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By J. C. Thornley

Service failures of seemingly conventional galvanized bolts, in normal operation, on transmission towers in New Brunswick have been found to be the result of hydrogen cracking. In both these cases, similar failures elsewhere can be avoided by suitable clauses in the purchase specifications. In the first case described, the manufacturing procedure was responsible for strengthening and embrittling a standard, soft, constructional steel. In this case, a fracture mechanics analysis predicted critical crack depths for final fracture very similar to those found in practice. This case reveals an apparent cooperative connection between hydrogen embrittlement and strain ageing in plain carbon steels. In the second case described, the steel was simply a high strength steel which should not have been made into galvanized bolts.

Jan 1, 1979

By Robert W. Bruhn

Ground movements associated with high extraction underground coal mining, such as pillar retreat and longwall, are some- times large enough to disrupt the ground water regime as well as damage buildings and other surface structures. A U.S. Department of Energy Bureau of Mines- sponsored subsidence study at Kitt Energy Corporation's Kitt No. 1 Mine near Philippi (Barbour County) , West Virginia has provided an opportunity to monitor the ground water response above a mine panel during both developmental and pillar re- treat mining. Findings concerning ground water effects presented in this paper indicate that total extraction mining produced significant water level declines in deep-lying strata but had little effect on water levels at shallower depths. Post-mining values of hydraulic conductivity were typically somewhat higher than pre-mining values. Changes in water chemistry associated with mining were not sufficient to render the water unfit for human consumption.

Jan 1, 1986

By Brotzmann K, Turner RE, Philp DK, Rusden RC

New approaches in the last decade have led to the supplemental use of raw coal as a direct energy source in several iron and steelmaking processes. The dependence on more expensive coke and electricity is being progressively reduced. The Technology Venture of Klockner Werke and CRA has pionered several of these developments and is pushing ahead to processes for scrap melting and direct smel- ting of iron where coal is the ONLY energy source. Such complex developments depend strong- ly on the experience gained in the simpler but related processes for coal use already in operation. The longer term implications of a successful coal-based direct smelting process for the world steel industry are substantial.

Jan 1, 1986

By C J. Unger, T Baumgartl, C J. Bond, P Sabourenkov, V C. Glenn

Social licence to mine is influenced by society’s perception of the mining sector’s ability to effectively rehabilitate mined land and for governments to appropriately regulate that process for the broader community benefit. In Queensland, Australia, many mine rehabilitation personnel working for active coalmines, as either staff, consultants or contractors, belong to the Central Queensland Mine Rehabilitation Group (CQMRG). The CQMRG was established 23 years ago with the aim of sharing informal knowledge related to practical aspects of rehabilitation in order to leave as positive a legacy as possible from mined land. This voluntary group of professionals also includes members from regulatory agencies and civil society. Within the dynamic regional mining environment, mine rehabilitation professionals benefit from sharing their informal knowledge.CQMRG is currently a group in transition. Mining boom and downturn cycles have exacerbated the loss of accumulated knowledge in the core CQMRG membership due to rapid changes in personnel at mines in the region. Additionally, some of the most experienced CQMRG-affiliated rehabilitation practitioners are approaching the end of their careers and want their valuable and less formal knowledge retained. This paper discusses the development of a research project that emerged in response to the anticipated loss of several decades’ worth of valuable knowledge as rehabilitation practitioners in CQMRG left the region or the workforce.CITATION:Unger, C J, Bond, C J, Baumgartl, T, Glenn, V C and Sabourenkov, P, 2016. ‘MRC-wiki’ – a mine rehabilitation and closure knowledge management tool for Central Queensland coalmine practitioners, in Proceedings Life-of-Mine 2016 Conference , pp 39–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Daniel I. Carey

Current and potential dragline reclamation usage was evaluated for the U.S. coalfields based on data gathered and analyzed during field surveys, literature reviews and contacts with manufacturers. It was concluded that current wining plans have been adapted to federal and state strip mine and reclamation laws in ways which limit the potential for drag line reclamation systems at active mine sites. At abandoned conventional contour mine sites in steep-sloping areas such as central Appalachia, however, it was found that dragline reclamation systems have great potential application and may be the only practical solution to many reclamation problems. Alternative dragline systems were examined for restoring abandoned sites, and it was concluded that a tower excavator system offered superior characteristics and should be evaluated and developed under field conditions. A testing program was developed to provide a framework for the monitoring and analysis of cost, production and environmental data during a field demonstration of a tower excavator system.

Jan 1, 1981

By Eugene Frey

"INTRODUCTION The Iron Mountain deposits were examined in the summer of 1943 by engineers of the Bureau of Lanes, and a diamond-drilling project was set up under the Strategic Minerals Program. Actual drilling operations, under the supervision of a Bureau engineer, commenced November 9, 1943, and were completed on November 1, 1944. When the Bureau began detailed exploration of the Iron Mountain deposits, the Federal Geological Survey participated. Dr. I. W. Newhouse, of the Survey, and Dr. A. F. Hagner, of the Wyoming Geological Survey, were assigned to the investigation.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.With respect to this report, acknowledgment is made to S. R. Zirrmerley and F. T. Allsman, Bureau of Mines, Salt Lake City, Utah, who supervised the work of this project."

Nov 1, 1946

By IPMI Educational and Scientific Foundation

It is with great pleasure that we announce the availability of this fourth issue of the IPMI Journal, a publication of the International Precious Metals Educational and Scientific Foundation. This digital peer reviewed publication has been created as a vehicle for the sharing of technical information related to the science and technology of precious metals. Since 1976, the International Precious Metals Institute has championed the exchange of information of critical importance to the precious metals scientific and commercial communities through its various communications vehicles. This has included instructional videos, annual conference symposia, special topic committee meetings, regional seminars, and professional and student achievement awards. Due to the breadth of important topics related to all aspects of precious metals, it has been the vision of the IPMI to provide a publication available to the general public that would become a key source of pertinent topics containing high quality publications by experts in their fields of study. Historically, the IPMI has attracted world renowned experts in many fields (including Nobel Laureates Henry Taube, Ei-ishi Negishi, Robert Grubs, Professor Ben Feringa, and David MacMillan) in the dissemination of discoveries, inventions, and industry proven practices. Such information has a total value greater than the sum of its parts as seemingly unrelated innovations from distinct focus areas can be adapted to solve problems. Because of this important characteristic of information exchange, we have decided to create a digital journal, available to the general public, that will not only communicate state of the art discoveries and sound practices, but will also review historical communications from the IPMI’s archives that have value and use even in today’s environment. On behalf of the members and leaders of the IPMI, we hope you will find value in this new publication.

Dec 1, 2021

By Joseph D. Davis, GEORGE S. POPE

This bulletin is the fourth of a series a showing the results of the purchase of coal by the Government under specifications. The work of inspecting and analyzing coal delivered on Government contracts was transferred to the Bureau of Mines by an act of Congress effective July 1, 1910. It had been carried on for several years before that date by the technologic branch of the United States Geological Survey. The purchase of coal on the dealer's statement as to quality or on the reputation of the mine or district producing the coal is gradually being discontinued. At present most coal-purchasing contracts make definite provision regarding the desired heating value of a coal and the composition as shown by analysis. The heating value is usually expressed in British thermal units" and the composition specified is that shown by proximate" analysis. The price to be paid for delivered coal is made to depend on whether the analyses and heating-value tests of samples representing the delivery show the quality to be above or below the quality set forth in the contract. Large coal consumers are beginning to appreciate more and more the importance of the cost of power as a factor in the cost of producing a finished article. The endeavor to increase the efficiency and the economical operation of a power plant calls for an intimate knowledge of the quality of the coal being used. The purchase of coal under specifications insures the purchaser getting what he pays for and the coal being of the quality guaranteed. In addition, the analyses and tests of the delivered coal furnish data whereby the power-plant results can be comprehensively studied and a continuous check maintained on the conditions of operation.

Jan 1, 1912

By Nien-Yin Chang

The contemporary seismic response analysis of structures using a finite element analysis code requires six elastic spring constants to address the six degrees of freedom ground/foundation contribution to the response of a structure to earthquake shaking. However, the ground response is nothing but linear. Thus, it is critical to address the effect of the nonlinear ground response to the performance of structures under strong earthquakes. This study specifically addresses the effect of pile foundation on building vibration using finite element analyses. The effect of single pile was first investigated and the load was applied at the pile head using the single-degree-of-freedom load at a time, including three translational loads in the x, y and z directions and three moment loads about the three respective axes. In this study, the coupling effects between two or more different loads were not investigated. A load is increased monotonically to investigate the nonlinear behavior of pile under various loads. The Mohr-Coulomb model was used to represent concrete. To explore the effect of soil models on the nonlinear spring functions, the following constitutive models of soils were used: linear elastic, Mohr-Coulomb model, Cap model, modified Cam-Clay model, and Duncan-Chang hyperbolic model.

Jan 1, 2007

By E. P. Hayes

This report supplements the date contained in Bureau of Mines Information Circular 6156, "Special features of core drilling in the salt beds of Western Texas and New Mexico," by J. S. Wroth. That circular dealt with the drilling of the first 12 of the 24 potash tests made by the U. S. Bureau of Mines in cooperation with the U. S. Geological Survey; this report is concerned with the drilling of the last 12 tests. ACKNOWLEDGMENTS The writer is indebted to R. E. Heithecker, the Bureau of Mines engineer who had charge of the drilling of tests 13 to 17, for his well-prepared records on the drilling of these tests.

Jan 1, 1933

By Frederick H. Raab

The electromagnetic retransmission system is a new, automated method of locating trapped mine workers. This technique overcomes many 1 imitations inherent in electromagnetic direction finding by reducing the effects of the conducting ground to an acceptable maximum, by finding position accurately in the presence of antenna tilt, and by eliminating the need for the receiver to be located directly above the subsurface transmitter. Three transportable three-axis magnetic-dipole transmitters on the surface create a system of electronic grids in which the phases of the downlink Signals convey position information. The subsurface retransmitter modulates the uplink carrier of the existing beacon transmitter with the received downlink signal; the coal-pillar loop antenna is used for both receiving and transmitting. The uplink receiver uses a three-axis antenna and extensive digital signal processing. A small computer integrates data, estimates position, and controls system operation through VHF-FM communications. Both coal-mine and deep-mine operation are possible by selecting appropriate transmitting power and signal frequencies. This report shows such systems to be both feasible and practical.

Jan 1, 1980

By J. W. Thompson, M. N. RICH

That there is wide interest in the preparation and properties of metallic zirconium and its salts is indicated by the many articles recently published in scientific and technical journals and the many patents issued. The compounds of zirconium have numerous important uses and more uses will doubtless be found. In the course of the special work on rare metals that were of military importance during the war, the authors of this bulletin were detailed to the Golden mining experiment station of the Bureau of Mines to prepare metallic zirconium and to investigate its properties. A number of investigations in recent years have indicated that sintered or coherent zirconium metal is very resistive to acids; that it can be used for electrodes, and it probably will find metallurgical uses. A steel containing zirconium has been proposed for use in armor plate and automobile parts, and nickel-zirconium alloys have been suggested for high-speed cutting tools and for cutlery. Numerous articles in scientific journals have recommended the use of zirconium oxide as a refractory, an abrasive, a pigment in paints, and as an opaquing agent in enamel ware. The salts have been used in the textile industry' as a mordant and also for weighting silk. When the authors began their investigation, they found it necessary to collect all of the available literature on the general subject of zirconium and its compounds. Pure salts could not be obtained on the market, and in order to get these, as a preliminary step to the preparation of the metal, the literature had to be classified and the methods of preparing the salts investigated. Also, there was much difficulty at first in making satisfactory analyses, and this phase of the work received careful attention. As it was necessary to begin with a historical review of the literature, such a review is given as Part I of this report, and a bibliography is included as Part IV. References to the numbered items in this bibliography are made throughout the text, the usual footnote references being omitted. Analyses of the products and conclusions as to their purity are given under the descriptions of methods of preparation. A table showing the properties of the amorphous metal, and another showing the properties of the coherent metal, will be found under appropriate headings in Part II. No attempt has been made in the historical review to discuss fully all the published information about zirconium and its compounds, but only such material has been assembled as has a direct bearing upon the present work. Considerable difficulty was experienced in collecting this material because of the confusion of terms by various authors who perhaps did not thoroughly understand the chemistry of zirconium.

Jan 1, 1921

By SME SME

NORTH AMERICAN TUNNELING 2024 PROCEEDINGS

Jun 23, 2024

By J. L. Bowlby

The heats of combustion of fuels are determined in the laboratory by means of a calorimeter, usually of the oxygen bomb type. A known weight of the fuel is burned in an atmosphere of oxygen under approximately 400 pounds pressure in a heavy metal container-the bomb- and the heat evolved is imparted to a definite quantity of water. From the rise in temperature, measured by means of a Beckmann thermometer, and other data incidental to the determination, the heat value of the sample can be calculated. On paper, the method appears simple indeed, but in practice the determination of the heat of combustion is one of the most difficult of the various coal analyses. This h as led to considerable investigational work in order to obtain formula: whereby calorific values of solid fuels could be calculated from proximate analysis data al one. The proximate analysis of a fuel consists of the determination of moisture, ash, and volatile matter, with fixed carbon by difference. Sulphur determinations properly belong to the ultimate analysis, but in this section of the country, where the sulphur content of the coal is comparatively high, a request for the proximate analysis of a fuel implies the determination of the sulphur as well.

Jan 1, 1929

By G. L. Oldright

As a rule, the usual zinc retort smelter fired with natural gas made its own burners, of which there might be 300 per block, out of standard pipe fit-tings. The gas was discharged through a feeder pipe at various distances into a cylindrical horizontal "blow hole" through a pillar block and thence into the furnace; the best location of this gas-feeder pipe was at the horizontal central axis of the blow hole; the side entry into the blow hole usually was used. The air entered the same blow hole behind the gas, through a short nipple, in the inner end of which was a constructing orifice in a clay plug; in this ,work cone-shaped funnels of various lengths also were used. Even with the air and gas correctly proportioned to each burner, small differences in their dimensions were found to influence greatly the temperatures reached, their uniformity, and consequently the percentage of zinc extracted. This fourth paper of a series on cooperative work in the zinc retort plants of the Eagle-Picher Mining & Smelting Company discloses the methods and principles followed in approximating closely the optimum dimensions for various burners, with examples from experimental and commercial furnaces showing the interrelation of such dimensions with combustion and temperatures in the furnace.

Jan 1, 1948

This appendix contains the list of equipment, their corresponding number and their specifications with the quotations from the vendors/ manufacturers who can supply this equipment. The listings are arranged by process plant areas.

Jan 1, 1979

By David L. Veith

This Bureau of Mines bibliography of U.S. and Canadian literature pertaining to revegetating coal-mined lands contains 805 references published from 1977 to 1984. Each reference is evaluated by keywords, providing the reader with a means of rapidly sorting through the references to locate only those dealing with the coal mining region and subject of interest. All references are annotated. Other sources of information are given, including Office of Surface Mining (OSM) and State reclamation agencies and other published bibliographies.

Jan 1, 1985

By Barnard Foo

Topics of Discussion ?Location ?Production & Mining Operation ?Mineralization ?Mining Method ?Rock Mechanics Issues ?Ground Control Problems ?Numerical Analysis ?RockmassBehaviour ?Conclusions & Recommendations ?Discussion

Feb 1, 2008

By Richard S. Fowkes

Advanced technology, including automation and computerized information systems, is being adopted in mining at an ever-increasing rate to improve safety and productivity and to decrease overall costs. This U.S. Bureau of Mines report focuses on the human factors issues related to advanced technology. Among the significant facts discovered were the following: Experts studying tile design adoption, and implementation of new technology have stated repeatedly that human factors specialists should be involved from the early planning stages, through design and fabrication, and up to and during production, since human factors has been consistently identified as the biggest obstacle to the efficient utilization of new technology. Also, middle management is generally the greatest obstacle to the adoption of advanced technology, this technology can give rise to worker alienation, boredom, stress, job insecurity, and a sense of isolation; training most of the present work force is more cost effective than hiring new workers; workers are willing to accept new technology if they are given a voice in its implementation; the social and the technical systems should be jointly optimized; and with the intro¬duction of advanced technology, the cognitive or mental, rather than the physical, aspects of human-machine interaction must be emphasized.

Jan 1, 1994

By SANDEEP KUMAR JENA

This review work reports the recovery of potassiumfromdifferent rocks and mineral sources. The global demand for potassiumis rising consistently due to the growth of agricultural production. A major portion of the world potassium production is consumed in making of fertiliser; however, other uses include those in pharmaceutical, glass, ceramic, food and detergent industries. The availability of soluble potash minerals (sylvite, kainite and carnallite) in different countries like Canada, USA, Israel and Russia makes them as major potash producers, whereas agricultural-based countries like Liberia, Somalia, Central African Republic, Thailand, Indonesia and Malaysia including India meet their potassium requirement through import only. On the contrary, the availability of huge potassium-bearing rocks/minerals (like nepheline syenite, feldspar, mica, glauconitic sandstone) in these countries containing around 4–17% K2O would be a prospective for commercial production of potassium. The potassium recovery from minerals/rocks is very complicated due to the uniform distribution of potassium throughout the crystal structure. Different physico-chemical separation methods like bioleaching, chemical leaching, flotation and roast leaching have been discussed for the successful recovery of potash values from these rocks/minerals. However, the recovery of potassium from hugely available seawater using the chemical precipitation, solvent extraction,membrane separation and ionic exchangemethods is not cost-effective due to the low concentration of potassium.

Aug 31, 2020