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By J. M. Whiting

"North America has entered a period when greatly increased attention must be given to energy .supply and demand by government, industry and individuals. Such increasing concern about energy will be a long-term phenomenon, accompanied by continuing examination of future resource development and utilization. Those engaged in or associated with mining, a major energy consumer, are likely to experience a variety of problems which are associated with the end of an era of low-cost, virtually unlimited energy supply. Their efforts, furthermore, may be subjected to escalating public and government scrutiny, involvement and control. However, ever-growing recognition of the real and urgent necessity to systematically develop new energy supplies within Canada and the United States will provide unusual challenges and opportunities for those companies and individuals with mining expertise. The vast deposits of coal, tar sands and oil shale provide a relative certainty of supply which only stands to gain in attractive ness with time. In order to benefit from this aspect of certain supply, nevertheless, synthetic fuels will have to be produced at a tolerable cost. This will always require excellent process design and engineering. As synfuels development expands to any significant production level, however, and Jess than ideal reserves are scheduled, the usual geologic-productivity complexities encountered in making ore out of low-value rock will tend to become of prime concern. It is for this reason that the services of experienced mining personnel will be in growing demand in energy production."

Jan 1, 1973

By Webber. G. R.

Variation in content of some of the major and minor elements in the Lake Dufault granodiorite near Noranda, Quebec has been studied. The element variation and specific gravity data show a pattern consistent with the concept of a concentrically zoned intrusive on the western side of Lake Dufault with a potassium-rich core and a calcium-rich inner zone. The part of the intrusive on the eastern side of Lake Dufault is of more problematical origin, but the suggestion is made that it has resulted from assimilation of volcanic rock by the intrusive. THE purpose of this investigation was to test the application of x-ray fluorescence analysis to the study of variation in chemical com-position of the Lake Dufault granodiorite. The Lake Dufault granodiorite is an intrusive body approximately six miles long by three miles wide located four miles north of Noranda, Quebec. This intrusive is of particular interest because of its -

Jan 1, 1962

"Many underground mines are achieving extended life and optimizing existing facilities by mining at greater depths. The challenges to do this require a sound engineering approach to mine design and mine services, as well as ingenuity in safety design. The social consequence is full utilization of existing infrastructure.Accessing ores at depths of 2000 m to 3000 m requires exceptional hoisting design. May’s theme issue includes a paper that examines a case study of one such hoisting plant, with emphasis on the hoist rope selection at Agnico-Eagle’s Penna shaft. The paper also describes the process whereby consultation with provincial safety authorities resulted in a revised safety factor suited to the hoist. Another paper examines the challenges of ventilating mechanized mines to 3000 m, including air cooling and dilution of diesel exhaust emissions. Vent system designs are discussed, using sound engineering design, and proven technology that minimizes emissions to achieve cost efficiencies. The paper suggests design based on process and ventilation simulators to obtain realistic economic data at the design stage. Increased ground pressures present unique challenges for production and safety. While this is not confined to deep mining, one paper examines rock pressures and seismic events at the Brunswick mine, for which experience may be applied at depth. It describes seismic monitoring as a predictive tool in a real mine situation, and how it is used to improve overall recoveries and maintain worker safety."

Jan 1, 2004

By W. W. Cummings

The Mineral King Mine, owned and operated by Sheep Creek Mines is located in the Purcell mountain range of southeastern British Columbia. Production of lead and zinc concentrates commenced in 1954 some 60 years after the initial discovery. Low cost mining methods have been employed to extract 16,0C'O tons of ore monthly from large ore bodies formed by replacement in limestone. Extensive areas in the limestone are yet to be explored and success in the search for new ore bodies is anticipated.

Jan 1, 1960

By B. Wasmund, M. Y. Solar, I. Candy

The nickel laterite industry is divided into two camps when it comes to the grade of the ferronickels produced. One group, led by Falcondo and Cerro Matoso, markets high-grade ferronickels in the range of 35 to 40% nickel, while another group, led by SLN and the Japanese smelters, favour lower grades in the range of 20 to 25%. Because the ores processed by these smelters vary widely in terms of nickel content and iron to nickel ratios, it is probably more accurate to classify these smelters in terms of their iron recovery: Falcondo and Cerro Matoso smelt at lower reduction potentials and thus recover only 15 to 30% of the iron in their ores, while SLN and the Japanese smelters are very reducing and recover 45 to 65% of their iron. Low reductions generally imply higher slag losses and lower nickel recoveries, but also lower power and reductant requirements; higher reductions, the reverse. The question is, therefore, whether an economically optimum ferronickel grade exists for processing any given ore. This paper proposes a methodology for determining this optimum grade and concludes that nickel laterite smelters should favour low reductions and production of high-grade ferronickels.

Jan 1, 2008

By Dale C. H. Nevison

One of the most intensive of material rivalries is the confrontation between zinc die castings and plastic injection moldings. Pressed hard by the plastics industry, zinc die casters are learning how to make parts with less material yet without sacrificing quality. The key to this new trend is the technique of Thin Wall die casting. The obvious benefits of Thin Wall are lighter weight and lower cost. Again, obviously, these are the very selling points that put plastics into many appliance and automotive parts formerly made of zinc. One of the factors that has been most conducive to the outstanding growth of plastics has been the increasingly prevalent concept that "adequate" properties are sufficient, especially if there are cost advantages. Most of modern design today is oriented around the reasonable life of a product, rather than indefinitely extended life. This is simply an acknowledgment of the existence of a design environment that pervades many areas, reflecting the life-cyclic desire for change. Too often, so-called "weight-saving" materials end up being very costly - not only in production, but in durability and dependability. Change for the sake of change usually doesn't effect a change for the better. In the majority of cases, the best bet is to design in traditional materials and minimize the material needed, while maximizing the efficiency of the production process. Component prices of products to be produced from either plastics or zinc must be studied in detail to determine which material will produce the lowest cost of manufacture. It is not uncommon for two parts, similar in appearance at a casual look, to have a considerable difference in energy requirements and production costs. Detailed cost estimates of the advantages of each material should therefore be prepared for zinc and plastic parts before the final design and material selection decisions are made.

Jan 1, 1978

By G. E. Murray

Introduction The development of the method for recovering zinc from lead blast-furnace slags at Trail is interesting and important in the history of both lead and zinc metallurgy. Many efforts have been made in the past, particularly in Germany, to make economic recovery of zinc from slag. The Pape process on Oker slags was successful and is being worked at the present time. More recently the Waelz process has come to the fore. One effort at Cockle Creek, Australia is of special interest in view of subsequent developments. This was re-ported in detail by Guy Courtney in 1920(1). It deserves mention as it shows how, as in many other instances in the metallurgy of lead and zinc, important pioneering work has been done in Australia. These experiments, started over 25 years ago, comprised reduction with coke, powdered coal, and eletrothermically in carbon-lined furnaces. The so-called slag eye furnace, which volatilised the metals from a blast furnace running with a hot top, was also investigated.

Jan 1, 1933

By Alan E. Gallie

One of the requirements for the successful waging of war is an unlimited supply of iron ore. In the spring of 1941 the demand for iron ore was expected to exceed the supply. This was particularly so in the case of high-grade lump iron ore, essential to the open-hearth process of making steel. The bulk of Canada's iron ore was imported from the United States. At this time, Canada was making every effort to conserve United States funds for more vital purchases. For these reasons, the development of Canadian iron ore resources became of prime importance. Several companies undertook investigations and one of these examined the old Josephine deposit. Location The Josephine property is in the district of Algoma, in the Michipicoten area of the Sault Ste. Marie mining division of Ontario. It is 120 miles north of Sault Ste. Marie and 20 rail-miles east of Michipicoten harbour, on lake Superior (see Figure 1). Transportation in the area is furnished by the Algoma Central and Hudson Bay railway. The Michipicoten branch of this line passes within a mile of the Josephine mine. Michipicoten harbour provides a port through which iron ore is currently shipped. Power in the area is supplied by the Great Lakes Power Company, with generating plants on Michipicoten river, on Montreal river, and on St. Mary's river at Sault Ste. Marie. A series of transmission lines cover the district and one of these is connected to the Josephine mine by a 3 ½-mile branch line. History The Josephine property was staked by Alois Goetz in 1899. Before the claims could be recorded, the township in which they are located was given to the Algoma Central & Hudson Bay railway as part of a land grant. As a result, the ownership remained in dispute until August 24th, 1906, when a settlement was arbitrated by the Honourable Frank Cochrane. His ruling is interesting and is quoted in part.

Jan 1, 1947

By S. Noh, T. K. Kim, B. O. Lee

Future nuclear reactor systems such as a sodium-cooled fast reactor are being designed under severe conditions in terms of operating temperature and irradiation fluence compared to current commercial reactors. For realization of such systems, it is necessary to develop an advanced structural material having both high strength and irradiation resistance at high temperatures. Oxide dispersion strengthened (ODS) steel is considered as one of the most promising structural material because of its excellent creep and irradiation resistance on the basis of uniformly distributed nano-oxide particles with a high density. Up to now, ODS steels have been intensively studied and developed to apply these materials to the in-core structural component of future nuclear systems. Several advanced ODS steels were designed and fabricated by a mechanical alloying, hot isostatic pressing and hot extrusion processes. This study focuses on the effects of heat treatment parameters during the fabrication process parameters on the microstructures of ODS steels for future nuclear system applications.

Jan 1, 2015

By Knud Sinding

Environmental reporting by mining firms takes many forms and change frequently. The objective of these reports is related to increasing the legitimacy of mining firms with their diverse stakeholders. This study, focusing on internet-based reports, shows that there are considerable variations in reporting. This phenomenon is interesting because it belies the efforts pursued by leading industry members under iniatives such as the Global Mining Initiative and the Mining, Minerals and Sustainable Development project. The observed variation, both internally among reports and between reports and other industry policy statements, suggests that the industry needs to explore the possibilities for more convergence in terms of reporting quality. Based on theoretical constructs from the management literature we present a series of arguments defining necessary and sufficient conditions for durable and well-institutionalized reporting practices and standards.

May 1, 2002

By P. O. Sandstrom

"Atlas Copco is introducing a new patented method for full-face boring. This paper presents the basic principles of the boring action and discusses the present experience regarding performance and costs. The Atlas Copco ""Full-facers"" are designed for hard-rock applications, although they are successfully boring in soft ground without major changes. The unique patented boring principle referred to as the 'Undercutting Method' permits these machines to bore, economically, in harder ground than machines based on the 'crushing principle'. This is mainly due to considerably lower cutting-tool costs, as the tungsten carbide tips only are in contact with one-third of the bored volume. The remaining rock is 'undercut' and peels off from a slight back pressure.The undercutting method also permits boring of non-circular headings and Atlas Copco has already manufactured two machines for rectangular drifts. This concept could revolutionize development work in mines employing trackless equipment."

Jan 1, 1971

By P. L. Richard

An open pit a mine can be thought of as a business unit, with capital, operating and maintenance costs that exceed those of many large business enterprises. Truck-and-shovel operations have an inherent ?looseness? to them, unlike manufacturing or processing operations where production components are tightly coupled (through conveyors, material flow in pipes, assembly lines, and so on). Effective monitoring and control of truck-and-shovel operations requires a combination of both information systems and performance management. Production monitoring systems can impact operations at three levels: minute-by-minute decisions during the shift, procedures, and policies. The technology of production monitoring ranges from real-time data collection to manual entry of time card data into a computer. Time card information is too coarse to effectively manage a multi-million dollar fleet of mobile equipment, so a higher level of production monitoring is required. People issues affect whether the implementation will be a success or a disappointment. Considerations that affect the people issues are discussed, including common obstacles, and key success factors. A balanced scorecard approach must be used, since uni-dimensional measures of performance like tons produced give no indication of whether the production was achieved at the expense of another factor.

May 1, 2004

By P. L. Richard

An open pit a mine can be thought of as a business unit, with capital, operating and maintenance costs that exceed those of many large business enterprises. Truck-and-shovel operations have an inherent “looseness” to them, unlike manufacturing or processing operations where production components are tightly coupled (through conveyors, material flow in pipes, assembly lines, and so on). Effective monitoring and control of truck-and-shovel operations requires a combination of both information systems and performance management. Production monitoring systems can impact operations at three levels: minute-byminute decisions during the shift, procedures, and policies. The technology of production monitoring ranges from real-time data collection to manual entry of time card data into a computer. Time card information is too coarse to effectively manage a multi-million dollar fleet of mobile equipment, so a higher level of production monitoring is required. People issues affect whether the implementation will be a success or a disappointment. Considerations that affect the people issues are discussed, including common obstacles, and key success factors. A balanced scorecard approach must be used, since uni-dimensional measures of performance like tons produced give no indication of whether the production was achieved at the expense of another factor.

Jan 1, 2004

By Peter A. Adcock, Rob Fraser

Interest in monitoring nucleation overpotential in electrometallurgical processes dates back some 40 years or more. Conversely, remarkable progress has been made in recent years on describing in detail the processes involved in the formation of thin films by electrodeposition. The newer body of work underscores a need for greater clarity in speaking about the role of nucleation and in the acquisition and interpretation of nucleation overpotential measurements – the aim of this paper. In electrometallurgy, it is generally desirable to form deposits that remain smooth, compact, and relatively fine-grained while the deposit grows to a thickness on the order of 5-10 mm, about 100 times thicker than technological thin films. Hence, we distinguish two kinds of nucleation that can result in formation of new grains:- (1) initial nucleation (onto the substrate surface) of islands that coalesce into growing deposit, and (2) ongoing nucleation of new grains on the deposit surface long after the substrate has been covered and ceases to have a direct influence. Nucleation overpotential of the first type should be measured on an electrode surface truly representative of a real industrial substrate. The second type requires judicious choice of electrode material – an “ideal foreign substrate”. In general neither the industrial substrate nor native metal to be deposited is suitable for measurement of the second type of nucleation overpotential, because of interference by other processes. For the future, clear terminology is needed to distinguish these two types of nucleation potential. The second is the one for which the type of plot dubbed by Moats and Derrick as an “Adcock plot” and by us as a “Kerby-Adcock plot” was first conceived and correlated with relatively thick zinc electrodeposits. The data of Moats and Derrick showing trends for copper electrodeposition on stainless steel and on copper electrodes are interpreted within this framework.

Jan 1, 2016

By Glen A. White

The level of impact and mitigating measures that are forecast in an environmental assessment (EA) for a new, or significantly modified, metallurgical processing facility or mine are taking on increasing importance during the subsequent life of the facility. The basic premise is that one is authorized to operate within the envelope defined by the approved EA. Operations inevitably change as they develop and mature, and at some point, one is faced with the prospect of re-doing the original EA work. This can lead to significant development delays. Cameco Corporation (Cameco) has played a major role in developing the northern Saskatchewan uranium mining industry over the past decade. Through the EA process, the company has developed ideas on what works well in generating approvals that give the operator some future flexibility. Early introduction of concepts for potentially different mining and processing methods, as well as contingency plans if things do not work out exactly as predicted in the original EA, can make subsequent regulatory approval for change a more efficient process. One must also preserve the principles of open consultation upon which the EA process was originally based. As such, involvement and support from local communities and other stakeholders is required to ensure the long-term success of the EA process.

May 1, 2004

By John R. Goode

"This paper reviews options for the separation of a mixture of rare earth elements (REE) into its component elements. Earlier separations used selective chemistry such as double salt precipitation and reductive/oxidative processes – methods that still have a place in the industry. Fractional crystallization was developed for more complete separations of adjacent REE. The latter method was replaced by ion exchange (IX), which was in turn replaced by solvent extraction (SX). Two main SX chemistries are in use, solvation and cation exchangers, with several variants (mixed solvents, ionic liquids, etc.) now under investigation. SX plant configurations have evolved including advanced techniques like “hyperlinking”, novel saponification methods, and alternative stripping techniques. The classic mixer-settler is the most commonly employed device although centrifugal contactors have been pilot-tested. Non-dispersive SX options including microfluidic devices and membrane-assisted SX techniques are being developed and could revolutionize the SX option. Other REE separation techniques now being studied include Molecular Recognition Technology (MRT), Free Flow Electrophoresis (FFE), newer IX systems, and electrolytic processes. Additionally, the classical crystallization and selective precipitation methods and newer bacteria-mediated processes, chloride volatilization, high performance liquid chromatography, and magnetic separation systems have been studied. This paper reviews the options and concludes that conventional SX is the technology of choice but viable alternatives could be demonstrated and acceptable within a couple of years.INTRODUCTIONThe chemical properties of the individual REE are very similar which is why REE minerals and ore deposits almost invariably contain a mixture of all fifteen REE, i.e., La to Lu plus Y. That said, the distribution of REE in a given deposit is frequently dominated by the light REE (LREE, i.e., La to Nd). Examples include the Bayan Obo, Mianning, Lynas Mt. Weld, and Molycorp Mountain Pass deposits where heavy REE (HREE – Sm to Lu and Y) typically account for well under 5% of the REE content. The LREE operations produce some HREE but the main sources of these important elements are the ionic clay deposits of Southern China. Importantly, all of the REE recovery operations referenced above, except for cerianite-bearing ionic clay deposits, initially produce a mixed REE precipitate or calcine with a REE distribution similar to that in the ore (Goode, 2016). However, the consumers of the REE, the manufacturers of magnets, phosphors, catalysts, optical glass, etc., require separated products with purities generally ranging from 99% to as high as 99.9999% depending on the element in question and the end use. Hence there is a need to separate the individual REE one from the other. This paper is intended to review the options."

Jan 1, 2016

The negative effects of pyrite and pyrrhotite on thiosulfate gold leaching have been investigated. Possible remedies to reduce some problems are discussed. In a gold bearing pure silicate ore, 92% of gold could be extracted within 3 hours using a solution containing 0.2 mol/L ammonium thiosulfate, 0.9 mol/L ammonia, 30 - 300 ppm copper sulfate and 8.6 ppm dissolved oxygen at pH 10.26. The thiosulfate consumption was 7.1 kg/t under these conditions and could be further reduced to 3.5 kg/t by decreasing the dissolved oxygen to 0.3 ppm. Addition of 16% pyrrhotite or pyrite into the silicate slurry led to a decrease in gold extraction by 2% or 9% respectively and an increase of thiosulfate consumption by 11 kg/t or12.8 kg/t respectively in three hours. Several adjustments, such as increasing copper ion and ammonia concentration and reducing the dissolved oxygen level to 0.3 ppm resulted in increased gold extraction and lower thiosulfate consumption despite the presence of these sulfides.

Jan 1, 2005

By Linda Hodgson

1. Introduction ?Northgate Minerals Corporation is a mid-tier gold and copper producer with mining operations, development projects and exploration properties in Canada and Australia. ?Kemess Mine is Northgate?s principal operation. Where in the world is Kemess? ?Kemess is located in north-central British Columbia,430 kilometres northwest of Prince George. ?The Kemess South complex consists of an open-pit mine, a 52,000 tonnes per day mill and various ancillary support facilities including maintenance shops and housing for Kemess' 340 full-time employees.

May 1, 2010

By Kevin J. Palmer

The introduction of the National Instrument (?NI?) 43-101 Standards of Disclosure for Mineral Projects has led to some very specific requirements to reporting a Mineral Resource estimate for mineral projects to the public. There are elements of the Mineral Resource estimate that are based on the qualified person (?QP?) completing the work to accepted industry practices and applying their relevant experience. There is no document that defines what is considered the accepted industry practices. There are guidelines provided by the Canadian Institute of Mining, Metallurgy and Petroleum (?CIM?) but, in general, the industry practices are dynamic and often different QPs will estimate the same mineral project in different ways. This sometime happens on exploration projects as they proceed from one study to the next. The focus of this paper is to provide a review of some of the current practices that are published in Technical Reports (Preliminary Assessment to Feasibility studies) with respect to classifying a Mineral Resource as Inferred, Indicated and Measured and the grade interpolation and modeling methods, data support (i.e. geological drill hole spacing) and validation methods employed.

Oct 1, 2010

By Ian McC. Stewart

"Seam gas flow in coal mines takes place through a medium which has both capacity and resistance and can therefore be expressed in terms of the basic diffusion equation, provided that the characteristics of the system can be adequately described. It may be possible to lump the variations from point to point in a seam together as an effective diffusivity. The paper discusses the characteristic flow-time patterns for various types of openings and the particular features of coal and seam which influence the diffusivity.Two field experiments are described in which gas make to a heading and to a borehole were measured in a mine for which considerable data on coal sorption properties were available. Incremental gas flow measured from the borehole experiment predicted the actual flow from the heading measurements remarkably well. The effective permeability adjacent to the face was much higher than expected from the properties of the coal. The incremental flow measurements to a horizontal (in-seam) borehole showed a striking picture of advancing 'relaxation' behind the face which is not discernible by other experimental means."

Jan 1, 1971