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By Alfred Traverse

The Brandon lignite is a small deposit of very low rank coal near the village of Forestdale in the town of Brandon, Vt. It occurs in association with other sediments, principally sands and silts. This lignitic coal has attracted considerable scientific interest since the middle of the 19th century because of the abundance of fossils in the sediment and the rarity of lignite in New England. A cooperative investigation has been developed by E. S. Barghoorn, W. Spackman, and the author in which different phases of the problem have been worked on in a coordinated research program. This paper presents results of an investigation of the very abundant fossil pollen and spores and some other microfossils of the deposit. The studies on which this manuscript is based were made in large part at Harvard University in partial fulfillment of the requirements for a Ph. D. degree.

Jan 1, 1955

By Willemijn Husslage

Tata Steel Group At a glance ? Part of the Tata Group ?Tata Steel Group: ?Fortune 500 company ?Top 10 global steel producer ?Annual crude steel capacity of 28 million tonnes ?More than 80,000 employees ?Manufacturing operations in 26 countries across 5 continents ?Serving customers all across the globe ?Turnover 2009-10: $22.8 billion

May 1, 2011

By Ihor A. Kunasz

Lithium minerals occur predominantly in pegmatites that contain mineral assemblages derived from the crystallization of post- magmatic fluids or from the metasomatic action of residual peg- matitic fluids. They have been the traditional sources of raw material for ceramic and chemical industries. With the discovery of the Searles Lake deposits, brines became new sources of lithium, and, today, two brine deposits satisfy nearly one-half of the free world demand for lithium chemicals. Indeed, lithium production from pegmatites has been superseded by brines sources. In the United States, the brines of Clayton Valley, NV, have been exploited since 1964 by Cyprus Foote Mineral Company, a subsidiary of Cyprus Minerals Company. In Chile, Sociedad Chilena de Litio Ltda., an affiliate of Cyprus Minerals Company, is now producing lithium carbonate from the brines of the Salar de Atacama. Recently identified brine deposits suggest that these may well become the prime sources of lithium chemicals. In Bolivia, the government is negotiating the rights to exploit the brines of the Salar de Uyuni. The Salar del Hombre Muerto in Argentina is being evaluated as a future center of chemical production. The brines of the Great Salt Lake of Utah, the Smackover Formation, and the Imperial Valley geothermal field have been defined as important resources of lithium. In Tibet, high concentrations of lithium have been reported in several saline lakes. In the People's Republic of China, lithium may be produced from the brines of the Dabusan playa in the Qinghai Basin. The 1950s saw a great number of lithium companies develop. However, following the termination of the Atomic Energy Commission purchase program in 1959, several companies, such as Maywood Chemical Co., American Lithium Chemicals, and Quebec Lithium Corp., were forced to close their operations. Nevertheless, with the development of new applications in glass ceramics, air conditioning systems, synthetic rubber, and metallurgy (aluminumpotlines), the lithium industry grew steadily. With the potential application of lithium metal in batteries, nuclear reactors, and fuel cells, a steady growth can be foreseen. New products and new applications are likely to stimulate exploration for expanded reserves as well as the search for new sources from which lithium could be extracted economically. Presently identified reserves and production capacity are sufficient to satisfy the conventional market growth of lithium.

Jan 1, 1994

By Joey Hoang, Robert Johansson, Tapani Keronen, Mikael Jåfs, Jani Jansson, Mikko Korpi

At the Copper 2016 conference in Kobe, Japan, Outotec introduced a vision for the year 2020, wherein smelting would make use of four digital cornerstones: intelligent instruments, advanced process control, improved information management and transparency of and access to data. Since then, this vision coined the phrase “Fully Automated Smelter” with the mission promising a concept where no manual actions from human operators would be needed during normal smelter operations. Replacing repetitive physical work, collection and analysis of everyday production data has a great potential for further automation and will provide productive ways to improve efficiency and safety of smelters in the future. Therefore, a lot of emphasis has been put into developing solutions to automate these tasks and to move people out of harm’s way. A lot of new equipment, systems and optimization tools are under development. In addition, a lot of effort is going into developing dynamic process models and advanced control systems to interface with the plant automation systems. The goal is to integrate all these concepts to meet Outotec’s Fully Automated Smelter vision. This paper will cover these latest achievements toward this vision and introduce the near-future of digital smelting. INTRODUCTION As is well known already, the humankind is currently experiencing a change, extent of which is broadly studied by the governmental, educational and industrial institutions and parties. The wellbeing and quality of life have traditionally been improved alongside the developments in industrial production, which is now about to enter its fourth revolution. Therefore, the current change is often described as fourth industrial revolution, or industry 4.0 (or industrie 4.0, as named by Acatech, 2013) and can be considered anything from small incremental development to a ground-breaking global reset that will affect everyone’s lives. Many seem to agree, that the scale of change will indeed be big, even significantly bigger than the three industrial revolutions before it (Pellini, Weyrauch, Malho & Carden, 2019; Geissbauer, Vedso & Schrauf, 2016; Jansson, Bjorklund, Lahtinen, Heinonen, Jafs & Fagerlund, 2016).

Jan 1, 2019

By M. W. Hildyard, M. O. Kataka

Seismic integration schemes aim to incorporate the rock mass response provided by the historical seismic activity to improve the ability of numerical models to reproduce future response to mining. Up to now, integration schemes considered the events using quasi-static models. This paper presents case studies that consider some of the seismic and modelling issues needed to extend these schemes to include the dynamic characteristics of seismic events. The ultimate aim of an automated integration scheme seems impractical for dynamic modelling. The predictions of the WAVE elastodynamic finite difference program are, however, suitable for modelling limited numbers of events to determine either the near-field velocities and damage or the effect of fractures and excavations on the far-field low frequency response. Les projets d’intégration sismique ont le but d’incorporer la réponse de la masse rocheuse à l’activité sismique historique pour améliorer la capacité des modèles numériques à reproduire la réponse future à l’exploitation minière. Jusqu’à présent, les projets d’intégration étudiaient les évènements avec des modèles quasi-statiques. L’étude présente révèle des études de cas qui considèrent certaines des questions concernant modelage et séismes qui sont nécessaires pour porter plus loin ces projets en incluant les caractéristiques dynamiques des évènements sismiques. Le but final d’un projet d’intégration automatisé semble impraticable pour la modélisation dynamique. En revanche, les prédictions du programme élastodynamique par la méthode des différences finies WAVE sont appropriées à la modélisation d’un nombre limité d’évènements de façon à déterminer soit les vitesses à petite échelle et les dommages, soit les effets des fractures et excavations sur la réponse de basse fréquence à grande échelle. Seismische Integrationsschemata zielen darauf ab, Reaktionen der Gesteinsmasse, die von den Berichten seismischer Aktivitäten stammt, zu inkorporieren um numerische Modelle in die Lage zu versetzen, künftige Antwort zum Bergbau zu reproduzieren. Bis dato betrachteten Integrationsschemata die Fälle mit quasi-statischen Modellen. Diese Arbeit stellt Fallstudien dar, die einige der seismischen und modellierenden Fragen betrachten, die benötigt werden, um diese Schemata auszuweiten, um die dynamischen Charakeristika seismischer Fälle einzuschließen. Das Endziel eines automatisierten Integrationschemas erscheint für das dynamisches Berechnen undurchführbar. Die Vorhersagen des WAVE elastodynamisch begrenzten Unterschiedprogramms sind jedoch verwendbar für das Berechnen von begrenzten Anzahlen von Fällen, um entweder die Nahfeldgeschwindigkeiten und Schaden oder den Effekt von Brüchen und Extraktionen auf der Fernfeld Niederfrequenzantwort festzustellen.

Jan 1, 2003

By Juan Camus

To understand why some companies excel in creating value, Jim Collins (2001) and a group of postgraduate business students engaged in a comprehensive, five-year research project. They examined 1,435 U.S. companies for more than 40 years, seeking those that made significant improvements in their financial performance over time. The distinctive pattern sought was: ?Fifteen-year cumulative stock returns at or below the general stock market, punctuated by a transition point, then cumulative returns at least three times the market over the next 15 years. ?The search identified 11 outperforming companies, all in different industries, that were called the ?good to great? companies. To contrast these companies with similar peers within the same industry, the search also selected a group of comparison companies that failed to make the leap from good to great. Collins then set out to examine the transition point. What distinguishing features did the good-to-great companies have that their industry counterparts did not? At the heart of the findings about these outstanding companies is what Collins refers to as the ?hedgehog concept? ? how to find the one big thing that the company must focus on. According to Collins, those who built the good-to-great companies were, to one degree or another, hedgehogs. Those who led the comparison companies tended to be foxes, never gaining the clarifying advantage of a hedgehog concept, being instead scattered, diffused and inconsistent. This insight is complemented by Peter Drucker (2004), an influential management guru, who asserts that the first question an effective executive should ask is: ?what needs to be done?? Asking this question and taking it seriously, he asserts, is crucial for managerial success; and that the answer almost always has more than one urgent task, but the effective leader only concentrates on one task. In this last respect, Drucker emphasizes: ?If they [executives] are among the sizeable minority who work best with a change of pace in the working day, they pick two tasks. I have never encountered an executive who is effective while tackling more than two tasks at a time.?

Jan 1, 2011

By Katherine A. Klein

Refuge chambers may potentially save the lives of miners during a mine emergency. For this reason, it is crucial that miners know how to operate them. Unfortunately, because refuge chambers provide so many services, they can be very complicated and difficult to operate. Therefore, NIOSH has created this document with suggestions for developing manuals and educational materials. A multidisciplinary team comprised of NIOSH engineers, sociologists, psychologists, health communication professionals, and geologists developed the recommendations contained in this document. These recommendations are based on an evaluation of manufacturers? instruction manuals from both the U.S. and globally, interviews with over 20 mining and safety experts, and an extensive literature review. This research, focused on the best practices for refuge chambers, led to the formulation of this document. It is intended to offer suggestions to manufacturers and mine operators on how to create effective and easy-to-understand training manuals for miners as well as tips to create the most comfortable and usable refuge chambers. It should be noted that these recommendations are not meant to substitute for manufacturer-supplied materials but rather to be used in conjunction with manufacturer?s materials. Manufacturers should always be consulted for up-to-date information about their chamber. Although different states and different mines refer to underground refuges by different names, this guide will simply refer to underground refuges nearest to the face as refuge chambers, whether inflatable from a skid or constructed from steel. Other popular terms for refuge chambers are rescue chambers, rescue shelters, and refuge shelters. Refuges that are nearer to the shaft, whether a prefabricated refuge chamber or one built into a crosscut, will be referred to as outby refuges because of their location in the mine. Outby refuges can be permanent, semipermanent, or portable and are usually located at every other SCSR cache. Outby refuges are sometimes called hardened rooms, outby shelters, and in-place shelters. When discussing outby refuges and refuge chambers collectively, this guide will refer to them as underground refuges. Other terms for underground refuges include refuge alternatives, locations of safety, and safe havens. This document is designed to be read either cover to cover or by specific section. It is recommended that on first read, this guide be read cover to cover. In subsequent readings, manufacturers and mine operators may find it easier to use the table of contents page to locate specific information on parts of the refuge chamber.

Jan 1, 2009

By Earl T. Hayes

THIS BIBLIOGRAPHY has been assembled to aid research by the Bureau of Mines, and others on high-purity tungsten. It appears approximately 50 years after the development of ductile tungsten-one of the first metals to be produced in a high-purity form. Requirements of the missile age are ever more demanding that engines rout hotter and space vehicles fly higher and faster. Thus, it has become necessary to reexamine all conventional materials of construction as well as to investigate new combinations. At this stage of our technology we have alloys capable of operation at 1,800° F. and several possibilities of developing some. that will be satisfactory up to 2,500° F. Strength-weight comparisons, detrimental to tungsten at, lower temperatures, disappear at this point, mid tungsten or its alloys appear to be the only metal capable of operation at truly high temperatures. The aim of this bibliography has been to include only references that concern improving the purity of tungsten-from processing the ore to treating the finished metal. In this sense it is a selected and not a critical bibliography. The period front January 1911 through February 1959 has been covered. Because repent literature has the greatest, value, most of the selected items refer to publications issued within the pest 5 years.

Jan 1, 1960

By R. B. Bauder

In connection with a Bureau of Mines research program on utilization of Cuban lateritic ores, a comprehensive review was made of the chemical literature on nickel and cobalt. Initially, the review had as its objective the selection, from the voluminous literature dealing with the chemistry of these two metals, of only those references to reactions that were especially pertinent, or at least closely related, to the field of extractive metallurgy. Later, the coverage was extended to include references to the techniques and plant applications of extractive metallurgical procedures for the recovery of nickel and cobalt. In this report, the period from January 1929 to July 1955 has been covered, as it seemed logical that recent literature should be of greatest value. This cutoff date was established in order that the bibiliography could be issued at an early date, inasmuch as currently much work is in progress on the lateritic ores. Later, a supplement will be prepared extending the coverage to about 1900.

Jan 1, 1957

By H Möller

The purpose of this paper is to give an overview of the corrosion behaviour of steel in seawater. It is shown that the corrosion products (oxy-hydroxides and calcareous deposits) that are formed during corrosion in seawater have a significant effect on the corrosion behaviour of steel. The chemical composition of the steel determines how protective the oxy-hydroxide corrosion product is. The composition of the seawater influences the nature of the calcareous deposits. This needs to be considered when artificial solutions are used to simulate the corrosion behaviour of steel in seawater. A 3.5% NaCl solution is used frequently for this purpose, but because no calcareous deposits can be formed in this solution, erroneous results in terms of corrosion rates are obtained. The more complex ASTM D1141 artificial solution can be used to include the effects of ions other than Na+ and Cl- in synthetic seawaters. The importance of these other ions on the formation of calcareous deposits is discussed. Keywords: Steel, corrosion, seawater, calcareous deposits, oxy-hydroxides

Jan 1, 2006

By J. M. Benson

Metal powder compaction offers unique advantages in the manufacture of net-shape components using techniques such as laser sintering, conventional press and sintering, metal injection moulding, direct rolling, direct forging, and hot isostatic pressing. If the output from the primary metal production process is in powder form, then considerable cost and energy savings can be realized by direct conversion to semi-finished or final shapes. This possibility exists for titanium and possibly also for Ta, Zr, Hf, and Nb metals. However, these attractive benefits are associated with some significant risks. The high surface-to-volume ratio of powder particles coupled with the reactive nature of these metals means that special care must be taken when handling them. Powder explosions are unfortunately still a regular occurrence internationally and these often result in serious injury and loss of life. Even seemingly 'safe' compounds such as sugar, flour, and grain can be extremely hazardous when handled or milled and dust clouds are produced. In addition, exposure to airborne particles can have adverse effects on the human body, especially when particles are inhaled on a regular basis. Furthermore, the medical consequences of these are not fully understood, especially in the case of nanoparticles. The impact is often not observed immediately and debilitating illnesses may emerge only years or decades later. As far as is known, there are no South African guidelines for handling of metal powders. This paper attempts to provide an awareness of the risks associated with metal powders (including those produced indirectly by other metalworking/finishing operations) as well as some guidelines for their safe handling, based on international best practices.

Jan 1, 2012

Australian coals tend to be young in geological age and high in ash by world standards; preparation of the coal before marketing is almost universal. On the basis of float and sink data from 39 locations in the Eastern Australian coalfields, the coals are placed in four categories representing increasing difliculty in their washability characteristics. These seem to be related neither to the geological age nor the geographical position of the deposit and Hunter Valley coals, for example, span all categories. The influence of crushing on the washability of Australian coals is briefly considered and from limited data it is concluded to be appreciably smaller than for British or North American coals. A strategy for the float and sink analysis of Australian coals is proposed and the influence of washability characteristics on current trends in the selection of separating processes for coking and steaming products is discussed.

Jan 1, 1979

By Warren E. Morrison

The first major evaluation of the nation's raw materials prospects after World War II was completed by the President's Materials Policy Commission (Paley Commission) in 1952 and submitted to the President in June of that year, as a five-volume study entitled Resources for Freedom. The bulk of the report was devoted to an analysis of the past, present, and probable future of the Nation's mineral supply industries. The Commission's evaluation of the future situation regarding minerals was derived from its forecasts of the probable domestic demand for the major minerals in the 1970's. This demand analysis was made in the context of probable worldwide demand. Several crucial assumptions were made by the Commission's fore-casters. It was assumed in 1950 that the next 20 to 30 years would see no major wars and be a period of sustained economic growth. Another assumption was that the anticipated demand for raw materials must be supplied at essentially no increase in real cost in order to avoid crucial supply problems. The Commission's forecasts were derived within the context of the country's expected future rate of economic activity. The gross national product (GNP) growth to 1975 was derived from projections of the number of people in the labor force, hours of work, and an index of probable production measured per unit of labor input. It was believed labor hours would decrease and labor productivity would increase. The result was a forecast GNP growth rate of 3 percent.

Jan 1, 1970

By Wendell L. Reich

Percussion drilling dates back to the hand operated star drill and hammer. Eventually steam and compressed air were substituted for muscle power and the mechanical percussion drill was born. From the hand held jack hammers, driving a forged steel bit into the rock, there evolved the jack leg, the rubber tired and crawler mounted drill carrier with automatic feed, increasing power and reducing man?s muscle requirements. Because the reaction of a blow on one end of a piece of steel has to be transmitted to the other end there is a limit to the depth or length of drill steel that can economically be used in out of the hole percussion devices. During the late 1800?s there is evidence that designers were attempting to put the percussion tool at the bottom of the hole, directly on the bit, in order to avoid the long drill steel which absorbed much of the blow, leaving little to be applied to the bit and the rock being drilled.

Jan 1, 1972

By G. S. Scott

Safety problems in the mining and allied industries have led the Bureau of Mines to investigate over a period of years; the flammability (explosibility) of many types of combustible atmospheres principally at ordinary pressure; the results of these investigations have been made available as a bulletin. However, more recently, the demand for information on the flammability of gaseous mixtures at high and low pressures has increased greatly. In particular, the rapid development of high-altitude aviation has brought demands for information on the flammable (or explosive) characteristics of certain gases and liquids at low pressures. The present report gives the results of about 900 tests made to determine the flammability of the lighter paraffin hydrocarbons mixed with air and nitrogen at pressures of 400 200, 100 and 70 ram. Hg. The gases tested include natural gas, methane, ethane, propane normal butane and isobutane. The minimum pressures at which these gases are capable of propagating flame whorl individually mixed with air also were investigated.

Jan 1, 1952

By A. Berry, N. R. Banerjee, C. S. Finnigan, M. Fayek, N. J. Bridge

Lac Cinquante is a mineralogically simple, vein-hosted uranium deposit in Archean basement rocks (Angikuni greenstone belt) that originally were unconformably overlain by Proterozoic sedimentary and volcanic rocks of the Baker Lake Group (BLG). Basement rocks are mainly pillowed and massive tholeiitic lavas (N-MORB) with interbedded tuff; overlying sedimentary rocks comprise a basal talus/fault breccia that grades upward into fluvial sedimentary rocks and subaerial, trachytic volcanic rocks; granite and porphyry dikes (Hudson and/or Nueltin granitoids) intrude the basement rocks. A typical section through the Main Zone comprises 1) laminated ‘tuff’, 2) altered (carbonate-hematite-chlorite) schistose ‘tuff’, 3) a pitchblende-bearing, breccia-vein, 4) altered ‘tuff’, and 5) laminated ‘tuff’. The vein comprises brecciated chlorite, hematite, and pitchblende with carbonate cementing the breccia. Graphitic ‘tuff’ with sulfide-stringer veinlets locally overlies or underlies the vein. Pitchblende also occurs in the altered rocks and in gash veins that cut basement rocks. U-Pb ages on pitchblende fall into two groups: one at 1828 } 29 Ma reflects primary uranium mineralization, and a second at 1437 } 31 Ma represents resetting. Pb-Pb chemical ages show other resetting events at 1260-1321Ma, 895 Ma, 741-813 Ma, and 660-706 Ma. One possible genetic model for the Lac Cinquante deposit involves leaching of uranium from granitoids and the BLG by basinal brines that migrated to depositional sites where graphitic rocks acted as a reductant. A second model requires that uranium was sole-sourced from the BLG and that granitoid rocks provided heat to drive the hydrothermal system, which leached and ultimately precipitated uranium. The deposit has characteristics similar to vein-type uranium deposits in the Beaverlodge District of Saskatchewan

Jan 1, 2013

By Enzo Palumbo, Joël P. T. Kapusta, François Larouche

In light of the rapid deployment of bottom blowing smelting in China over the last ten years, one has to wonder why it has taken the copper industry so long to adopt ultra-high oxygen enrichment via Savard-Lee type injectors. As early as 1976, Kellogg and Henderson suggested, in their landmark paper on energy usage in the copper industry, that ‘maximum use of oxygen enrichment of process air’ was one of seven ‘energy saving features’ for copper matte smelting and converting. Yet today, shrouded injection and high oxygen enrichment has not been implemented in copper bath smelting outside China and Vietnam. In this paper, the authors explore the reasons why bath smelting processes such as the Noranda Reactor and the Teniente Converter still operate around 40% oxygen enrichment, while the bottom blowing SKS/BBS process typically runs at 65 to 75% oxygen, with all three processes producing white metal. Are there fundamental metallurgical explanations for this striking difference beyond the long-standing skepticism towards high oxygen shrouded injection and its perceived high implementation cost?

Jan 1, 2015

By Clarence Karr

AN EXTENSIVE characterization was conducted on the neutral oil components in a low-temperature bituminous coal tar. A total of tai individual compounds identified with respect to individual isomers, and at least 55 other compounds were indicated to be present. The amounts were determined in all instances. A comparison of isomeric distribution in the tar with thermo-dynamic equilibrium distribution, and kinetic distributions indicated that the composition of the tar largely reflected the structure of the coal from which it was formed. Detailed descriptions are presented for the separatory and qualitative and quantitative procedures for the characterization of the neutral oil component. These include micro fractional vacuum distillation, displacement liquid chromatography, gas-liquid chromatography, countercurrent distribution, and infrared and ultraviolet spectrophotometry. Descriptions are given for the synthesis of authentic specimens of alkylindenes, The ultraviolet and infrared spectra of 134 polycyclic compounds, ranging from alkylindenes to alkylphenanthrenes, either found in the distillable neutral oil, or thought likely to be present, are also given.

Jan 1, 1967

By Victor Romero, Steve Redmond

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of individual authors and are not necessarily those of the SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2011

By H. Foster Bain

I. INTRODUCTION. By H. FOSTER BAIN.+ THE recently aroused public interest in the conservation of our natural resources has peculiar importance to mining-men, since they deal with resources which are stored products. Within certain limits, the fertility of a worn-out soil may be restored, deforested areas can be replanted, one year's wasted water-supply is followed by another; but coal and ores, once taken out, cannot be mined again, and should therefore be conserved with especial care. This means, however, not that mining should be restricted, but that it should be done most economically and with the minimum of waste.

Nov 1, 1908