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By Silvio E. Kruger

Real time measurement of wear and corrosion provides crucial information needed to determine an optimal schedule for corrective maintenance and is a powerful tool to maximise equipment availability and reliability. It also leads to savings from optimized spare parts handling and helps to avoid costs of accidents and their negative impact on safety and the environment. This paper presents the technology of ?painted-on? ultrasonic transducers that can be integrated to structures and accurately measure the remaining thickness and therefore determine wear or corrosion losses. These transducers have a small footprint, a performance comparable to other commercially available ultrasonic transducers and can sustain temperatures as high as 400ºC. The application of this technology to mining equipments and its potential benefits are discussed.

Aug 1, 2013

By A. J. Paul Laprairie

"ADVANCE planning of mining methods, from the first development openings to stope layout and pillar recovery, has long been accepted as a normal method of operating a mine. Recently, mine managers have become increasingly aware that advance planning of cost and accounting controls can also be considered a normal method of operation. The use of such controls is wide-spread in manufacturing industries. In mining, the gold mines of South Africa have pioneered, with marked success, in this field and have been closely associated with most of the research and field work in accounting control. Canadian mine managers are also beginning to realize the advantages of using planned costs. The control procedures which subsequently have been introduced at various mines have come to be known by such names as ""Responsibility Costing"" or Budgetary Control"".Budgetary control, the term used in this paper, is based on the concept of decentralized authority with centralized control. ;The control is achieved by measuring results against yardsticks which are in the form of budgets or standards. Bud-gets are made for the future activities of each possible operation as planned by the department head, and attention is directed to variations from this plan. Furthermore, the control process charges to each operation only those costs which are incurred directly for that operation, and which can be controlled by the person in charge. Thus, budgetary control relates results to the officials responsible for those results. Expenditures are analyzed according to the organizational structure of the mine and the people who run it, and not according to production processes."

Jan 1, 1960

By A. Ghasemi

An alumina-silica coating was deposited on a nickel substrate by sol-gel process, and the structures and composition were evaluated, The sols were made from aluminium and silicon alkoxide, and an acid catalyst including HCl, To produce adherent silica coatings on nickel, various additives such as surfactant, viscose additive and drying control chemical additives were introduced to the system, and appropriate drying and firing cycles were applied after dipping in solution. The hot corrosion and oxidation resistance of the coating at different temperatures were investigated, The structure and uniformity of the coatings were examined by scanning electron microscopy (SEM), The results indicate that a uniform coating of alumina silica can be produced on a nickel substrate by optimizing the composition and process variables of the sol. Coatings can protect substrates from oxidation and hot corrosion at different temperature up to 1000°C, but is not very effective for hot-corrosion resistance at 1000°C.

Jan 1, 2005

"These guidelines have been prepared to assist the Qualified Person(s)in the planning and supervision of exploration programs which will be reported under National Instrument 43101. The Companion Policy of NI43101 references the guidelines and states that issuers and Qualified Persons should follow them.Exploration Best Practices GuidelinesPreamble: These guidelines have been prepared to assist the Qualified Person(s) in the planning and supervision of exploration programs which will be reported under National Instrument 43-101. Such exploration programs must be under the supervision of the Qualified Person who will be responsible and accountable for the planning, execution and interpretation of all exploration activity as well as the implementation of quality assurance programs and reporting. These guidelines are also recommended for use in the planning and execution of exploration programs which will not be reported under NI 43-101. This set of broad guidelines or ""best practices"" has been drawn up to ensure a consistently high quality of work that will maintain public confidence and assist securities regulators. The guidelines are not intended to inhibit the original thinking or application of new approaches, that are fundamental to successful mineral exploration.Results should be summarized and reported in a Technical Report of good professional quality in accordance with the National Instrument 43-101 and Form 1 contained in that instrument. All exploration work from which public reporting will ensue must be designed and carried out under the supervision of a Qualified Person (""QP""). A QP is defined in National Instrument 43-101 as an individual who is an engineer or geoscientist with at least five (5) years' experience in mineral exploration, mine development, mine operation or project assessment, has experience relevant to the subject matter of the project or report and is a member in good standing of a recognized professional association."

Jan 1, 2003

By J. R. MacDonald

MINING literature contains very few descriptions of operations producing as little as 25 to 30 tons of ore per day. The purpose of this paper is to discuss the gradual development of a mining method for such a small-scale operation at the No. 2 mine of Central Patricia Gold Mines, Limited, and in doing so to review several systems of stoping applicable to narrow ve1ns. MAIN ECONOMIC FACTORS TO BE CONSIDERED (1) Overhead.-The outstanding feature of most mines operating on a single narrow vein is chat of small daily tonnage. The reason for this low output can be readily understood. The strictly limited ore-reserves present a condition unfavourable for a policy of large initial expenditures, with the result that the capacity of the plant provided must be governed by the? amount of ore in sight at the time when mill construction is planned. This is immediately reflected in the cost per ton, there being relatively few tons over which to distributed the more or less static charges, such as hoisting, heating, supervision, administration, pre-production expenses, and other write-offs. (2) Development.-In mining this type of orebody, the main factor contributing to high costs is unquestionably the small tonnage of ore made available by a given amount of development. Thus, for example, from the data tabulated below it can be seen chat, assuming a 12-in. vein and a drifting cost of $9.00 per foot, the development charge for this item alone would be 71 cents per ton. Add to this the charges for raising, cross-cutting, shaft-sinking, and pumping, besides charges arising from development in waste, and the figure will be very considerably higher than 71 cents.

Jan 1, 1941

By Torsten Zeller

Due to the increasing worldwide demand for raw materials and the resulting rise in commodity prices more expensive processing that is able to utilize complex ores becomes economically viable. This and increasing ecological awareness is why the interest in recycling and urban mining is steadily growing in Germany. In addition to that; landfills do also contain elements, which were not targeted over the period, when they were being accumulated. Examples are rare earths, indium, gallium, cadmium, arsenic, selenium and tellurium. Also copper, zinc and lead, the target components of ancient mining, can be obtained due to more effective processing and smelting technologies. Funding by the German Federal Ministry for Education and Research, entitled "r³ ? Strategic Metals and Minerals ? Innovative Technologies for Resource Efficiency" also indicates the high level of strategic interest. It is against this background that the research project "Exploitation of the Raw Material Potential of Mining and Metallurgical Tips in Respect of Sustainability as Exemplified in the West Harz Mountains (ROBEHA)" has been implemented. A major concern of this project is the possible transfer of results to landfills in other areas. Therefore the development of an expert system based on the innovative processing methods and a method manual for urban mining are the central components of the investigation. This will provide an important contribution to the cost optimization of ensuing urban mining projects. To ensure the success of landfill mining projects it is necessary to record the composition and quality of the deposits accurately. Also the environmental impact caused by landfill mining and changes in the natural and cultural landscape will be considered in a multicriteria evaluation method. Depending on their origin the tips are divided into the categories mining, processing, and smelting. The content of a landfill and thus the economic potential in terms of urban mining is dependent on the type and composition of the deposits (host rock, gangue, and ore mineral), the available processing and smelting technology, and the target components at the time of mining. Zinc, for example, was not been processed until the 19th century, when it gained attention as being material of economic importance. After such knowledge about a landfill is obtained the decision for further investigations can be made. For a total of 158 landfills in the Harz Mountains, both the volume and the approximate contents of copper, zinc, and lead has been estimated for the different types of tips within past research projects. Based on the prices of the London Metal Exchange (LME) and a euro/dollar exchange rate of 0.76 (as of 03/05/2012) and assuming a minimum density of ? ? 1.5 t/m³ a average value of 1.6 billion ? in copper, zinc, and lead can be obtained. Although only these three metals are considered in this first estimate, it demonstrates the potential of landfill mining and the need for further research. KEYWORDS Urban Mining,

Aug 1, 2013

By Yue hua Hu, Wei Sun, Pan Chen, Li Wang, Runqing Liu, Central South University

"The flotation separation of muscovite from quartz was investigated using mixed sodium oleate/dodecylamine (NaOL/DDA) collectors. The flotation experiments were conducted on single minerals and their collecting performances were studied by means of adsorption amounts and molecular dynamics simulation. Flotation results show that muscovite presents good floatability while quartz exhibits poor floatability in alkaline condition. Adsorption amounts show that both NaOL and DDA can absorb onto surfaces of muscovite and quartz in presence of mixed surfactants. Molecular dynamics simulation indicates that DDA plays an important role in the adsorption of mixed surfactants on these two mineral surfaces. The molecules of mixed NaOL/DDA are arranged in a rigid and well-ordered packing on muscovite (001) surface. Only a few DDA adsorb on quartz directly, and rest DDA and NaOL molecule exist near by the quartz surface, forming a hydrophilic cylinder-like structure. This study may provide guidance for the flotation mechanism and application of mixed anionic/cationic collectors.INTRODUCTIONIn the past decades, there has been an ever-increasing demand for muscovite (KAl2(Si3Al)O10(OH)2) because of its potential applications in cosmetics, construction and metallurgy industries (Barlow & Manning, 1999). Besides, muscovite is an important carrier for some rare metals, including vanadium, titanium and lithium (SsuerrN, 1979). Quartz (SiO2) occurs as the main gangue mineral in muscovite ores, which results in a low purity of muscovite and limits its wide applications. Therefore, there is an urgent need for the beneficiation of low grade muscovite ores. Many studies remove quartz by screening and gravity separation in virtue of their differences in shape, hardness and density. However, these methods undergo poor efficiency in case of small particle size (below 50µm) of muscovite and quartz (Liubakka, Sullivan, Lamphere, Corradi, & Dykhuis, 2011; Santos, Franca, & Ogasawara, 2011)."

Jan 1, 2016

From 1999 to 2008 rock related accidents accounted for 75 fatalities, nearly 6,000 injuries and almost 14,000 incidents (Pappas and Mark, 2011). Clearly this shows that rock related safety on coal mines remains a serious issue and more effort is needed to address this hazard. This paper reviews support design considerations and monitoring needed to improve rock related safety in room and pillar coal mines in the USA. From the present study design considerations continue to evolve and improvements in technology and a better understanding of failure mechanisms and methods to prevent these failures from occurring are in place. At first glance, the design of safe and efficient underground openings appears simple until the designer begins to realize the complexities and variability of geometries, geology, loading and stress influences, support designs and other factors such as corrosion and economics. Ultimately the goal of all designs is to ensure that it can be completed safely, last for the duration of the design life and it is economically feasible.

Aug 1, 2013

By A. J. Sinclair

"Abstract-Geology contributes essential information toward obtaining high-quality resource/reserve estimates. In this context, geology can be considered under the following overlapping topics: regional geology, detailed (deposit) geology, mineralogy, ore deposit models and continuity, with geological mapping being fundamental to all. Each of these topics is considered here in terms of potential contributions to "improved" mineral inventory estimation. Some of the principal conclusions are:1. Regional geological relations must be consistent with deposit geology. It is common that important geological relations are more clearly evident in various regional locales than in highly altered and/or highly deformed mineralized areas containing mineral deposit.2. Detailed geology provides information for a geometric model of a deposit, a model that serves as a basis for mine planning. It is important to distinguish fact from interpretation in such models. Substantial effort is required to characterize the geometric margins of a deposit and the relation of these margins to the simplistic geometric form that normally emerges as an interpretation.3. Mineralogical studies relate to many aspects of deposit evaluation including abundance of ore and deleterious minerals, spatial distribution of ore and deleterious minerals, grain size characteristics of important minerals, mill design, etc.4. Ore deposit models contribute substantially to confidence in developing a three-dimensional geometric model of a deposit for mine planning. Specifically, they are a basis on which to develop rules for interpolation and extrapolation of ore, and they contribute to recognition of domains, each with its own characteristic continuity and margin character.5. Continuity is dependent on mineralization style and may be controlled structurally and/or chemically. It is important to distinguish geological continuity and value continuity. A wide range of classical geological methods are useful in examining geological continuity; value continuity is best viewed as a statistical characteristic that is quantified by any of several measures of autocorrelation."

Jan 1, 1998

By Francisca San Martin, Tomas Vargas, Willy Kracht

"In Cu-Mo deposits it is usual to find considerable amounts of pyrite (FeS2). When processing this kind of ore by flotation, pyrite is rejected using lime to increase the pH to alkaline conditions (pH ~10.5). In the case of using seawater without pre-processing, i.e., raw seawater, the lime consumption increases dramatically and the recovery of molybdenite drops due to the precipitation of magnesium hydroxide on its surface. In order to avoid these negative effects, alternative ways of depressing pyrite should be considered.The current work introduces the use of Acidithiobacillus ferrooxidans, bacteria commonly used in bioleaching, as an alternative to depress pyrite in seawater flotation. The paper presents the results of biodepression in three systems: fresh water, water with added sodium chloride at 35 g/L (which corresponds to the salt concentration in seawater ) and seawater. The results show that it is possible to bio-depress pyrite with A. ferrooxidans in natural seawater pH (7.8-8.2). A similar behaviour is observed when running the experiments in fresh water, and in water with sodium chloride added.INTRODUCTIONWater is a scarce but essential resource for human development. The main reason for this scarcity is that, although 70% of the earth's surface is covered with water, only 3% of the total is fresh water and an important part of this water is frozen, so that only 1% of fresh surface water can be used for human activities. In Chile, most of the mining activity is concentrated in the north of the country, located in the Atacama Desert, considered the world's driest desert. That is why some mining companies have chosen to use seawater in their processes. For example, Esperanza (Antofagasta Minerals), and Sierra Gorda (KGHM International) use raw seawater in their flotation processes."

Jan 1, 2016

By W. J. Stickney

"Over-all recovery of cadmium has been increased at the plants of the Hudson Bay Mining and Smelting Co., Limited, since the construction of a slag fuming plant and baghouse where smelter flue dust is recovered. This pa-per outlines the distribution of the cadmium in plant products from the concentrator to the refining department.The leaching of cadmium-bearing precipitates from the zinc plant is also discussed. This consists of a two-stage leach; first with sulphuric acid and then with copper sulphate. Details of the leaches are outlined along with the safety measures practised in handling the hydrogen and arsine evolved.The paper describes the final preparation of electrolyte for the refining cells by purification for copper and thallium. Deposition of cadmium, using a polyacrylamide as an addition agent, is discussed.An outline is given of the melting procedures, under either sodium hydroxide or zinc chloride, and of the sub-sequent treatment of the dross to recover entrained cadmium and thallium."

Jan 1, 1966

By Shae K. Kim

The aim of this study is to manufacture magnesium alloys with alkaline earth metal oxides (BeO, CaO, MgO or SrO) additions with the objectives of (1) ensuring safety during processing and applications by raising the ignition temperature and reducing oxidation, (2) protecting the environment by reducing or eliminating use of protective gases, (3) maintaining or improving elevated temperature properties with lower amount of Ca or Sr or rare earth metals when compared with conventionally developed high-temperature magnesium alloys, (4) developing cleaner strip casting and continuous casting processes without hot tearing and (5) obtaining all of these objectives without sacrificing mechanical properties or increasing the cost of magnesium alloys.

Jan 1, 2006

By A. Gillis, J. Keyes

"This is a prelirr1inary report on automatic control at East Malartic Gold Mines.After installation of the cyclones in the East Malartic grinding circuit, the interest was aroused in the automatic control system for the circuit. Investigations were made as to the possibilities of such an installation. This resulted in a preliminary survey of the circuit by Milltronics Ltd and an analysis of the circuit by Mines Branch personnel. A study of the investigation and analysis indicated that a cost reduction and improved efficiency could be expected by the installation of an automatic control system in the grinding circuit. It was also indicated tl1at such installation should pay for itself within a year. This was the point that sold management on such installation. The need of three operators was expected to be eliminated .The installation was to consist of a central control panel, microphoncs on each mill, regulation of feed rate, pneumatic valves for addition of solt1tions, density control of the cyclone overflow, which is a grinding circuit product, rod mill feed box plugging detector and a conveyer weightometer for tonnage indication and control.As well as the elimination of one man per sl1ift, other benefits which were to be received but unable to estimate were: 1) More tonnage per clay by operation of the mills at the proper capacities. 2) Lower grinding costs. Less under-loading should result in less steel wear and lower pumping cost. In the condition of overloading, a coarser grind is obtained resulting in greater impeller and liner wear. The overloading and underloading showed up on the n1icropl1oncs. 3) An improvement in the recovery as a result of less over-load. The tailings loss from a coarser grind are not as frequent."

Jan 1, 1965

By Mikael Ramström

The IREDES Special Interest Group (SIG) for Drill rigs has been active since its inception at MineExpo 2000, in Las Vegas USA. The SIG for drill rigs is responsible for the development of a IREDES Drill rig profile. This includes the exchange of production planning, performance and quality reporting data between various kinds of drill rigs and the databases used by the operating mine. During year 2001 a first draft of the drill rigs profile was jointly prepared by drill rig suppliers, mining companies and third party suppliers and reviewed during several SIG meetings. In mid 2002 the profile was released for prototyping projects and since then, feed back received from these projects has been used as input to the first official IREDES release. LKAB and Atlas Copco decided in 2002 to start an IREDES prototyping project using the Simba L6C production drill rig as target equipment. The goal was to verify the drill rig profile and identify possible problems prior to the official release. This was done by implementing the IREDES prototype version in the LKAB?s production planning system and Simba rig control system. The Simba rig control system was designed to handle drill plan and logging information coming from the mine planning system. In parallel to this the mine production system was adapted for drill plan export and logging data import on IREDES format. This paper presents the most recent results of this prototyping project. Result from late 2002 show that the basic architecture of the drill rig profile works and that a common language for data exchange, IREDES will be a central issue for future mine automation. As a result from this and other IREDES prototyping projects the official IREDES release will be available in 2003. Soon after that release IREDES compliant products can be expected. This will include drill rigs and mine production planning systems.

May 1, 2003

By Curtiss O. Ehrsam, M. Naseem Mian

Alaska’s Red Dog Mine is strengthening its position within Cominco’s “Vision 2000”strategic plan by continually improving quality and quantity of production while reducing costs. Red Dog has evolved into a stable and mature operation, after six years of milling experience. A high grade, partially oxidized orebody in the severe Arctic environment, along with competing producers in a volatile metals market, are the continuing challenges facing Red Dog. The Red Dog Mine is striving to meet these challenges with emphasis on operator training combined with creative systems development and increased production. This paper describes developments in operations along with future plans.

Jan 1, 1996

By Siavash Zamiran, Abdolreza Osouli

"One of the most concerns of room and pillar mining system is subsidence of the ground surface due to coal mining particularly in room and pillar mines. Subsidence of ground surface is a result of floor, pillar, or roof failure of the mine. At the same, due to many difficulties associated with surface disposal facilities of coal refuse, some mining companies are trying to use underground space as a disposal storage place. In this study, stability and subsidence analyses of an underground coal mine located in the Illinois Basin are conducted. This room and pillar mine was abandoned and later on was used as a storage place to accommodate the coal fine refuse with slurry backfilling method. The geological stratigrophy and geomechanical properties of the mine floor and roof were collected. Floor and pillar stability analyses were conducted for areas with various extraction ratios. The stability of the mine was evaluated both prior and after slurry backfilling. The floor and pillar stability analyses results of the mine due to moisture exposure after slurry backfilling are discussed. The subsidence potential due to mine failure is also evaluated.INTRODUCTIONA typical lithology of coal seams in the Illinois Basin consists of weak underclay stratum. The immediate weak underclay causes frequent floor instability problems in Illinois underground coal mines. There are two different stages in assessing floor stability of the mines where slurry backfilling is planned. The first stage is during the mining operation when weak underclay layer squeezes under pillar stress and results in punching or bearing capacity failure. The second stage is after slurry backfilling. During this stage, the slurry material soaks non-durable floor layers and causes strength reduction in floor material. Pillar stability conditions should also be taken into account during both the operational period and after the slurry backfilling."

Jan 1, 2015

By O. Moselhi

Material can be seen as the fuel needed to execute the project from inception to completion. Material installed provides good indicators of progress achieved onsite vis-a-vis project schedule performance. It correlates well with the role of the schedule performance index (SPI) of the earned value method (EVM). Material is recognized to have a significant impact on achieved progress for physical completion of project activities. This paper presents a study on the development of material status index (MSI) in support of the EVM. Unlike the SPI, the newly developed index account for the criticality of project activities. This is carried out considering the total float of each activity, percent float (i.e. the ratio of float to activity duration) and the total float of the path on which the activity is located. MSI, can independently and jointly with SPI provide root causes behind problems encountered during project execution. In turn MSI can reveal material related factors behind the performance detected by joint interpretation of the two indices. MSI serves to provide added value in alerting management to take corrective actions. While SPI and MSI may have different values, they can jointly augment and enrich the captured project status based on EVM. To demonstrate the capabilities of the developed MSI method, it is implemented on a case study. The case encompasses the construction schedule of a hydro power station constructed in northern Quebec. Different scenarios are adapted from the real case to demonstrate a set of practical aspects of the developed index. The results generated from the analysis of the case study illustrate the useful features of MSI beyond those of the traditional SPI on two fronts; causation and the considerations of criticalities of actives.

Aug 1, 2013

By R. M. Berry

A brief outline of refining methods used to (1) upgrade yellowcake to nuclear purity and (2) convert the uranium to the chemical and physical forms required by the fuel fabricators is presented. The uranium hexafluoride (UF6) production facility now under construction at Eldorado, Port Hope, is discussed. Technological improvements in uranium refining are considered.

Jan 1, 1969

By C R. Evans

Whole-rock and muscovite potassium-argon dates from selected low-grade metamorphic rocks of Precambrian age in the Canadian Rocky Mountains near Jasper, Alberta, were obtained to ascertain the age of the source terrain and the age of the metamorphism. Ten argillites gave whole-rock dates ranging from 270 to 485 million years, dates which are apparently inter-mediate between the age of the source material and that of the metamorphism. "Up-dating" increases with the degree of orientation of muscovite in the cleavage plane, and with the ratio of the muscovite in the cleavage plane to that in the plane of the bedding. Detrital muscovite from four arenaceous rocks gave dates ranging from 1,050 to 1,780 million years. "Updating" increases with decreasing grain size, so that, within the range investigated, the cube of the median diameter (¢) of the muscovite is apparently proportional to the radiometric date.

Jan 1, 1964

By G. R. Peeling

The Mining Association of Canada launched the Towards Sustainable Mining initiative in 2004. TSM's goal is to improve the mining industry's performance by aligning its actions with the priorities and values of Canadians. The initiative currently includes performance indicators for four areas: tailings management, energy use and greenhouse gas management, external outreach and corporate crisis management planning. Over the past year, the association has been designing a performance assessment and verification system for these performance areas, as its members prepare to move external verification of their performance in 2007. The initiative and its evolution, as well as the challenges faced in developing a verification system applicable to an entire sector will be examined.

Jan 1, 2007