Search Documents

By E. S. Chalpin

On 25 August 1971, the U.S. Bureau of Mines contracted with the Aerojet Liquid Rocket Company to perform an engineering research program to be completed on 25 May 1972. The program objective was to evaluate the advantages and disadvantages of the underground use of several power sources including but not limited to a closed cycle diesel, electric cable/motor, rechargeable battery/ motor and exhausting diesel for mine shuttle cars, with emphasis on health and safety. This report, Research in Advanced Power Systems for Mining Health and Safety consists of four (4) main parts: (1) Hazards and Safety Analysis of Mine Power Systems, (2) Evaluation of Closed Cycle Diesel Power System for Mine Applications, (3) Closed Cycle Diesel Power System Consumables Compatibility, and (4) Concluding Remarks and Recommendations. The hazards introduced to a mine by shuttle car power system failure modes were evaluated and reported. A "fault tree" analysis was generated for each power system and the probability of death or injury during an eight (8) hour shift and for a week of operation (105 hours) were estimated. Advantages and disadvantages were also reported for each system studied. Aerojet's assessment, based on a "forced decisions analysis," of the four shuttle car power systems as to their relative health and safety is that the exhausting or open cycle diesel is preferred, followed by the closed cycle diesel, the electric cable/motor and the rechargeable battery/motor. The assessment was based on ten parameters pertinent to the health and safety aspects of shuttle cars. Drawing layouts of two typical mine shuttle cars incorporating closed cycle diesel powerplant concepts are included in this report. The performance parameters established for the two concepts are tabulated. A study was made of the logistics involved in transporting and replenishing the consumables needed to operate a shuttle car equipped with a closed cycle diesel. The closed cycle diesel powerplant consumables -oxygen, potassium hydroxide, and diesel fuel - were analyzed as to their compatibility with materials found normally in a gassy coal mine. Spill tests simulating inadvertent leakage of liquid oxygen in a coal mine were performed. A critical evaluation of existing oxygen sensitivity data and the relationship to the use of oxygen on a shuttle car in a coal mine environment is presented.

Jan 1, 1972

The Anaconda Copper Company reportedly reached an exclusive agreement with Cook Inlet Region, Inc., to explore 24 million acres in south-central Alaska and to share equally with Cook the proceeds of any mineral discovery. According to an Anaconda geologist, "the company is anticipating, based on geologic testing, that it will find significant deposits of copper, lead, and zinc. There is also evidence of the presence of precious metals such as silver and gold, and also strong evidence of strategic minerals such as chrome, platinum, tin, and nickel." Cook Inlet Region, Inc., is owned by 6,500 Alaskan natives. Chile, which has a growing, free-market economy under President Pinochet, reportedly will no longer require companies to obtain prior governmental approval for the exploration and development of new mines.

Jan 1, 1981

By Orlando Martino

This regional report covers the mineral industries of Canada and 40 countries and areas in Latin America and the Caribbean Basin. Also included is a brief description of the mineral potential of Antarctica. The Latin American region encompasses an area twice that of the United States. Latin America and Canada have a rich and diversified endowment of mineral fuels, metals, and industrial minerals. Tables 2 and 3 provide a summary view of the importance of Latin America and Canada's output of its major mineral commodities in world mineral supply in 1989 and 1990.

Jan 1, 1993

By Michel Aubertin

Les rejets miniers sont communément utilisés, depuis plus de 60 ans, comme matériau de remblayage des chantiers souterrains. Les roches stériles et les rejets de concentrateur sont employés comme remblais car ils sont disponibles sur les sites miniers à un coût réduit pour aider au support de terrain. Le remblayage des ouvertures est également avantageux car il permet de réduire la quantité de rejets entreposée en surface. Dans les mines souterraines, le remblai des chantiers doit aider à maintenir un espace de travail sécuritaire, tout en favorisant la récupération du minerai et le contrôle de la dilution. Il est alors essentiel d'évaluer précisément les pressions exercées par le remblai sur les murs et sur les barricades installées près de la base des chantiers. Dans cette présentation, des solutions existantes pour évaluer les pressions dans les chantiers sont brièvement revues. Les auteurs présentent ensuite des solutions analytiques récemment développées à cette fin, qui permettent de tenir compte du transfert des contraintes du remblai aux parois des chantiers et des galeries. Les solutions proposées, qui sont basées sur la théorie de l?effet d?arche, prennent en compte l'influence de la géométrie des ouvertures et de la position des barricades. La méthode de calcul permet aussi de calculer l?effet des pressions d?eau pour un remblai partiellement ou totalement submergé. Les solutions s'appliquent au cas d?un remblai récemment mis en place, alors que l?effet de la pression interstitielle ne peut pas être négligé, et aussi à plus long terme sous une condition drainée. Des résultats expérimentaux et des simulations numériques sont utilisés pour valider les équations proposées. Les résultats analytiques et numériques montrent notamment que la pression totale sur une barricade peut être grandement augmentée par la pression d?eau, tandis que la contrainte effective peut être réduite par les pressions interstielles (par rapport à la condition drainée ou sèche). On discutera aussi des implications pratiques de ces résultats pour l?application des remblais souterrains.

Nov 1, 2008

By Jacek Paraszczak

For mining companies facing strong international competition and unfavorable commodities? prices, automation of underground operations has got a potential to increase productivity and help cut cost. However, despite considerable technological progress in this field, there still remain some problems to overcome. Furthermore, a success implementation of automation depends also on numerous operational, organizational and even human factors. In this context, this paper reviews briefly a 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 sometimes underestimated. Some recommendations in this respect are also given. It is stated that a success of an automation project is a function of many ?winning conditions?, which may be created through a very thorough planning and preparation. It is also underlined that despite achievements made, a vision of a man-less underground mine is not yet a question of near future as it may seem.

May 1, 2001

By Almon F. Robertson

This is one of a series of reports describing investigations made within the Missouri River Basin in Montana by mining engineers of the Bureau of Mines, Minerals Division, Region II. The primary purpose of these investigations is to provide basic information to agencies of the Department of the Interior and other agencies concerned with the planning of power and other water developments in the Missouri River Basin. This report contains only such factual data as have been authorized for public distribution. Special precautions have been taken not to reveal any information or data considered to be confidential. The field investigations for this report were made during the fall of 1948 and the summer of 1949. Virtually all of the known metallic mineral deposits and some nonmetallic (industrial) mineral deposits within Judith Basin County were investigated. Most of the mines and prospects have been inactive for many years; most of the old underground mine workings now are inaccessible or only partly accessible. Consequently, much of the information on many of the mines and prospects necessarily has been obtained from available U. S. Government and State publications and from owners and local residents.

Jan 1, 1951

By Richard D. Smith

The Bureau of Mines evaluated the emission control methods, including the capital investments and operating cost, necessary for further reducing lead levels in ambient air at the Glover, Herculaneum, and Buick smelter-refineries in Missouri and the East Helena, MT, smelter. The U.S. Environmental Protection Agency (EPA) has proposed more stringent lead in ambient air standards than those currently in effect. This report presents theoretically achievable lead emission reductions and estimated capital and operating costs. Lead emission inventories theoretically can be reduced from 1985 levels by 2,421 lb/d at the three Missouri operations by containing and filtering fugitive emissions within structural enclosures and baghouses. The aggregated capital and operating costs in 1986 dollars using conventional environmental and workplace technologies are estimated to be $250,014,100 and $18,507,800, respectively. Estimated total incremental cost is $0.063/lb as refined lead. Additional regulatory costs attributable to Occupational Safety and Health Administration (OSKA), U.S. Department of Labor, workplace standards are included since proposed environmental controls may otherwise degrade workplace conditions. Continuous drossing is evaluated as an alternative to conventional OSHA controls. Substituting continuous drossing for conventional work- place technology results in an estimated aggregated capital and operating costs of $258,344,800 and $15,719,600, respectively. Estimated total incremental cost is $0.062/1b as refined lead. For comparison, the average open market price of refined lead during the first quarter of 1986 was $0.184/lb.

Jan 1, 1987

By E Mare

Recent highly publicised incidences of disastrous containment failures, none more pertinent than the 2019 iron ore tailings dam failure in Brumadinho, have focused the world’s attention squarely on the often-challenging subject of tailings storage. Unwanted ultrafines, that are deemed to be unworthy of further treatment or not to have further saleable value, are therefore a significant issue for mine owners looking to reduce risks and perceptions associated with long-term storage of tailings. In this context, there are strong drivers to identify safer approaches to ultrafine tailings management, especially if it can also lead to increased revenue, together with better water stewardship and environmental outcomes. The better management of tailings needs to be considered from both containment challenge and processing opportunity perspectives. This paper focuses on the latter, reviewing from a technical and economic perspective, the feasibility of more extensive processing and/or reprocessing of specifically iron ore tailings, in a bid to reduce the overall volume for management in long-term storage. Herein the opportunity lies in recovery processing, as much as enhanced thickening and/or mechanical dewatering, and therefore the paper discusses both issues as equally important sides of the same coin. Recent interest in iron ore ultrafines processing and reprocessing studies suggests that the enhanced processing of iron ore tailings offers multiple perceived advantages. Apart from a potential reduction in tailings volume, associated with safer containment, lower environmental impact and improved water management, the prospect of increased revenue from additional Fe recovery presents supplementary motivation for iron ore players to embrace this approach, as further elaborated in this paper.

Nov 8, 2021

By W. L. EGY, GEORGES. RICE, L. M. JONES, J. K. CLEMENT

This report has been prepared, not only for the purpose of recording the results of the first series of coal-dust tests conducted in the experimental mine of the Bureau of Mines, but also to place before the mining public a description of the mine and an account of the objects sought in its establishment. Soon after the organization of the technologic branch of the United States Geological Survey, J. A. Holmes, then chief of the branch, concluded that for the solution of various problems relating to the causes and prevention of mine explosions it would be best to carry on large-scale tests in a mine rather than in a surface gallery. The idea of utilizing the underground passage of a mine for making explosion experiments did not at' first meet with general approval among investigators in this country or abroad. Many thought a mine passage was not a proper place in which scientific tests could be conducted, as great difficulty in controlling conditions was expected. However, after all arguments for and against such an investigation had been carefully considered, plans for opening an experimental mine were definitely adopted by the Bureau of Mines in 1910, and an allotment of funds was made to carry out the project. The first endeavor was to find an existing mine suitable for the purpose, but the mines offered by owners were either worked out, were wet, had poor roofs, or presented complications of various kinds, so that it was finally decided to open a mine if a site could be obtained having natural conditions that would fill the various requirements. A most desirable location was found on property of the Pittsburgh Coal Co., near Bruceton, Pa. The president of this company, Mr. W. K. Field, the general manager, Mr. G. W. Schluederberg, and the chief engineer, Mr. E. J. Taylor, rendered every possible service in

Jan 1, 1913

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

By E. D. Gardner

This bulletin, which discusses open-cut mining at the metal mines of the United States, is the last of a series of such papers by the Bureau of Mines describing the principal methods of mining.4 Open-cut mining is applicable to flat-lying mineral deposits relatively near the surface. Vein deposits seldom are amenable to this method, although outcrops of veins sometimes are worked as open pits. Most of the iron ore of the country is mined from open pits; according to the Minerals Yearbook, 67.4 percent was mined from open pits and 32.6 percent from underground mines in 1937. Open-cut mining is relatively new in the copper industry but yields more copper than any other method; in 1937 about 52 percent of the copper ore mined in the United States was taken from open pits. Lead-zinc ore has been produced from open pits in the Joplin (Mo.) district, but most of the deposits in this area, although flat-lying, are too deep to be mined economically by the open-cut method. In 1937 one company at Oronogo, Mo., was stripping overburden and mining mixed oxidized and sulfide ores by this method.

Jan 1, 1941

By D. M. Hausen

A computer program has been developed by Newmont Exploration to convert mineralogic data by XRD into rock type and ore type classifications. This method has proven useful in identifying lithology from cuttings samples, where percussion drilling was an alternative to expensive core drilling. Computer printouts of rock type and ore type identifications can be generated simultaneously with mineralogic analyses, resulting in a considerable time savings in manual calculation. XRD-computer logging was first applied to the Carlin mine in north central Nevada, and later to the Maggie Creek and Gold Quarry gold deposits, southeast of the Carlin mine. Impure Paleozoic limestones of the "lower plate" Roberts Mountain Formation and the "upper plate" transitional facies have been decarbonatized to altered siltstones and shaley units along vertical faults and permeable stratiform horizons. Advanced stages of decarbonatization were accompanied by silicification. Quantitative XRD data are initially sorted into principal rock type units (limestones, siltstones, dolostones, shales) based on major mineralogic components (calcite, quartz, dolomite, clays). On the basis of relative amounts of less major constituents, descriptive subclassifications (dolomitic limestones, dolomitic siltstones, argillaceous cherts) are made. XRD lithologic data provide assistance in correlating lithologic units, and delineating favorable replacement horizons associated with gold mineralization.

Jan 1, 1982

By Carl R. Peterson

[In lTI n,v und I'gr'oun nllnin~ Opt'I'ali n' the high . t cost is the loading and I 3ulage of t tln-of -D"'line ot'. 01' hauling costs can be r duced signifi-cant\v with the us ~ (r \) >It corn'e)'OI' " a COnlTllOn pl'acti c i.n coal and other s 0 t'L rn I n r' a l III i, n e , '. Jf 0 vel s i z ' () f' e can bee 1 i 11.11 tl ate I rH'i 0 I' lO C n v e . in g, ]

Jan 1, 1976

By H. O. Hofman

WHEN dry chlorine gas is made to act in the cold upon finely¬divided gold,' it converts the latter with evolution of heat into auro-auric chloride, Au2CI4, a hard, dark-red, hygroscopic salt. Moisture splits this salt into aurous and aerie chloride, Au2C14 = AuCI + AuCI3; treatment with water converts it into auric chloride and gold, 3 Au2CI4 = 4 AuC13 + Au,. Aurous chloride, when stirred with water, undergoes a similar decomposition, 3 AuCI = AuCI3 + Au,. These decompositions of auro-auric chloride and of aurous chloride furnish the explanation for the practice of moistening an ore before it is treated by the Plattner chlorination-process; practical experience having shown that gaseous chlorine gave an unsatisfactory extraction with dry ore. According to Rose,' fine gold is acted upon more slowly by chlorine than gold containing some base metal, e.g., copper. He also states that small quantities of silver increase the rate of solution, but adds that the coating of silver chloride formed checks, and finally stops, further action, if the percentage of silver be increased beyond a certain undetermined amount. Bromine' acts upon finely-divided gold in a manner similar to chlorine; the auro-auric bromide, Au2Br4, however, is not hygroscopic. Upon treatment with water it is decomposed as is the corresponding chlorine salt. It is generally believed that bromine does not act as energetically upon gold as does chlorine. This seems to be borne out by the results in the leach-

Mar 1, 1905

By Brian M. Harney

The technique of remote sensing, used for many years by earth scientists, is being applied to the detection and monitoring of air pollution. Instrumentation being developed is of a very diverse nature and is effective, Fn varying degrees, at ranges from 1,000 meters to the altitude of a space satellite. This paper describes a number of the recent developments in this new field. Instruments based on spectroscopic, laser, and photographic systems are discussed. Sensors are being developed which utilize correlation spectrometry, interferometry, Raman scattering, Mie scattering, laser line absorption, and simple photographic detection.

Jan 1, 1973

By P. R. Thomas

The Bureau of Mines determined the costs associated with the production of chromium, in the form of chromite and high-carbon ferrochomium, from the demonstated resources of 10 market economy nations. The analyses evaluated the relative geologic and economic position of these chromite resources contained within 80 producing or potential mining operations. This report presents cost evaluations of a demonstrated resource of chromite, contained within the nations studied, of appoximately 1.2 billion metric tons (t). Of this total, 70 pct is contained within the southern African nations of Zimbabwe and the Republic of South Africa. The majority of current chromium mining and smelting capacity is contained within these two countries as well. India and the Philippines have recently demonstrated greatly increased chromite resources and hold the most promise for expanding both chomite and ferrochromium production outside southern Africa. Their demonstrated resources represent approximately 7 and 16 pet, respectively, of the cost evaluated total tonnage. Chromite resources, on an identified or hypothetical basis worldwide, are highly concentrated within Zimbabwe and South Africa, with these two nations containing in excess of 95 pet of the total. Given the present market structure, a majority of chromium contained within the demonstrated chromite resources of the nations studied is economically recoverable; but from a long-term resource and economic perspective, South Africa should inceasingly dominate the markets for both chromite and high-carbon ferrochromium. In addition, it is anticipated that an increasing percentage of chromium traded on the world market in the future will be in the form of high-carbon ferrochromium as opposed to chromite, as this additional processing stage continues to relocate from the industrial nations that account for a majority of chromium consumption to those nations that mine chromite.

Jan 1, 1984

By R. W. Raymond

EDWARD COOPER, was born in New York City, October 26, 1824. His father, Peter Cooper, to say nothing of manifold reasons for fame as an inventor and philanthropist, deserves to be remembered as a pioneer in the establishment of public schools; and it is not surprising that he sent his son to one of the democratic institutions in which he was himself so ardently interested. From the public school Edward Cooper went to Columbia. College, where he made the acquaintance of Abram S. Hewitt, who was first his tutor, afterwards his traveling companion, brother-in-law, business partner and life-long friend.* For twenty years I was the consulting engineer of the firm of Cooper & Hewitt, and also connected with the work of the Cooper Union, in which they were both deeply interested and faithfully active. On the basis of the intimate knowledge thus gained, I venture an estimate of Edward Cooper's character and career which, if not fully comprehensive, may facilitate a juster estimate than would be reached by the strident of those data which the modesty of the man permitted to be placed upon public record. Edward Cooper's mind was one of the most active, accurate and subtle with which I have ever come into contact: He had inherited from his father a sunny, benevolent temperament, and' the irresistible impulse to attack all new problems which challenged his attention. His thorough education had 'indeed made him wiser than his father, both in philanthropy and in technical inventions. He could condemn and reject a proposition which Peter Cooper would have embraced, in a splendid, though ignorant, faith that nothing was impossible to an. American, and that the word ? impossible " was simply a label,

Jul 1, 1906

By C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013

This study assesses whether Narragansett Basin coal deposits could be developed commercially in the near future. To do this, we identify the potential market for the coal, assess the price these users would be willing to pay for Narragansett coal, and this price to the expected costs of producing Narragansett coal. The study concludes that the major market, New England utilities, could burn bituminous coal from Pennsylvania or West Virginia at a lower total cost than Narragansett Basin coal, assuming expected mining conditions and emission policies. Therefore, the study concludes that Narragansett Basin coal resources could not be developed economically in the next ten years.

Jan 1, 1979

By Thomas E. Howard

Man has been engaged in the construction of tunnels in. rock for several thousand years. During that time, methods of tunneling have changed drastically. Hordes of men chipping away at the tunnel face have been replaced by mechanical drills and explosives and by tunnel boring machines. Spoil is no longer carried on the backs of humans, but is now removed by trains, trucks or conveyor systems. These and other changes have had the effect of greatly increasing the rate of tunneling, while at the same time, greatly decreasing the potential dangers to workmen. Although the techniques, equipment and material used for tunneling are being continually improved, rock tunneling is still a slow and expensive process. Significant improvements and innovations are needed to reduce the cost and time required for tunneling if we are to fully utilize the subsurface to aid in the solution of urban problems and in the conservation of resources. This report is intended to facilitate the orderly development of tunneling technology by focusing attention on the inadequacies of rock tunneling and the improvements that are needed. The data presented were derived from the results of a comprehensive questionnaire that was completed during the summer of 1969 by more than 600 individuals and organizations in 17 countries. Table 1 lists the countries and the number of replies from each. Appendix A contains a summary profile of the national responses, while the text presents the results and a brief analysis of the conclusions that might be derived from the data in the questionnaire. The data shown in Appendix A represent the consensus opinion of each of the 17 nations without regard to the number of individual replies or the amount of tunneling activity that is represented. The national consensus was determined for each country by a plurality of the individual responses, in some cases modified by the opinion of the rapporteur. Tire above procedures can lead to situations which are misleading. For example, experience and activity arc a rational basis for analysis; but, if national replies are weighted on this basis (i.e., number of responses), informed and valuable opinion of less active countries would probably be overwhelmed and lost. In analysing the data on the basis of national responses without weighting, it becomes apparent that many of the same problems exist under a given set of conditions regardless of the number of tunnels that have been driven.

Jan 1, 1970