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By S. Nikolic

"Calcium ferrite slags are currently used in a number of copper-converting processes. Despite the industrial importance of this system the phase equilibria have not been fully investigated. Characterization of this slag system is necessary to improve the control of process parameters, including fluxing and operating temperatures. Recently, a modified experimental method has been developed; this involves rapid quenching of slag samples equilibrated at high temperatures with the resulting phase assemblages analysed using electron probe microanalysis (EPMA). In the present study, experiments were completed under controlled temperatures and oxygen partial pressures using CO/C02 or H2/C02 gas mixtures. The investigated slags were supported during equilibration by a substrate of the primary phase. This technique removes the limitations arising from the use of crucibles and facilitates rapid quenching of the melt. Experiments were carried out at 1200°C and 1250°C (1473 Kand 1523 K) and in the composition range 0-40 wt.% Cu20, 0-25 wt. % CaO and 45-80 wt. % Fe203. Liquidus and solidus data are reported for the primary phase field of spinel between the oxygen partial pressures of 10-4.5 to 1 o- 6-5 atm. The analyzed compositions of liquids and solids are used to construct the phase diagram of ""Cu20"" -CaO-""F ez03"" system in equilibrium with metallic copper at fixed oxygen partial pressures."

Jan 1, 2007

By L. T. Pasiechnyk

After a brief review of the various hydrocarbon storage methods currently being utilized and statistics on underground hydrocarbon storage, this paper will briefly describe the technology involved in solution mining salt to create caverns of engineered shape and size and briefly discuss the economical and environmental advantages of hydrocarbon storage in solution-mined salt caverns. Other possible uses of salt caverns will be mentioned.

Jan 1, 1978

By Marketa D. Evans

The mining industry has a significant opportunity to capitalize on its past learnings in order to build better social relationships. The industry?s relationship with society is both critical and under pressure. Rising levels of public opposition and social conflict are already having material impacts on operations around the world. Industry has an opportunity to shape the future direction of this social engagement, build public trust and proactively respond to a material risk to operations, but first it needs to better understand the nature of the challenges and the urgency of addressing them.

Aug 1, 2013

By S. S. Teal, W. W. Weber

"AS THE TITLE implies, this paper will deal with the unusual rather than the standard practices as employed . at the property of North Rankin Nickel Mines, Limited. Fortunately •the mining, with the exception of permafrost conditions, and the milling practices, are the normal approaches dictated by the size, type, and character of the orebody. The unusual aspects are linked directly or indirectly to the isolated location and are •principally ancillary requirements or services covering a broad range from climate to supplies and from finance to entertainment. It is our intent to cover the more salient points of interest together with a brief description of the general operation.To understand the primary motivation of the mine, it must be made clear that North Rankin was conceived as a foothold in the Canadian North, that region embracing 40 per cent of the Dominion which ex-tends north of the commercial tree-line and which includes nearly 50 per cent of the Precambrian Shield, our mainstay of Canadian mining. Secondly, this project was born in an atmosphere of premium sales in the nickel markets, assuring a rapid pay-back of the heavy •capital expenditures. And finally, it has •been coddled through the stark reality of a competitive metal market with the hope and trust that the experiences and achievements will lead over the bill to a bigger and better mine in this virgin territory. This is the briefest story of the mine's history, but it pays tribute to the many people who, in thirty years since .discovery, have championed this project."

Jan 1, 1959

By R. J. A. Fricker

IT is the purpose of this essay to give a reasonably complete description of shaft sinking under a rock pentice in a small Northern Ontario gold property. Hallnor is in many ways an exceptional mine, but the sinking operations here described are but typical examples of the excellent practice for which Canadian mines and mining engineers are justly famous the world over. The worth of the subject lies, therefore, nor in its originality, but in its soundness; not in the spectacular, but in the economical and safe. Attention is particularly drawn to the excellent safety record and to the exceptionally low overall sinking cost. INTRODUCTION Prior to April, 1939, the Hallnor No. 1 shaft had been sunk vertically to a depth of 997 feet below the surface. It is a three-compartment shaft, 19 ft. 10 in. by 7ft. 7 in. outside the timbers (see Figure 1).

Jan 1, 1941

By T. Hofbauer, M. J. Dry, G. B. Harris, C. W. White

"Urban Mining is a term that is increasingly being used, and represents an appreciable source of secondary materials for the metals extraction industry, a source that does not incur mining costs, but does, at present, incur considerable disposal costs. Electric Arc Furnace Dust (EAFD) is probably the most common of these materials, with an estimated global production of 8 million tonnes annually, of which 1 million tonnes is generated in North America. The contained annual metal value in EAFD at current prices is of the order of $6 billion, yet, apart from the zinc, virtually none of this is recovered.Despite many attempts over the years, with pyrometallurgical, hydrometallurgical or hybrid processes, currently the only commercially viable method of treating these materials is smelting in a Waelz Kiln (or a Rotary Hearth Furnace), which essentially recovers only the zinc, in an impure oxide form, and generates a secondary slag waste, which is still toxic and requires disposal. This paper describes the development of a chloride-based treatment process to recover all components of the EAFD in a marketable form, which centres around the novel hydrochloric acid recovery and recycle operation. Laboratory, miniplant and pilot plant data are presented, leading to the definition of a viable process flowsheet enabling the recovery of pure iron and zinc products (the principal components of EAFD), together with secondary products such as copper, silver, lead, cadmium, magnesium and manganese. A rigorous mass-energy balance is used to examine the preliminary economics involved."

Jan 1, 2014

By Larry M. Southwick

There have recently been executives at major metals companies who have recommended that Greenfield Projects not be pursued. Greenfield includes not only new geographical locations, but also new technologies and new types of feed materials. In the middle part of the 20th Century, two such projects were successfully commercialized to recover nickel from Cuban lateritic ores. One project (at Nicaro) used the Caron ammonia-ammonium carbonate leach and the other (at Moa Bay) a high pressure acid leach. How both of these projects dealt with these Greenfield issues will be reviewed, based on the original reports that described the research and development of the plants. This study will include a review of the critical ore characterization and sorting issues, as well as the extractive metallurgical, product recovery and equipment selection and sizing problems and how they were solved at each stage of project development, from laboratory through one or more pilot scale plants to start up and operation. In one case, a major revision of the plant was made after several years of operation to correct operating, equipment selection and materials of construction problems that hindered economical operation. These descriptions will provide a guide through the complicated and critical issues that in recent times have caused many companies to give up on similar development. Even with the more advanced analytical and computational tools available to today’s mineralogists, engineers and metallurgists, the basic concepts with which these projects successfully addressed their sets of problems are still required. In addition, upper management, now perhaps further removed from hands-on experience than was common then, will see how complicated problems require intense and detailed effort to avoid failure in the field and capital blowouts. Build it and we will make it run, kicking the can down the road and borrowing operating and design concepts incorrectly on technological issues, or nine year olds on a sugar high making financial decisions are not philosophies by which to succeed with Greenfield Projects.

Jan 1, 2014

By A. G. Roach

Introduction The plant described in this paper is located at Coniston, Ontario, the smelting centre of the former Mond Nickel Company. Coniston is situated some eight miles east of Sudbury on the main line of the Canadian Pacific railway and on the Toronto-Capreol branch of the Canadian National-railways. The plant is now under control of the International Nickel Company, as a result of the merger of the two companies in 1929. The smelter proper includes four 50-in. by 240-in. blast furnaces and five 13 ft. by 30 ft. converters, and has a capacity of about 65,000 tons of ore charge per month. As accessories to the smelter there are a mill, where some 10,000 tons per month of low-grade ores are concentrated, and the sintering plant, which is the subject of this paper. The present 6-unit sintering plant replaces a former 4-unit installation. Here, fine ores, concentrates, and flue-dust are sintered on Dwight-Lloyd machines, the sinter produced being charged into the blast furnaces. At the time of writing (1931), only the concentrator is operating at capacity, due to present world conditions.

Jan 1, 1932

By K. Yamaguchi

To contribute highly efficient and environmentally conscious copper smelting process, several topics in chemistry of the continuous converting were discussed. Through the reviewing the authors' thermodynamic simulations, it is recognized that small amount and low copper content of the coexisting slag is preferable. Some discussions were added to the Takeda's diagram for Cu20-Fe0x-Ca0 ferrite slag, and the activity curves of the constituents were derived. Thermodynamic calculations were carried out on the copper contents of the slag during the blister copper formation. The dissolution of copper in slag decrease somewhat with increasing temperature, but the effects of increasing S02 pressure and decreasing %S in copper are considerable to increase in copper content of the slag. The optimum oxygen enrichment in the supplied air, and regulation of the oxidation degree for the blister copper are important in practice. The gypsum phase separation in the calcium ferrite slag was also evaluated thermodynamically, and concluded that decreasing temperature, increasing CaO content or S02 pressure, and extensive oxidation of the blister copper tend to separate CaS04. 0

Jan 1, 2007

By K. Yamaguchi

To contribute highly efficient and environmentally conscious copper smelting process, several topics in chemistry of the continuous converting were discussed. Through the reviewing the authors' thermodynamic simulations, it is recognized that small amount and low copper content of the coexisting slag is preferable. Some discussions were added to the Takeda's diagram for Cu20-FeOx-CaO ferrite slag, and the activity curves of the constituents were derived. Thermodynamic calculations were carried out on the copper contents of the slag during the blister copper formation. The dissolution of copper in slag decrease somewhat with increasing temperature, but the effects of increasing S02 pressure and decreasing %S in copper are considerable to increase in copper content of the slag. The optimum oxygen enrichment in the supplied air, and regulation of the oxidation degree for the blister copper are important in practice. The gypsum phase separation in the calcium ferrite slag was also evaluated thermodynamically, and concluded that decreasing temperature, increasing CaO content or S02 pressure, and extensive oxidation of the blister copper tend to separate CaS04.

Jan 1, 2007

By K. Turgeon, D. Larivière, L. Whitty-Léveillé, J. -F. Boulanger, C. Bazin

"The processing of ore containing rare earth elements leads to the production of an impure solution of these elements. The separation of the rare earths from the impurities and the production of individual elements is usually carried out by solvent extraction. The effectiveness of the extraction conditions and of the reagents is generally tested in the laboratory. This paper deals with the processing of results from solvent extraction laboratory tests planned to generate data redundancy. A method is proposed to take advantage of the data redundancy by accounting for the pH variation during the extraction. The parallel processing of several tests also allows estimating the equilibrium constants for the extraction. The proposed method produces equilibrium constants that are more reproducible than values estimated using conventional approaches. The method is illustrated with solvent extraction tests conducted on synthetic solutions of rare earth elements.INTRODUCTIONThe processing of ores containing rare earth elements (REE) usually includes the production of a concentrate of the minerals carrying the REE. These minerals, for instance monazite and bastnäsite, contain the 14 elements from La to Lu plus yttrium and scandium. As an example monazite has the general formula of (La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy…Lu)PO4 with a typical lanthanum content of 20-26%, cerium content of 40-50%, praseodymium of 4-6%, neodymium of 16 to 20%, and decreasing concentrations of heavier elements (Gupta & Krishnamurthy, 2005). During the processing of a REE mineral, it is generally not possible to isolate and separate a single REE from all the rest. The mineral molecules need to be broken (usually via a heat treatment followed by leaching with a base and/or an acid) to produce an aqueous solution of the REE of the ore. After purification of the solution, the REE can be precipitated as a bulk concentrate and sold to a refinery that separates the REE into particular groups of REE such as the light versus heavy REE or into individual elements such as lanthanum, neodymium, or europium oxides to yield value-added products."

Jan 1, 2016

By R. T. Erskine

"The No. 6 orebody is located 6 miles from the main op.eration of Brunswick Mining and Smelting Corporation Limited and includes open-pit and primary gyratory crushing facilities. Ore is transferred by truck to the secondary crushing facility at the main plant. About 3,500 tons of ore per day are crushed to minus % in. and ground to 68 per cent minus 400 mesh in rod and ball mills for flotation feed. Conditioning and aeration precede rougher flotation, and four stages of cleaning bring concentrates to a grade of 42 per cent Pb + Zn + Cu. Middling products are reground and refloated in a secondary flotation circuit, producing a cleaner feed and a final tails product. Primary bulk concentrate is treated with sulphur dioxide and steam-heated to l 70°F and the majority of the gangue is floated off, leaving a product that assays 57 per cent combined Pb + Zn + Cu and is suitable for marketing. This material is thickened, filtered, dried and loaded into railway cars for shipment to the smelter. Reagent use on flotation is conventional, with many compromises in dosage required to maintain the recovery of lead and zinc in the most advantageous proportions. Many refinements in the flowsheet have been made since start-up in 1966, and more may be made as laboratory and plant testwork indicate possible improvements."

Jan 1, 1971

AT the Annual General Meeting held in Winnipeg last March, the whole of one of the technical sessions was devoted to a special Symposium on Geological Investigations in Canada, introduced by a paper entitled The Geological Survey (lî which had been specially prepared by Dr. G. A. Young, Chief Geologist of the Survey, and had been published in the February BULLETIN, prior to the meeting. Geologists from each of the provinces contributed to the Symposium, including directing officials of the geological divisions of provincial Departments of Mines, representative geologists from the Universities, and company and consulting geologists. Space, unfortunately, does not permit publication of a complete record of the proceedings,_ or even inclusion of all contributions to the discussion. The following summary, however, gives what is believed to be a fair cross-section of the opinions expressed by representatives from each Province. The Symposium resolved itself largely into a discussion as to how the Geological Survey and the several provincial bureaus or divisions of geology could co-operate most effectively in the important task of carrying out geo-logical investigations, with avoidance of duplication of work and waste of effort, and, so far as broad principles are concerned, there was remarkably close agreement among those participating in the Symposium as to how the various types of investigation should be allocated as between the Federal and Provincial organizations. Briefly, the concensus was that the Geological Survey can render the most effective assistance by conducting reconnaissance investigations, with mapping at 4 miles to one inch, leaving to the provincial organizations the more detailed, and hence more local, studies and mapping at larger scales. There was general agreement that the preparation of base maps, essential to systematic geological investigation, is a service devolving upon the Federal Government.

Jan 1, 1940

By K. U. Kainer

Magnesium and its alloys as the lightest available construction metal offer a wide range of opportunities for the usage in transportation industries, especially Magnesium wrought alloys with their improved mechanical properties show a high potential for structural applications, While magnesium cast components have found their application the interest is now spreading to wrought alloys due to the possibility to get even more homogeneous and better properties compared to cast parts, Therefore alloy and process development especially for extruded and sheet material is a main concern to enhance the application of Magnesium wrought alloys, Castings are still form the majority of applications of magnesium alloys, although efforts to develop adequate wrought alloys have increased, In the presentation, the alloy requirements for processing of cast and wrought alloys will be discussed, The various processing routes and alloy compositions result in specific microstructures and properties which determine the potential use of these alloys, Today, the spectrum of available alloys covers standard alloys as well as alloys for use at elevated temperatures, The trend will be to further diversify the alloy compositions and to improve the alloy properties, Areas of concern still remain the wrought processing and the high temperature (creep) and corrosion properties of magnesium alloys, Examples of recent developments in these sectors will be given, The presentation will also provide an overview of the historical and current use of magnesium and an outlook on future applications.

Jan 1, 2006

By L. Bos

The availability and reliability of large grinding mills and their Gearless Mill Drives (GMDs) are of paramount importance for the grinding process. Although GMDs have been in service for decades, and are known for their operational efficiency (reliability and robustness with reduced operating cost per ton), compared to conventional drives, in the last decade due to certain reasons some failures led to serious unscheduled shutdowns and significant insurance events. The majority of these notable "insured" failures have happened on GMDs installed on relatively large mills, as the financial impact of a failure is proportional to the through-put of the mill. Despite the occurrences of these events, as mining operations are driven by lower ore grades and the ability to continue reducing operating costs per ton, the trend for having larger mills is still very present and there is no reason why this trend should not continue. It is obvious that if not handled correctly, the possibility of large value GMD loss events, coupled with the continuing increase in mill size or required availability and reliability targets, could potentially lead to major conflicts as it becomes difficult for the insurance companies to judge the risk and hence may result in hesitation to insure these grinding circuits. This paper will not only describe the conflicting situation from both an insurer's perspective and from an equipment supplier's perspective, but also how these conflicting challenges can be successfully mastered. It has to be noted that not only the mining companies themselves, but also their insurance companies and the involved equipment suppliers have a common interest: to reach the highest availability and reliability in order to avoid or at least minimize unscheduled shut down times, and most importantly prevent unplanned events that result in extended production stoppages or reductions in through-put of GMD driven mills. From the very beginning onwards, the complete service concept together with emergency plans must be integrated on every level in the design of the grinding circuit. This approach must be implemented continuously and without compromises by all involved parties during all following stages, such as basic design, detail design, manufacturing, quality inspection and testing, packing, transportation, storage, installation, commissioning, operation and maintenance. The concept of formal risk analysis related to mill operations, maintenance and spare parts strategies must be an integral part of mining companies? decisions related to the selection for installation and continued use of large mills powered by GMDs. The service concept in place for operating mills shall also have a clear focus on very early detection of any abnormalities, so that the risk can be mitigated and unscheduled shutdown times avoided. However, if a major failure occurs, then procedures and tools shall already be available in order to ensure that production impact is minimized.

Jan 1, 2012

By Randy McMeekin, Chris Twigge-Molecey, J. Peter Blake

The business objectives of a metallurgical project determine targets and constraints, such as the range of products, production capacities, in-service dates, and capital and operating cost parameters. Permitting is usually left to the project team, as are decisions regarding site location, technology, and construction approach. Success requires an orderly methodology, represented in this book by front end loading (FEL) phases: FEL1 examines several alternative approaches; FEL2 ranks and eliminates less economically or technically attractive options; and FEL3 develops the preferred option to the point of major permit completion, with defined scope, schedule, and cost to submit for approval to proceed with implementation in FEL4. Working through FEL1, FEL2, and FEL3, the project definition improves, estimates become more accurate, and project risks are reduced. The project design basis at the end of FEL3 is the control document for project implementation in FEL4.

Jan 1, 2015

By M. L. Connolly

Zinc production by Cominco Ltd. began in Trail in 1916 at a rate of 55 metric tonnes per day (t/d) and was increased ,in several increments until now electrowinning capacity approaches 750 t/d. The last increment, 40-t/d high-productivity electrowinning plant, was commissioned in 1974. In this paper, the design and operating experience with both the existing electrowinning plant and the new high-productivity plant are described.

Jan 1, 1977

By L. M. Southwick

"The history of extractive metallurgy is replete with examples of commercializing new processing technologies. The successes are widely reported, but failures seldom are. This is unfortunate, for usually we can learn more specifics on how to succeed in technology development by studying and thoroughly understanding their failures. Frequently one encounters a red herring that caused the whole effort to fail. A thorough and objective due diligence up front would have identified those red herrings and prevented the pursuit of a bad idea and the resulting destruction of capital. Due diligent analyzes performed before construction of three such bad ideas will be discussed. One is an EAF dust process, which pursued the red herrings of a poor understanding of the business, a naïve view of past experience, and false confidence in the technology. Another will examine the effort to commercialize a new pressure copper leach process that followed the red herrings of inadequate testing of the raw material, application of processing conditions that were inherently unsafe, and an improper assessment of the inherent advantages of past developments. The last is an alternative iron-making process, where the red herrings were incomplete and superficial assessment of prior pilot plant and demonstration plant tests, an assumption that the commercialization model of “build it and we will make it run” was viable, and a technology whose technical fatal flaws had already been identified. Unfortunately, capital destruction often also closes the window to more intelligent pursuit of technology development. TECHNOLOGY COMMERCIALIZATIONThe development and commercialization of new technology is a vital part of keeping industry profitable, able to deal with new sorts of feed stocks and current with economic, product, operational and environmental requirements. This is a difficult task in the best of times, and can be compounded when the developers become enamored of a particularly favorable characteristic of the project or of the product. These “red herrings” divert project focus away from the arduous path to success and, in the end, result in project failure."

Jan 1, 2012

By R. E. MacAfee

THERE have been great changes in the design, capacity, and pressure of steam generating units over the past fifty years. If we go back as far as 1890, the plants then existing were largely horizontal return tubular boilers, hand-fired, with the boilers supported on the brick sitting which was com-posed of red brick with, probably, a refractory lining one brick thick in the combustion chamber. About this time, the water tube boiler began to supplant the H.R.T. boiler and, where new plants were being constructed of any size, water tube boilers were largely installed. In those days, say from 1890 to 1905, a 250 h. p. water tube boiler was considered a large unit. These boilers were largely the straight tube type and were set with the first row of boiler tubes three to six feet above the grates. The brick setting was a combination of red brick and fire-brick. The fire-brick lining in the furnace proper was usually 9 in. thick and in the first pass 4 1/2 in., while the rest of the setting was entirely red brick. These units were largely hand-fired and were expected to produce about 100 per cent rating as a maximum. It may be well at this point to define rating, which is the evaporation of one boiler horse power per hour by each ten square feet of heating surface in the boiler. A boiler horse power is the evaporation of 34.5 pounds of steam from and at 212°F. Consequently, a boiler containing 2,000 square feet of heating surface is rated at 200 h. p. and the evaporation at 100 per cent rating is 200 X 34.5, which equals 6,900 pounds of steam per hour from and at 212°F.

Jan 1, 1939

By Janice Zinck, Maziar E. Sauber

"To counter the recent uncertainty in the rare earths market, diversify the supply source, and help meet the future demand in this sector Canada initiated development of several new rare earth deposits. In the past few years, a number of various studies on rare earths plant design have taken place mainly covering process development, process selection, and flowsheet design. The purpose of this paper is to provide an overview of known domestic and potential resources and reserves of rare earths and their status quo with a focus on the metallurgical processes using the information available in the public domain. Plant designs currently under consideration in Canada are reviewed and evaluated. An outline of the areas of opportunity for selective innovation and technology development in the rare earths flowsheet development and the associated risks and rewards is provided.INTRODUCTIONThe rare earth elements (REE) have a very small annual market, but they are categorized as very strategic metals vital to global economic growth due to their indispensability to the development of modern defence system, green technologies and electronic applications. The International Union of Applied and Pure Chemistry (IUPAC) defines the REE as the 15 elements on the lanthanide series on periodic table of elements, plus yttrium and scandium. REE are classified as light rare earth elements (LREE; La to Gd), and heavy rare earth elements (HREE; Tb to Lu). Physical properties and chemical reactivity of yttrium is similar to those of HREE, thus it is categorized as such. Properties of scandium are not similar enough to classify it as either a LREE or HREE (Weng et al., 2015; Sappin & Beaudoin, 2015). However, the mining industry does not always abide to this definitive classification of the split between LREE and HREE. Therefore, in a comparative study of projects, there is a need to pay attention to how the elements are classified."

Jan 1, 2016