It is a by-product of the manufacture of iron in the blast furnace, and is formed by the combination of the silica and alumina .of the iron ore with the limestone flux. The metallurgist terms a slag .acid or •basic according as the percentage of lime is less or greater than the percentage of silica plus alumina. The basic slags have the •more pronounced hydraulic properties."

Jan 1, 1950

By Tim Watson

Andacollo Hypogene Project ?Overview Project description: Sulphide copper concentrator Throughput:55,000 tpd Location: Approximately 50 km from La Serena Elevation: Approximately 1,000 m ASL Start feasibility study: July 2005 Start of construction: May 2007 Construction completion: December 2009 Final cost(1,2,3):435 Million US $ (1) Excludes third party costs, 220 kV power line (2) Cost is based on a Chilean Peso to US Dollar foreign exchange rate of 535 to 1 (3) Does not include US$40.3 million for the Elqui River Pipeline Project or US$8.0 million for the stock pile cover

May 1, 2010

By R. A. Nemchek

ABSTRACT Concentrator plant design has evolved from large numbers of small grinding mills to small numbers of large mills. Consequently, plant performance often hinges on the productivity of a single large semi-autogenous grinding mill. Industry attempts to address the grinding mills’ critical nature frequently result in specifications that can be made simpler, more economical, and better focused on the project’s goals. This paper surveys current specification writing practices and proposes an improved approach recognizing that product design, procurement, manufacturing, and quality are interrelated in a successful project. The lessons learned here can apply to all types of machinery specifications.

Jan 1, 2014

By L. D. Smith

Net Present Value Impact of Discount Rate The Discounted Cash Flow (DCF) method of valuations is universally used and accepted. The main criticism of the method is that it does not recognize the value of projects long life projects. This can be seen in the preceding graph where the present value of cash flows in later years are small for discount rates over about 10%. This graph covers a project that has a 25 year operating life. It is clear from the low height of the NPV bars at 10% and 15% in the last years of the project that an additional 25 years would add almost no value to total project NPV. As an example of this effect, an colleague undertook the evaluation of a pulp and paper project. The plant could be justified, but it was not possible to justify planting the trees as they took too long to grow and so had not appreciable NPV. The plant had to purchase wood to feed the plant.

May 1, 2013

By C. E. Baltzer

This paper highlights the position of coal supply in regard to the requirements for electric-utility operations. The text and the appended tables outline the trend of thermal power development and fuel use in the electric-utility industry. Mention is made of several argumentative factors influencing the use of coal in relation to competitive oil and gas, and of the importance attached to developing a realistic understanding of the respective problems faced by the supplier and consumer of coal. * * * TREND OF" THERMAL POWER DEVELOPMENT T HE RATE OF ADVANCE in thermal power has been significant during recent years, particularly in the Atlantic Provinces, the Prairie Provinces, Ontario, and British Columbia. While dependence on thermal power in Quebec and the Northern Territories is less than in the remainder of Canada, these regions also eventually will have need for increased amounts of such power.

Jan 1, 1961

By K. J. R. Ford, Botz. M. M.

Porphyry copper ores are frequently a source of low-grade gold ore, but gold in these ores is often associated with significant levels of cyanide-soluble copper. Cyanide leaching of such ores increases flowsheet complexity and operating costs, and requires thorough planning to satisfy environmental requirements for tailings disposal and mine closure. This paper presents a review of the chemistry of cyanide leaching of gold-copper porphyry ores, carbon adsorption phenomena and means of removing base metals from leach solution. The primary economic drivers behind the processing of such complex ores are also analyzed.

Jan 1, 2011

By R. D. Brown

In his March 31, 1977 budget, Finance Minister Macdonald has attempted the delicate balancing act of stimulating the economy without reinforcing the inflationary pressures which Canada is continuing to experience. Several tax changes of benefit to the mining industry, as well as measures designed to encourage oil exploration in frontier areas, are among the budget proposals. Additional earned depletion of 66- 2 /3 %, which may be offset against income from any source, will be available on drilling costs in excess of $5 million incurred between March 31, 1977 and April 1, 1980 in connection with an exploratory well in Canada, including the continental shelf . Other changes include more favourable treatment of resource property dispositions, less restrictive rules r elating to "successor corporations" , increased capital-cost allowance on railway spur lines, the inclusion of certain production royalties in Canadian development expenses and the application of the lower "manufacturing and processing" tax rate to sulphur production. To encourage business capital spending, the 5% federal investment tax credit it to be extended an additional three years to mid 1980 and broadened to include spending on scientific research and development. The rate of credit will also be selectively increased on a regional basis, to 7.5 % in certain designated areas in Saskatchewan, Manitoba. Northern. Ontario and Quebec, and to 10% in the Atlantic provinces and the Gaspe.

Jan 1, 1977

By L. Heber Cole

Introductory During the past few years, salt (sodium chloride) strata have been encountered in western Canada in a number of wells, while prospecting for oil and gas. The ever increasing number of such wells points to the presence of a vast salt basin, the boundaries of which are at present unknown. This basin extends in a northwesterly direction from a point near the United States boundary south of Regina, crosses the Saskatchewan- Alberta boundary northwest of Unity, Sask., and continues with more northerly trend to Waterways and beyond. The beds, as encountered, appear to have a general dip to the southwest of between 10 to 20 feet to the mile and a pitch along the strike to the southeast. Thus one finds the salt strata at Waterways, Alta., at 600 feet below the surface (121 feet above sea level) whereas at Radville, Sask. south of Regina, the top of the salt is at a depth of 6,643 feet below the surface (4,430 feet below sea level). Whether this is a continuous salt basin or a series of separate basins is not yet known. We do know however, that in some of the well~ more than one salt horizon occurs while in others which normally should have encountered corresponding beds, the salt strata are absent. This latter condition, however, may occur only in the southern part of Saskatchewan, where a barren area seems to come in from the southwest. In the northwestern part of the basin, on the other hand, the occurrence of the salt strata seems to be more regular and continuous, and depths at which salt should be encountered in a drill hole in this part of the basin may be predicted with a fair degree of accuracy.

Jan 1, 1948

By R. L. Stanton

"The present contribution examines, in some detail, what appear to be the three outstanding features of the field occurrence of the conformable ""pyritic"" deposits. These are their association with fragmental volcanic rocks (and derivatives), their occurrence in sediments of near-shore formation, and their highly variable structural associations.In a recent paper it has been suggested that two such ""pyritic"" de-posits in New Brunswick may have originated as marine concentrations of volcanic base metal and sulphur compounds, and that many of their present features are the result of diagenesis, folding, and regional metamorphism. This is now put for-ward as a general explanation for the particular class of deposit considered.Such deposits should, on this hypo-thesis, be regarded quite simply as an integral part of the particular geological environment in which they occur -as a normal, though minor, sedimentarry type developed, char-acteristically, in near-shore and shelf facies of intravolcanic units formed along the margins of eugeosynclines. They should not be considered -as, for example, is required by the re-placement theory -as later features simply superimposed on a geological situation to which they are genetically unrelated. Where they are associated with folds and other structures, this may be attributed, from one in-stance to another, to mechanical migration during folding, weaknesses induced by pre-existing sulphides, and, occasionally, to fortuitousness.In the light of this postulated origin, it is suggested that the first stages in regional prospecting for deposits of this particular class should be broadly palaeogeographical. Later phases of the search should then be directed to the delineation of sedimentary facies and, finally, to the investigation of geological structure."

Jan 1, 1960

By C. Hudson, D. Tremblay, A. Frey

"A discussion of the design, challenges and successes associated with the commissioning of the gravity recovery circuit at Canada’s newest open pit gold mine - Atlantic Gold’s Moose River Consolidated Project in Nova Scotia, Canada is presented. An overview of the project, its historical significance and overall flowsheet is provided with special focus given to the design and selection of the gravity circuit equipment including the scalping screen, gravity concentrators and the novel intensive leaching technology selected for the project. The performance of the gravity circuit is benchmarked against the feasibility study process design specifications and the outcomes are discussed. Challenges encountered during commissioning are also presented, including the use of third-party automation and the effects of screen sizing on overall gravity circuit performance. Mechanical modifications made to the Sepro Leach Reactor for the Moose River project are also discussed. A detailed technical review of the mechanical and operational aspects of the Sepro Leach Reactor is provided with key operational data on leach times, recoveries, reagent usage, solid-liquid separation, pregnant solution quality and its influence on bullion purity.INTRODUCTION Atlantic Gold Corporation’s Moose River Touquoy Mill in Nova Scotia, Canada was commissioned in the fourth quarter of 2017 with commercial production declared in March of 2018. The 2 Mtpa process plant uses a conventional, gravity-CIL process. This site was previously mined in the 1870s. Interest waned in the early 1900s but resumed in the 1930s and the mine was brought back into production in 1935 until an underground mine collapse in 1936. This mining district became famous after CRBC radio commenced a ground breaking, around the clock, broadcast of the rescue operations. Over 100 million people listened to the broadcast from Canada, the United States and the United Kingdom. These broadcasts changed radio, transforming it from a medium for music to on the spot, breaking news reporting. The mill was constructed by Ausenco on a fixed price EPC contract in the historic Moose River gold mining district, 95 km north-east of Halifax by road. The mill will process ore from the adjacent Touquoy pit for the first 5+ years of operation; after the Touquoy reserves are exhausted, the mill will process ore trucked 37 km from the Beaver Dam deposit for an additional 5 years."

Jan 1, 2019

By H. H. Fairfield

THE production and inspection of the materials of war involves thousands of observations. Logical action is generally based on the interpretation of many observations. The success of such action depends upon the accuracy of the observations and the soundness of the interpretation placed upon them. There are countless instances where the observer 'sees but perceives not'; that is, the significance of a group of observations is lost, due either to faulty interpretation or to no interpretation at all being placed on the results. This condition is being partly corrected in the United Kingdom and the United States (1) by the promotion of certain principles by Ordnance officials. The term Quality Control has been adopted to describe a system of studying and controlling industrial products by methods of handling observations. In these pages an attempt is made to outline in a non-technical manner some of the ideas used in the handling of observations. Of course the authenticity of the observations determines the worth of any decisions based on them. No matter how brilliant is the theory built on unreliable sampling, it is usually of little practical value. n some fields it is almost impossible to obtain observations free from bias. Let us suppose that observers of speed in miles per hour were available for judgment: (a) a bystander, (b) a motorcycle policeman, and (c) a motorist accused of speeding. The bystander might be unbiased but probably would be very inaccurate. The motorist is usually biased on the low side. The policeman is the only qualified observer and, if over-zealous, he might be biased on the high side. Conclusions drawn from large numbers of biased observations naturally would be of little value.

Jan 1, 1943

By J. Tuzo Wilson

Abstract A division of part of the Canadian Shield into provinces believed to represent former mountain belts is attempted, special emphasis- being laid upon radioactive age determinations, the relation of Archaean to Proterozoic rocks, and the structure of the Grenville province. Original data on the distribution of radioactivity within several batholiths and their connection with ore deposits are' presented. The possible growth of continents and a theory which explains the shape and distribution of the world's younger mountain and island areas are discussed and applied to the Canadian Shield in an attempt to explain how the growth and present structure came about. The relation of the major mining camps of northeastern Ontario to fault zones is discussed in the light of this theory. Introduction The valuable symposium issued by this Institute to celebrate its jubilees emphasizes the important role of major faults in determining the location of many ore deposits in the Canadian Shield. Many of these faults are known to extend for long distances. It is therefore widely appreciated that it would be of great value if the pattern, ages, and causes of these faults were better understood. This would be particularly useful if the relations of the major fault systems to petrological and metallogenic provinces and to former mountain belts could be established. Each year the volume of available data, and hence the chance of reaching a fuller solution of this problem, increases. This article is a review of the present situation. It is accordingly based almost wholly upon the work and ideas of others, which are gratefully acknowledged. Naturally, responsibility for the selection and marshalling of the data is the writer's.

Jan 1, 1949

By J. C. Underwood

"The wear performance of grinding balls under conditions of impact and abrasion is affected by their chemical composition and structure. The selection of appropriate analyses and heat treatments that will provide both abrasion and impact resistance takes into account the effects of certain elements on structure and harden-ability, as well as the over-all effect of composition and hardness penetration on the residual stress pattern developed through heat treatment. Direct quenching from forging temperatures substantially increases hardenability over that obtained in reheat-quench practices, and can be done without undue risk of damage to the ball provided that the harden-ability bears the correct relationship to ball diameter.Average volumetric hardness and percent hardened volume are convenient parameters for quantitatively expressing the response to heat treatment and indicating anticipated wear properties. A number of factors which can lead to reduced wear life as a result of material or processing problems are reviewed and illustrated."

Jan 1, 1959

By G. M. Furnival

A PROGRAMME of structure drilling was commenced in the Southern Alberta Plains in June, 1943, for the purpose of determining the geological structure of the underlying sediments. More than 270 holes have been drilled throughout an area of some 1,800 square miles or 1,000,000 acres (see Figure 1). The Southern Plains of Alberta are covered by a mantle of glacial drift,' at places exceeding 200 feet in thickness. Only where this mantle has been dissected by deep drainage channels is bed-rock exposed to any great extent. Along such channels, surface geological mapping can be conducted to ad- vantage. Accordingly, geological mapping was commenced _in 1942 and continued each season to the present. To supplement this information, a survey of the water wells was carried on in conjunction with the mapping. However, to obtain more positive and evenly distributed structural control throughout the area as a whole and to define more adequately structural trends indicated by the preliminary mapping, it was necessary to resort to the use of drills to penetrate the glacial mantle. Various types of light drills are commonly used for this purpose and provide geological information in the form of drill cuttings, cores, drilling time rates, etc. Correlation of information is generally obtained through comparison of cored sections, drill cuttings, micro-fossils, and drilling time rates. However, in this case the holes were electrologged and correlations were made chiefly by comparison of such logs. The data so obtained is plotted and portrayed in the form of structure contour maps on recognizable stratigraphic horizons and in the form of isopach maps of the recognizable stratigraphic intervals penetrated in the holes. This method had not been widely used in Alberta previously and the technique employed was necessarily developed after the project began.

Jan 1, 1945

By R. H. Waddington

Historical The limitations of reverberatory furnace operation have prompted many investigators to consider electric furnaces for melting electrolytically refined cathode copper. In the majority of cases where experimental work was performed, the furnace used was of the granular resistor, induction, or indirect-arc rocking type, and attempts to adapt the three-phase direct-arc furnace to copper melting appear to have been relatively few. In 1935, the International Nickel Company of Canada, Limited, carried to an advanced stage its experimental investigation of continuous melting of copper in the three-phase direct-arc furnace, and demonstrated that this process was technologically and economically practicable. Trial operations were conducted at the Huntington, W.Va. works of the Company, and were followed by the installation at Copper Cliff, Ontario, in 1936, of a full-scale unit for commercial operation. Two years later, a second unit was installed -which raised the electric melting capacity to a point permitting complete replacement of the coal-fired reverberatory furnace operation in the production of refined copper castings.

Jan 1, 1946

By P. G. Killeen

Proper calibration of portable gammaray spectrometers and spectrometric logging equipment is essential if they are to be used for accurate quantitative determinations of radioelement concentrations. In the case of both types of equipment, it is necessary to determine the system calibration constants (stripping factors and sensitivities). In the case of borehole logging equipment, it is further necessary to determine the system response characteristics if the data are to be computer processed to improve the accuracy and resolution of the logs. Facilities are now available near Ottawa for the complete calibration of portable gamma-ray spectrometers and spectrometric logging equipment, in addition to already existing facilities for calibrating airborne gamma-ray spectrometers. Limited additional facilities are also available or planned in several other areas of Canada.

Jan 1, 1978

By A. S. Romaniuk

More than a decade ago, CANMET management recognized the need to make better use of existing technological information in mining and extractive metallurgy-two fields basic to the economic well-being of Canada. There were at that time no indexes or files dedicated to disseminating technical information for the many minerals mined and processed in Canada, including coal. CANMET, with the nation's largest research and library resources in the minerals field, was in a unique position to fill this need. Initial efforts were concentrated on building a mining file, beginning with identification of world sources of published information, development of a special thesaurus of terms for language control and adoption of a manual indexing/retrieval system. By early 1973, this file held 8,300 references, with source, abstract and keywords given for each reference. In mid-1973, operations were computerized. Software for indexing and retrieval by batch mode was written by CANMET staff to utilize the hardware facilities of EMR's Computer Science Centre. The resulting MINTEC file-one of the few files of technological information produced in Canada-is the basis for the national literature search service in mining offered by CANMET. Attention is now focussed on building a sister-file in extractive metallurgy using the system already developed. Published information sources have been identified and a thesaurus of terms is being compiled and tested. The software developed for CANMET's file-building operations has several features, including the selective dissemination of information and production from magnetic tape of photo ready copy for publication, as in a bi-monthly abstracts journal.

Jan 1, 1979

By R. J. Munday

Although uranium deposits in northern Saskatchewan are clustered around the Athabasca basin, basement lithostructure determines their distribution. Basal Wollaston Group pelites are invariably graphitic and carry uraninite in felsic segregations and biotitic pegmatite. Where these intersect the Athabasca Formation, remobilized uranium concentrated as pitchblende. Uranium is also concentrated in silicified and hematized sandstone where the Athabasca Formation overlies post-orogenic faults. Presumably, pregnant solutions associated with the fault were stripped of their metals as they emerged into the contrasting physico-chemical environment of the sandstone basin. Both these types of mineralization correlate with a Grenvillian (-1,000 m.y.) heating event and associated diabase intrusions. However, the rich pitchblende veins at Uranium City appear to predate the Athabasca Formation, but display spatial correlation with the Martin Formation. They are tentatively associated with a syn- to post-D3 retrograde metamorphic event which thoroughly leached crystalline basement and generated uraniferous fluids which escaped, and precipitated metals, into fractures associated with faults that define the grabens in which the Martin Formation was deposited. Remobilization events allowed some of this uranium to move upward into fractures within Martin sediments.

Jan 1, 1979

By R. C. A. Thurston

AT A FATIGUE SESSION organised by the A.S.T.M. in 1949, R. E. Peterson presented a brief introductory paper ( 1) in which lie referred to a discussion on the fatigue of metals which took place in England in 1849, and then proceeded to review some of the subsequent researches concerning the mechanism of fatigue. In the course of the review, he discussed metallograpl1ic studies with single crystals and polycrystalline materials, studies with X-ray methods, and the application of the electron microscope. During that hundred-year period considerable progress was made toward a better under-standing of the nature of fatigue, although it is probable that even greater attention was directed to the more practical aspects of the problem, such as the effects of notches, temperature, corrosion, surface treatment, residual stresses, and so on. Since then there has been an appreciable acceleration in the tempo of the fundamental work, partly influenced by the rapid development of the theory of dislocations, with the result that our knowledge of the mechanism of slip, the initiation of fatigue cracks, and their subsequent propagation, has still further advanced, although it is by no means complete as yet. The present paper is an attempt to out-line the more recent developments in these basic studies, to correlate them when possible, and to draw attention to those directions in which research might profitably be pursued.

Jan 1, 1957

By Tao Long

Recently, the great amount of funds has been invested in the reconstruction of damaged infrastructure and house of subsidence area of coal mine and mine reclamation. This is a benevolent and popular work, which is highly praised. However, because of complicated collapse area problems in China, especially the less integrated control research in the collapse area of metal mine, and the technological weakness, how to effectively control the subsidence area, restore landscape and ecological environment, and utilize the abandoned mine land, are major issue related to the mining area of sustainable development. The research situation about the formation of metal mine collapse area at home and abroad is reviewed, and then the effect of the collapse area on the mine safety and ecological environment, the existing technical problems and development direction are analyzed. Lastly, the technical measures of the collapse area control and cooperative underground mining is put forward.

Oct 1, 2010