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By Forrest T. Moyer

The overall disabling work injury experience, excluding office- workers, at nometal mines and mills during the period 1961-63, as reported to the Bureau of Mines by operators, was 77 fatal and 7,201 nonfatal injuries during an aggregate worktime of 335,029,685 man- hours. These injuries, fatal and nonfatal combined, occurred at a frequency rate of 21.72 per million man-hours, comprising 0.23 for the fatal and 21.49 for the nonfatal injuries. The combined severity rate of the disabilities was 2,312 days lost or charged per million man-hours, consisting of 1,379 for the fatal and 933 of the nonfatal injuries, The average severity of all disabilities during 1961-63, was 106 days per injury, The number of days lost or charged, excluding officeworkers, at nonmetal mines and mills during 1961-63, was 462,000 days charged to fatal injuries and 312,461 days lost from nonfatal injuries. The outstanding causes for fatal injuries were explosions (18 fatalities occurred in a major mine-explosion disaster in a potash mine in Utah in 1963) and falls of rock or ore from back or side, while most nonfatal injuries were caused by handling materials, slips or falls of persons, haulage, and machinery. The parts of the body most frequently injured during the period 1961-63 were the trunk, hand and finger, and foot and toe, An average of 52,810 men were at work daily, There were 20 nonfatal disabling injuries reported for office- workers at nonmetal mines and mills during the period 1961-63 during an aggregate worktime of 23,088,496 man-hours, These injuries occur- red at a frequency rate of 0.87 per million man-hours, There were no fatal injuries reported.

Jan 1, 1967

By J. Paraszczak

For mining companies facing strong international competition and unfavourable commodities’ prices, automation of underground operations has the potential to increase productivity and help cut costs. However, despite considerable technological progress in this field, there still remain many problems to overcome. Furthermore, successful implementation of automation depends also on numerous operational, organizational, and even human factors. In this context, this paper briefly reviews technological progress with regard to different underground operations. Following that, several issues related to implementation of automated equipment and systems are presented and discussed. Particular emphasis is put on the factors whose importance is often underestimated. Some recommendations in this respect are also given. It is stated that the success of an automation project is a function of many “winning conditions,” which may be created through very thorough planning and preparation. It is also underlined that despite achievements made, a vision of a man-less underground mine is not yet as much a matter of near future as it may seem.

Jan 1, 2004

By A. Redman

Aquatic organisms are sensitive to free cyanide (HCN) though the presence of certain metals that can form stable complexes and thereby reducing both the amount of bioavailable cyanide. Recent work has suggested that consideration of HCN rather than total cyanide can provide the basis for water quality criteria. Cyanide is often present in complex effluents that affect speciation and bioavailability. We have developed a model to predict the speciation of cyanide in complex effluents and have shown that this model can predict the toxicity of metal-cyanide complexes in terms of HCN. This study evaluated available cyanide toxicity exposures with this model to assess the role of water chemistry (e.g., metal-cyanide interactions) on the observed. Toxicity endpoints based on total cyanide ranged over several orders of magnitude for a variety of metal-cyanide mixtures. However, predicted HCN concentrations among these same tests described the observed toxicity data to within a factor of 2. Aquatic toxicity can be well described using HCN though in certain metal-cyanide mixtures toxicity was jointly described by HCN and elevated levels of bioavailable metals. This work was performed in support of an industry-sponsored reassessment (Gensemer et al 2006) of the U.S. EPA water quality criteria for cyanide (EPA 1985) using free cyanide as the basis for the re-calculation. The work presented in this manuscript presents technical support for using free cyanide as the preferred basis for this recalculation.

Jan 1, 2011

By M. Hakala, P. Tolppanen

A method to predict stress-induced failures around excavations based on the mapped geological and rock mechanical information is studied. Totally of 7 km of newly excavated tunnels are mapped in the Inmet’s Pyhäsalmi mine in Finland at depth between 1000 - 1440 m from which the results and conclusions from the firstly mapped 1.7 km of tunnels are reported. The main rock type at the site is very hard volcanite having uniaxial compressive strength of 230 MPa in median and GSI-value 72 - 80. The maximum in situ stress around the tunnels is 65 - 85 MPa. The prediction of observed stress failures was preceded by comparing elastic 3-D simulation results of tunnels with three statistical yield criteria. Read’s or Hoek & Brown’s yielding criteria are found the most relevant, though, the effect of anisotropy was found to be significant. The most important parameters having a correlation with stress failures are the tunnel orientation and the foliation of rock. Also, the rock type and its strength, tunnel shape and the geological anomalies have their effects. Further, a delay time on mapping was found to clearly diminishing of the most violent failures. Une méthode de prédiction des contraintes à la rupture autour d'excavation, établie sur la base de cartographie géologique et d'information sur la mécanique des roches, à été étudiée. Au total, 7 km d'un tunnel nouvellement percé à une profondeur de 1000 à 1400 m ont été cartographiés dans la mine de Inmet’s Pyhäsalmi en Finlande. La roche principale du site est une vulcanite dur ayant une résistance à la compression uniaxiale de 230 MPa (valeur moyenne) et une valeur GSI de 72 - 80. La contrainte in situ maximale autour du tunnel se situe entre 65 et 85 MPa. La prédiction des contraintes à la rupture observées a été évaluée en comparant les résultats d'une simulation 3D d'un tunnel avec trois critères de limite d'élasticité statistiques. Le critère de limite d'élasticité de Read ou de Hoek & Brown’s se trouvent être les plus important, même si les effets de l'anisotropie sont significatifs. Les paramètres les plus importants ayant une corrélation avec la rupture sont l'orientation du tunnel et la foliation de la roche. De plus, le type de roche et sa résistance à la compression, la forme du tunnel et les anomalies géologiques ont aussi leur importance. Finalement, un délai dans la cartographie résulte en une diminution nette des ruptures violentes. Basierend auf kartierten geologischen und felsmechanischen Informationen, wird eine Methode untersucht, um spannngsbedingtes Versagen um Ausbrüche herum vorherzusagen. Insgesamt werden 7 km neu ausgebrochenen Tunnels in einer Tiefe zwischen 1000 und 1400 m in der Inmet Pyhäsalmin Mine in Finnland kartiert. Das hauptsächlich vorkommende Gestein ist sehr hart und vulkanischen Ursprungs mit einer mittleren einachsialen Druckfestigkeit von 230 MPa (Medianwert) und einem GSI-Wert von 72-80. Die maximale In-situ-Spannung im Tunnel beträgt 65-85 MPa. Die Vorhersage von beobachteten Spannungsversagen werden weitergeführt indem man elastische 3-D-Simulationsergebnisse von Tunneln mit drei statistischen Fliesskriterien vergleicht. Read's oder Hoek's Fliesskriteria werden dabei als die relevantesten Kriterien angesehen, obwohl auch der Effekt der Anisotropie als wesentlich erachtet wird. Die wichtigsten Parameter für eine Korrelation von Spannungsversagen sind die Orientierung des Tunnels und die Schieferung der Gesteinsschichten. Desweiteren haben Gesteinsart, Tunnelprofil und geologische Anomalien ihren Einfluss. Ausserdem zeigt sich, dass eine Verzögerung bei der Kartierung die ausgeprägtesten Versagen deutlich verringern.

Jan 1, 2003

Outokumpu Technology’s HSC Chemistry process calculation software enables the user to simulate an entire chemical or physical process. The HSC Chemistry 6.0 contains 21 calculation modules and 11 databases for reaction, equilibrium, heat balance, heat transfer, petrological and simulation applications. Most of the calculation modules automatically utilize the same extensive thermochemical database which contains enthalpy (H), entropy (S) and heat capacity (C) data. This database has been expanded to include more than 20,000 species.

Jan 1, 2007

By M. Wong-Kian, L. A. Cornish, A. van Bennekom

Samples of four different satellite materials were prepared by either hot isostatic pressing (HIP) of the powder or tungsten inert-gas welding of rod onto a 316 L stainless-steel substrate. The samples were subjected to a series of comparative erosion corrosion tests, and generally the Hipped samples experienced between 13 and 24 per cent less loss in mass than the equivalent welded alloys. Resistance to erosion corrosion increased with increasing carbon, chromium, and tungsten contents. Metallographic studies indicated the differences in carbide content between the different satellite materials, and the differences in morphology between the Hipped and welded samples. Finer and more homogeneous microstructures were

Jan 1, 1995

By D. Harrington

We Americans fondly believe that ours is the greatest , most progressive and most civilized country in the world , but the cold statistical facts reveal that we apparently have little appreciation for the lives of those whose efforts of various kinds give us whatever greatness we have . The latest available statistics indicate that the annual death rate per 100,000 persons , from accidents is nearly 80 , or far higher than that of any other country in the world ; it is more than double the rate in Denmark , Belgium, Netherlands , France , Sweden , Italy , Ireland , Germany , Norway, and Austria; it is practically double the rate in England and Wales and in Japan , and is from 25 to 60 per cent higher than the corresponding rate in Scotland , New Zealand , Australia, Switzerland , and Canada . And added to this is the fact that of the main industries of the United States mining has by far the worst accident record , viewed from either the frequency or the severity basis . The National Safety Council's latest figures for 27 of the country's main industries give mining the highest or worst accident frequency rate, 74.43 in 1929 ; meat packing comes next with 55.94 , and construction third with 50.41 . In accident severity in 1929 mining also was the worst offender , with a rate of 9.99 ; quarrying is second with 6.11 , and construction third with 4.62 . Metal mining's frequency rate in 1929 was 52.16 , as against 69.25 for bituminous coal mining ,99.68 for anthracite mining, and 74.43 for the entire mining industry ; accident severity for metal mining in 1929 was 5.99 , as against 11.69 for bituminous coal mining , 10.87 for anthracite mining , and 9.99 for the mining industry as a whole . Although this figure indicated that metal mining is on a much safer plane than either bituminous or anthracite coal mining, the frequency rate of 52.16 for metal mining was higher in 1929 than the frequency rate of all but one of the other 26 industries about which data are available ; the metal mining severity rate of 5.99 , while much better

Mar 1, 1932

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963

By G. Vouille, P. Bérest

Residual stresses observed in rocks often result from non-compatible initial strains. These stresses can be determined when the incompatibility tensor associated with the initial strain tensor is known. The residual stresses in a cylindrical rock sample can be computed the sample is considered small enough for its incompatibility tensor to be constant. Les contraintes résiduelles, dont on observe couramment les manifestations dans les roches, résultent souvent de l’existence de déformations initiales non-compatibles. Ces contraintes peuvent être calculées lorsque le tenseur d’incompatibilité associé aux déformations initiales est connu. Les contraintes résiduelles dans une éprouvette cylindrique sont données dans le cas où le tenseur d’incompatibilité est constant. Eigenspannungen, die man haeufig in Steinen beobachtet, sind oft Ergebnis einer inkompatiblen Deformation des Anfangszustandes. Diese Spannungen koennen berechnet werden, wenn der Inkompatibilitaets-Tensor der Anfangsdeformation bekannt ist. Die Eigenspannungen einer zylindrischen Probe werden fuer Fall eines konstanten Inkompatibilitaets-Tensor bestimmt.

Jan 1, 2003

The Study of Jamesonite Flotation Behaviour

Sep 13, 2010

Overexposure to noise is a widespread, serious health hazard in the mining industry, and causes hearing losses to a large percentage of the mining population. Recognizing this fact, the Bureau has a major on-going research effort to address this problem area. These proceedings include an overview of the Bureau noise control program and summarize nine selected noise control research programs.

Jan 1, 1984

By Fred W. Snow

This paper describing the mining practices at the Magma mine, Superior, Ariz., is one of a series being prepared by the Bureau of Mines on mining prac¬tices, methods, and costs in the various mining districts in the United States. At present (1929) practically all the mineral production in the Superior district is from the Magma mine of the Magma Cooper Co. The ore is mined for its copper but contains associated silver and gold. Both direct smelting ore and ore of concentrating grade are produced. The mining methods now in use at the Magma mine were adopted or developed as knowledge was gained of the physical condition of the ore bodies and the inclosing formations; the wall rock is soft and crushed and the ore is relatively hard. In general, existing methods have been adapted to fit local conditions, but some of the mining practices used were originated at this mine. Most of the ore is mined by a combination of rill stopes and pillar stopes. The pillars are extracted by underhand mining.

Jan 1, 1929

By E. J. Babcock, W. W. Odell

The Bureau of Mines since its establishment has always taken an active interest in the utilization of lignite and in the development of the lignite dep'osits of the United States. Extensive lignite fields occur in the west central States, notably in North Dakota, Montana, Wyoming, Colorado, and Texas; there are smaller areas in several other States, some of which are widely separated. The total area of the deposits and the total amount of lignite in these several districts are so enormous that the economic value is seldom recognized. To the people of ·the west and west central regions, however, the larger utilization of lignite, in whatever form it may be, is of fundamental importance, and any new methods or uses that promise to open these great lignite fields for more general and more efficient use deserve careful study. Although these lignite deposits underlie areas of thousands of square miles, their development and general utilization has been rather slow. This is no doubt partly because many of the districts are not thickly settled or highly developed in manufacturing industries, but is largely because lignites, from their peculiar physical and chemical characteristics, are low-grade fuels. Most of the lignites in these areas are imperfectly developed coals; many have a more or less woody structure; some belong to the brown-coal type; and others are darker, denser, and more homogeneous, approaching subbituminous coal. The people living in the regions in which these vast deposits occur, especially in the west central part of the United States, are vitally interested in every effort toward bettering lignite as fuel and aiding its wider utilization.

Jan 1, 1923

By W. S. Dyer

Considerable attention has been paid in recent years to the fire-clay and silica-sand deposits of the Mattagami and Missinaibi rivers and ? to the lignite occurring in them. The fireclay especially deserves this attention; it is of first-class quality; it appears to be widespread; it is the only fire-clay in central Canada, and part of it lies not more than 20 miles west of Coral rapids, to which point steel will be laid this coming spring by the Temiskaming and Northern Ontario railway. Undoubtedly, these clays will rapidly find a place in industry. The fire-clays and the better grades of silica-sand are Mesozoic in age and have been referred to the Lower Cretaceous or Upper Jurassic. Glacial clays and sands and Palaeozoic shales also occur in the same region, but are of little economic value, and will not be dealt with in this paper. Dr. Robert Bell was perhaps the first to discover the clays, since in the Report of Progress of the Geological Survey of Canada for 1877 and 1878 he reported beds of lignite on Coal brook, a tributary of the Missinaibi river, underlain by sticky clay and overlain by glacial drift. In 1880 E. B. Borron (1) discovered an extensive deposit of white sand and clay on the east bank of the Missinaibi river, five miles below Coal brook, and in 1890 (2) he examined the deposit found by Dr. Bell on Coal brook. He recognized that the underlying clays were quite distinct from the glacial clays of the region, and suggested that they might be used for fire-brick if metallurgical operations were undertaken in the region. Somewhat later, J. M: Bell described a deposit of fire-clay and silica-sand on the Wabiskagami river, another tributary of the Missinaibi.

Jan 1, 1928

By Michel Rodrigue, Sylvain Duchesne, Louis Racine

"LocationThe Louvicourt mine is located 20 km east of Val d'Or in Abitibi, in the northwest part of the province of Quebec. The mine is located on Highway 117 connecting Val d'Or to Montreal and very close to the main railway networkHistoryFive successive exploration attempts by Aur Resources resulted in the discovery of the large Louvicourt orebody in June 1989. Construction of the surface and underground infrastructures commenced in the spring of 1991. Milling operations commenced in July 1994. The entire project cost CDN$290 million, almost CDN$20 million less than initially estimated. The concentrator infrastructure cost CDN$64 million.Louvicourt mine is owned in partnership by Novicourt Inc. (45%), Teck Corporation (25%), and Aur Resources Inc., the administrator (30%).Brief DescriptionLouvicourt mine is the largest producer of base metals (Cu and Zn) in Abitibi-Temiscamingue. Its average daily production is nearly 4300 t of ore, for an annual production of 200 000 t of copper concentrate (28% Cu) and 33 000 t of zinc concentrate (57% Zn). After only a few weeks of operation, it had attained its objectives for the most part, and operations continue to be improved."

Jan 1, 2000

By L. H. Michaud

"Albian Sands Energy (ASE), an oil sands surface mining and extraction operation, is currently undergoing start-up and is scheduled to ramp-up to full production by mid-2003. Startup includes the selection and implementation of over 75 IT systems or computer applications which include: engineering applications; systems required to control mining activities, maintenance, the processing plant and utilities; and also systems required to run the company, such as human resources, finances and inventory/ warehousing.This paper outlines the processes used for the selection, implementation and integration of these systems in order to optimize the use of information and to meet the technical, business and IT requirements of the company. The first step in ASE’s approach to identifying system requirements is the development of a business activity model, outlining all tasks involved in running the operations. The computer applications required to accomplish each task are then identified by having the IT team work closely with each technical and business unit. Historically, at some companies, the selection of systems has been led by the IT team or by consultants, with little input from the technical or business units. Typically, this results in products that do not meet the company’s expectations. To ensure a more positive outcome, ASE believes that it is imperative that the company’s technical and business people be closely involved in the selection process.Integration of the IT systems is also key, including linking all applications through a data warehouse and EDMS. Over 120 required integrations have been identified. This ensures the storage of all data in only one location, data security, and easy data and document retrieval for all requirements throughout the company"

Jan 1, 2003

By K. R. Coulter

"Good morning gentlemen. I am very pleased to have this opportunity to tell you a few of the things that happen within a completely unrelated activity, the electroplating industry, except that it does consume metals and has some slight similarity of problems so far as cyanide is concerned.First, just a few general terms about the industry. It is a relatively unsophisticated industry technically, and in many instances there are serious problems in obtaining staff that can operate the various systems that are currently available for destroying cyanide or precipitating metals.I would suggest to you that if you are investigating any system that you consider very seriously the personnel that are actually going to run it. The installation people; probably have some idea what it is all about but the operators must be chosen for their ability and not because they just happen to be available.We perhaps have another area in common. There is very little money for capital expenditures that produce no immediate return or even eventual return on the investment.The industry is largely made up of ""Jobbers"" who are strictly electroplating. There is another group in which the electroplating is captive as in large companions where it is a convenience operation. Also there are specialists, who do other things besides plating but it is a very major part of their operation. This applies to the automotive parts industry.Cyanide applications in the plating industry will be for copper, zinc, cadmium, silver, brass, and gold. Cyanide waste solutions come from those solutions adhering to the plated parts, and from the occasional discharge of the plating bath solutions. Also, in a related industry, the heat treating people with cyanide case hardening have some high concentrations of cyanide to dispose of. Concentrations of cyanide that we treat are 2500 parts per million or higher especially in wastes from heat treating. Solution volumes might be as low as 100 gallons per hour in a well run, carefully operated rinsing system. It may be as high as 3000 gallons per hour where dilution occurs."

Jan 1, 1973

By K. Biswas, F. C. Felipe

Paste backfill, because of its colloidal or water-holding properties, does not produce run-off water when placed underground. Paste backfill is generally, prepared from relatively low water content, full mill tailings with a certain proportion of ultra-fine particles and mixed with cement, thus producing early and better strength. Mill plant discharge tailings and other materials available at or near the mine site such as sand, aggregates or waste rock are used as blending materials in the mix design. This study investigates the influence of the above-mentioned blending materials on the mechanical characteristics of paste backfill, as well as the grading, shape, specific surface area, mineralogy and workability of the different mix design.

Jan 1, 2000

By P. Sun

Abstract: From the viewpoint of interaction mechanics of solid and gas, a coupled mathematical model is presented for coal/rock mass deformation and gas leak flow in parallel deformable coal seams. Numerical simulations for the prediction of the safety range of mining of protection layer are performed with experimental data from a mine with potential danger of coal/gas outbursts. Analyses show that the numerical simulation results are consistent with the measured data on the spot. Therefore, the coupled model shows a positive future for applications in a wide range. ZUSAMMENFASSUNG:Von der Veranschaulichung der Abhängigkeit Mechaniker für Körper und Gas, wird ein verbundenes mathematisches Modell für festen coal/rock Deformation und Gasleckstelle Fluß in parallele deformable Kohlenähte dargestellt. Numerische Simulationen für die Vorhersage der Sicherheit Strecke, die Schutzschichtbergbau verwendet, werden mit experimentellen Daten von einer Grube mit möglicher Gefahr der coal/gas Ausbrüche durchgeführt. Analysen zeigen, daß die numerischen Simulation Resultate mit den gemessenen Daten bezüglich des Punktes gleichbleibend sind. Folglich zeigt das verbundene Modell eine positive Zukunft für Anwendungen in einer breiten Strecke. RÉSUMÉ: Du point de vue de la mécanique d'interaction pour le solide et le gaz, un modèle mathématique couplé est présenté pour l'écoulement plein de déformation de coal/rock et de fuite de gaz dans les filons houillers deformable parallèles. Des simulations numériques pour la prévision de la gamme de sûreté employant l'exploitation de couche de protection sont effectuées avec des données expérimentales d'une mine avec le danger potentiel des accès de coal/gas. Les analyses prouvent que les résultats numériques de simulation sont conformés aux données mesurées sur place. Par conséquent, le modèle couplé montre un futur positif pour des applications dans un éventail.

Jan 1, 2003