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By Warren Howes, A. B. Campbell, W. H. Ode

"INTRODUCTION The mines in the eastern part of the now active region of the Tri-State zinc district of Missouri, Kansas, and Oklahoma have unusually acid water, which during periods of moderate or no rainfall is used in the mills to replace losses from evaporation, seepage, and tailings disposal. Its use has caused difficulties by corrosion of equipment and by interference with flotation.The growing importance of flotation, which requires good water, and the increasing troubles caused by the corrosion of the milling equipment have prompted the Mississippi Valley Experiment Station of the United States Bureau of Mines, in cooperation with the Missouri School of Mines and Metallurgy, Rolla, Mo., to investigate the action of the waters on flotation and to undertake to develop means of obviating their harmful effects.The work was under the immediate direction of W. T. Schrenk, consulting chemist, United States Bureau of Mines, and professor of chemistry, Missouri School of Mines and Metallurgy, and Will H. Coghill, supervising engineer of the ore dressing section of the United States Bureau of Mines.ORIGIN OF ACID MINE WATERSRain water, carrying oxygen and carbon dioxide in solution, finds its way into the pores and crevices of the earth's crust and percolates downward through the rocks. This water and its dissolved gases exert a solvent action on many minerals, the extent of which depends upon the nature of the associated minerals.The iron sulphides are the chief sources of the 'trouble with sulphates and sulphuric acid because they oxidize so freely and contain more sulphur than is required to satisfy the iron when ferrous sulphate is formed. Galena and sphalerite may oxidize to sulphates without liberating acid. A few of the common reactions occurring in the Tri-State mine waters may be illustrated by the following equations:"

Mar 1, 1932

By Richard E. Thill

The Bureau of Mines' Oil Shale Data Bank (OSDB) was created in 1976 to serve as a centralized source for the storage, retrieval, and dissemination of technical literature, patents, and information on research projects in oil shale. Thousands of bibliographic references, patents, and research projects relating to the mining of oil shale have been identified, abstracted, and indexed according to selected keyword topics. The resulting data bank listings are contained in three sections, each with a separate keyword breakdown for use in rapidly identifying references pertaining to a specific subject. All references cited in the OSDB were published prior to an established cut-off date of May 1, 1981, when a redirection of Bureau of Mines programs resulted in the loss of project funds and the subsequent phasing-out of data bank operations. ACKNOWLEDGMENTS The oil shale data bank listings are the result of a team effort of the project staff. The contributions of Jimaleen Jansma for keypunching, information acquisition, and data entry, and John Brandenburg and Sandra Brake for keywording and information acquisition are gratefully acknowledged. Appreciation is expressed to the staff members of the Smithsonian Science Information Exchange, Washington D.C. for their cooperation in supplying data on recent research projects in oil shale for inclusion in the OSDB listings. Appreciation is extended also to the staff of the Gallegos Research Group for assisting with computer services to obtain the final printouts and transfer of files onto magnetic tape.

Jan 1, 1982

By D. Harrington

When the word "gas"' is mentioned in connection with mining almost invariably it is inferred that the explosive gas, methane, is in mind and that the reference is to coal mining. Although methane is likely to occur in any coal mine the metal mines of the world contain by far a greater variety of gases than do the coal mines. Often the gases in metal mines are as dangerous as the gases likely to be found in coal mines, and sometimes are even more deadly. A coal mine is more likely to contain methane than a metal mine. In rare instances it may contain high percentages of nitrogen or carbon dioxide or it may be deficient in oxygen where the air is confined in a blind end or in a sealed region. Much more rarely relatively small percentages of ethane or other hydrocarbons with an odor of ether, gasoline, or kerosene, or minute percentages of hydrogen sulphide are found in a coal mine. During a coal-mine fire or explosion carbon monoxide content is likely to be high (4 per cent or more), and if the coal contains much sulphur the high fumes may contain some sulphur dioxide.

Jan 1, 1931

By Roger F. J. Adam

This report summarizes the principles of safely working steep coal seam using longwall mining methods. It presents the state-of-the-art and identifies the problems which result from seam inclination. Details are given on foreign longwall faces achieving good records of safety and productivity when mining on 30 degree and 50 degree inclined seams. Recommendations for further research are suggested.

Jan 1, 1981

By Daniel G. DiCanio

This report describes a computer-based model for estimating the tangible costs of injuries and deaths from work-related accidents in underground coal mines. The study undertook to identify and quantify the elements of accident costs, including field visits to coal mines, insurance carriers, and public agencies. The mathematical models developed for each tangible element of accident cost are presented in Volume I -of the report. A listing of the computer programs which comprise the model and instructions for using the programs are presented in Volume II. Statistical distributions of mining family characteristics, data on 95 miners killed in underground accidents, and other basic data used to develop the model are presented in Volume III. Application of the model to a data base of 9,286 accidents which occured in underground bituminous coal mines during 1974 yielded a total of $56,900,000 in tangible costs to industry, mining families, and public agencies. Loss of income to the families of miners injured or killed in these accidents accounted for 47 percent of the total.

Jan 1, 1976

By Raymond P. Miller

This two volume report addresses slope stability of surface mine spoils within the Interior Coal Province. Sixteen (16) mines were visited, pertinent data and samples collected, and reported spoil instabilities back-analyzed. Laboratory test results are compared to back-analyzed material properties. Available methods of slope stability analysis are reviewed and evaluated with respect to application to mine spoil stability evaluation and prediction. Correlation and tentative relationships among spoil material properties, highwall conditions, mining equipment and procedures and empirical observations are presented. Slope stability sensitivity plots illustrate the relative significance of various input parameters on stability. Slope stability input parameters are correlated with site and mining conditions to identify the primary factors controlling spoil stability. Investigative methods, spoil stability enhancement techniques, spoil stability prediction procedures and future study areas are discussed. Appendices include a glossary of terms, annotated bibliography, details of mine visits, and detailed laboratory test procedures and results.

Jan 1, 1979

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 A. Ploszajski

This item examines the history and uses of tungsten, from discovery to superalloys via the lightbulb and electron beam instruments.

Apr 1, 2015

By Raúl Prebisch

Continuando con el análisis de la realidad latinoamericana, el presente texto señala los factores estructurales internos de la insuficiencia dinámica de desarrollo latinoamericano como la absorción productiva de mano de obra, el aumento de productividad y necesidad de nuevas inversiones, los motivos principales de la insuficiencia dinámica, acumulación de capital, el obstáculo de la tierra, el funcionamiento de la estructura social, la inflación y la estructura social, los tipos de capital extranjero y la planificación y funcionamiento del sistema económico.

May 1, 1964

By Terry R. Guilinger

A minitest of the new potassium chloride-potassium carbonate two-stage in situ uranium leach process has been carried out at the Intercontinental Energy Corporation (IEC) Zamzow project site in South Texas. Substantial quantities of high concentration uranium were produced indicating the viability of the leach solution. The test results yield information regarding the reservoir dispersivity, the average cation-exchange capacity of the formation, and the distribution coefficients describing carion-exchange reactions. The test a1 so indicates permeability anisotropy and the existence of disturbed flow fields. The research was partially funded by the U.S. Bureau of Mines.

Jan 1, 1984

By F. M. Boler

The U.S. Bureau of Mines conducts research at the Galena Mine, Wallace, ID, with the aim of mitigating the effects of rock bursting. Destress blasting is commonly used as a stress control technique at the mine. A digital seismic array and an array of borehole pressure cells (BPC's) had been installed near the site of a stope undergoing mining and periodic de stressing. The instrumentation was being monitored at the time of a destress blast of the 46-99 stope. No significant seismic events occurred coincident with the destress. However, the destress was followed by a 2 ½ -week period of increased seismic activity, including two damaging events on February 7, 1990, at 034500 (hour, minute, and second) and 122020 Pacific standard time. BPC measurements indicated coseismic ground pressure changes on the order of 200 to 300 kPa associated with the damaging events. Fault plane solutions and dislocation models established that stress changes induced by the event at 034500 may have been significant in promoting the occurrence of the event at 122020. Theoretical investigations suggest that applying knowledge of the existing stress field, an understanding of rock burst mechanics, and fracture mechanics principles can improve destress effectiveness.

Jan 1, 2010

By J. P. Schde

The authors deal with nickel production and usage patterns, nickel's first-use and end-use, examples of nickel applications in modern technology, e.g., energy generation and conservation, environmental protection, the oil and gas industry, construction and machinery, food production, conservation and distribution, consumer durables and the like. A special section of the paper is devoted to new applications of nickel in the electronic industry, modern corrosion control and the building and construction industries. The need to defend traditional markets for nickel while striving to find new applications, is also stressed.

Jan 1, 1988

By E. D. Gardner

A general survey of the mineral industries of the Black Hills is being made by the Bureau or Mines, but this report is confined to the tin deposits of that region. Because of the strategic importance of tin in a national emergency, special attention was given in the field to deposits of this metal. The present paper outlines the procedure that would be required for determining the potentialities of the most promising deposits as emergency sources of tin and gives estimates of the cost of sampling and rehabilitating some of the old tin mines. Tin mining in the Black Hill was quiescent in 1938. Tin occurs in two areas inn the region. The deposits have received considerable attention, and since 1884 numerous articles have been written about them. It is estimated that between 7 and 15 million dollars has been spent in promotion expenses, acquiring claims, development work, and equipment; production, has totaled about 160 long tons of metallic tin worth about $95,000.3/

Jan 1, 1939

By Yan Yuan

Stable Nitroxyl polymers, such as poly (2,2,6,6-tetramenthyl-1-piperidinyloxy-4-yl methacrylate) (PTMA), are known to be effective as cathode active materials for lithium rechargeable betteries.The nitroxide radicals displayed a reversible and very rapid redox performances.We present a new synthesized method to get PTMA powder, then a doctor-blading method was used to prepare the PTMA composite electrodes, enabling successful production of homogeneous electrodes. It was characterized through FT-IR and SEM methods.The organic radical battery consists of lithium metal anode and PTMA cathode with an active material content of 65wt%.The best performance is achieved with a thin cathode that shows nearly 100% utilization of the active material (111mAh/g) at 0.1C.Through the electrochemical tests, it was found that there was a stable plateau at 3.5V while discharging. Besides, the cycling stability and rate capability were measured in detail. Although they showed a certain quantity of irreversible capacity on the first cycle, the capacity stabilized after the second cycle.

Jan 1, 2009

By Greisson Peixoto Rangel

A variação da resistência à compressão de argamassas geopoliméricas foi estudada em função da razão ativador/precursor e da molaridade da solução ativadora. As argamassas estudadas foram confeccionadas com metacaulim (precursor) ativado com solução composta por hidróxido de potássio e água destilada, e areia normal brasileira. De acordo com os resultados, a resistência aumenta com a diminuição da razão ativador/precursor e com o aumento da molaridade da solução ativadora. Além disso, os valores encontrados condizem com os presentes da literatura e com possíveis aplicações para argamassas de múltiplo uso.

Oct 30, 2017

A maximum acceptable level of 2 mg/m3 of respirable coal mine dust in active mine workings was established, effective January 1, 1973, under the Federal Coal Mine Health and Safety Act of 1969. It is generally agreed that, as a result, coal mines in the United States are significantly less dusty than they were a decade ago. For example, operators of underground mining machines were exposed to between 3.9 and 6.5 mg/m3 of respirable coal mine dust during 1968-69; now they are exposed to between 1.3 and 1.8 mg/m3. Also, the incidence of underground sections cited for exceeding acceptable levels of respirable coal mine dust decreased during 1976-78, and the vast majority of all working sections are now in compliance. This improvement is very substantial by world standards. It must be regarded as a creditable accomplishment by the coal mine operators, federal agencies, and mine workers involved. Most of the improvement has been brought about by the use of existing technology to control, suppress, and collect respirable coal mine dust. Research and development by the Bureau of Mines has contributed significantly to the accomplishment by improving the methods for sampling, control, suppression, and collection.

Jan 1, 1980

By C. V. Brennan

This paper, describing the various mining methods and practices at Britannia mines, Britannia Beach, British Columbia, is one of a series covering mining practices, methods, and costs in the mining districts of the United States and Canada. The Britannia property has been operated continuously for 30 years, and in that time many diverse methods have been used in exploiting the various types of orebodies worked. Under normal conditions mining methods include surface gloryholes, shrinkage stoping, shrinkage with powder drifts for primary breaking, horizontal cut-and-fill, horizontal and inclined square-setting, and timbered and open rills, the three latter systems being combined with close filling. The Britannia method of mining, a large-scale retreating shrinkage system usually combined with powder drifts for primary breaking, has been developed and applied here very successfully. Each block of ground as developed is studied as a separate problem, and the mining method, or combination of methods best adapted to the work in hand is applied thereto. Operating at, capacity, the series of mines produces 7,000 tons of ore per day.

Jan 1, 1935

By Richard E. Thill

The Bureau of Mines' Oil Shale Data Bank (OSDB) was created in 1976 to serve as a centralized source for the storage, retrieval, and dissemination of technical literature, patents, and information on research projects in oil shale. Thousands of bibliographic references, patents, and research projects relating to the mining of oil shale have been identified, abstracted, and indexed according to selected keyword topics. The resulting data bank listings are contained in three sections, each with a separate keyword breakdown for use in rapidly identifying references pertaining to a specific subject. All references cited in the OSDB were published prior to an established cut-off date of May 1, 1981, when a redirection of Bureau of Mines programs resulted in the loss of project funds and the subsequent phasing-out of data bank operations. ACKNOWLEDGMENTS The oil shale data bank listings are the result of a team effort of the project staff. The contributions of Jimaleen Jansma for keypunching, information acquisition, and data entry, and John Brandenburg and Sandra rake for keywording and information acquisition are gratefully acknowledged. Appreciation is expressed to the staff members of the Smithsonian Science Information Exchange, Washington D.C. for their cooperation in supplying data on recent research projects in oil shale for inclusion in the OSDR listings. Appreciation is extended also to the staff of the Gallegos Research Group for assisting with computer services to obtain the final printouts and transfer of files onto magnetic tape.

Jan 1, 1982

By F. Fraas

ELECTROSTATIC methods are used to separate and concentrate or purify granular particles derived from ores or various synthetic and agricultural products. Compared with other separation methods that require many technological refinements, the electrostatic attraction of fibers, grass, and seeds to charged surfaces clan be accomplished under the most primitive circumstances, and the early development of this method of beneficiation seemed very promising. Precise application of the method to provide high selectivity, however, is a complex procedure, and interest in this method declined. During this period Mr. O. C. Ralston initiated a Bureau of Mines research program oil electrostatic separation. It is the purpose of thins publication to describe the development of the electrostatic method of particle separation from the early beginning to the present resurgence of interest. Most of the information for this description bas been derived from references, a few of which were not available for thorough review. Much information has been drawn from the investitions of the Bureau. Acknowledgments Mr. O. C. Ralston, former Chief metallurgist of the Bureau of Mines, began the research program on the subject and did research on the mils literature. Both Mr. Ralston and Mr. H. B. Johnson, former president of the Huff Electrostatic Separator Co., furnished patent references. A critical review by Mr. F. D. Lamb, Research director, and Mr. M. J. Spendlove, Supervisory metallurgist, Bureau of Mines, College Park Metallurgy Research Center, lifts been of much value in preparing this report.

Jan 1, 1962

By H. D. Hunt

This paper which describes the milling practice of the Miami Copper Co. is one of a series being prepared by the United States Bureau of Mines. LOCATION The mine, concentrator, and other surface plants of the Miami Copper Co. are located near the town of Miami in the Globe-Miami mining district of Gila County, Ariz.

Jan 1, 1932