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By Raja V. Rarnani, Robert L. Frantz

"The Generic Mineral Technology Center for Respirable Dust (GTCRD) was created at The Pennsylvania State University and West Virginia University by a congressional initiative in 1983 responding to recommendations in the 1980 National Academy of Sciences study on the Measurement and Control of Dust in Mines. Many of these recommendations dealt with the need to initiate focused fundamental research for further professional progress in dust control. Long-term, sustained support was emphasized to develop expertise in respirable dust research. In creating this Center, Penn State and West Virginia University were specifically recognized for their expertise in and facilities for research on coal mining and medicine. Today, the Center includes the Massachusetts Institute of Technology, the University of Minnesota, and the Michigan Technology University. The Respirable Dust Center is the only organization that coordinates and integrates the medical, scientific, and engineering aspects of respirable dust disease. The Center works with the U.S. Bureau of Mines (USBM), Mine Safety and Health Administration (MSHA), the National Institute for Occupational Safety and Health (NIOSH), the United Mine Workers of America (UMWA), and the U.S. coal industry in defining the research priorities for the programs of the Center to enhance research synergism.The Center's mission is to enhance the health, safety and productivity of miners by advancing the fundamental understanding of all aspects of respirable dust associated with mining and milling and the interaction of dust and lungs to reduce the incidence and severity of respirable dust disease.All Dust Center activities are focused to be responsive to this mission, which is shared by the several federal agencies closely associated with the GTCRD. While significant progress has made mine atmospheres cleaner and healthier, respirable dust-related disease remains the nation's most pernicious industrial hazard.The goals of the GTCRD were formulated with recognition of the diverse scientific, engineering, and medical aspects of respirable dust, in addition to a need to enhance researcher interaction, as well as education and technology transfer efforts, in the respirable dust area. These goals reflect the needs of the mining industry as determined by the National Academy of Sciences Committee on Measurement and Control of Respirable Dust study done in 1980. The report of this committee encouraged the Bureau of Mines to redirect its research efforts ""...toward obtaining fundamental understanding of the origin, transport and characteristics of respirable coal mine dust."" The GTCRD's goals, detailed in chapter three of this document, were formulated to mesh with NAS recommendations."

Jan 1, 1995

By T. T. Campbell

This report describes the development of new electroplating baths from which tin-nickel alloy plate was deposited. Although tin-nickel plate can be deposited from an aqueous ammonium bifluoride bath, the corrosive nature of this bath has served as a deterrent to its use. The Bureau of Mines felt that more general acceptance of this new alloy plate would follow if neutral or alkaline baths could be developed. Promising results were obtained from electrolytes containing both tin and nickel chlorides dissolved in triethanolamine-hydrochloric acid or in ethylene glycol hydrochloric acid baths. Current efficiencies close to 100 percent were obtained with these baths. Research revealed that tin-nickel plate could be produced from organic solvents or from mixed aqueous-organic electrolytes. The composition of the alloy deposit - 65 percent tin and 35 percent nickel - was found to exhibit the same single-phase structure that is obtained from the commercially accepted fluoride-type bath.

Jan 1, 1959

By B. F. Naylor

"INTRODUCTION Investigation of the physical properties of electrolytic manganese and its alloys has constituted a part of the program of the Bureau of Mines for several years, and already extensive data have been reported. 3-14/ Heat-content measurements above 25° C. of pure manganese 15/ were completed recently at the Pacific Experiment Station of the Bureau, and the results obtained removed many of the inconsistencies in previously reported data. This paper reports heat-content data of seven manganese-copper alloys, varying in composition from 25 to 90 percent man-ganese. The alloys, obtained from the Salt Lake City Station, 16/ had been quenched from 850° C, and cold-worked. Without further heat treatment, heat-content measurements of each of these alloys were made at 100° or less temperature intervals from 450° to 850º C., as it was considered likely that any abnormal behavior of the specific heat would be found in this temperature range. Also, a portion of each alloy was heat-aged at given temperatures for periods of time thought sufficient to reach phase-equilibrium; then the heat-contents above 25° C. were determined at the aging temperatures. (Heat-aging was done at approximately 450°, 550°, 650°, 750°, and 850° C.)METHOD AND MATERIALSThe heat contents were determined by the ""drop"" method in a previously described apparatus. 17/ The calorimeter was cali-brated with electrical energy, measured in international joules, and the results were converted to the conventional thermochemical calorie by the relation, 1 cal. = 4.1833 int. joules."

Jan 1, 1946

By N. S. Dalal, B. Jafari, F. H. Y. Green, M. M. Suryan, V. Vallyathan

"Freshly ground and aged anthracite and bituminous coal samples were investigated by electron spin resonance (ESR) spectroscopy to detect the presence, concentration and reactivity of free radicals. Freshly ground anthracite coal produced greater concentration of free radicals than the bituminous coal, and the radical reactivity was also greater for the anthracite. The reactivity of the newly produced free radicals in the anthracite dust correlated with the dust's toxicity. Furthermore similar coal-based free radicals were detected in the lung tissue of autopsied coal miners, suggestive of persistent reactivity by the embedded coal dust leading to the progressive disease process. Results of the studies on the severity of coal workers' pneumoconiosis (CWP) and free radical concentration m lung tissue support this hypothesis.INTRODUCTIONCOAL WORKERS' PNEUMOCONIOSIS (CWP) has been an important topic of concern to miners, mining engineers, epidemiologists and medical researchers for decades. It is well known that the prevalence and severity of CWP differ markedly between different regions and mines despite comparable exposures to respirable dust (REISNER and RoBOCK, 1977; HURLEY et al., 1979). These variations in pathogenicity of coal mine dusts can only partially be explained by differences in the mineral composition and by rank of coal (CHRISTIAN and NELSON, 1978; CHRISTIAN et al., 1979; HATCH et al., 1980). Cytotoxity studies on mammalian cells do not correspond well with the human disease pattern (CHRISTIAN and NELSON, 1978; CHRISTIAN et al., 1979; HATCH et al.,1980; VALL YA THAN et al., 1988). For example, while epidemiological studies of coal miners (REISNER and ROBECK, 1977; HURLEY et al., 1979) indicate that the prevalence of CWP correlates roughly with the rank of coal, such correlation has not yet been established in biological studies, despite considerable effort (CHRISTIAN and NELSON, 1978; CHRISTIAN et al., 1979; HATCH et al., 1980). In order to help resolve this apparent paradox we have undertaken a systematic study to evaluate whether any correlation exists between the concentration of free radicals present in fresh or aged coal dusts from two well-characterized U.S. coals. This study was also prompted in part by observations reported in the literature that organic free radicals can be formed on the surface of freshly fractured coals (LEBEDEV et al., 1978; DULIBA and CLARKSON, 1984). In particular, ARTEMOV and REZNIK (1980) noted that the decay lifetimes and, hence, the reactivity of the organic free radicals formed on crushing Russian coals, .depended"

Jan 1, 1989

By J. B. Gayle

Numerous investigators have studied the addition of inert4 substances to coking blends. Generally, the results have yielded trends applicable only to the particular coals and inerts studied. Recently, somewhat more general results were obtained for cokes produced from blends containing added inerts, using the sole-heated oven. The present investigation represents an extension of this work to include a wider range of inerts and to determine the applicability of the various conclusions to cokes produced with the Tuscaloosa oven. The results indicated that an increase in dry-coal charge density of 1 pound per cubic foot (p.c.f.) caused a corresponding change in the hardness (1/4-inch tumbler index) of Tuscaloosa oven cokes of 0.9 percentage points. This value compares favorably with the value of 0.7 determined previously for the sole-heated oven and Bureau of Mines-American Gas Association (BM-AGA) retort.

Jan 1, 1961

By George R. Schottler

The Bureau of Mines investigated the distribution of uranium and various methods of ore sampling in a uranium deposit typical of those in the Morrison Formation sandstone of the Ambrosia Lake area, Grants mining district, north-western New Mexico. Chemical and radiometric assays of diamond-drill core samples are compared in detail by statistical techniques, and the assay data are correlated with the stratigraphy of the deposit. Conclusions applicable to ore-reserve estimation in geologically similar uranium deposits are drawn.

Jan 1, 1971

By John Taber, Robert D. O'Brien

"INTRODUCTION The Bozeman corundum deposit was first examined in May 1944 by an engineer of the Bureau of Mines. In August 1944, the property was re-examined because of a sharply increased war demand for corundum. A small program of trench exploring was undertaken after the second examination. The work was started in October 1944 and was completed in December 1944. This report presents the essential data obtained by the exploratory work.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 exploration work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests.The field work on the Bear Trap project was supervised by E. W. Newman, district engineer Montana District office. The microscopic examinations and. the grid grain-count analyses of the samples and the beneficiation tests were made at the Bureau's laboratory at Salt Lake City, Utah, under the direction of S. R. Zimmerley, chief, Salt Lake City Division, Metallurgical Branch."

May 1, 1947

By P. D. Laverty

The U.S. Bureau of Mines treated mixed and contaminated super alloy scrap by pyrometallurgical and hydrometallurgical methods to separate and recover metal values. Best results were obtained by leaching Zn-treated or atomized scrap with HCI-02 at 9SO C and 50 psig 02' This resulted in dissolving approxi-mately 98 pet of the AI, Co, Cr, Cu, Fe, Mn, Ni, and Zn while rejecting over 98 pct of the Mo, Nb, Ta, Ti, W, and Zr as an insoluble refractory residue. Chlorine was successfully substituted for HCI to leach Zn-treated scrap but was unsuccessful for leaching atomized scrap. The leaching solution was treated by pH adjustment and hydrothermal precipitation at 2000 C for 4 h to remove AI, Cr, Fe, and other contaminants as a filterable precipitate. Recovery of Co and Ni would be accomplished by solvent extraction and e1ectrowinning. Chromium recovery as a ferroalloy was demonstrated.

Jan 1, 1989

By D. G. Kuehn

Studies were conducted by the Bureau of Mines to determine the positive ions and neutral species produced in glow discharges of gas streams containing 1.0 percent NO in helium, 29 percent dry air in helium, and 1.06 percent NO in N2, Mass spectrographic measurements were conducted for gas pressures from 2.3 to 10.0 torr and dc currents from 10 to 20 mAo Ion species observed included NO+, N2 +, O2 +, N+, and 0+ with lesser amounts of He+, He2+, and N02+. Variations in various ionic and neutral species with discharge duration were interpreted to be consistent with an electrically induced dissociation of NO to produce N2 and O2. No nitrogen oxides were observed to form in glow discharges of the helium-air mixture.

Jan 1, 1975

By Richard L. Rains

The Bureau of Mines conducted a mineral investigation of the 29,000-acre Dixie Summit area near Elk City, Idaho, during the summer of 1989. At the Petsite mine a marginally economic, identified resource of 4.9 million tons with an average grade of 0.023 ounces gold per ton was delineated. Possible resources of gold, along with silver, copper, lead, and zinc, occur in at least eight other lode deposits. Placer gold may be recoverable by recreational-sized suction dredges in some stream drainages, Five lode mines in the study area have produced over 5,516 ounces of gold (placer gold production was not recorded), 4,757 troy ounces of sliver, 36,746 pounds of lead, and 3,800 pounds of copper. Current mining claims in or adjacent to the study area total 460 lode and 70 placer claims. There are two patented lode claims within the Dixie Summit study area.

Jan 1, 1991

By BUREAU OF MINES

The cheapest method of handling gravel in placer mining operations is by hydraulic mining . In working gravel deposits by hydraulic mining , it is essential that an abundant supply of water under sufficient head can be economically developed and that there is sufficient grade for sluice boxes and for disposal of the tailing . Without dumping facilities , simple hydraulic mining is an impossibility . The cost of hydraulic mining may range from 2 cents a yard under favorable condıtions to 12 or even 20 cents under less favorable conditions and to 35 cents or more a yard in Alaska , according to conditions of operation , and if frozen gravel is encountered . When it is necessary to elevate gravel , the costs may exceed 60 cents a cubic yard . When the natural conditions do not permit of hydraulic pining proper , other methods of elevating the grade are employed , some of which are described below . Bucket dredging has replaced hydraulic mining in importance in California and other states where hydraulic mining was once extensively carried on , and is by far the cheapest method of elevating gravel when mechanical methods are required and the physical conditions are suitable for dredging . Dredging costs vary greatly under the different conditions encountered , and the total amount of gold to be recovered must of course be enough to warrant the cost of a dredge installation . Gold dredging operations in the United States are fully described in Bull . 127 , U.S. Bureau of Mines .

Jan 1, 1922

By W. M. Weigel

"Sand is one of the commonest materials for industrial use, not only as a building material, but in many industrial processes. The general name applies to all grades, from the comparatively impure, unsorted product used in concrete, to especially sized products of extreme chemical purity. Various definitions have been proposed, all more or less open to objection, as they fail to cover special applications. One is: ""Sand - The fine granular material naturally or artificially produced by the disintegration or crushing of rock or slag"". This does not fit the definition of sand as understood by geologists, who consider sand only as a naturally formed product. Another is: ""Sand - The fine granular material naturally produced by the disintegration of rock"". This does not take the chemical com-position into account, and for practically all uses, except in concrete and plaster products, a material composed predominantly of silica or rather quarts is implied.Sand for special purposes usually requires different methods of preparation from those where the ordinary mixture of sizes as naturally occurring are suitable. One of the classes requiring the most uniformly sized grains is sand blast sand.Sand Blast SandThe use of the sand blast has increased rapidly during the past few years. It was formerly used almost entirely in the foundry to clean and remove inequalities from rough castings. This is still the most important application, but in addition, it is now employed for the removal of paint from old surfaces, carving and engraving on stone and marble, glass cutting, cleaning or renovating the rails of stone and brick buildings that have become discolored, preparing the surface of metals for the electrolytic bath, putting the final finish to metal surfaces, and has even been proposed as a means of channeling or cutting out blocks of stone in the quarry."

Jun 1, 1924

Develop quieted, hand-held pneumatic percussion drills that can replace standard hand-held drills in many underground mining applications. The Problem Percussion drills are the noisiest machines used in underground mines; noise levels of 115 to 120 dBA are common, requiring the use of hearing protectors and limiting the time a miner is permit-ted to operate the drill during an 8-hour shift. Hand-held pneumatic percussion drills pose a particularly difficult problem because the operator cannot be isolated from the noise source (e.g., an acoustical cab), and alternative technologies for drilling roof bolt holes and blastholes in tight quarters are not readily available.

Jan 1, 1984

By R. V. Ramani, K. V. K. Prasad

"Solution of most engineering problems requires, in addition to vast ·numerical calculations, substantial use of practical judgement and expertise. With advances in applied mathematics and computer technology, the numerical aspects of problem solution have reached a considerable level of maturity; However; it is only .recently that approaches like the expert systems methodology have been developed to ·incorporate the Judgemental aspects as well. For rapid development and prototying of expert systems, expert system building tools or ""shells"" have become widely available. For the expert system developer, identification of the key characteristics of the problem domain and selection of the right expert system tool are of crucial importance. In this paper, the important attributes required in an expert system shell for use in the development or a mine ventilation planning expert system are discussed. These attributes are general in that most engineering problems in mining would have these requirements. Also, the results of an exercise undertaken to evaluate commercially available shells for application to mining engineering problems are presented.INRODUCTIONExpert systems (ES) are interactive computer programs which use high quality specialized knowledge in some narrow problem domain to solve complex problems in that domain. These complex problems lack structured and/or standard ways of solution and involve substantial use of subjective and experience based knowledge. One of the first expert systems was MYCIN, developed in 1974, in which subjective and heuristic knowledge of expert physicians was used to diagnose infectious diseases and provide antimicrobial therapy (Buchanan arid Shortliffe, 1984). Since MYCIN, expert systems applications have appeared in other areas such as mineral prospecting (Gaschnig, 1982), configuration of computers (McDermott, 1982) and structural engineering (Bennett and Englemore, 1979)."

Jan 1, 1989

By Samuel B. Flagg

The Bureau of Mines is endeavoring to ascertain how mineral fuels in which the Government has a direct interest, by ownership or use, can be utilized with highest efficiency. For this reason the bureau has been, and is, carrying on investigations to ascertain the condi- tions of furnace construction and management that are necessary to insure the smokeless combustion of the different coals that are found in public lands or are purchased for Government ships and power plants. Another reason for the bureau undertaking these investigations is the need of better furnace management and a more careful selec- tion of fuel at many Government plants. There are Federal build- ings in hundreds of cities. The coals available at many of these cities differ greatly in quality, and the furnaces in some of the Fed- eral buildings were not designed for efficient utilization of the cheap- est available coal. Hence, some of the boiler plants smoke badly unless fed with low-volatile coal and have caused repeated com- plaints not only from neighboring property owners who have suffered damage, but from persons endeavoring to create a civic pride in clear air. In the course of its fuel investigations the bureau has noted the conditions governing fuel consumption in different cities and has studied the attempts made by these cities to abate smoke through the passage of ordinances imposing penalties on smoky stacks. Some results of that study are presented in this report. The most im- portant conclusion reached is that smoke abatement by ordinance can not hope to succeed unless supported by public sentiment and that a smoke ordinance should look to future prevention rather than to immediate prohibition. In other words, strict control of furnace construction offers much greater hope for smoke abatement than desultory imposition of severe penalties on the escape of "dense" or "black" smoke.

Jan 1, 1912

By John Ward Smith

Oil-yield data are presented for core samples from Colorado Corehole No.1, drilled by the Bureau of Mines and the Atomic Energy Commission in a previously untested oil-shale area near the northern edge of Colorado's Piceance Creek Basin. Continuous oil shale 2068 feet thick, averaging 18.41 gallons of oil per ton of shale and representing 1.8 billion barrels of oil per square mile, occurs at the core site.

Jan 1, 1968

By F. N. Kissell, C. D. Litton

This study ranks the factors impacting survival during a coal mine fire. It bas already been established that reducing time delays is the most important factor in saving lives. Consequently every event during afire is measured in terms d its duration, and the effectiveness d any action taken to improve survival is measured in terms d the time it saves. By ranking actions according to time saved these authors found that a comhination d actions was most effective. This combination was: • installing lifelines. • moderately decreasing air leakage and • decreasing the fire growth rate. Changing ventilation leakage alone was much less effective, as was altering the CO (carbon monoxide), sensor alarm threshold. These results confirm an earlier fault-tree study on escape from mine fires. The fault-tree study bad shown that, with the exception d delays, single factor changes have minimal impact. Significant reductions in fire fatalities only take place with multiple factor changes.

By R. K. Koch

The vapor pressures of liquid molybdenum and liquid zirconium were determined by the Langmuir free-evaporation method. An electron-beam furnace with a water-cooled copper crucible was used for melting. Temperature was measured with a two-color ratio pyrometer. The vapor-pressure data led to the following equations: [log p (atm) = 5.429 - 28,380 T for liquid molybdenum in the range 2,890° to 2,990° K, and log p (atm) = 6.521 - 30,940 T for liquid zirconium in the range 2,229° to 2,795° K.] Third-law evaluations of each data set gave mean heats of sublimation (298.15° K) of 157.6 ± 1.8 kcal/mole and 148.4 ± 2.4 kcal/mole for molybdenum and zirconium, respectively, where the uncertainties are two standard devia¬tions. Second-law standard heats of sublimation determined from sigma plots and tabulated enthalpies were 143.5 ± 2.7 kcal/mole and 149.2 ± 3.8 kcal/mole for molybdenum and zirconium, respectively. The better agreement in heats of sublimation for zirconium is attributed to the 566° K temperature range studied which permitted a more accurate definition of the vapor pressure curve than could be obtained from the 100° K span for molybdenum. This supposition was verified by making a sigma-prime plot which utilized solid vapor pressure data for molybdenum to extend the evaluation range by 800° K. This gave a standard heat of sublimation of 155.2 ± 1.6 kcal/mole which is in good agree¬ment with the third-law value. The plot also gave a standard entropy of sublimation (298.15° K) of 35.73 ± 0.48 eu.

Jan 1, 1968

By Paul Biggs

This report presents information on 77 waterflood projects in 31 Montana oilfields. The study shows the locations of the projects, the sources and amounts of injection water, and the results in oil produced. Waterflooding, a secondary recovery technique, began in Montana about 40 years after the initial oil discovery in 1920. Often, the difference between water disposal by injection and pressure maintenance operations is not clear. Water injected at the projects in 1973 was 157.7 million barrels. In 1973, the 31 fields having waterflood projects produced 28.3 million barrels of oil valued at $88.4 million. Both in volume and value, this represents over 80 percent of the State's 1973 oil output. The projects are making possible the recovery of additional oil, thus contributing to the conservation of oil and lessening the impact of the current oil shortage.

Jan 1, 1976

By David R. Flinn

This Bureau of Mines report describes methods to electrodeposit erosion-resistant titanium diboride coatings from molten alkali metal borate baths at 900° C. These coatings have been shown to be highly resistant to material loss during impingement with high-velocity alumina and silicon carbide powders, and they show promise as protective coatings to reduce metal loss in erosive chemical environments, such as coal gasification systems. The most erosion-resistant coatings were prepared on nickel, Inconel, and molybdenum from an electrolyte containing LiBO2, NaBO2, Na2Ti03, and TiO2. The best coatings were deposited at current densities of [~]20 ma/cm2, using titanium or titanium diboride anodes. Erosion-resistant coatings were shown to exhibit (1) a high degree of crystallographic orientation along the (100) or (110) planes, (2) a chromium impurity level of less than 3 pct, and (3) a uniform, smooth, consolidated surface appearance when viewed under a microscope or by scanning electron microscopy. Optical spectroscopic studies of the molten electrolyte suggest that the lower valent (+3) titanium ion predominates in the baths.

Jan 1, 1979