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By C. -K. Fang, T. H. Chuang

"Temperature effects on the erosion of the 6063 aluminum alloy were investigated. Erosion experiments were performed by sandblasting silicon carbide particles of 80 grit size. The target volume loss, and worn depths of the eroded material were investigated at different temperatures. It was found that the temperature had only a minor impact on the peak attack angle. The effect of temperature on erosion damage depended on the relative humidity (RH) of the environment. IntroductionThe synergy of wind and sand or dust may result in the erosion of materials. However, the severity of erosion damage in different areas and in different seasons might be varied, depending on environmental variables such as temperature and humidity. As a result, determining the effect of environmental variables on erosion damage is important in selecting or ranking materials for their suitable applications in diverse areas.The relationship between erosion wastage and temperature is governed by many factors including temperature dependent properties of the material (strength, ductility, toughness, and dynamic hardness, etc.), mechanical erosion characteristics, the rate of oxidation, and the mechanical properties of oxides. Although the effect of temperature on erosion has been studied for engineering materials (Smeltzer et al., 1970; Gat and Tabakoff, 1978; 1980; Levy et al., 1986; Levy and Man, 1986; Chinnadurai and Bahadur, 1995; Howard and Ball, 1997; Colclough and Yeomans, 1997; Suckling and Allen, 1997), published literature dealing with aluminum alloy is rather limited."

Jan 1, 2000

By C. M. Campbell

In his report on the Coal Resources of Southern Vancouver Island, Mr. J. D. MacKenzie stated that: "For various reasons it has been imagined that the coal deposits of Vancouver Island are extremely large and readily available." "Unfortunately," he added, "neither of these assumptions is correct." The chief disability under which the Island mines now labor does not concern the extent of the deposits. There is ample coal for the present demand. It does, however, concern the availability of the coal. If it were readily available the fuel-oil competition would not be serious and there would be no competition with Alberta, American, Welsh, or Australian coal along the Pacific Coast, for Vancouver Island coal could be produced at a price that would cut out all competition. The outstanding operating difficulty common to all Island mines is the extreme irregularity of the coal seams. To most people a coal seam is synonymous with uniformity, and in most coal seams a condition found at one point will be repeated at other points in the same seam throughout the basin. The accompanying drawings show how very far this is from being true in the Cassidy mine, which, in many respects, is typical of Vancouver Island mines. Figure I is a plan covering about 160 acres of the Douglas seam, the only workable seam in this part of the district. The area shown represents what has been the best producing part of the mine and indicates the very large percentage of the seam where the coal is either entirely lacking or so small in amount that it cannot be profitably recovered.

Jan 1, 1924

By A. J. Antony Chettupuzha

During a construction project, it is important to ensure that accurate and pertinent knowledge is delivered on time to appropriate personnel. The criticality of documents exchanged or referred to by various parties, evolves over the course of the project lifecycle. Determining the criticality of documents at different stages of the project can aid companies with managing the flow of information in an organized manner, while providing for the detection of potentially disruptive, erroneous material that could result in delays and costs. Therefore, it is crucial to determine documents which have the potential to disrupt a process (by virtue of being incorrect versions etc.) so that they may be isolated or prevented from entering or interfering with the active flow of information in a project, while also ensuring standard revisions of documents are recognized and accessed accordingly. Electronic Product and Process Management [EPPM] systems provide the capability to establish and map information flow between different parties in a construction project. Analyzing an EPPM system may yield information about the criticality of certain documents within an activity, as well as isolate characteristics peculiar to documents which can assist in risk mitigation. We propose methodology that identifies such critical documents.

Aug 1, 2013

By A. Burduk

The traditional approach to managing information flow between a mine underground and overground, applied in copper mines of KGHM Polska Miedz S.A., is mostly based on exchanging spoken information using the mine telephone network and printed documentation. This way of information flow significantly influences effective use of time of a shift foreman employed at a mining division. In order to minimise multiplication of significant information generated as paper documentation, a concept of an IT system module to input basic data concerning operation of the mining division was developed. The idea is based on computer software that permits inputting data in the underground and their immediate sending to the overground. The above-mentioned solution will permit significant reduction of administrative work time that each foreman has to do on each shift. The time saved on filling forms and communication will permit the foreman and the other workers involved in information flow to spend more time for execution of their basic duties. In the case of the supervision employees working in the overground, the IT system will allow all the interested persons to be informed directly, with no necessity to transfer the information on the situation in the given mining division by turns from one to another. On the other hand, saving time on administrative works will permit the foreman employed in the underground executing more detailed inspection of workplaces in his subordinate mine division. Thus, availability of the foreman for the mining division operation will be improved. KEYWORDS

Aug 1, 2013

By Jennifer Young

Presentation Outline ? Introduction ? Aboriginal Inclusiveness ? Common interpretations, practices ? Aboriginal Community Expectations ? Lessons Learned ? Native Code of Conduct Introduction Jennifer Young ? Nestu'et (Mi'kmaq) means: becoming wiser, becoming more knowledgeable Aboriginal Inclusiveness ? Internal hiring strategies (affirmative action) ? Incorporating cultural awareness programs ? Approaches in governmental/organizational policy development Practices in negotiating economic development and fiscal sharing strategies

May 1, 2010

By Cheryl L. Allen

The power required to operate a ventilation system can be 25% to 50% of the total energy requirements of a mine. In an effort to reduce energy consumption, initiatives are being introduced at Vale Inco to increase the efficiency of ventilation systems with the objective of decreasing energy usage. One energy conservation measure being introduced is the use of variable frequency drive (VFD) technology for fan motor control. Advancement in technology is making VFD applications more of a standard in industry. The benefits include improved operating performance and system control, reduction in current peak demand, and optimized power usage. This paper describes the application of VFDs for main and auxiliary mine fans; and associated potential energy savings.

May 1, 2009

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 Jerry Danni

In order to remain viable today, corporations must view the environment as a strategic issue, and integrate environmental management throughout the organization. Corporate programs that used to be based primarily on regulatory compliance now must emphasize strategic environmental management systems, and must integrate these environmental systems with basic business functions. The mining industry today is global, and must have an organizational structure that can embrace different cultures, physical settings, and regulatory regimes. Sound environmental management practices are not different from good management principles. An effective environmental management system should be a complementary system to an organization?s overall management framework, integrated and aligned with the existing management structure. Integrating environmental management into core business functions is just good business. An effective environmental management system is a critical component of a company?s commitment to environmental, social and economic accountability. This paper presents the elements of the Kinross Gold Corporation strategic environmental management system and discusses the integration of the environmental management system into the core business functions throughout the Company

May 1, 2003

By G. S. Hume

Introduction O WING to the mineral discoveries which have recently been made in the Great Bear Lake region and the possibility of the need for fuel for transportation and development, it seems.timely ro review available information regarding the oil prospects in the vicinity of Great Slave lake and Mackenzie river, where a vast area is underlain by Palreozoic and younger sediments that undoubtedly are petroliferous. Exploratory surveys were carried out in this area by the Geological Survey and others in the latter part of the 19th century, but it was not until 1920, when drilling for oil actually began, that any serious attention was paid to the oil prospects. This is readily accounted for by the remoteness of the region, the lack of quick transportation facilities, and the shore summer season. Numerous and copious oil seepages had been reported, however, from widely separated localities, and interest was stimulated by the knowledge that these occurred in Devonian strata which had given a remarkable record of sustained production of high-grade oil in the oil-fields of southwestern Ontario. . Accordingly, during the four years 1920 to 1923, inclusive, several parties sent out by the Geological Survey made as thorough an investigation of various parts of the area as seemed warranted at that time, and from these surveys most of our information regarding the details of the stratigraphy is derived. In such a large area, it is inevitable that the lithology and thickness of rocks of the same age would show wide variations, and hence it should be recognized that conditions as regards oil prospects in the vicinity of the west end of Great Slave lake are quite distinct from those that occur near Fort Norman, 400 miles farther to the northwest, and these again are in all probability quite different from those in the less well known Arctic Red River area, 250 to 300 miles still farther north.

Jan 1, 1932

By G. H. K. Pearse

Sulphur is derived from both 'voluntary' and 'involuntary' production. The former category includes sulphur obtained from elemental sulphur deposits and from pyrite and gypsumanhydrite deposits. Sulphur in the latter category is produced by pollution abatement at fossil Juel plants and from treatment of metallic sulphides. Canada is the world's largest sulphur exporter and third largest producer. Main resources of Canadian sulphur are sulphurous fossil fuels, metallic sulphides and native sulphur. Only the first two sources have produced sulphur in Canada 10 date; the first source accounts for over 85% of total Canadian production. Future sulphur sources will be derived increasingly through pollution abatement and decreasingly through voluntary production.

Jan 1, 1984

By C. Pawlik, R. T. Jones

Cobalt occurs together with copper in the southern African copper belt, and a large portion of this cobalt ends up in copper smelting slags, mostly dissolved in oxide form. It is possible to achieve high recoveries of cobalt by reductive smelting of the copper slags, using some form of carbon as a reducing agent in an electric furnace. For example, a 40 MW DC arc furnace was operated at Chambishi Metals in Zambia from 2001 to 2008, and demonstrated cobalt recoveries of around 80% from slag to an iron-rich alloy containing copper and cobalt. The alloy was atomized prior to leaching. With the recent increase in demand for cobalt (and the resulting high metal prices), there has been increasing interest in this process route. There is also an alternative hydrometallurgical process for recovering the valuable metals from the slag. The choice between these process options requires a trade-off between capital and operating cost and environmental acceptability. This paper examines the potential for cobalt recovery from slags, and outlines various process options. INTRODUCTION Cobalt has had a number of important uses in society since antiquity, and its principal use has changed dramatically over time. Since at least 2250 BC, cobalt-based pigments (cobalt blue) have been widely used to colour manufactured goods such as glass and pottery. Later, cobalt became known for its magnetic and wear-resistant properties and high-strength alloys, and most of the cobalt produced was consumed in the production of cobalt-based superalloys. The greatest recent growth in cobalt demand is due to it being essential to the rechargeable lithium-ion batteries used in consumer electronic devices and increasingly to drive electric vehicles. Cobalt is usually produced as a by-product of copper or nickel. The copper belt in the Democratic Republic of the Congo (DRC) and Zambia supplies most of the world's cobalt production. In 2018, the DRC was expected to produce 90 000 tons of the world total of 140 000 tons of cobalt (Shedd, 2019). This paper focuses on the southern African copper industry, and specifically the cobalt that is able to be produced as a co-product from this. A BRIEF HISTORY OF SOUTHERN AFRICAN COPPER SMELTING Copper deposits in South Africa have been documented since at least 1685, when the Cape governor, Simon van der Stel, ‘discovered’ the 'Copper Mountain' at Springbok. South Africa's first public commercial mining company (imaginatively called the 'South African Mining Company') was established in Cape Town in 1846, to exploit the rich copper resources that were believed to exist in Namaqualand.

Jan 1, 2019

By Arnaud Faucher, Amar Sabih, Sudarshan Martins, Tristan Martin, Sami Makni, Peter Radziszewski, Poorya Hosseini, Francois-Raymond Boyer

The measurement of acoustic signals produced by a tumbling mill has been previously used to determine the operating state of the mill and correlate the variations of the sound intensity with the operating conditions of the mill. Separately, the discrete element model (DEM), a software simulation of the mill, was developed to provide insight into the operation of the mill. Presently, there has not been much work reconciling the DEM simulation of the mill with the acoustic signal. Working from basic principles of linear, time-invariant systems, agreement between an acoustic DEM simulation and the measured signal is sought. First, the impulse response function of the mill is measured. The DEM provides the forces applied to the mill shell as a function of time. A convolution of these simulated shell forces and the transfer function gives the simulated acoustic signal. This signal is compared to the measured acoustic signal, both in the time domain and the frequency domain. Finally, a discussion of the results is given.

Jan 1, 2012

By D. Ferrand, C. Villeneuve, N. Bensalah

"La conciliation entre l’expansion de l’industrie minière et les exigences du développement durable représente un grand défi. Face aux différentes controverses touchant cette industrie, la dernière décennie a été marquée par une plus grande mobilisation de l’ensemble des parties prenantes. Cependant, plusieurs carences persistent en matière d’opérationnalisation du concept de développement durable. Ce défi met en cause la responsabilité partagée entre les parties prenantes. Il exige le renforcement des responsabilités gouvernementales et l’instrumentalisation de bonnes pratiques de responsabilité sociale des entreprises. En aval, s’impose la gestion intégrée de l’usage des produits miniers et la promotion de l’innovation et de la recherche.ABSTRACT Conciliation between expansion of the mining industry and sustainable development requirements represents a great challenge. With regards to the various controversies touching this industry, the last decade was marked by a great mobilisation phase of all stakeholders. However, there are still many shortcomings regarding operationalization of the sustainable development concept. This challenge involves shared responsibility between the stakeholders. It requires strengthening government accountability and instrumentalization of good corporate social responsibility practices. Further down the chain, the use of mining products and the promotion of innovation and research must be achieved through integrated management."

Jan 1, 2015

By Xuehui Xia

Abstract -There are a number of sedimentary exhalative massive sulfide (SEDEX) deposits in the Proterozoic Langshan-Zhaertai rift at the western segment of the northern margin of the North China platform in China, including more than ten large, medium and small deposits located in a belt of 300 km EW by 50 km to 100 km NS, with large Cu, Pb, Zn, Ag, and S reserves. In several representative SEDEX deposits in the rift, the mineralizing elements are prominently zoned, horizontally or vertically, with Cu decreasing but Pb increasing from west to east, Cu decreasing but Zn increasing from bottom to top, and Zn restricted to the bottom half. The ore-hosting rocks, characterized by a clear manganese halo, have developed a polymetallic mineralization in positive relation with their carbon contents. Their isotopic aspects are: ?34S has relatively large positive values, fluctuating between +5‰ and +35‰, compared with Pb isotopic compositions which are less variable, with a model age of 1600 Ma to 1800 Ma, showing that they are mantle-derived. The mineralizing materials were associated undoubtedly with the contemporaneously faulting events in the rift. The deposits owe their origin to seafloor exhalation, with sedimentary rocks as their hosts.

Jan 1, 1999

By Edouard Masengo

A long dyke will be constructed in a lake with rockfill placed by end dumping method. Its crest will be at elevation 521.5 m compared to the nominal lake level at 520 m. In the first portion, its height will vary from 1.5 m on a 35.1 m thick tailings layer to 18.3 m on about 0.5 m of tailings. In the second portion, the dyke will be built on native silty clay and will vary from 18.3 to 15.2 m in height. The tailings consist in stratified layers of fine-grained soils showing lateral and vertical segregation. The tailings are compressible and may develop excess pore water pressure on loading. The tailings overlie a thin layer of relatively soft native silty clay. The till beneath the silty clay is considered incompressible compared to the material above. After construction, as the tailings and silty clay consolidate, pore water pressures will dissipate and dyke stability will improve. Since dyke stability will increase with time, the primary concern is its stability during construction. As a result of construction activities, three potential modes of failure were identified and recommendations were provided regarding the measures that should be undertaken to increase dyke stability during construction.

May 1, 2003

By D. R. Griffiths

"Oxidation of pyrrhotite prcxiuces sulphuric acid which in turn leaches out heavy metals, resulting in acidic contaminated seepages. The establishment of a marsh on top of the pyrrhotite would result in an anaerobic sediment, which should prevent further oxidation of the pyrrhotite. Initial data indicates that concentrations of sulphates and heavy metals in the seepage water are greatly reduced. Further hydrogeological studies are required however, to determine if metal and acidic loadings to the environment have increased.L'oxidation du sulfure de fer produit de l'acide sulfurique qui a son tour attaque les métaux ayant pour resultat une contamination d'acide et de métal des eaux d'infiltration. L'etablissement d'une couverture faite de boue et de vase au-dessus du depot du sulfure de fer réduit les effets de l'oxidation.Les données initiales indiquent que les concentrations de souffre et de métaux dans les eaux d'infiltration sent grandernent réduites.Des études plus poussées sent nécessaires pour déterminer si les quantités de souffre et de métaux dans les eaux d'infiltration ont augmentées.INTRODUCITONPyrrhotite tailings are readily oxidized through a combination of precipitation and atmospheric oxygen causing acidification of the unsaturated zone above the water table. This reaction is usually catalyzed by the bacteria, Thiobacillus ferooxidans. As the pH decreases, heavy metals become more soluble resulting in contaminated seepages to ground and surface waters.By creating a marshland on top of the pyrrhotite, an anaerobic intermediate layer should form between the organic covering and the tailings, preventing the oxidation process from progressing.In September 1986, Falconbridge Limited implemented a tailing reclamation project that involved creating a marshland on top of pyrrhotite tailings. The following paper will discuss and illustrate the preliminary results obtained during the sampling period of May to September 1987."

Jan 1, 1988

By David L. Huston, Wouter Bleeker, Bruce E. Taylor, Ron Cook, Bob Stewart, Elizabeth R. Koopman

"Abstract-Detailed oxygen isotope mapping of rhyolites in and around the Kidd Creek mine indicates that the orebodies are associated with relatively low (<12‰) whole rock values that extend up to 200 m laterally from ore. The zone of low d18O values is overlain stratigraphically by a carapace of higher (>13‰) values that extends up to 1.5 km laterally from and 300 m to 500 m above ore. Immediately above the stratigraphically highest orebody this carapace is cut by a zone of lower d18O values extending from the ore zone. Zones of higher d18O values also occur in massive rhyolite bodies that occur in the footwall of the orebodies.The zone of low d18O values partly coincides with a Na2O depletion anomaly associated with hydrothermal alteration, except that the Na2O depletion anomaly has a greater lateral extent, and the low d18O anomaly extends farther into the stratigraphic hanging wall. These data suggest that d18O mapping may detect hanging wall alteration above massive sulfide bodies more effectively than conventional lithogeochemistry. Zones of high d18O values, which define zones through which large quantities of low-temperature hydrothermal fluids have passed, may also have usefulness in exploration.Oxygen isotope variations at Kidd Creek record three stages of a hydrothermal system that evolved in temperature with time, as follows: (1) an early, low-temperature event that produced rocks with high d18O values, (2) a high-temperature event that produced rocks with lower d18O values, and (3) a later, low-temperature event that also produced rocks with high d18O values. The high d18O sig- nature of the massive rhyolite was recorded during early-stage, low-temperature (<200°C) alteration, and was probably preserved owing to decreases in permeability associated with low-temperature silicification. The low d18O signature of cherty breccia and chloritite was recorded during the thermal peak at >300°C. High d18O values in the carapace above the deposit were recorded as the hydrothermal system waned."

Jan 1, 1995

By Michel Guillot

Gaz metal arc welding is commonly used for producing large frames and assemblies. Even for light aluminum and thin wall assemblies, the GMAW technique is increasingly preferred over the GTAW technique. This is particularly true where the welding gun motion is achieved accurately with automated or robotic systems and when using pulsed or regulated metal deposition. In this study, butt joints in floor welding position are tested at speed ranging from 1.5 to 16 m/min. Attempts are made of find parameters providing good and repeatable joint quality with minimal distortion and good appearance even at high travelling speeds. Taguchi experimental plans are proposed with different parameters tested with sheet metal samples. The parameters include typical GMAW machine settings, joint preparation geometries, wire gages, gun angles, wire feeds, and more. The robot motion speed and the proximity of the part are also considered. Direct monitoring of machine welding current and voltage is achieved. Once is found the best set of parameter settings, additional tests are carried out to verify the repeatability of weld quality. Secondly, these conditions are applied for joining and testing a floor panel made of several extrusions. Weld quality is established with Vickers micro-hardness measurements, cross section geometries of the weld pool including penetration, tensile tests and metallographic observations to establish the amount of porosity and weld microstructure in the HAZ.

Jan 1, 2011

By C. E. Cairnes

The Slocan mining camp in Kootenay district; British Columbia; has long been noted for the great number of its silver-bearing deposits; and for the success that has; in many instances; attended their development. The orebearing area lies east of Slocan lake and mainly within a radius of 6 to 8 miles of the mining town of Sandon. Within this limited area 135 or more properties have shipped ore in quantities of from 100 tons or less to more than 500; 000 tons; and with a total value in silver; lead; and zinc ranging from a few hundred dollars to well over $10; 000; 000. Of the three metals; silver has easily ranked first in value; with lead second and zinc third. Zinc production; however; made slow progress in the early years; and with . the exception of the Lucky Jim mine; and a few others where high-grade ore could be readily hand-sorted; was a detriment to the silver-lead ores until improved methods of separation enabled it to take an important place in the mineral production of the Slocan.

Jan 1, 1954

By Abdurrahman Tosun

It is very important for after blasting processes that muck pile fragmentation is predicted and controlled during blasting. Therefore, a significant research effort has been devoted to the development of mathematical equations that predict the value of average muck pile fragmentation. The specific charge parameter used in all of these equations is determined as the ratio of the total mass of explosives used to break a volume of rock. The length of blast surface and the row number of the blasthole are ignored in the calculation of the specific charge. However, in a blasting operation, blasthole geometry may result in additional material being impacted by a blasthole. This is due to effect shares of in both end sides of blastholes and the back region of blasting surface. In this study, a total of 14 blast tests, 8 at the first quarry and 6 at the second quarry of the Bati Anadolu (Western Anatolia) Cement Factory, were performed. In each study area blast tests were designed in the same direction continuously to provide stable structural properties of the rock. Therefore muck pile fragmentation depended on only specific charge values for each blast tests. Specific charge values were calculated according to both an average blasthole and also the total volume of material occurred as a result of blasting for each blast tests. During loading until the end of blasted material the front, the back, the arm off and the bucket off pump hydraulic pressure values occurred in hydraulic pistons of the loader were determined with a lot of data received for each blast tests. After that the relationships between specific charges values obtained according to two different methods and hydraulic pressure values of the loader were established with two correlations. The relationships between specific charges values obtained according to the total volume of material occurred as a result of blasting and hydraulic pressure values of the loader occurred as the best results especially the blasting operations that have the total length of blasting surfaces are short.

Aug 1, 2013