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By R. C. Reed, L. T. Wu, H. C. Harada, K. Kawagish, R. T. Wu

Oxidation of pure metals is a chemical reaction in which the metal loses one or more electrons, such that the atom of the metal changes from the neutral state to a positively charge ion and reacts with oxygen to form an oxide of the metal. The oxide can form as a protective and adherent scale that slows down further oxidation, or may spall off repeatedly, exposing fresh metal surface to react with oxygen. In multi-component alloy systems such as typical high temperature NiCrAlY bond coats, more than one oxidation mechanism may take place at once and thus, complicates the study of oxidation. To better understand the competition between formations of oxides of different compositions, a thermodynamic assessment is carried out to study the oxidation mechanism of a Ni-27Cr-9Al (at %) ternary alloy. Based on the assessment, it is demonstrated that the layering of different oxides can be determined, with the most stable oxide (alumina) existing directly above the metal-oxide interface and the least stable oxide (nickel oxide) locating on the outer most layer. A comparison between the calculated results and previously published experimental observations shows excellent agreement.

Jan 1, 2010

By D. D. Downing

This paper is a review of material selection considerations concerning protective coatings in the mining industry. The discussion will cover both capital-dollar projects and maintenance requirements. Emphasis will be on industrial finishes for structural steel and process equipment subjected to aggressive atmospheres. The presentation will cover the total needs of a job, emphasizing not only the owner's requirement for a cost-effective system during plant operations, but also taking into consideration the short-term requirements of general contractors, steel fabricators, erection firms and paint contractors.

Jan 1, 1979

By T. C. Holmes

"Dome mine, in the Porcupine mining camp of northern Ontario, is one of the important gold mines of Canada, its production of gold from the commencement in 1910 to the end of 1946 having a value of $149,000,000.GENERAL GEOLOGYThe oldest rocks in the mine are greenstones of Keewatin age(l). Those to the south are known as the southern greenstones, but little is known of their structure. Those in the northwest part of Fig. 1 and the north part of Fig. 2 are known as the northern greenstones or greenstone 'nose'. They face north, dip steeply north, and end to the east against an unconformity which pitches northeast about 20°. The volcanics are overlain unconformably by Timiskaming .conglomerate and slate. All these rocks are cut by porphyry. Closely associated with the porphyry is a group of rocks that have suffered extreme alteration. Diabase dykes intrude all the other rocks and the ore. The principal massive rocks in the mine are two adjacent flows known asthe andesite (south) and dacite (Fig. 1). They are composed chiefly ofmassive, medium-grained lava. Pillows, flow lines, and other typically volcanicfeatures are found along the tops of both flows and at other places in theandesite. These parts nearly everywhere show a slight schistosity panllelwith the flows except in the orebodies, where they are massive."

Jan 1, 1954

By H. Kuboyama

The synergistic effects of polymer additives such as gelatin and polyethylene glycol) (PEG) and Cl- on Cu electrodeposition have been investigated by measuring the polarization curves for Cu deposition, by rotating ring-disk electrode technique and by AC impedance measurements. The cathode potential for Cu deposition was greatly polarized in solutions containing both Cl- and gelatin or PEG, showing evident synergistic effect of polymer additives and Cl- on Cu deposition. The cathode potential was shifted to the less noble direction with increasing the concentration of Cl- in solutions containing polymer additives and showed the maximum polarization at Cl- concentration range between 0.1 and 1 mmol/L. The rotating ring-disk electrode technique revealed that Cu deposition in solutions containing small amounts of Cl- proceeded with initial formation of adsorbed intermediate CuClad. The Cole-Cole plots obtained by AC impedance techniques suggest that the reduction of CuClad is suppressed by polymer additives. The morphology of Cu deposited from solutions containing both PEG and Cl- showed the compacted surface composed of smaller grains due to an increase in the overpotential for Cu deposition.

Jan 1, 2007

By B. A. Monkman

"IntroductionONE OF :THE most effective methods by which the construction industry is combatting mounting building costs is by making increased use of lightweight materials, thus reducing the dead load to be carried •by structures. This applies to non-metallic materials as well as to metallic ones, and particular attention has been given to developing lightweight aggregates for use in concrete.The use of lightweight aggregates is not new and, in fact, dates back to the Roman Empire, when pumice was used in the walls and domes of the Roman buildings. More recently, and up to a decade or so ago, the demand for these aggregates was met from deposits of volcanic cinders, pumice, scoria, etc., and from the by-products of blast furnaces and coal burning boilers. However, these sources of supply are no longer sufficient to meet the demand, for transportation costs pretty well restrict the use of the natural lightweight aggregates to the western cordillera regions where the deposits of these materials occur, and the use of expanded slag aggregates to the areas neighbouring the plants where slags are produced. As for cinders, the supply has been greatly reduced by the conversion of industry to fuel oil, natural gas, and powdered coal, and the large stockpiles which existed previously have been pretty well exhausted.Industry's approach to the problem of a decreasing supply, in the face of an increasing demand, has been characteristically direct. The solution has been to construct plants whose sole .purpose is to produce economically an acceptable light-weight aggregate from materials close at hand."

Jan 1, 1955

By Terry A. Lee

The grade of mineral resource estimates underpin all major economic considerations of mining prospects. While there are reporting requirements to satisfy when stating a mineral resource estimate, an examination of NI 43-101 style reports suggests that authors believe that there are a number of ways of addressing these requirements. As a reader of these reports, some processes are helpful and others are not so in getting a real appreciation of how realistic is the mineral resource estimate. Critical to the quality of the mineral resource estimate is how realistic is the economic mineral concentration component. In many cases, this parameter is called grade. The industry experiences increased difficulty in achieving realistic grade estimates as the sample grade variability increases. The level of transparency in a mineral resource estimate is very much a function of the competence of the author. An objective presentation of the critical data, such as grade sampling variability can assist a reader in determining if the geology of the mineral concentration is adequately understood and how realistic is mineral resource grade estimate. This paper has considered 75 NI 43-101 style reports released in the past 2 years. The review demonstrates features that were helpful in determining how realistic the mineral resource grade estimate is. If there is insufficient transparency in a report, there is a high probability that the mineral resource grade estimate will not be realistic.

Apr 1, 2005

By C. Holmes, T. Holmes

Engineered-in material handling problems are responsible for significant unrealized value in mineral processing plants. At the root, is a lack of awareness and understanding of bulk material handling science and how important it is, especially in early design stages. Mineral processes add value to mined raw feedstock through physical and chemical transformations in unit operations, but only if the material can flow through them. Essentially, each unit operation receives a unique feedstock and produces a unique product to be collected, transported, and fed into the next unit operation. Such material-handling systems can only be expected to achieve design throughput if the system equipment is designed to the materials’ characteristics, over their full range of conditions. This requires quantification of flow properties to support the necessary customized equipment designs. Too often, assumptions or “library values” of a material’s properties are used as the basis for flow modelling and conceptual, and sometimes even detailed, design. This is especially true for hazardous materials like uranium ore, for which the additional precautions, costs, and time necessary for safe handling are often used to rationalize postponing or even bypassing testing. The surprises that often transpire in the wake of insufficient material handling consideration can have acute and costly effects. Fortunately, there is a better way.

Jan 1, 2020

Cansolv® S02 Scrubbing Technology was described in a paper in Copper/Cobre 03. Four years on, the technology is operating at a full scale production facility.Hindustan Zinc Limited expanded their capacity by installing the AUSMELT process. The process proceeds through smelting, slag reduction, slag cleaning and holding stages sequentially in the same vessel, resulting in widely varying off gas characteristics. The off gas is suitable for treatment is a conventional acid plant for a modest proportion of the day, but at other times produces off gas too high in S02 to be discharged to atmosphere. Cansolv® S02 Scrubbing Technology was identified as a means of effectively removing the S02 down to low levels from the off gas during all stages of the pyrometallurgical process. Furthermore, the Cansolv® S02 Scrubbing System Technology produces high purity S02 that allowed for the captured S02 to be directed to an existing acid plant, avoiding the capital cost of new acid making capacity.

Jan 1, 2007

By Matthew R. Ward

This paper aims to describe the reasons and methods to extend enterprise networks into underground mines. Currently mines use a number of communication networks for telephones, PLCs, two-way VHF radio and computer networking. Each system can have different wiring, protocols, converters and interfaces all which require expansion and maintenance. The convergence of voice, video and data using Ethernet and TCP/IP has the very real benefit of one ?wire? for underground networks. Now that the majority of underground equipment can communicate using TCP/IP, network convergence can offer reduced network expansion and maintenance costs. Cost savings are good, but the truly exciting aspect of network convergence using Ethernet is the low-cost, high speed wireless networking now available . These wireless networks offer an opportunity to facilitate mining automation even on a small budget. How would mine operators change they way they operate if they could gather vehicle location and data in real time? What about controlling equipment remotely? The list of applications is long and includes traffic control, dispatching, real-time ore blending, tele-operation, automated production reporting, vehicle health monitoring, elimination of paper forms and immediate network access for surveyors and geologists. An ideal converged network for underground mining would be robust, inexpensive, easy to expand, enable fast and secure connections while keeping voice communication performance equivalent or better than what is now provided by VHF radio

Apr 1, 2005

By Melvin S. Taylor

The environmental control program at Cassiar Mine is an active one involving government, unions and company personnel all working together to achieve a goal- "A clean and safe working environment". This can only be achieved by utilizing three of Cassiar's most important resources; i.e., people, time and money. Past environmental programs have more than proved that the goal can be reached and. with the future programs now in progress. Cassiar Asbestos will achieve its environmental goals.

Jan 1, 1978

By A. Zarei-Hanzaki, S. M. Fatemi-Varzaneh, M. Haghshenas

The microstructure in modified semi-solid ALTHIX (A356) alloy consists of aAl phase with Al/Si eutectic structure. Silicon phase in eutectic structure is coral like with fine fibers. The lack of good ductility in this alloy is related to the presence of silicon fibers. Accordingly many investigations have been recently conducted to modify the Si morphology through Thermomechanical processing on this alloy. In the present work an ALTHIX (A356) alloy was deformed at 450°C, 500°C and 540°C through different strain rates. Consequently the silicon fibers were broken into small particles. The results indicated that the Si particles may coarsen according to Ostwald ripening mechanism at 540°C deformed by rate of0.0005 sec-1 & 0.0001 sec-1-

Jan 1, 2006

By Peter N. Blakey, Jean-Paul Paquette, Barton A. Thomson

"FROM THE BEGINNING OF THE PIT, it was known that the surface mining method had a projected life of about ten years, and that the ore extended to depths recoverable only by underground mining. When serious consideration was given to underground mining in 1968, it was realized that tremendous advantages could be gained by starting the underground mine as early as• poss1ble. These included: 1. The availability of underground ore for grade control, which would become more difficult as the pit deepened. 2. The need to develop new systems, equipment and skills to take full advantage of the technological revolution in underground mining. 3. Early knowledge of rock behaviour through trial mining on a small scale prior to finalizing plans for major blocks. In addition, the pit would be available to guarantee the mill supply if problems were encountered. 4. With sufficient time and early mining experience a much better job could be done on all mine planning. Because ample reserves of economic underground ore were virtually assured, the desired underground mining capability became a function of two restraints: first, the time required to excavate and construct the permanent headframe, shaft and ore-handling facilities necessary to handle large volumes of stope ore; second, the time for lateral and stope development on at least one level which would normally follow shaft sinking. The decision made was to move immediately on the permanent hoisting installations and at the same time embark on the planned ramp from surface, which would allow much stope preparation to be completed prior to .bringing the shaft on stream. Both projects were placed on an urgent basis early in 196S' and the following decisions made shortly thereafter."

Jan 1, 1974

By J M. Anderson

The cable belt conveyor installation at Craigmont Mines Limited, Merritt, B.C., has the greatest one-stage vertical fall of any conveyor installed overland in Canada. Since the late summer of 1961, this conveyor has carried more than 5,000,000 tons of copper ore from open pit to concentrator site. When the conveyor is loaded, the drive motor acts as an induction generator, delivering power to an external circuit. This paper covers the selection, the operation, the performance statistics, and the installation and operating costs of this conveyor system. Introduction T HE Craigmont mine is located in the south-western interior region of the Province of British Columbia, approximately 240 miles northeast of Vancouver. A moderate climate, good roads, service by the Canadian Pacific Railroad, power from the British Columbia Hydro Authority, gas from the nearby main line of the Inland Natural Gas Company and close proximity to the village of Merritt provide a favourable location for this mining operation. The ore occurrences at Craigmont have a vertical extent of 1,500 feet,

Jan 1, 1965

By Soumitry J. Ray

Poor visibility of powered industrial vehicles, such as forklifts, used in industry is often the cause of accidents that include pedestrians. Current standards allow up to 20 % non-visible regions for forklifts where measurement of these regions is performed by using lamps. A collaboration of research organizations, including National Institute of Standards and Technology, Georgia Institute of Technology (NIST), and Direct Dimensions, has been evaluating advanced methods for measuring a forklift operator?s visibility. These methods can potentially improve visibility standards. They can also help forklift and sensor manufacturers to determine (1) how visibility-assist sensors and algorithms can be designed and (2) where sensors can be mounted on forklifts. This paper includes explanation of visibility measurement experiments performed and results, associated language suggested to standards organizations, and a prototype design for measuring the visibility of forklifts automatically.

Aug 1, 2013

By J. Awmack, M. A. Tomlinson, P. J. Lind

"Peñasquito is a complex polymetallic deposit containing gold, silver, lead, zinc, and copper and is one of the largest producers of gold in Mexico. Mining activity is currently transitioning to a second open pit, Chile Colorado, which will be mined concurrently with the existing open pit, Peñasco. The ore bodies are located within diatreme pipes and into the surrounding sediment formation. In the coming years, mining will be carried out in more sedimentary zones, which are significantly higher in organic carbon content. Organic carbon in the feed influences both flotation and leaching operations. Several changes are being implemented to the Peñasquito flowsheet to mitigate the effects of increased organic carbon in the plant feed. These include the use of alternate reagent schemes, construction of a carbon pre-flotation circuit, implementation of a pre-leach flotation circuit ahead of pyrite leach, and evaluation of a tertiary process for separation of carbon and precious metal minerals.INTRODUCTION Goldcorp’s Peñasquito operation is located in the Mexican state of Zacatecas, approximately 200 km from the city of Zacatecas in the Mazapil municipality (Figure 1). Peñasquito has been in operation since 2009, with mining carried out by open-pit methods. Oxide ore has been processed in a heap leach facility and sulfide ore is treated in the sulfide processing plant. The processing capacity of the sulfide plant is 130,000 tonnes of ore per day and in 2016 production amounted to 465,000 ounces of gold, 17.6 million ounces of silver, 109 million lb of contained lead in lead concentrate, and 263 million lb of contained zinc in zinc concentrate (Goldcorp Inc., 2017). To recover more of the contained gold and silver and to mitigate the impact of increasing organic carbon content in the ore, a number of significant changes are being made to the operation."

Jan 1, 2018

By D. J. McLaren

"Arctic Canada is one of the largest undeveloped terrains remaining in the world, and is in many ways unique. The ecological balance of the region is more delicate than tropical or temperate regions of similar size. This region is likely to be developed by research for and production of resources, primarily petroleum, in the immediate future. As well as sensitive terrain surface caused by permafrost in some areas, many large and small mammals and birds are also in a delicate balance with the environment. Small changes in this balance can have large effects.The probability of finding petroleum in different regions varies widely, but already there are good indications on the mainland and in the Islands that both oil and gas are present. Geophysical work in the offshore, particularly the Beaufort Sea, suggests further promising potential. Possible reserves in the Islands and mainland Arctic may amount to 50 or more billion barrels.A responsible approach to problems facing exploitation in an Arctic environment includes the careful monitoring by industry of likely effects of their activities. The Mackenzie Valley Pipeline Research Association test loop at Inuvik provides an example of such monitoring. Outside Canada, the operations at Prudhoe Bay on the north coast of Alaska show how major companies may operate responsibly and reduce environmental interference to a minim'.::at. Nevertheless, four variables must affect any decisions to be made concerning energy resource exploitation in the Arctic. These are man's need for energy, economic and industrial pressures to develop energy sources, the desire to preserve a deteriorating environment, and the role of government as representing all individuals in the country and their several points of view. Factors that must be taken into account in making any decisions include the importance of Canadian oil in a world picture, the need for alternative sources of energy in the near future, the depletion of nonrenewable resources at an accelerating rate and the increasing awareness that the major problems facing man have no direct technical solution and that social or political decisions must precede further techno-logical development."

Jan 1, 1971

By P. Z. Caverhill

In this section of the province only the most meagre of surveys have been made and because these are not sufficient to determine with any degree of accuracy even the total forest area, the information presented in this paper is not complete. Area: -The area south of the Canadian National, and served by the Pacific Great Eastern, is roughly 38,000. square miles, 30,000 of which is classed as productive. This is approximately equal to the productive area of Norway, or half of Finland-or of 30 per cent of Sweden. It is larger than that of either Nova Scotia or New Brunswick. Eliminating from the productive area 3600 square miles of grass-land and areas capable of agricultural development, 26,000 square miles (16,600,000 acres) remains as absolute forest-land, as compared with the 55,000,000 acres of Sweden, the 37,500,000 acres of Finland, the 17,000,000 acres of Norway, and the 7,600,000 acres of Austria.

Jan 1, 1925

By James R. Yeager, Eric L. Hoffman, John R. Clark

"Abstract -This paper describes fire assaying and ‘high tech’ alternatives for gold analysis, including advantages and disadvantages of each method. These ‘high tech’ methods include INAA (instrumental neutron activation), aqua regia digestion/AA (atomic absorption), GFAA (graphite furnaceatomic absorption) or ICP/MS (inductively coupled plasma emission mass spectrometry) and a combination of cyanidation with AA, GFAA or ICP/MS methods.Fire assay remains the stalwart among analytical methods for gold but, even with its multiple analytical finishes, is not fool-proof for recovering 100% of the gold present. Consumers of assays should not blindly trust the assay results without consideration of quality control data. Laboratories can and do make mistakes. Some of these can be easily discovered if you do your own due diligence. All these measures should ensure that gold analysis values from successive campaigns and from different laboratories meet acceptable levels of accuracy and precision, and can be correlated together, particularly when they occur in neighboring holes. This is essential just as much for prospect evaluation as for project feasibility."

Jan 1, 1998

By Michael Sudbury

Introduction The essence of a good presentation is said to be: Outline what you are going to say Say it Summarize what you said This is perhaps especially good advice at 8.30 a.m. So here goes: This is an attempt to put numbers on three inextricably linked subjects: People and the Future Irrigation and Agriculture Mine Water and Mine Waste

May 1, 2013

By M. F. Goudge

This paper is intended to call attention to the manifold uses of limestone in industry; to indicate the types of limestone desired by some of the large consuming industries; and to give some information on the resources of limestone in Canada, so that an idea may be obtained of the present and future possibilities for limestone production. The word limestone is used in the usual broad sense to include both high-calcium limestone and the highly magnesian variety known as dolomite, as well as all intermediate types. Lime is simply calcined limestone, and in this general paper its uses have been included with those of raw limestone. It is of interest, in dealing with this subject, to glance back over the early history of the utilization of limestone, for by so doing we see that limestone has been of importance to mankind since the beginning of civilization and has contributed in no small measure to the development of a number of the arts and sciences. One of the first uses, if not the first use, of limestone was in connection with the making of lime for plastering purposes. This use antedates civilization. In the day of the ancient Greeks and Romans, the art of plastering had been brought to a state of perfection that is not nearly approached by the modern artisan.

Jan 1, 1930