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By M. G. Rylatt, G. M. Popplewell

"Production from Canada's first diamond mine is planned for the last quarter of 1998. The climatic conditions and the variation in kimberlite types to be treated have lead to the development of a compact and flexible processing plant.High kimberlite moisture contents and winter temperatures below -40°C have dictated a process flowsheet with limited in-circuit storage to reduce materials handling difficulties. The latest developments in High Pressure Grinding Roll technology will be used to liberate the valuable diamond, reduce diamond breakage, and increase fines production to reduce the amount of material for down stream processing in the Heavy Medium Separation section.A varying heavy mineral concentrate yield has lead to the development of a final Recovery section that will incorporate Attrition Milling and Wet High Intensity Magnetic Separation for concentrate reduction. The latest developments in diamond X-ray sorting will be used to produce a final diamond concentrate for mechanical sizing, weighing and packing.Fine tailings thickening will utilise Deep Bed Compression type thickeners. This relatively new technology can produce;i) high underflow densities at low flocculant dosage rates, andii) clear overflowswith a smaller thickening area than conventional high-rate thickeners."

Jan 1, 1998

By W. K. Chan, R. Lahaie

"The Suncor Oil Sands Mine located north of Fort McMurray, Alberta, produces about 80000 m' per day of tailings waste which must be disposed of economically in an environmentally acceptable manner. To date, this has been accomplished by impounding the high water content tailings wastes behind large dykes, many of which approach 100 m in height .The dykes are constructed using suitable overburden material stripped prior to the mining of the oil sands feed and/ or the coarse sandy fraction of the tailings waste itself. Although the above is common practice at many mining operations, the large volumes handled and the resultant costs require designs to be meticulously fine-tuned toward the optimum. As a result, considerable effort is expended on planning, designing and construction, and performance monitoring. The lack of precedent experience (Suncor pioneered oil sands mining), coupled with the realities of long, harsh winters and a variety of troublesome site conditions and construction materials, has led to some very unique dyke construction.This paper overviews current tailings disposal plans as welt as some of the key issues related to the design, construction and performance of these large dykes."

Jan 1, 1988

By George B. Saunders

It is the purpose of this paper to point out conditions as they exist in the merchandizing of coal, to compare these conditions with methods in use by competitive producers of coal substitutes, and to present briefly some suggestions which may help the individual operator to market more coal in the immediate future, while we are waiting for the scientist and research worker, who are now busy on coal betterment , to produce in a practical way the results which they now write about in such glowing terms. While it may be unnecessary to call the attention of coal operators to the present deplorable condition of the industry, it might be well to impress upon our members in other branches of mining, as well as upon the public at large, the seriousness of the situation. Emerging from the war and the period of reconstruction that followed, the coal industry found itself with too many mines and too many men for normal conditions. To make matters worse, the interruptions in deliveries caused by strikes, the unfavourable publicity caused by socialistic propaganda, and the repeated governmental investigations, made the market a fertile field for coal substitutes which were not so handicapped. These substitutes were well advertised, and were marketed in an up-to-date manner, furnishing an example from which the coal operator could well profit. Now, whether or not there is agreement as to the cause or causes of this condition, there can be no doubt that we are today face to face with the fact that the sale of coal has not kept pace with the sale and use of other commodities. Had it done so, we would ere this have been able to take care of the surplus labour and work our mines at least approximately full time.

Jan 1, 1929

By A. Ehsani

"Seas and oceans constitute about 70% of the earth’s surface. They contain an enormous stock of various mineral resources such as sedimentary (marine placers), massive sulfide ore deposits, manganese nodules and cobalt-rich ferromanganese crusts. Sea and ocean floor ore deposits could well contribute to the meeting of ever-rising demand for raw materials in the metal industry. In this regard, more research and development in science and technology appear to be required to ensure maximum benefit from the mineral resources of seas and oceans. Since the 1960s, a variety of mineral and metallurgical processes have been studied and developed to deal with marine ores and to extract metals such as gold, nickel, copper, cobalt, manganese, tin, platinum group metals (PGM), zirconium, thorium, etc.In marine environments, there are many parameters which can affect the selection of the mineral and metallurgical processes. These include the extent and grade of the deposit, mineralogical and chemical properties of the deposit, and physical properties of minerals present with particular reference to particle size distribution and mineral liberation size.In this paper, we briefly review the latest trends in processing and extraction of marine mineral resources. Mineral processing technology is mostly applied for recovery of precious metals i.e. gold and PGM, in particular, from marine placers. In general, pre-treatment (sizing, classification, dewatering), gravity concentration techniques (shaking tables, spirals, jigs, etc.,), flotation, magnetic, and electrostatic separation are the options for enrichment of marine placer ore deposits. In the case of massive sulfides, manganese nodules/cobalt-rich crusts, hydrometallurgical and pyrometallurgical methods (as proven technological methods) can be exploited for extraction of metals from concentrates after physical separation or directly from marine ores. The hydrometallurgical treatments involve acid (e.g., sulfurichydrochloric) and alkaline (e.g., ammonia) leaching with different reducing agents and pre-treatments such as roasting. Alternatively, pyrometallurgical treatments involve mostly smelting, chlorination and segregation processes."

Jan 1, 2016

By M. C. Harris

"Excess Gibbs energy is a thermodynamic parameter which quantifies the difference between the value of the Gibbs energy for a real mixture and that for an ideal mixture. More specifically the partial molar excess Gibbs energy of a species (i) in a mixture is indicated by the change in the overall excess Gibbs energy of the solution as the number of moles of species (i) changes while keeping temperature, pressure and the number of moles of all other species in the solution constant. Generally it is obtained from the activity coefficient which in turn can be obtained for a species in a mixture using a variety of models. The most widely used method is to use UNIFAC. Flotation is probably the most important process in the concentration of minerals and requires the use of reagents such as collectors and frothers. There is abundant experimental data which illustrates that collectors of different alkyl chain lengths will change the contact angle and that frothers of different structures and molecular weights will result in changes in key flotation properties such as froth behavior, surface tension and critical coalescence concentration. In this paper it is shown that there is a strong linear relationship between measured parameters such as froth volume/height, surface tension, critical coalescence concentration and contact angle and the partial molar excess Gibbs energy of the molecules used. Proposals are made to explain these correlations.INTRODUCTIONAs is well known froth flotation is arguably the most widely used process in the separation of minerals. In broad terms the process relies on the use of reagents known as collectors to adsorb onto a mineral surface and thus render the mineral particle hydrophobic. Alkyl thiolates are very commonly used for this purpose. The hydrophobicity is induced as a result of the alkyl group’s molecular structural properties which results in it forming a non-ideal mixture with the process water. Surfactants (or frothers) are typically alcohols and are known to lower the surface tension of the system and also inhibit bubble coalescence and reduce bubble size. Since alcohols are polar they will also form a non-ideal mixture with water. The hydrophobic mineral attaches to the bubble and rises to the froth phase where the valuable mineral is recovered as a concentrate. Frothers have often been characterized using the so-called HLB (hydrophobic-lipophilic balance) number but recently it was shown that the use of activity coefficients (?) or excess Gibbs energy (G ex ), which is calculated using equation (1) is a much more appropriate way to describe the behavior of these reagents in non-ideal mixtures with water (Corin and O’Connor, 2014)."

Jan 1, 2016

By S. Kashani-Nejad

The formation of oxides during the dehydration of MgC12,6H20, Bischofite, was studied by heating the bischofite over a range of time and temperatures in ambient atmosphere. Using a methanol-leaching technique developed by authors, the oxides that formed were isolated, identified and assayed. Three distinct regions of oxide stability were identified. The oxide produced at dehydration temperatures less than 300 °C was Mg2(OH)3C1,2H2O; at 300 °C, mixtures of MgOHC1 and Mg2(OH)3C1.2H2O were formed and at 400 °C, MgOHC1 was the only oxide produced. The presence of MgO observed in the products of the dehydration of bischofite at temperatures above 400 °C was due to the thermal decomposition of the MgOHC1 that was formed while the sample was heating to over 400 °C.

Jan 1, 2006

Despite the claims of energy efficiency and the considerable development that has gone into dramatically extending rolls? life and facilitating rolls? change-out, in the six years since the last SAG conference, only a few HPGR operations have entered the realm of mineral processing. Risk barriers to the take-up of new equipment or processes are: a massive increase in materials handling issues as well as in the number of pieces of equipment required, low total circuit potential energy savings, and similar or higher capital costs. An alternative route is to make use of the complementary strengths of the HPGR and SAG in hybrid circuits. Minimising materials handling issues, providing an ideal balanced feed to the AG or SAG mill, and improving controllability through shifting grinding load as the RoM feed changes, are all potential major advantages to this approach. Conceptual circuit layouts, based on real measured ore and equipment data, are presented here to illustrate the potential production upside, the reduction in operating costs and the reduction in the physical and energy footprints.

Jan 1, 2012

By P. R. Cook

Thunder Bay Terminals' plant, now in operation, cost about 70 million dollars and was completed on time and under budget. The paper is the project manager's account of this accomplishment. From site selection through feasibility, engineering and construction to realization, he emphasizes the necessary philosophies for the control of time and money. The computer as a tool is discussed, as well as techniques for procurement.

Jan 1, 1979

By E. W. Mountjoy

THE Exshaw formation is a thin but very persistent black shale unit generally well exposed along the easterly scarp faces of the fault blocks comprising tl1e front ranges of the Rocky mountains. It is over lain by the Mississippian Banff shales and silty shales and underlain by the massive Palliser Limestone formation of late Devonian age. The Exshaw continues eastward under the plains of Alberta and on into Saskatchewan, with little change until it reaches the surface of the Palaeozoic-Mesozoic unconformity. During the summer of 1953, the writer was working- with a field party under Dr. J. L. Usher in the front ranges of the Alberta Rocky mountains. This party, sent out by the Mobiloil Company, conducted a geological survey of Devonian rocks between the towns of Banff and Jasper. The writer helped to describe and map these Devonian rocks and obtained first-hand information concerning the Exshaw shale and its relationship to the underlying and overlying sediments. Additional information was obtained from reference material and from a number of geologists whom the writer has consulted. Grateful acknowledgment is offered to them, to the Mobiloil Company for releasing field information, and to F. W. Beales and W. P. Hancock who helped edit the original paper for publication. Information from areas north and smith of that studied and from bore holes on the prairies is referred to. Localities mentioned may be found in Figure 1.

Jan 1, 1956

By Kyeong Woo Chung, Ho-Sung Yoon, Jyothi Rajesh Kumar, Chul-Joo Kim, Sung-Don Kim

The aim of the present study is to investigate the extraction, separation and recovery of the indivisible metals of dysprosium and neodymium from permanent magnets scrap leach liquor solutions with meaningful recovery. The present experimental development focused on dysprosium separation from neodymium and recovery by suitable mineral acids. Fundamental studies of the effect of time, pH and extractant concentration on the metal separation were conducted followed by proposal of a mechanism for extraction. Process development included generation of McCabe-Thiele diagrams and counter current extraction (CCE) studies. After loaded organic generation from the CCE process, this was followed by scrubbing studies as well final recovery of dysprosium.

Jan 1, 2014

By W. G. Scott

IT IS APPROPRIATE that your Institute should have chosen, for its 1956 Annual General Meeting, the Capital City of a province which is making such rapid advances in mining. The railway industry is proud to be playing an active role in this development, expenditures on equipment and railway construction in the Province of Quebec alone in recent years being in ?excess of a quarter of a billion dollars. In looking up some background material for this address I ran across a definition of a mine by Mark Twain, the great American humorist, which I thought might amuse you. He said that a mine was "a hole in the ground owned by a liar". I am sure that if he were alive to witness the enormous value attached to Canada's mineral resources today he would quickly change his definition. Canada's postwar record of mining development has been staggering in its variety and enormity. Historically, only the ?construction of our transcontinental rail ways outranks the largest of three of these development projects - the aluminum undertaking at Kitimat; the Quebec-Labrador iron ore deposits ; and the petroleum and natural gas developments in Wes tern Canada.

Jan 1, 1956

By W. F. Harkness, D. Hodgkinson

"A non-destructive testing program was established at Crows Nest Resources (C.N.R.), Line Creek mining operation following an in-service fatigue failure of a front wheel spindle on a large haulage truck.This failure identified a definite need for improvements in the ultrasonic techniques used during the mandatory spindle integrity examinations. Initial investigations using common mining industry ultrasonic examination techniques showed that the smallest detectable cracks were 75 mm in length for the spindle types in service at the C.N.R. site. The Initial findings indicated that inadequate inspection technique design was the cause of the poor performance. To improve inspection reliability it was identified that improved ultrasonic techniques were required. Results using designed ultrasonic techniques were encouraging, with the detection of simulated and natural cracks 12 mm long achieved. The cost benefits associated with the extended spindle life, following the removal of these small fatigue cracks, far exceeded those of the expertise and effort necessary to implement and conduct the N.D.T. program.Introduction During 50 years of evolution, non-destructive testing (N.D. T.) has progressed from a laboratory curiosity to a well accepted and invaluable tool used in the assessment of material integrity. Unlike destructive testing, N.D.T. does not deform or render the material useless. Non-destructive tests may involve many applications, from the determination of a corrosion prevention coating thickness to the examination of a raw material for internal and external deformities.Within the mining sector, highly-stressed components will normally have been subjected to some form of non-destructive test during their manufacturing cycle. These tests are used to ensure the component does not contain material flaws whichmay be detrimental to its service performance.While the component may have assured quality when produced, deterioration by fatigue may occur during an aggressive service life. Large dynamically-loaded components such as haulage truck front wheel spindles are , in particular, prone to this service related problem."

Jan 1, 1987

By B. A. Sparkes, J. H. Reeves

"The St. Lawrence Granite hosts vein-type fluorite mineralization that was mined until 1977. Recent drilling identified a significant fluorite-bearing structure hosted in adjacent meta-sedimentary country rocks. Several phases of vein fill and brecciation indicate there are three phases of fluorite mineralization, of which the later two phases are volumetrically significant. The earliest fluorite is purple and occurs along joint and fracture surfaces, in fault-breccia matrices, and as stockwork veins. The second phase comprises primarily red, yellow, blue-green, and white colours of fluorite. The latest phase is green with lesser clear fluorite. Identification of fluorite veins in the meta-sedimentary rocks opens up new areas for exploration.RÉSUMÉ Le granite St. Lawrence contient une minéralisation filonienne de fluorite, laquelle a été exploitée jusqu’en 1977. De récents forages ont permis d’identifier une structure importante contenant de la fluorite encaissée dans des roches métasédimentaires adjacentes. Les nombreuses phases de remplissage de filons et de formation de brèches indiquent qu’il y a eu trois phases de minéralisation de fluorite et les deux dernières sont importantes d’un point de vue volumétrique. La plus ancienne fluorite est mauve et se trouve le long de surfaces de joints et de fractures, dans les matrices de brèches de failles et en tant que stockwerks filoniens. La deuxième phase comprend surtout des fluorites de couleurs rouge, jaune, bleu-vert et blanc. La fluorite de la plus récente phase est verte avec des quantités moindres de fluorite claire. L’identification des filons de fluorite dans les roches métasédimentaires ouvre de nouveaux secteurs pour l’exploration."

Jan 1, 2016

By Larry G. Twidwell, Corby G. Anderson, Camille M. Fleuriault

"The selective precipitation of iron as ammonium jarosite is a well-established industrial technology in base metals hydrometallurgy. It is a key technology in minimizing iron tenors which would be disruptive to downstream processing. It also provides a more readily filterable iron solid to better facilitate materials handling. This paper elucidates the fundamentals behind industrial iron precipitation. Then, the details of the successful optimization of an industrial ammonium jarosite circuit are presented.HYDROMETALLURGICAL IRON REMOVAL FUNDAMENTALS Iron is the fourth most abundant element in the Earth’s crust (5% by weight) and is often found in complex ores such as sulphide-bearing formations. Iron represents an issue though during leaching, a technology which is widely used for the treatment of this type of ore: •,Iron has the particularity of forming hydroxides when leached under certain conditions. Iron hydroxides form a viscous gel, which is difficult to filter and traps valuable elements such as silver. •,Iron is solubilized along with other metals and interferes with the subsequent extraction steps. As a result, purification of the pregnant leach solutions is required to achieve economical extraction of base metals. In the 1960s, metallurgists developed iron precipitation processes for solution purification (Habashi, 1999). Nowadays, precipitation of iron bearing species, such as goethite, hematite or jarosite, has become one of the most common methods used in the industry to purify leach liquors. To be suitable, the precipitate has to be readily filterable and thus must not be too fine of particle size. Precipitation can take place in autoclaves at medium to high temperatures, under an oxygen or air overpressure (Tourre, 1984, Fleuriault 2016, Fleuriault Anderson Shuey, 2016))."

Jan 1, 2016

By R. W. Thompkins

"PREFACEPart 1 of this paper, published in the September issue, covered the occurrence of uranium, radiation from uranium ores, the uranium series, radioactive theory, radioactive equilibrium and application to the radon series, the working level, the theory of emanation and diffusion, transport by thermal diffusion of radon emanating from porous rocks, and definitions.The October issue carried Part 2, which dealt with radiation theory applied to uranium ores, other radon migration factors, factors affecting the radon gas release rate, the measurement of radon gas emanation rates, the tunnel concept, variation of emanation rate with grade and estimating radioactivity from grade analysis.Part 3, in this issue, concludes the series by discussing the techniques for controlling radiation and providing some example calculations.17.0. Techniques for Controlling Radiation17.1. Altering the Factors In the Diffusion EquationIt has been noted that radon gas emanates from the surfaces of exposed ore to the mine atmosphere. The diffusion laws establish the rate of this flow. The fundamental relationship is that the rate of flow (J) is a function of the pore concentration and the distance from the surface. It is expressed as: []If any of these terms is varied, either naturally or artificially, the rate of gas emanation will be altered.Altering the Diffusion CoefficientThe literature describes many ways to lower the radon gas emanation rates which are dependent on changing the diffusion coefficient:1. A layer of ice on top of a tailings dam or on a soil.2. Humid clayey materials and swamped soils over a radon source."

Jan 1, 1982

By Ursula M. Franklin

Old iron nails are one of the most common objects which entice the general public to ask questions about the history of metallurgy. There is a lot of history in old nails - history of the manufacturing industry, and social and economic history. Nails, therefore, are fine teaching tools; whether students have to acquire metallurgical skills or explore the structure and properties of wrought iron, whether they want to look into the history of inventions and the development of machinery, studying nails tells a story better than any teacher or any book. I have used this approach often and the following note is based on several student projects, particularly the work of Carmina Herrero and Vicky Marchant. Nails, those essential metallic fasteners, have long been with us. Their size, shape and design is basically a compromise between the makers' ability to control and manipulate material and the demands of the intended application. There were copper and bronze nails in antiquity, but in this paper I want to deal only with iron nails. In Rome, iron nails were common, and Cleere carried out the fine metallographic investigations on a large stock of nails recovered from a Roman fort site in Scotland. Those nails were hand forged; sorting them at the site on the basis of length, shape of head and shape of shank (in cross section) indicated that there seemed to have been some nail standardization. It appears that the Roman smiths used a series of heading dies starting with a 1/s-in. size. Each successive size increased by approximately 1/16-in. The metallographic inspection of the microstructures of the nails showed that the smaller nails were made in the one operation; i.e. both the tapering and the formation were accomplished on the heated rod without reheating. However, in the case of the larger nails, the nail had to be reheated for the tapering after the head had been forged. Most nails were tapered on all four sides of the shank and the shanks were square in cross section; only one group had rounded shanks. Most heads were flat disks, but in one group the heads were pyramids and another group had conic heads. Figure 1 shows the procedure used to produce the pyramidal heads. Obviously, Roman nail making was sophisticated and each nail design was meant for a particular use.

Jan 1, 1999

By J. Lammers, D. Adams

Most pressure oxidation operations introduce oxygen through a large multi-use nozzle in the vapour space of the autoclave. Sparge pipes extend inside the vessel to the point of discharge below the compartment agitator. However, two zinc pressure leach operations have successfully used a bottom entry oxygen sparge system for a number of years. Recently, the concept has been used in a whole ore gold pressure oxidation operation as well as a copper pressure leach plant. Both of the latter operations also introduce cooling water for temperature control through the same sparge pipe. This paper addresses the benefits of the bottom entry system with regards to autoclave performance and the positive effects on agitator performance.

Jan 1, 2004

By I. C. Christopher

Introduction The geology of the Cochen-our Willans gold mine has been described in reports by the late Dr. H. C. Horwood (1) in 1940 and by Dr. J. P. Nowlan (2) in 1947. Information from these and other (unpublished) reports has been incorporated in the present paper, together with some recent ideas regarding structural features which are at present being used to locate ore shoots. Location and History The mining claims of Cochenour Willans Gold Mines, Limited, occupy 705 acres in Dome township, on the east shore of Red lake opposite McKenzie island. Adjoining properties are those of McKenzie Red Lake Gold Mines on the west, Boymar Gold Mines on the north, Marcus Gold Mines on the east, and Martin-McNeely Gold Mines on the south. The claims of the original group were staked by W. M. Cochenour, Dan Willans, and H. G. Young, and the Cochenour Willans Syndicate was formed in 1928. Work was carried out by the Syndicate and several other companies during the next eight years with inconclusive results, due to the irregular occurrence of the ore. In 1936, Cochenour Willans Gold Mines, Limited, was incorporated and production was finally started late in 1939.

Jan 1, 1951

By John S. Stevenson

THE Twin "J" Mine, operated by Twin "J" Mines, Limited, represents an amalgamation of the old Lenora, Tyee, and Richard III mines (see Figure 1) on mount Sicker, eight miles by road, northwesterly, from the city of Duncan, on Vancouver island. These mines produced 253,000 tons of copper-gold ore between 1898 and 1909 (see Table I). During the more recent period of production from these properties, July, 1943, to May, 1944, Twin ?J? Mines, Limited, mined and milled ore with values mainly in copper and zinc, and minor values in gold, silver, and lead. Figures are not available for this later production. Field work at the property was started by the writer in 1941 and continued in 1943 and 1944.

Jan 1, 1945

By N. A. Duke, R. L. Carpenter

Abstract - The West Meliadine area is underlain by structurally interleaved panels of mafic and minor ultramafic metavolcanic rocks and metasedimentary rocks that occur along the northern margin of the Neoarchean Rankin Inlet greenstone belt. Three structural and metamorphic domains are recognized: (1) the easterly Wesmeg domain; (2) the central Barracuda-Ridge domain; and (3) the westerly Peter Lake domain. The Wesmeg domain is characterized by a series of southeast-trending, north-dipping, foliation-parallel panels of greenschist facies mafic metavolcanic and metasedimentary rocks. The Barracuda-Ridge domain is comprised of greenschist to amphibolite facies mafic metavolcanic rocks that define an east-northeast-trending structural grain. The Peter Lake domain consists of amphibolite facies mafic metavolcanic rocks and minor metasedimentary rocks intruded by a monzonite pluton. West Meliadine hosts the economically significant Wesmeg gold deposits, as well as other important gold showings across the Barracuda-Ridge and Peter Lake domains. The geological setting of the Wesmeg gold deposits resembles that of a break or fault zone. The Pyke Break is a major geophysical discontinuity (>65-km strike length) and is the first-order structural control on gold mineralization at West Meliadine. It is several kilometers wide and characterized by polyphase deformation and shear zone development accompanied by lode-gold mineralization. In general, gold concentration is related to quartz and iron-carbonate veining, iron sulfides (mainly arsenopyrite and pyrrhotite), and accompanying silicate alteration minerals that overprint favorable chemical and structural traps late in the history of deformation.

Jan 1, 2004