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By Thierry Bernard, Pierre M. Vuillaume, Michel Kiszlo

"In the context of its studies for the trench ministry of the environment and for the French national coal board, INERIS (the French institute for the industrial environment and hazards, formerly CERCHAR) has made a complete critical survey of the methods generally used to reduce the levels of blastingvibrations."

Jan 1, 1996

By M. Tamlin

The state of the lithium mineral industry is closely linked to the performance of the glass and ceramic industries and to the overall economy. Demand for the glass/ceramic products in Europe, Asia and North America remained strong during 1999. This was due to a slight improvement in the economy during the latter half of the year. Consequently, demand for lithium minerals was firm, with a positive outlook. The major economic minerals for lithium are spodumene, petalite and lepidolite. The latter was once the primary mineral. But its importance hasdeclined since the 1960s. The lithium industry consists of two different segments: •The lithium minerals segment mines from hard-rock deposits and physically processes the material to high-grade concentrates. •The lithium chemicals and metal industry segment. The major feedstock for specialty lithium chemicals was previously high-grade spodumene ore converted to lithium carbonate. However, most lithium carbonate is now sourced from salars in North and South America.

Jan 1, 2000

By D Cumming-Potvin, S W. Jacobsz and E Kearsley, J Wesseloo

This paper describes a physical modelling program that recreated block cave propagation in a geotechnical centrifuge. A brief description of the design of the test along with the sample material and monitoring equipment is given. The samples tested showed caving behaviour and fragmentation distributions that one would expect from caving mines, with one cave deviating due to pre-existing major discontinuities in the sample. A series of fractures formed ahead of and parallel to the cave, implying that an extensional failure mechanism may play a larger role in cave development than previously thought. The results of acoustic emission monitoring of the tests show a seismogenic zone advancing ahead of the cave; however, the quantity and quality of the data is too limited to draw any further conclusions.CITATION:Cumming-Potvin, D, Wesseloo, J, Jacobsz, S W and Kearsley, E, 2016. Results from physical models of block caving, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 329–340 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By James W. Martin

This user's manual analyzes the application, selection and performance of front-end loaders in mining operations which can effectively utilize their load-and-carry capability. All aspects of the application are considered starting with a discussion of the load-and-carry system and alternate material handling methods. Site conditions such as the geology of the formation, material characterisitics, alternative mine plans and working conditions are identified. Selection considerations include machine design characteristics, production capabilities and ownership and operating costs. Typical operating practices and safety procedures are discussed. Comprehensive machine specifications, together with a series of checklists and worksheets, are included for preliminary analysis.

Jan 1, 1981

By J. J. S. Sebastian

The process development described in this report was carried out at the Morgantown Station of the U. S. Bureau of Mines in cooperation with West Virginia University. An experimental laboratory-scale pilot unit to gasify coal dust in entrainment was constructed on the Campus of the University in Morgantown. The enormously accelerated demand for liquid and gaseous fuels and utilization of our immense coal resources require that a low-cost process be developed for the gasification of a wide variety of coals. Such a process would be a major factor in lowering the cost of synthetic liquid fuels. None of the proc3sses developed in Germany prior to and during World War II, such as the Winkler process, the H. Koppers dust gasification process, the Wintershall-Schmalfoldt process, etc., meet all the requirements for a low-cost process under American conditions. Nor has any other process designed and experimentally operated at atmospheric pressure during the post-war period in this country appeared to fulfill all of the necessary conditions for a low-cost process.

Jan 1, 1950

A well known rock mass classification system has been altered slightly to address the issues found under remnant mining conditions. By detail study of the expected fracture patterns and local geology, the rock mass is classified to indicate the condition of the hanging wall prior to mining. The risk level of each mining step is evaluated by calculating input parameters for computer simulations from the actual rock mass condition. Seismic activity is catered for by the understanding that large event rates and large magnitude events reduce the quality of the local rock mass and that the rock mass stiffness should be adapted accordingly. A case study is presented to test parts of the protocol. Un système connu de classification des masses rocheuses a été légèrement modifié pour faire face aux questions posées par les conditions d’extraction de débris. Une étude détaillée des diagrammes de fragmentation et de la géologie locale permet de classer la masse rocheuse pour indiquer la condition du toit avant l’extraction. Le niveau de risque de chaque étape minière est évalué en calculant les paramètres d’entrée pour simulation par ordinateur à partir de la condition réelle de la masse rocheuse. L’activité sismique est prise en compte avec la réalisation que les taux de larges évènements et les évènements de large magnitude réduisent la qualité de la masse rocheuse locale et que la raideur de la masse rocheuse doit donc être adaptée. Une étude de cas est présentée pour tester des sections du protocole. Ein sehr bekanntes Gesteinsmassenklassifikationssystem wurde abgeändert um die Probleme zu behandeln die unter Restabbaukonditionen angetroffen werden. Durch detaillierstes Studium der der zu erwartenden Bruchmuster und der lokalen geologischen Verhältnisse wird die Gesteinsmasse in Hinblick auf die Konditionen der Flözoberseite klassifiziert. Das Risikoniveau für jeden Abbauschritt wird durch die Eingabeparameter aktuellen Gesteinsmassenkondition für die Computersimulation evaluiert. Für die Seismische Aktivitäten wird Sorge getragen durch das Verständnis, daß große Ereignisraten und Ereignisse hoher Größenklassen die Qualität der lokalen Gesteinsmasse reduzieren und daß die Gesteinsmassensteifheit entsprechend adaptiert werden sollte. Eine Fallstudie um Teile des Protokolls zu testen wird präsentiert.

Jan 1, 2003

By S. Solar, G. Tiess, K. Nielsen, H. Wagner

The paper summarises the results of a recent study of minerals planning policies of the Member States of the EU. The study has shown that contrary to the public opinion the production of industrial minerals and construction minerals is significant the former accounting for about 20 percent of global production, the latter amounting to about 3 billion tonnes per annum. In contrast the importance of metal ores has diminished although metal production in some European countries can still be significant. The study revealed that very few Member States have clearly defined mineral policies. Common to most mineral policies is the emphasis on reducing minerals consumption and recycling whereas the important aspect protecting access to minerals resources is not adequately addressed by most policies. Access to mineral deposits is regulated in most Member States by land use legislation and administration. Information on mineral deposits in land use planning data bases tends to be scarce. This together with the absence of formal mineral policies places minerals at a disadvantage in land use decision making. The emergence in the recent past of environmental legislation and in particular environmental impact assessments has had a crucial effect on the duration of the authorization process for new mineral projects. Examples are given how minerals planning is handled in some of the Member States.

Jan 1, 2005

By W. P. Huleatt, Jr. Traver, Jr. Hazen

"Vanadium and uranium occur widely distributed throughout western Colorado and eastern Utah, and a few deposits have been found in northeastern Arizona and northwestern. New Mexico. The area in which it occurs includes approximately 10,000 square miles and is generally referred to as the vanadium region of Colorado and Utah.The majority of the deposits consist of replacement bodies and impregnations of rare minerals in the lower Morrison formation of Jurassic age. The ore bodies are flat, with irregular margins, and most of them conform to the stratification.The ""rim rock"" topography of the region includes many steep-walled canyons and plateaus, which afford an abundance of outcrops that have been responsible for most of the discoveries of mineralized areas. Delimitation of ore bodies within the areas is accomplished most effectively by core drilling from the surface.The deposits were discovered in 1899 and from 1911 to 1923 wore worked extensively for radioactive uranium ores, principally carnotite.The discovery and marketing of the richer and more cheaply mined pitch-blende ores of the Belgian Congo left the Colorado-Utah deposits without economic importance as sources of radium and uranium, and the region became inactive in 1923. After a period of comparative inactivity, the rising demand of the alloy-steel industry for vanadium renewed interest in the deposits, which were known to contain that metal. By 1938, vanadium production in the area had achieved respectable proportions, and new impetus was given to it by the United States’ entry into World War II in December 1941. In 1942, new treatment plants for vanadium ores were completed in Monticello, Utah, and Durango, Colo. In order to meet the requirements of these and other plants in the region, it became necessary to open new vanadium mines and prepare old onus for production.In an effort to stimulate mining, the Metals Reserve Company initiated a stock-piling program and appointed the united states Vanadium Corporation, to act as its purchasing agent.The extra production was expected to come largely from small, independent operators whose limited funds did not permit them to maintain development and exploratory programs. Study of conditions made it apparent that extensive exploration would be necessary to sustain production, and accordingly the Bureau of Mines initiated an exploratory drilling project on a cooperative basis with the Geological Survey. The principal objects of the work were to enlarge the known ore reserves of the area and, if possible, discover new ones. The results have been gratifying in both respects."

Sep 1, 1946

By L. L. Hirst

In 1944, the 78th congress of the United States enacted Public Law 290, which directed the Secretary of the Interior, acting through the Bureau of Mines, to furnish industry with basic information and cost data for the development of a synthetic liquid fuels industry. Recently published information with respect to the cost of synthetic liquid fuels processes indicates a wide variation in estimated results. To clarify the results and inconsistencies for the hydrogenation of coal, the Bureau of Mines has prepared preliminary designs and calculated detailed investment costs from which the operating costs to produce 30,000 barrels per day of liquid products, mainly gasoline, by coal hydrogenation were obtained.

Jan 1, 1949

By L. L. Hirst

Liquid fuel oils possess certain advantages over solid fuels. Ease in handling, precision temperature control, and almost complete freedom from ash are among those considered when a liquid fuel is selected for use in industrial processing. In some instances these fuels are desirable because more heating units can e packed in a Given space where space is limited, as on snips. In other cases the' are chosen because of lower actual cost per British thermal unit absorbed, or for control of the flame to increase the capacity of furnaces, as in steel and refining.

Jan 1, 1948

By A. K. Mukherjee

The roles of pulsating mechanisms such as the amplitude and frequency of the jig cycle are well established in jigging. Also well established are the roles of the size ratio and the volume fraction of the feed. In iron ore beneficiation plants, these process parameters are optimized to achieve the highest efficiency. However, the role of one of the more important feed characteristics, the liberation characteristic of the feed, has not been studied in detail. Evaluation of the liberation characteristics is difficult because the required washability test is not viable for iron ore feed. In this paper, a new method is proposed in which the liberation characteristics are measured through a separation efficiency value. In the new evaluation method, jigging parameters such as amplitude and frequency of the jig cycle are optimized from the fundamental understanding of the process dynamics and feed characteristics such as size distribution. Then, feeds with different liberation characteristics are tested to evaluate the liberation characteristics of feed in jigging.

Jan 1, 2008

By Thomas Gales

Longwall mining has a high potential for producing bulk production from a single face. Production is interrupted for a considerable time when it is necessary to move the equipment to a new block of coal. The frequency of such moves can be reduced by increasing the dimension of the block to be moved. Merely doubling the tonnage in a block to be mined may increase production by more than 21,000 tons per year. The time taken to move the equipment can be reduced by careful preplanning, industrial engineering analysis, and specially designed equipment. Reducing its move time from 30 days to five days can increase production by more than 25,000 tons per year. Increasing the panel dimensions and reducing the move time can give an increase in pretax profits of more than $600,000. A comprehensive bibliography is included.

Jan 1, 1977

By Thomas O. Glover

The mining industry of Cameroon continued to be dominated by crude petroleum. Crude petroleum production has become the most important facet of Cameroon's economic development. Oil production was estimated to be 6.3 million tons in 1983 compared with 5.2 million tons in 1982 and 4.3 million tons in 1981. Over two-thirds of its export income was attributed to crude oil. The country's only refinery, dedicated in 1981, has a production capacity of 2 million tons. Cameroon has become self- sufficient in petroleum products since commissioning the refinery. The oil sector contributed approximately 13.5% to Cameroon's gross domestic product in 1982-83. Oil production was expected to rise from 125,000 barrels per day in 1983 to 156,000 barrels per day in 1985 when output peaks. Cameroon's ultimate recoverable reserves have been calculated at 100 million tons, or 750 million barrels of oil.

Jan 1, 1985

By G. F. Kuncir

The analysis described herein evaluates the Bureau of Mines Program for Advancing Mining Technology - Oil Shale in terms of the economic benefits which may be derived for the Nation as a result of its successful research and development efforts. On the basis of postulated oil shale production scenarios, benefit-cost ratio indicators are computed for the program elements as they apply to surface, underground, and modified in situ oil shale mining systems. Eight value indicators are used to measure the Program's beneficial impact on the future oil shale industry in relation to planned research and development costs. These are: capital cost savings, operating cost savings, labor savings environmental quality maintenance cost reduction, reduction in production costs, byproduct production benefits, total production benefits, and additions to recoverable reserves. Program costs are aggregated from 1974 through 1987 and major benefits are accrued from 1982 through 2040. Both cost and benefit streams are discounted to mid-1975 present value.

Jan 1, 1977

PROFIL D'ENTREPRISE Léandre Gervais & Associé(e)s est une société d'experts-conseils en ingénierie de la structure, de la mécanique & de la tuyauterie, et de l'électricité et de l'instrumentation. Nous offrons des services hautement spécialisés à notre clientèle des secteurs industriels des mines et de la métallurgie, au Québec, au Canada ainsi que dans plusieurs autres pays du monde. Notre mission est d'assurer à nos clients un ensemble de services d'ingénierie de haute qualité contribuant à la mise en oeuvre et à la réalisation de leurs projets d'affaires. Léandre Gervais & Associé(e)s emploie 36 employés à temps pleins et opère à partir de Val-d'Or, province de Québec. SERVICES OFFERTS Nous avons réalisé de multiples mandats pour notre clientèle de différent pays du monde dans les domaines d'expertise les plus variés : ?Études de faisabilité ; ?Ingénierie conceptuelle ; ?Ingénierie de détail ; ?Gestion de projets ; ?Ré-ingénierie de la maintenance.

May 1, 2001

By R. M. Schuster, F. M. Benavides

Samuel G. Bonasso The article by Benavides and Schuster provides an in-depth study of three transportation alternatives for a four-mine complex in western Kentucky. The examination of aerial tramways was not undertaken as an alternative solution. We feel this is an oversight since industrial ropeways are competitive with both belt conveyance and overland truck hauling. In fact, there are aerial tramway systems, operational today, which are 100 years old and operating with some original components. Maybe unfortunately, there are no fixed rules or guidelines whereby the most cost-effective means of transporting and handling material for a given situation may be selected. Each situation must be evaluated so the variables that influence the selection of the desired alternative can be clearly defined. However, there are in-place industrial ropeway systems that have proven economically feasible over a range of 1.6-50 km (1-31 miles). The more difficult the terrain, the greater the cost efficiency.

Jan 1, 1983

By S. Badr, R. Mendoza, M. U. Ozbay, M. D. G. Salamon

ABSTRACT: The use of coal pillars at depth is fraught with problems due roof control difficulties and the possible occurrence of coal or pillar bumps. In the USA the largest and most important application of pillars at depth is in longwalling, where chain pillars are the customary supports of the multiple entry developments. At first, the chain pillars were designed using conventional approaches, where the principle is that the strength of the pillar should exceed the load imposed on it. Such approach to design led to larger and larger pillars at great depths, but instead of eliminating, it tended to aggravate the roof control problems. Eventually the idea was born that small sized yielding pillars, which have proved to be successful elsewhere, might provide the answer to this pressing problem as well. The aim of this paper is to study the modes of pillar failure at great depths, using two solution methods. The first of these comprises some elementary solutions obtained with the aid of a simplified conceptualization of the rock mass. This model consists of a strain-softening coal seam sandwiched between two stratified masses. The second approach utilizes FLAC3D, which is a commercially available three-dimensional numerical modeling software package. To gain a better insight, both the strain-softening and ideally plastic Mohr-Coulomb constitutive laws embodied in FLAC3D were exploited. As expected, the width to height ratio of the pillar has proved to be the primary factor that determined the behavior of the pillars. Narrow pillars fail in a stable manner without the occurrence of instabilities. Intermediate w/h ratio pillars under the appropriate loading conditions, may fail suddenly and may even collapse totally. Squat pillars do show the potential for sudden, coal bump like side failure, but because the remaining large width of the inner core, the ruble around the pillar provides sufficient confinement so as to reestablish stability. Finally, the study revealed that the traditional Mohr-Coulomb law does not provide a useful insight into the failure of coal pillars. RESUME: L’utilisation des piliers de charbon dans les mines souterraines de grande profondeur occasionne des problèmes due aux difficultés de control de plafond et possibles fracture ou explosions au niveau des piliers. Aux Etats-Unies d’Amérique, l’utilisation des piliers dans les mines souterraines de charbon comme moyen de support est considèrees comme étant la plus grande et la plus importantes des méthodes utilisée dans le ‘’ longwalling method’’ ou une série des piliers sont disposé de manière à supporter les multiple entrées d’exploitation de charbon. En premier lieu, cette série des piliers étaient construit de manière conventionnelle avec un principe basé sur le fait que le poids exerce sur les piliers doit être inférieur a la force que ces piliers exerce sur le plafond. Ce principe a conduit a ce que le volume des piliers augmente au fur et à mesure que la profondeur au de la mine augmente. Malheureusement, au lieu de résoudre le problème de support, ce principe n’a fait qu’aggraver le problème de contrôle de plafond. Eventuellement une idée s’est dégagé allant du fait que les piliers endommagés de taille moyenne qui se sont avérés être efficaces ailleurs, pourraient fournir un indice à ce particulier problème. Le but de cette recherche est celui d’étudier les différent types de ruptures qu’un pilier peut occasionner lorsqu’il est utilisé a grande profondeur, tout en utilisant deux possible méthodes. La première d’entre elle comprend quelques solutions élémentaires obtenues avec l’aide d’une méthode simplifié et conceptuelle de la masse de la roche. Ce modèle consiste à prendre en sandwich la bande de minerais de charbon entre deux masses stratigraphiques sans pour autant endommager le plafond. La seconde méthode nécessite l’utilisation du ‘’ FLAC3D’’, qui est un logiciel commercialisé disposant d’un modèle numérique en 3 dimensions. Dans le but d’obtenir

Jan 1, 2003

By A. Feldman

Measuring dynamic effects on existing structures such as dams and bridges during earthquakes or blasting is frequently done using strong motion detectors. However, a more comprehensive dynamic structural evaluation requires direct measurement of deflection, strain, and pressure changes during dynamic events. Many existing structures have vibrating wire gages already installed that can be used with modifications to the data acquisition systems to provide direct measurement of dynamic displacement, strain, and pressure. The project described in this paper provided the opportunity to demonstrate the feasibility of using vibrating wire technology to measure dynamic effects on existing structures.

Jan 1, 2006

By Peter Grundy

La eficiencia de los recursos en los procesos transparentes de gestión de las empresas permite aumentar el valor de los accionistas. En ese sentido, el presente texto señala el uso de la RCM como estrategia en el funcionamiento de un equipo que se centra en la confiabilidad. RCM es un proceso lógico que involucra aspectos técnicos y de negocio, capaz de producir resultados a muy corto plazo. Este proceso concluye con una recopilación de documentos fiables y totalmente óptimos para el desarrollo de las funciones de mantenimiento. Su uso correcto en la evaluación de los requisitos de mantenimiento de los equipos existentes, genera un mantenimiento menos costoso, confiable y eficaz. Asimismo se disminuye los costos de mantenimiento y se relaciona los aspectos ambientales y de seguridad.

Jul 17, 2000

By P. Klaus

"KfW IPEX-Bank is the commercial arm of KfW Bankengruppe, responsible for international project and export finance.KfW was one of the first banks in Germany to promulgate environmental guidelines for its commercial business activities. These guidelines were first made public in 2000 and updated for the second time in 2004. They now include specific reference not only to environmental but also to social concerns. The guidelines specify the procedures to be followed in assessing credit risks related to environmental or social hazards.The bank considers sustainability as an interdependent framework of economic, ecological and social factors. In its efforts to contribute to sustainable development worldwide the bank uses its influence as far as possible to improve a project’s performance if such improvement is deemed necessary."

Jan 1, 2005