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By Jack F. McQuat, Ross D. Lawrence

"Most geologists and mining engineers, in the course of their professional careers, frequently become involved with the appraisal of metalliferous mineral deposits and develop a familiarity with and standard approach to the evaluation of these deposits. When the same individuals approach the industrial mineral field, however, their usual approach pattern can be rudely disturbed.This paper highlights the difference in appraisal approach and outlines the factors common to both but which have entirely different emphasis. These comprise geological appraisal, analytical requirements, the importance of transportation, marketing requirements and standards, including appropriate allowances for product development, and marketing penetration.Out of these ""different"" considerations, however, a pat-tern or standard approach emerges which is as common to the industrial mineral field as that used either consciously or subconsciously in the metallic field.The paper reviews the different factors and points of emphasis and offers an outline of the common pattern of appraisal for industrial minerals."

Jan 1, 1971

By Allan F. Lawrence

"I AM SURE you do not expect from me any learned dissertation on the problems and opportunities of the mining industry. Y our program committee must have recognized my limitations when issuing the invitation to speak to you, because they very thoughtfully left the subject wide open.With the leeway thus granted, I hope that you will bear with me for a few minutes while I try to clarify the impressions of the mining industry that I have gained in the very short time I have held the Mines portfolio and some of the parts that government bas or should have in furthering its development.As I see it, it is the duty of the Mines Department, as an arm of the provincial government, to balance the proprietary rights of all the people against the interests to whom the privilege of developing our resources are, in a s e n s e, leased. To strike a fair balance is not always easy, nor is it possible always to satisfy both sides. Still, under the free enterprise democratie form of government to which I think we al! subscribe, no better way of handling the problem has yet been discovered."

Jan 1, 1968

By Baisheng Nie

The process of gas diffusion through coal particles and the mathematical physical model under the third kind boundary condition was determined to obtain the rules of gas diffusion through coal particles of different sizes. The analytical solution of the equation was obtained by the Method of Mathematical Physics. The parameters of analytical solutions and the implications of parameters were analyzed. The Biot criterion (Bi) and the Fourier criterion (F0) of mass transfer can represent and reflect the features of gas diffusion field of coal particles. Moreover, the measurement method of gas diffusion coefficient and surface mass transfer coefficient is introduced and an example of measurement is given. The achievement can provide the support to prevent disasters related to methane in coal mines.

Aug 1, 2013

By Joanna LaForte

"IntroductionIn respect to The Human Dimension by M. Phyllis Bray, this author's impression is that research on long distance commuting (LDC) is long overdue. This type of mining is not new to many workers, especially those from areas such as the Maritimes, who have had to look for work away from their families for at least a decade. Perhaps to the industry the over-all set-up is new, but to workers who have faced mine shut-downs in their areas finding a job was the main objective and if the security of long-term employment was evident, then the families might join them later. This was the situation with which the writer' s family was faced.LDC LifestyleBeing the wife of an underground miner, the author has personally experienced this lifestyle for almost 10 years, and has never experienced accommodation in a company town. The first five years of marriage were spent in a small rural municipality within 50 miles of the worksite, but the town had industry separate from mining and was not affected by the mine shut-down.Since her LDC lifestyle began her family has been pretty much city-based, out-of-province commuters with two children and a third to arrive some years later. She therefore lived a fairly normal married life with a husband home daily. The author has experienced life with a husband who worked away for five-day stretches and then drove long distances to be home weekends or the portion of time left over from driving and fatigue. She has done the 3D-days in/l4-days out routine, and for approximately the past four years has been existing on a two-weeks in/two-weeks out ritual .The author does not agree that the ""bottom line is that mining families go where the jobs are"" . The miners go where the jobs are and the families fend for themselves with the assistance of the pay cheque making it home each pay period.Perhaps because there are many personal frustrations with this type of lifestyle, perceptions may be inaccurate. Having only dealt with underground operations, there may be gross differences between the pressures and demands of other forms of mining."

Jan 1, 1991

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 J. C. Johnson

Underhand mining with cemented mill tailings for backfill has proven to be a safe and effective alternative to conventional overhand mining for rockburst prone mines. The ability of the cemented sandfill to survive a rockburst shock wave without failing has been observed at mines in the Coeur d?Alene Mining District many times in the last twenty years. To better understand the dynamic loading of this commonly used support material the National Institute for Occupational Safety and Health (NIOSH) performed laboratory experiments using a split Hopkinson Pressure Bar (SHPB) to quantify the maximum stress and energy absorption of cemented mill tailings from the Galena mine. Cylindrically shaped cemented backfill specimens aged 28 days were placed in the split Hopkinson pressure bar testing apparatus and a dynamic load was applied. The measured peak dynamic compressive strength of the cemented sandfill was 10.6 MPa (1540 psi) and is approximately twice the static unconfined compressive strength (UCS) of 5.5 MPa (800 psi). These test data showed about 95% of the initial energy was reflected away from the backfill and only 5% of the energy was absorbed. This may help to explain why backfilled stopes could withstand seismic events up to 3.5 Richter magnitude (Ml). When a compressive rockburst wave impacts a stope a large amount of the stress and energy is reflected away. The reflected wave is a tensile wave which creates tensile cracks and spalling in the entire wall of the stope. The backfill supports the damaged wall rock and holds it in place. Some of the stress and energy of the rockburst is transmitted into the backfill and because the backfill is being dynamically loaded it has a strength that is twice its static value and absorbs a substantial amount of rockburst energy. Although mining in deep underground mines is an extremely hazardous occupation, the use of underhand mining with cemented backfill for static and dynamic ground control increases the safety of the workers.

May 1, 2007

By E. Yan, M. Mankosa, E. Wasmund

"Rougher flotation in sulfide ore applications is typically performed using conventional flotation machines. The trend over the last 100 years has been for these cells to become larger in volume with cells reaching sizes of 600 m3 and in some cases even larger. The associated foundation loadings, transport and installation requirements along with building size have also increased. In an economic environment where projects must be executed with dwindling capital supply, bigger is not always better. More recently, industry is being challenged to identify new technology that allows for improved flowsheets and financial returns through efficiency gains. To meet this challenge, a novel high-intensity two-stage flotation system known as the StackCell™ was tested to potentially achieve installation volume and required retention time gains when compared to conventional flotation circuits. The results from on-site pilot scale work conducted on typical copper concentrator rougher flotation feed showed retention time gains on the order of 6 to 9 times when compared with conventional flotation equipment. This finding has the potential of reducing capital demands for rougher flotation circuit designs when incorporating the StackCell. The results from test work will be discussed in this paper showing comparative test data generated with a Denver bench batch test, pilot StackCell and large conventional cells, all receiving the same feed.INTRODUCTION Over the last few years, a number of flotation devices have been described as two-stage or multi-stage flotation units. The idea behind multi-stage flotation devices is that flotation performance can be improved by utilizing cells with multiple specialized units in series, but not all units of the same type, as is practiced in trains of multiple tank cells or columns. Instead, each unit is specially designed to provide the optimized fluid environment for each stage of the sequential flotation process. This idea has been proposed based on a study of the fundamentals of the flotation process, and the realization that the process consists of discrete sequential processes, that are each optimized with dissimilar process conditions (Finch et al, 1995), (Zhou, 1996). Instead of executing each step simultaneously in a homogeneous fluid environment, where the conditions would be a compromise between particle collection and froth recovery, the multi-stage flotation unit operates in a set of segregated process environments, each with a set of conditions optimized for that step."

Jan 1, 2018

By Nigel Saunders, Zhanli Guo

"Quench sensitivity of heat-treatable aluminium alloys is closely related to the precipitation process taking place during quenching. Faster cooling results in less precipitation of coarse phases during cooling, leaving more solutes in the solution before ageing. An alloy in such state would be of greater hardening potential as larger amounts of hardening phases may precipitate out during ageing. Hence, to understand the quench sensitivity of an alloy, it is essential to understand its precipitation process. Precipitation is a diffusion-controlled process and the diffusion is made complicated by the so-called quenched-in vacancies. These vacancies form during solution treatment, become “excess” when temperature goes down, and annihilate during the following cooling and ageing treatments, making diffusion now a function of both temperature and time. This paper first investigates the formation and annihilation of quenched-in vacancies and their effect on diffusion. The diffusion affected by quenched-in vacancies is considered in the kinetic models to realise the calculation of TTT/CCT diagrams for aluminium alloys. The calculated CCT diagrams have been used to explain the observed quench sensitivity and age hardening behaviour of various commercial alloys. The transformation from GP zones to other hardening phases during ageing is also discussed.INTRODUCTION The heat treatment of aluminium alloys mainly consists of three stages: a solution treatment at an elevated temperature, quenching from this solution treatment temperature to room temperature, followed by an ageing treatment to allow the precipitation of strengthening phases(Davis, 1993).The following statements generally describes how quench sensitivity is observed in heat-treatable Al-alloys: faster cooling results in,(i) less precipitation of coarse phases formed at high temperature during cooling, (ii) more solutes kept in solution before ageing, and (iii) larger amounts of hardening phases being formed, i.e. a greater hardening potential. Thus, the quench sensitivity of an alloy is closely related to its precipitation kinetics."

Jan 1, 2018

By W. L. Single

"LET ME FIRST OF ALL thank you for sending this invitation to me to participate in this Annual Meeting of The Mining Society of Nova Scotia. As an engineer, although I don't get an opportunity to practice very much engineering these days, I am, of course, always pleased to be able to meet with my fellow engineers to exchange views, but I must admit that today I feel a little bit out of place in the midst of all the experts that are here today. Let me make one thing clear - I'm a generalist! Your program states that I am to make a keynote address. I have always thought that a keynote speech is one that says something that has not been said before - announces some new program or policy, or says something startling. I am sure you will understand when I tell you that keynote addresses are made by politicians and that civil servants speaking publicly are usually expected to give an account of what is, or what is likely, to happen as a result of policies that have been announced in keynote speeches by politicians. I am reminded of a statement by a distinguished parliamentarian who said, ""However exalted a civil servant may be, he is not above the elected officials."" So today I will confine myself to giving you an overview with particular emphasis on the development side of oil and gas. The theme of ""Oil and Gas"" is a topical one these days. I suppose it's because of all the copy that is being generated by the media on the U.S. energy crisis, the Mid-East situation, the fact that most of the world's proven oil reserves are in Arab hands and, of course, the accelerated exploration activity that is taking place in the North Sea, in the Arctic, and off the coast of Newfoundland and Nova Scotia."

Jan 1, 1973

By Masahiro Eguchi, Giuseppe Granata, Chiharu Tokoro, Hiroki Fukuda, Yuichiro Toba, Shungo Hobo

"Currently, large amounts of wastewater containing boron are discharged from industries like coal-fired power plants. Although coagulation-sedimentation is widely employed for their treatment, only a little consideration has been given to its mechanism. An additional problem is that the produced sludge has poor solid-liquid separation. This study is focusing on coagulation-sedimentation using magnesium, examining the mechanism and improving the solid-liquid separation. First, the co-precipitation with magnesium hydroxide was conducted against high-concentration boron wastewater with 500 mg/dm3as B. Second, in order to improve the solid-liquid separation by maintaining high reactivity, low-crystalline magnesium oxide was synthesized from magnesium carbonate by calcination at 400–700°C. It was tested as an adsorbent of boron and compared to co-precipitation with magnesium hydroxide. Co-precipitation showed high removal capacity. X-ray diffraction (XRD) of the sludge revealed the presence of other compounds besides magnesium hydroxide. This result suggests that other processes play a role other than simple adsorption on to magnesium hydroxide, and provides a plausible explanation for the observed high separability. As for the adsorption, the synthesized magnesium oxide immobilized as much or more amount of boron than co-precipitation. Furthermore, the results of fourier transform infrared spectroscopy (FT-IR) suggested the residual magnesium carbonate improved solid-liquid separability due to its poor solubility.INTRODUCTIONBoron is used in various industrial applications. In glass industry, the addition of a little amount of boron into glass products can enhance heat-resistance and chemical-resistance. Semi-conductor industry also employs boron as dopant for silicon. From these industries, large amounts of wastewater containing boron have been discharged. Additionally, coal-fired power plants have been recently discharging highly concentrated boron wastewater because the amount of boron contained in coal has been increasing due to a gradual decrease of the quality of coal. Since boron is partially proved to be toxic for animals, plants, and human beings (WHO, 1998),the guideline of the World Health Organization limit the boron concentration in drinking water to 2.4 mg/dm3(WHO, 2009).Because boron does not precipitate from solutions by simply changing the pH, the removal could be carried by operations such as adsorption or ion exchange. However, since ion exchange is an expensive operation with relatively low capacity, it is not suitable to treat the large amounts of wastewater produced by heavy industries like the coal-fired power plants. Therefore, coagulation-sedimentation method is still widely used as a suitable alternative way."

Jan 1, 2017

By H. Son

The three-dimensional (3D) reconstruction of as-built industrial plant models plays an important role in revamping planning, maintenance planning, and preparation for dismantling during the lifecycle of industrial plants. Recently, the 3D reconstruction of existing industrial plants was conducted using laserscan data to make surveying processes more efficient. However, the current 3D reconstruction process from laser-scan data is still limited due to the need for significant human assistance. Although a great deal of effort has been made to efficiently reconstruct 3D as-built industrial plant models, the presence of objects?such as equipment, pipelines, and valves of different sizes and shapes?in existing industrial plants significantly increases the complexity of laser-scan data and makes automating the reconstruction process more challenging in practice. The purpose of this study is to propose a knowledge-based approach for the 3D reconstruction of as-built industrial plant models from unstructured laser-scan data. First, pipelines were extracted from laser-scan data based on surface curvature information and knowledge about pipelines' sizes from existing piping and instrumentation diagrams (P&ID). Once entire pipelines were extracted, they were modeled based on skeleton features. Then, the remaining objects were clustered and grouped separately via the region grouping process. Afterward, clustered objects were retrieved and modeled based on global feature-based matching from the 3D database. Finally, the resulting model was checked to ensure that it was well-reconstructed according to the information regarding the relationships among objects abstracted from the existing P&ID. The preliminary results on actual industrial plants show that integrating knowledge into the reconstruction steps played an important role in the proposed approach and that this approach obtained accurate as-built industrial plant models from unstructured laser-scan data. The proposed approach could be successfully utilized to assist in many applications during the lifecycle of industrial plants.

Aug 1, 2013

By A. Roy MacLean

This paper outlines the changes in modern-day coal mining that have been brought about by the increased cost of labour and the use of new and highly efficient equipment. In the latter category are mentioned the ramp-plate, the Bretby cable carrier, armoured face conveyors and the shearer-loader. Greater productivity and increased safety are emphasized.

Jan 1, 1969

By P. A. Peach, W. H. Gross

The modern economic geologist in Canada is well equipped to apply geological, geochemical or geophysical techniques in the exploration for ore. Recently, great advances have been made in geophysics and geochemistry, and a large number of new orebodies have been discovered by these methods. An attempt is made in this paper to show that there has also been a considerable advancement in geological knowledge and that the most effective application of geophysics and geochemistry often occurs in areas already considered geologically favourable for the occurrence of ore. Ali exploration methods sooner or later suffer from diminishing returns. Therefore, as time goes on, one can expect to see the application of some of the more subtle or refined geological techniques that are presently being developed.

Jan 1, 1967

By John A. Teeter

"A SHORT WHILE AGO I enquired about The Mining Society of Nova Scotia. In all honesty I was apprehensive about addressing such a body if it was highly geared to the technical aspects of discovering and obtaining mineral resources. I was told that this would not be the case. Rather, there would likely be in attendance a broad cross section of people from business, industry and government and from across Canada and the U.S.A. Thus there would be an interest in a free-wheeling discussion of the prospects for industrial development in Cape Breton. Accordingly - being one who hates to miss an opportunity - I intend to exploit the invitation of your executive by being, over the next short while, frankly promotional. I would like to talk about what I consider to be some of the most important attributes of Cape Breton for industrial development and identify some of those prospects. Secondly, I will quickly review some of the things the Cape Breton Development Corporation is doing these days to stimulate some of that industrial development."

Jan 1, 1972

By S. Amid, D. Fisk

"Wireless technologies are permeating the mining and metals industry and enabling a myriad of benefits. With standards such as IEEE 802.11 for wireless devices and ISA100.11a for wireless field instruments protecting their investments, customers look to benefit from the cost and flexibility offered by wireless devices. Using wireless field instruments, plants are eliminating the costs associated with wired system by 50 to 70% and using these savings to install more field instruments, which, when used smartly, enables them to optimize their processes efficiency and equipment reliability. Wireless also empowers a mobile workforce by allowing them to have access to key process and maintenance data directly from the field. This paper describes how wireless can help operations and maintenance personnel to be more effective. Three case studies, illustrating how the mining and metals industry is taking advantage of the technology today, are presented:1.,Optimisation of the water recovery process using wireless2.,Field operations improvement with wireless handhelds3.,Improving fleet maintenance through wireless mobile equipment management"

Jan 1, 2011

By C. R. Ross

"THE ASSESSMENT of pneumoconiosis-producing dusts in mines and other industries is usually undertaken for one or more of three reasons: (1) To compare dust exposures at particular operations with standards of permissible dustiness in order that hazards may be evaluated and preventive procedures initiated where required.(2) To study particular operations with the objective of improving dust control devices or procedures by locating dust sources. (3) To obtain data which, along with the results of medical investigations, may assist in understanding the causes of dust-induced diseases or aid in the establishment of permissible standards of dustiness. Most dust measurements are made for the first of these reasons -to evaluate dust hazards so that they may be controlled. For this purpose, four quite different assessment techniques have been in widespread use for many years. One of these is based on the konimeter, an instrument familiar to most .Canadian mining men; a second on the impinger, which is also widely used in Canada, and almost exclusively so in the United States; a third on the thermal precipitator, used extensively in Britain and South Africa; and a fourth on the tyndallometer, a light-scattering instrument used in Germany."

Jan 1, 1960

By J. S. DeLury

Introduction The problems of metallogenesis are largely related to those concerning the origin of igneous rocks, which, in turn, are involved with the question of crustal mechanics. Many ore-bodies are genetically related to associated intrusive and there is an equally close association apparent between igneous intrusion and crustal deformation. The problem of ore-deposition is concerned, therefore, with the fundamental problems of geology. For a long time speculations regarding crustal movements rested largely on the contraction theory and its associated conceptions. Vertical movements were considered to be all important and horizontal movements secondary to them. Magmas were pictured as rising more or less vertically in the crust and were believed to form in vertically disposed magma-chambers or reservoirs. The principle of magmatic differentiation seemed to offer the best explanation of the origin and association of diverse rock types and it seemed also to require the existence of quiescent magma-chambers for the admittedly slow process of differentiation. Accumulating evidence of the importance of horizontal movement in the crust, has, along with other considerations, discredited the contraction hypothesis and many of the inferences that go with it. The same evidence may require some change in the prevailing conception of the origin of the various types of igneous rock and of the mechanics of intrusion. Geologists are now at sea concerning some of the vital and fundamental problems of the crust, and the field is open for speculation. The writer is developing a hypothesis which seems to permit an explanation and? a correlation of earth structures and phenomena. If it rests on a firm foundation, the hypothesis, because it is fundamental, is certain to have a profound bearing on the problems of economic geology. It is for this reason that an outline of the hypothesis is offered at this time. Only a few of its economic bearings are foreseen at this time and these will be indicated.

Jan 1, 1932

By A. Taylor, E. Thorn Corthay, J. Farrell, L. A. Westfall, S. Borchardt

Mining and metallurgical industries need to minimize their greenhouse gas (GHG) emissions; Hatch specializes in conducting mining and metallurgical energy management assessments and optimizing productivity. Projects executed have demonstrated that there is a wealth of energy management, waste reduction, and process efficiency improvements that require no or low capital investment. Typical energy cost savings are on the order of 5% to 12%, with similar reductions in GHG emissions. Hatch generates Marginal Abatement Cost Curves to optimize the implementation pathway, maximizing carbon abatement and minimizing cost. The findings of a practical case study from Cameco are presented.

Jan 1, 2010

By R. L. Bishops

This paper discusses some of the materials, processes and systems used in motor insulation. Among the materials mentioned are epoxies, polyesters, mica paper composites and wire enamels. Two processes developed to take advantage of the special characteristics of two of these materials are described, and how these materials are used in several new insulation systems now on the market is discussed. Finally, future trends in motor insulation are outlined.

Jan 1, 1969

"Energy efficiency in mining and minerals processing has attracted considerable public and industry attention because of the significant quantities of energy consumption involved. In this context the question of what are worthwhile targets for energy efficiency improvements ought to be of the highest priority. It is however worth taking a step back to avoid falling in the trap of taking preconceived ideas that have been reiterated repeatedly before as gospel. The aim of this paper is to highlight areas where new or alternative approaches could potentially be the better way forward. Some may come as a surprise to conventional industry thinking. Ultimately any such solutions are attractive to practitioners not just in an environmental but also in an economic sense, and hence should be targeted through applied research and development efforts. This paper highlights key aspects of each group of opportunities and some of the individual approaches to provide an overview of the current status quo.MINING INDUSTRY POWER UTILISATION – WHERE IS THE BIGGEST BANG FOR THE BUCK?The question of where is the biggest bang for the buck when trying to determine worthwhile targets for energy efficiency improvements has not always been reported on broadly enough, typically because industry practitioners operate in specific areas of expertise and comfort zone. Looking beyond the familiar doesn’t always come easy. Any technology or methodology consideration to address energy efficiency needs to take into account the context of alternative opportunities of superior value or risks not achieving desired uptake. The following sub-chapters have been ordered by magnitude of improvement potential as best as is possible, starting with the biggest first, and the smallest last. Some may be a surprise relative to conventional mining industry thinking."

Jan 1, 2016