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By Thomas J. Ferree

"IntroductionThe objective of this chapter is to provide important criteria relating to the operation and maintenance of spiral concentrators and Reichert cones, so that optimum performance can be achieved and maintained in a mill circuit. Little space will be devoted to the theory of the forces of separation or the technical details of the devices, as that in(ormation is available from other sources. The discussions in this chapter will be presented in a manner that should be interesting and useful to anyone who may be exposed to these methods of gravity separation. It is most important for the reader to understand that each application of the equipment should be considered on its own merit, as no two suites of minerals respond exactly alike in mineral processing circuits. The information herein should be useful as a guide toward increasing the metallurgical efficiency of the processes, irrespective of the type of minerals being concentrated.It is highly recommended that certain tools be made available to the personnel responsible for metallurgical performance of the spirals and cones; these include a set of standard type laboratory screens, a medium quality petrographic microscope, and a vanning plaque or gold pan. These devices, when used in conjunction with a basic understanding of the mill circuit, provide immediate knowledge on the characteristics of any sample in the mill circuit. The information gained by visual evaluation of sized fractions of products can solve many of the basic problems of mineral beneficiation, and at the same time increase the interest of the non-technical personnel associated with the plant operation. There are many problems associated with obtaining satisfactory performance from a mill operation. Many of the problems have to be solved using a technical approach. Some of the problems, however, can be solved with practical knowledge and common sense. It is hoped this chapter can provide a guide to both techniques."

Jan 1, 1989

By Paul Bedard, Réal Daigneault, Guy Perrault

"La mine Lamaque est située a Val d'Or, Québec; les roches hônes appartiennent au groupe de Malartic, partie supérieure, et sont des andésites et des pyroclastites. On y retrouve deux formes d'intrusifs; des petites cheminées (ca. 150 m D) et des dykes (ca. 10 m d'epaisseur). Les petit es cheminées contiennent:1 - des diorites et des tonalites (cheminées principale, est et ouest) d'affinité calco-alcaline: Zr 140 ppm, Sr 761 ppm, P2O5 0.31% et (La/Sm)n 3.0;2 - des diorites (cheminée 4) d'affinités tholéiitique: Zr 32 ppm, Sr 181 ppm, P2O5 0.27% et (La/SM)n 1.5.La diorite de la cheminée no 5 contient deux fractions, une de chacune de ces deux affinités. Les dykes tant de porphyre feldspathique quartzifére que ceux de prophyre feldspathique sont d'affinité calco-alcaline: Zr 83 ppm, Sr 500 ppm et P2O5j 0.10%.Le gisement de 10 mine 2 est filonien: veines subhorizontales (""flats "") surtout et veines sub-verticales dans des zones de cisaillement. Le dernier réajustement structural de direction de compression nord-sud a broyé le quartz des veines existant es et rendu possible leur minéralisation. Les veines minéralisées contiennent du quartz, de la tourmaline, de la calcite avec des traces de scheelite, de pyrite et d'or; elles sont bordées par de minces (2 à 20 cm) bordures d'altération où l'on retrouve un enrichissement en carbonate, paragonite, apatite, rutile, saphène et zircon et où les phases ferromagnésiennes sont disparues. On a documenté le migrations géochimiques suivantes:I - de la bordure d'altération vers l'éponte, K2O, Rb et MgO;2 - de l'éponte vers la bordure d'altération, Na2O;3 - de l'éponte vers la veine, SiO2.P2O5, TiO2, Zr, Y, Nb et CaO sont enrichis dans la bordure d'altération."

Jan 1, 1983

By Linlin Tong, Xiangling Song, Guobao Chen, Zhenan Jin, Hongying Yang

Biooxidation of a high arsenic-bearing refractory gold ore was investigated to determine the arsenic removal efficiency by the cultured bacteria and to examine the effect of biological pretreatment on subsequent gold cyanidation. The biooxidation pretreatment process utilizes the ability of adapted acidophilic bacteria to oxidize pyrite and arsenopyrite and release the encapsulated gold. The released gold can be efficiently extracted by the subsequent cyanidation process. The biooxidation experiments were conducted with cultured bacteria using various sizes of agitation tanks. Leaching results showed that over 96.26 % arsenic extraction could be obtained from this ore after 6 days of bioleaching with continuous stirred tank reactor (CSTR). Gold extraction during the cyanidation process was increased from 29.35% to 96.71% after biological pretreatment. The content of arsenic in the biooxidation residue was reduced to below 0.3%. The transformation process of As was considered as [AsS]2- ? As (?) ? As (?) during the biological pretreatment.

Jan 1, 2014

By H. Asgari, A. G. Odeshi, J. A. Szpunar

In the current research, the role of grain size on the texture formation and mechanical behavior of rolled AZ31B Mg alloy is investigated under shock loading conditions. The grain size of the original asrolled sample was 8 µm and different grain sizes, e.g. 25 and 46 µm, were produced by heat treatments at temperatures in the range of 400-500 °C. In order to evaluate the effect of grain size on the anisotropy of mechanical behavior, the samples were cut along the rolling direction (RD), transverse direction (TD) and normal direction (ND) and tested at strain rates of 900 and 1200 s-1 using Split Hopkinson Pressure Bar. Texture measurements showed that initial texture of the samples cut from the as-rolled sheet is a weak rtype texture. However, a stronger texture was observed for samples with large grains. After shock loading, a (00.2) basal texture developed in all samples and the intensity of the basal poles was higher in samples with coarser grains. This observation is corroborated by high twinning activity and possible activation of pyramidal <c+a> slip in coarse grained samples. Besides, the strength of basal texture increased with increase in the strain rate. Furthermore, the samples with larger grain size showed lower strength and higher ductility, and this was observed for all investigated strain rates.

Jan 1, 2014

By C. A. D' Odorico

The zinc pressure leaching (ZPL) plant at Teck Cominco&apos;s Trail Operations was started up in 1981 and represented the world&apos;s first commercialization of the technology. From the outset, the process was designed to operate using iron-rich Sullivan Mine zinc concentrate. When the Sullivan Mine reached the end of its life in 2002, the ZPL plant underwent a significant process change with the treatment of 100% Red Dog zinc concentrate. Through careful improvements to existing plant processes, controlled changes to plant operating parameters and a rapid adjustment to the modified process by operations personnel, the plant has been successfully converted to processing a feed of 100% Red Dog zinc concentrate. This paper discusses the challenges faced during the conversion and describes the modifications to plant operating procedures, as well as changes to plant processes.

Jan 1, 2004

By J. H. Sokolowski, R. I. MacKay

The level of Si and Cu in the 3xx series of alloys affects the volume fraction of the a-Al dendritic phase and the Al-Si eutectic phase. The volume fraction of these phases in turn affects the feeding conditions during solidification and ultimately the Area Fraction Porosity and Mean Pore Diameter measured in the as-cast structure. This work sets out to establish the relationship between the volume fraction of the a-Al dendritic phase and the Al-Si eutectic phase and the resulting porosity that forms on the Monotonic and High Cycle Fatigue properties. The alloys in question are the Al-9%Si-l %Cu and a Al-7%Si-4%Cu alloys which were cast into V8 performance engine block castings and then heat treated to achieve desired mechanical properties. The engine block castings provided the mechanical and metallographic test samples analyzed for this work.

Jan 1, 2006

By Unkown

To the Membership of the Institute Gentlemen: The Mineral Industry of Canada in 1948 The preliminary estimate issued by the Dominion Bureau of Statistics and tabulated in the Bulletin of January, 1949, indicated that the value of Canada&apos;s mineral production in 1948 reached an all-time high of $808,180,216, showing an increase of 25 per cent over the previous record of $644,696,007 established in the preceding year. The output value of metallics was increased by 22.4 per cent; of fuels, by 43.7 percent of other non-metallics, by 19 per &apos;cent; and of structural materials, by 16.8 per cent. The value of metals produced in 1948 at $483,770,759, was about $87,000,000 more than in the previous year. There were substantial increases in the tonnages of copper, lead zinc nickel, and other base metals produced, but the rises in market prices for such metals accounted for most of the gains in output values. Production of gold at 3,495,403 ounces valued at $122,339,105 indicated an increase in volume of approximately 500,000 ounces and an increase in value of 14 per cent. Despite the benefits provided under the Emergency Gold Mining Assistance Act 1948 the volume of gold produced in the year was still nearly 2,000,000 ounces less than the record of 5,300,000 ounces established in 1941. The value of mineral fuels produced in 1948, at $158,787,255, was 44 per cent above the 1947 total. Coal production at 18,431,250 tons valued at $107,298,757, while substantially higher than in the preceding year was still half a million tons below the record reached in 1942. Striking developments in the Leduc field in Alberta were responsible for bringing the output of crude petroleum in the year to a new high of 12,098,166 barrels, valued at $36,858,959.

Jan 1, 1949

"Acid resistant brick lined autoclaves and related vessels are utilized in pressure oxidation for the recovery of gold, copper, and other metals. The combination of the corrosion resistant membrane, acid resistant brick, mortar and steel shell is a composite system that requires a sophisticated stress analysis. In order to obtain meaningful results both the model and physical properties of the materials must be carefully selected. Evaluation of the calculated results requires an understanding of both the failure mechanisms of ceramics and experience with the performance of existing lining systems.INTRODUCTIONAcid brick lining systems are used in pressure oxidation autoclaves and related vessels to provide thermal and mechanical protection for corrosion resistant membranes that are applied directly to the interior of the vessel shell. The acid brick and mortar must be resistant to the process conditions and must provide a mechanically reliable structure.The construction of lined vessels incorporates a wide range of materials that can include the carbon steel vessel, austenitic weld overlay, lead lining, organic membrane, ceramic brick, mortars and other alloy components. The physical properties of the materials can vary by orders of magnitude and when combined in the construction of the lined vessel create a complex composite structure. The materials may be bonded together or act independently of each other. Stresses are induced into the lined vessel include pressure, thermal expansion, chemical expansion and mechanical loads.The complexity of these systems makes it is very difficult to account for all of the variables in the structural analysis of lined vessels. Historically calculations were simplified and designers primarily relied on experience with previous applications.The greatly improved tools for Finite Element Analysis (FEA) available today allow for detailed calculation of the stresses imposed on the vessel shell and lining. Koning & Lauzon (2004) presented a paper on design fundamentals including a discussion on the application of FEA methods at Pressure Hydrometallurgy 2004 in Banff. When a designer carefully constructs a model and selects the correct materials properties for the calculations, meaningful and useful results can be achieved."

Jan 1, 2012

By A. H. Lang

"IntroductionMUCH PROSPECTING, exploration, and development work was done for uranium in Canada in 1952, chiefly in northern Saskatchewan and in the Great Bear Lake region of the northwest Territories. The outstanding feature of the year was the great amount of work done in preparing for production at the Ace mine of Eldorado Mining and Refining, Limited, in the Goldfields region . of Saskatchewan. Many private companies and prospectors were also active in this region. Most of the other parts of Canada where uranium has been found received less attention than during the last few years, partly because so much interest was taken in the Goldfields region.In presenting this short summary of the year's activities now, the writer is handicapped because the season is not yet over; some discoveries have probably not yet been announced, and there has not yet been time to digest the numerous reports that have been sent in by companies and prospectors. In any case it would be impossible to give details for most of the discoveries and properties, because that would require a long report, and because that information is classed as confidential until released by the discoverers and companies concerned. It is only possible, therefore, to give a few generalizations, a brief out-line of the activities in northern Saskatchewan, even briefer ,accounts of the work in other parts of the country, and a few details that property owners have informed the writer he may publish or that have already been published by the owners."

Jan 1, 1953

Discovery of an economic diamond deposit produces considerable wealth in terms of jobs, royalties, mining investment, and economic spinoffs for residents, including Aboriginal peoples. Diamond mines contribute to the GDP, increased personal income per person and reduced unemployment rates. Is it possible in Alberta?

May 1, 2008

By C. Blawert

In spite of various corrosion studies on HPDC AZ91, there is no clear indication which microstructure gives the best corrosion performance. The skin with its fine microstructure is sometimes reported to have the best corrosion resistance, but there is no clear definition of the skin. If the skin is the outermost part of the casting and nothing is removed from it, then it is contaminated and the corrosion resistance is low. If the outermost skin is removed (about 25 µm) then a better corrosion resistance can be obtained. However this does not automatically mean that there is no other region in the bulk of the casting which could have a similar or even better corrosion resistance. Indeed, the corrosion measurements including potentiodynamic polarization and long term electrochemical impedance spectroscopy (EIS) revealed a lower corrosion resistance of the original as-cast skin about 100 pm thick. The thickness of this region is more or less independent from the thickness of the casting section. The surface region is free from any dendritic grain growth which influences the amount and distribution of the 13-phase and therefore the distribution of the most important alloying element Al. This could explain the different corrosion behavior. Further reason can be found in the enrichment of some impurities such as Fe in the near surface.

Jan 1, 2006

"Ore deposits containing rare earth elements normally contain small amounts of the radioactive elements thorium (Th) and/or uranium (U). These are the naturally-occurring isotopes U238, U235, and Th232 (and associated decay-series daughter products) that are ubiquitous in nature, and that contribute a small percentage of the natural background radiation exposure encountered by humans. The presence of these radioactive materials in the ore deposit creates potential hazards to human health and the environment that must be dealt with properly in the mining, processing, and refining of the ores, as well as management of waste streams and residues. This paper presents an overview of the environmental and safety issues associated with U and Th, with particular emphasis on rare earth mining, processing, and refining projects; the regulatory approaches followed to ensure that rare earth deposits are developed, operated, closed, and decommissioned safely; and the development of information during the project predevelopment work and permitting processes that feed into the design, operation, and closure of tailings impoundments and milling/separation/refining facilities. Case studies will be presented subject to the availability of relevant public information. INTRODUCTIONNearly all ore deposits containing economically-recoverable rare earth minerals also contain small amounts of the radioactive isotopes for the elements thorium (Th) and/or uranium (U) and their associated radioactive decay products. Therefore, the handling and management of these materials in mining and mineral processing operations must be performed so that workers and the environment are protected from harm from Th and/or U (and their radioactive decay products), just as they must be protected from any other potentially harmful constituents present in the ore or introduced in processing. Examples of these might include ores with high sulfide content, which may pose a risk of acid rock drainage, or chemicals used in ore processing and metals production.The purpose of this paper is to present information on how rare earth mining and processing projects with ores containing Th and/or U can be developed, operated, and decommissioned safely according to applicable regulations intended to protect worker health & safety and the environment.It should be noted that some countries are considering developing Th as a feedstock for producing nuclear energy, which could have some effect on future development of rare earth ore deposits. To avoid confusion, that issue is not discussed in this paper."

Jan 1, 2012

By S. F. Featherby

"This paper traces briefly the historical development of coal handling systems to meet the needs of a rapidly developing thermal power generation technology. The wide range of operating requirements is demonstrated by comparing and contrasting the Wabamun GS of Calgary Power Ltd. and a typical modern Ontario-Hydro thermal plant. The problems of safe storage of large tonnages of coal in stockpiles are discussed, together with recommendations for stockpile management. The development of coal bunkers and their management is discussed in detail, together with future trends in the industry."

Jan 1, 1966

"THE CONCEPT of energy as a commodity, while not entirely new, is not as widespread as the importance of the idea to this modern world would lead one to expect. The growth in the supply and use of energy over the past years has been tremendous, but our very closeness and familiarity have somewhat distorted the viewpoint, particularly of the younger generation. To many of us who remember the wonderful satisfaction of our first responsibility for directing two horsepower hitched to a farm cart or hay wagon, there still arises a feeling of some awe at the casual flick of the switch with which our sons and daughters summon to their convenience the service of some one hundred or more horsepower.Energy is the vital component of our existence and, no matter what contempt our day-to-day familiarity may •breed, it is wise to .pause from time to time and consider our national energy standing. Have we still capital in the bank? Are our expenditures wisely •conceived and well directed? Is provision being made for the years •ahead for the needs of our children and our children's children?"

Jan 1, 1953

By David S. Robertson, Richard F. Douglas

"Uranium is a lithophile element of relatively low natural abundance. Concentrations of uranium form through processes of erosion and sedimentation, and over 90 per cent of the western world's uranium ore reserves are in sedimentary rocks.Proterozoic quartz-pebble conglomerates contain about 60 per cent of the known uranium reserves. These are all similar in appearance, in mode of distribution and in manner of origin. They carry uranium minerals and/or gold and abundant pyrite. Their unique distribution in Huronian time required a pre-existing crust well enough evolved to have plentiful quartz and abundant gold, uranium and pyrite. The materials of value were deposited as detrital heavy minerals prior to the appearance of an oxidizing atmosphere in late Proterozoic time.Epigenetic uranium deposits occur in arkosic sedimentary rocks through the entire geological column. About 30 per cent of the western world's known ore reserves are in _these rocks. This type of deposit is particularly prominent in semi-arid parts of the United States, having yielded most of the uranium ore produced and containing nearly all of the known reserves.The Western States type"" of deposits occur in lenticular, permeable stream-laid sedimentary rocks. The de-posits are believed to have been precipitated from moving ground water at locations where plant debris or other organic matter had accumulated. The uranium may be derived from volcanic sediments, which are commonly associated with the units containing the ore, or it may be leached from exposed granite surfaces or from granitic debris which forms the sediments.A significant part of the world's uranium resources are in black shales and lignitic rocks. The lignites that contain uranium are virtually valueless as potential sources of heat. Uranium concentrations at levels such as to be potential sources of by-product uranium occur in many phosphorites.Reworked sediments may provide uranium in pegmatites and vein-like deposits."

Jan 1, 1970

By Charles J. Zablocki, Robert J. Kamilli

"Buried, possibly mineralized granite cupolas at the Silsilah tin deposit in Saudi Arabia (lat. 26°06&apos; N, long. 42°40&apos; E) have been successfully located using a closely spaced electric-field-ratio profiling technique. In this study, electrical fields at 27 and 270 Hz across grounded electrodes spaced 50 m apart were measured along six traverses. This method is interpretable by inspection, unlike the dipole-dipole technique, which requires mathematical modeling for interpretation.In the study area, the technique allowed the authors to identify and distinguish among unroofed granite cupolas, cupolas with their aplite-pegmatite apical contact zones intact, strong (quartz-rich) and weak (relatively quartz-poor) greisens, dikes, faults, and pervasively argillized rocks.This method should be useful in the valuation of other shallow mineral prospects in similar settings in other parts of the world, especially deposits for which the location of vertical contrasts is important, such as veins or mineralized zones associated with the apexes of small igneous cupolas."

Jan 1, 1993

By Staff

The Tetreault mine, operated by the British Metal Corporation (Canada), Limited, holds a unique position in Canadian mining, being the only steady producer of zinc in Canada east of the Rocky mountains. Its importance in Canadian zinc production may be gauged with some accuracy, since, in 1927, it was responsible for over 13 per cent of the zinc output of the Dominion. In addition, it also made valuable contributions to the production of lead, silver, and gold. Location: Situated in the foothills of the Laurentian mountains, 600 feet above sea level, 20 miles from the St. Lawrence river, and 52 miles due west from the city of Quebec, the property is in the township of Montauban, county Portneuf, Province of Quebec, as shown in Figure I. The municipality of Montauban, immediately adjoining the mine, has a permanent population of 700 people and is six miles by road from Notre Dame station on the main line of the C.N. Rys. between Montreal and Chicoutimi-Notre Dame being n6 miles by rail from Montreal. Connection by 19 miles of dirt-and-gravel road with the Provincial highways&apos; system of Quebec Province, the city of Quebec, which is distant 78 miles, can be reached by automobile in less than three hours, while the distance to Montreal by road is 16o miles .

Jan 1, 1928

By J. Laganiere

A considerable part of the sulphuric acid requirements of the Aluminum Company of Canada&apos;s Arvida smelter comes from the burning of 180-200 tons per day of zinc &apos;"&apos;sulphide concentrates in a 22-ft.-diam-eter fluidized bed roaster. The plant and its operation were fully de-scribed in a publication that appeared about ten year ago (1). A simplified flowsheet of the roasting and gas-cleaning sections of the plant is given in Figure 1. The wet zinc sulphide concentrates are un-loaded into a pug mixer, by means of a Pay loader, and mixed with water in a mixing tank to make a slurry of 80 per cent solids. The slurry is transferred to a .feed tank and then introduced into the roaster at a point four feet above the constriction plate, which is the height of the settled bed of zinc calcines. The roasting temperature is con-

Jan 1, 1963

By Thomas G. Madgwick

Introduction Development of oil and gas is still centred in the Province of Alberta, much as it was when C. C. Ross read a paper on this subject three years ago at the Annual General Meeting in Montreal; but so far as gas is concerned, its early production in Saskatchewan seems now assured. The three years that have elapsed since Mr. Ross&apos; paper have witnessed a growth in the world&apos;s production of oil that has created a potential supply out of all proportion to the demand for petroleum products, and one that has resisted the most energetic efforts of the industry entirely to control. The natural result has been very much to retard the active prospecting of new structures in the Prairie Provinces with any immediate view to oil production, although the same factor has not hindered the search for gas to the same extent. One consequence has been to divert the attention of organized oil operators from wildcat drilling to more detailed geological investigation than had hitherto been customary, sometimes accompanied by test drilling with a view to the elucidation of geological structure rather than to the immediate development of production which at the present is not needed. Nevertheless, in spite of the growth of this phase of oil prospecting - which the writer would be the last not to welcome as a very real blessing and of far greater value than indiscriminate wildcat drilling in either the complex structures of the foothills or the simpler but largely concealed formations of the plains- it is most satisfactory to have to record that in these three years the growth of production both of naphtha and the heavier crude-oil has kept pace with the by no means inconsiderable growth in the production and utilization of natural gas.

Jan 1, 1929

By T. W. Wlodek, Zygmunt Kowalczyk

In the period from 1946 to 1964, the annual output of co al from Polish mines increased from 4 7.3 to 117.35 million tons. In this paper, the methods of bringing about this increase in productivity through the building of some twelve new collieries (producing some 15 million tons annually) and the modernization, reconstruction and extension of some thirty-six older collieries are discussed.

Jan 1, 1967