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By J. A. Ruppert

The Bureau of Mines investigated methods of refining iron-contaminated zinc to marketable quality and developed a laboratory-scale process in which aluminum, added as a refining agent, reacted with the iron, forming solid Fe2Al which floated to the surface of the melt. Solids were separated by both filtration and centrifugation, using a unique type of "dipping" centrifuge devised during the work. Typical zinc recovery was 95 percent, and iron content of the metal was lowered from 0.37 to 0.02 percent.

Jan 1, 1967

By C. D. Litton

This Bureau of Mines report presents a set of guidelines for determining the distribution of product-of-combustion fire sensors in underground mines. Sensor spacing is defined in terms of sensor alarm threshold, ventilation flow rate, and mine entry dimensions. Sensor spacing guidelines are presented for detection of fires from two primary combustibles, coal and wood, which are common to the majority of underground mines. The guidelines are based on data from full-scale and intermediate-scale fire tests conducted by the Bureau of Mines.

Jan 1, 1983

By G. B. Sonneman

This final report summarizes the work done by The Bendix Corporation, Environmental Science Division, under contract to the Bureau of Mines to design, develop and test two improved systems for remote sampling the air at the working face of a coal mine in conjunction with approved portable methane detectors and machine-mounted methane monitors respectively. The work was started in May 1973 with preliminary design studies and was completed in May 1975. Five portable and two machine-mounted sampling systems were delivered. Contract "add-on" requirements for (1) modification of the machine-mounted system to accommodate a flame safety lamp and (2) a study of sensor response time improvement for the machine-mounted system were also completed.

Jan 1, 1975

By E. T. Bowers

The Accident Analysis (ADA) computer program was developed at the Spokane Research Center (SRC) to provide a rapid broad-based analysis of mining accidents. Because the Bureau of Mines often needs this type of information for the development of viable research programs the ADA program was written to access and analyze accident data available frog the Labor Department's Mine Safety and Health Administration (MSHA). This report describes the ADA program, the data it uses, and the potential value it has for planning mining research.

Jan 1, 1987

This Bureau of Mines investigation addressed two primary issues of air velocity measurement in mines: the determination and use of correction factors, and the development of guidelines for the selection of a suitable site at which the measurements should be taken. Other facets of the investigation included a comparison of measurement methods and devices, and aircourse cross-sectional area measurement. The study consisted of theoretical, laboratory, and in-mine investigations. The measurement devices included in the experimental phase were vane anemometer, vortex shedding anemometer, a prototype thermoan-emometer, smoke tube, and oil of wintergreen sprayer. The measurement methods included single-point centerline, timed-point traverse, continuous traverse for the anemometers, and various distances and cloud positions for the smoke tube and oil of wintergreen devices. The study resulted in guidelines for measurement site selection that are applicable to most inmine situations. It also showed that the use of correction factors is problematic. There are many potential pit-falls and there are cogent arguments against using certain correction factors. However, generalized correction factors were developed that can be successfully applied in routine ventilation work, provided that their use is properly understood.

Jan 1, 1985

By Frank L. Hess

Vanadium, although widely spread in minute quantities through the crust of the earth, is found in few places sufficiently concentrated to be economically mined and prepared for use. Most rocks carry from a trace to a few hundredths of a per cent of vanadium oxide, and coal ash may carry about as much as the rocks, Much of the "coal" quoted in the literature as carrying vanadium has been asphaltite, and in other ccal the vanadium is of late introduction. The ash of the petroleums, though usually present in very small quantity, may carry a large percentage of vanadiun, so that production of vanadium from it has been seriously considered. Naturally the ashes of soze asphaltites similarly carry vanadium.' The great deposit at Minasragra, Peru, to which further reference will be made, is probably an altered asphaltite. Ilmenite and cther iron minerals usually carry vanadium 10 and some has been saved from the minette ores of France. 11 Many veins that carry lead copper and zinc minerals also carry a little vanadium, which, especially if the veins are in a comparatively dry region, such as the southwestern United States, northern Mexico, Northern Rhodesia, Southwest Africa, or Spain, collects in the oxidized parts of the veins as vanadinite,

Apr 1, 1932

By Seth C. Scharfer

"As part of the Bureau of Mines effort to provide thermodynamic data for the advancement of mineral technology, the Gibbs energies of formation of MoS2 (molybdenite) and WS2 (tungsten disulfide) were determined with high-temperature galvanic cells employing stabilized Zr02 (zirconia) as the electro¬lyte. In the temperature range from 867 to 1,209 K, potential measurements were obtained for the cellPt, MoS2 , Mo02 , SO2 = 1 atm // Zr02 // 02 = 0.0112 atm, Pt, with the overall cell reactionMoS2(c) + 3 02(g, 0.0112 atm) = Mo02 (c) + 2 S02(g). (1)These results, combined with the best available values for Gibbs energies of formation (?G°f) of Mo02 (molybdenum dioxide) and SO2 (sulfur dioxide) from the literature, give the standard Gibbs energy of formation of MoS2, ?G°f, for the reactionMo(c) + S2(g) = MoS2(c) (2)?G°f = -96.681 + 43.76 x 10-3T±0.538 kcal/mole, (3)where temperature (T) is expressed in Kelvins.Similar measurements in the temperature range from 872 to 1,210 K were obtained for the cellPt, WS2 , W03 , SO2 = 1 atm // Zr02 // 02 = 0.0114 atm, Pt, with the overall cell reactionWS2(c) + 3.5 02(g, 0.0114 atm) = W03 (c)+ 2 S02(g). (4) Combination of these results with the best available data of ?G°f for W03 (tungsten trioxide) and SO2 from the literature gives the Gibbs energy of formation of WS2 in the temperature range from 872 to 1,210 K for the reactionW(c) + S2(g) = WS2 (c)(5)?G°f = -92.429 + 43.88 x 10-3T ± 0.280 kcal/mole. (6)A third-law analysis yields a standard enthalpy (?H°f) for the reaction298Mo(c) + 2 S(rh) = MoS2(c), (7)?H°f = -67.36±0.60 kcal/mole, (8)298where the standard states are pure crystalline MoS2 / and rhombic sulfur."

Jan 1, 1980

By V. A. Marple, K. L. Rubow, S. M. Behm

"An eight-stage cascade impactor, with cut-sizes ranging from 0.056 to 18 um at a flow rate of 30 L/min, has been developed, calibrated, and tested in field programs. This impactor, called a microorifice uniform deposit impactor, has several features not normally found in cascade impactors. Ultrafine particles as small as 0.056 um are collected while keeping the pressure drop moderate by utilizing multiple nozzles (up to 2000) as small as 52 um in diameter. At each stage the collected particles are deposited uniformly over the entire impaction plate by rotating the impaction plate relative to the nozzles and by the correct radial placement of the nozzles. The particle cutoff characteristics (collection efficiency curves) of each stage and inter-stage losses were determined by means of monodisperse aerosols. The cutoff characteristics were found to be sharp and similar for all stages.Inertial impactors are widely used for the size-selective collection of aerosol particles. One reason for their wide usage is that the principle of operation is simple: a jet of particle-laden air is directed at a flat impaction plate. Large particles are collected on the plate while smaller particles follow the airflow out of the impaction region and are not collected. The division between the size of particles collected and those that are not is quite sharp. Secondly, the particles in an impactor are classified by their aerodynamic diameter (an important size parameter in many fields of study, including those related to respirable particle health effects). Thirdly, it is easy to collect particles in discrete size ranges by passing the aerosol through a number of stages (one stage consisting of a nozzle and impaction plae) in series, with each subsequent stage collecting particles smaller than the one before it. This is known as a cascade impactor. Finally, impactors can classify particles over a wide range of particle sizes: as low as 0.005 um (Fernandez de la Mora et al., 1990) and as large as approximately 50 um (Vanderpool et al., 1987).This paper describes a general purpose cascade impactor that has been developed in our laboratory and used in a variety of studies including visibility studies (McMurry et al., 1986; McMurry and Zhang, 1989), underground mine studies (Marple et al., 1986; Rubow and Marple, 1988; Rubow et al., 1988), and general atmospheric pollution studies (Macias et al., 1981; Dzubay et al., 1984). The impactor, called a microorifice uniform deposit impactor (MOUDI model 100, MSP Corp., Minneapolis, Minn.), is the integration of two earlier impactor de¬velopments: the microorifice impactor (M01) (Kuhlmey et al., 1981) and the uniform deposit impactor (UDI) (Marple et al., 1981).The MOUDI has several features normally not found in other cascade impactors. These include collection of particles as small as 0.056 um in aerodynamic diameter with a moderate pressure drop, uniform particle collection on the impaction plates, inter-changeable impaction plates to allow for the plates to be easily and quickly changed in the field, and covers for these substrates to provide a means for safe storage and/or transport of the collected particles to the laboratory for analysis."

Mar 1, 1992

By J. A. CoRGAN, J. A. DECARLO

The coal -carbonizing industry is recognized as one of our country's most essential industries , and this position has been achieved through its primary function as a source of supply of special fuels and chemical raw materials . When coal is carbonized at high temperatures in slot - type coke ovens in the absence of air , it decomposes into two main products cokę ... and crude gas . Of these , the more important is coke , a hard, strong, porous solid that remains in the oven after the volatile matter in the coal has been driven out by heat . The hot crude gas carries with it all. of the coke -plant products except coke and has a complex composition in the vapor: state . Its processing , to produce the four principal coproducts of coke (tar , ammonia , light oil, and gas ) , is accomplished by preferential condensation and absorption . Although the principal coproducts of coke tar , ammonia , and crude light oil - - gas, are of secondary importance , their

Jun 1, 1949

By Sidney Katell

This report covers the period January 1963 through December 1963; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the fifth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facets of cost engineering in the field of chemical and petroleum plants and related subjects, are from the following sources: 1. American Association of Cost Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress. 6. Chemical Week. 7. Coal Age. 8. Coal--Today and Tomorrow. 9. Coal Utilization. 3/ 10. Cost Engineering. 11. Hydrocarbon Processing and Petroleum Refiner. 12. Industrial and Engineering Chemistry. 13. Nucleonics. 14. Oil and Gas Journal. 15. Petroleum Management. 16. World Oil.

Jan 1, 1964

By Sidney Katell

This report covers the period January 1963 through December 1963; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the fifth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facets of cost engineering in the field of chemical and petroleum plants and related subjects, are from the following sources:

Jan 1, 1964

By David H. Yee

Because of environmental concerns, the Bureau of Mines investigated an anhydrous chlorination process for the recovery of copper from chalcopyrite, Pelletized concentrate was reacted continuously with chlorine in a vertical shaft reactor at 550° to 750° C to extract copper-iron chlorides and elemental sulfur. The resulting molten metal chlorides drained from the reactor and collected in a receiver while sulfur distilled from the top and condensed in a separate unit. The tests were conducted in a 10-cm-diam reactor constructed of glass and in l5-cm-diam reactors constructed from various refractory materials. A high-alumina ramming mix exhibited the best resistance to molten metal chlorides and elemental sulfur in chlorine atmospheres. A reactor made with this high-alumina refractory was operated for 55 hr under actual chlorinating conditions without suffering any deterioration. Tests results show that more than 96 pct of the chalcopyrite was converted to copper-iron chlorides and elemental sulfur. Good separation of the metal chloride and sulfur products was achieved. After filtration, elemental sulfur of greater than 99 pct purity was obtained.

Jan 1, 1977

Commodities statistics and otter information are available through the following t et systems: Internet Access: To acccess the USBM Gopher server on Internet, connect to: gopher.usbm.gov port 70, using gopher client software. Or contact the Systems Administrator for technical questions: Matt Klevemann, 412-892-6499 (klevemmc@miner.usbm.gov) These USBM materials are available on Internet, with more to come in the future: Publications and other research findings, including this bimonthly publications list, newsletters, tech transfer updates, enviromental technology research, health and safety information. USBM software products Media materials and speeches. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. Mines FaxBack: Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219-3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button on your fax machine.

Jan 1, 1995

By H. J. Lechtenberg

This Bureau of Mines report investigates solvent injection as a means of increasing oil production from low-gravity oilfields; thus, wells in two California oilfields that produce from reservoirs having low-gravity oil were injected with highly aromatic solvents to increase their oil recovery. The wells were either allowed to soak or the solvent was circulated for a period of time. In some of the wells, the solvent was followed by a slug of water. The post-stimulation production rate was considerably higher than the prestimulation rate of the wells. Wells in which the solvent was not followed by water showed an immediate increase in oil production, and essentially all of the solvent was recovered. The wells in which solvent was followed by water essentially showed a delay in the increase in oil production, thus indicating a temporary water block. The results show that the production rate is usually increased by the injection of solvent, and the method may prevent early abandonment of marginal producers. Cumulative post-stimulation oil production indicates that cyclic solvent injection treatment can be an economic success.

Jan 1, 1974

By P. J. Coleman

Research in the field of mining safety and health in the United States plays an important part in protecting the lives of miners. The National Institute for Occupational Safety and Health (NIOSH) Mining Program conducts surveillance, studies and developmental work aimed at improving the safety and health of miners. With recent reviews of the Mining Program by the National Academy of Sciences and the Mining Program response (NIOSH, 2008), the importance of setting goals, conducting high quality engineering and scientific research and evaluating the outputs, outcomes, relevance and impacts of these projects has been reemphasized. Surveillance of reported injuries is a first step in deciding on research directions and in designing specific projects. Groups of injuries often share features and attributes that suggest common causes and may respond to similar preventive efforts. Identifying groups of injuries also serves to prioritize intervention efforts. The Mine Safety and Health Administration (MSHA) Accident and Injury database (MSHA, 2008) provides individual case reports of mining injuries, illnesses and certain no-injury accidents (events such as roof falls that stop mine production or miners? activities for more than one hour). This database is an indispensable resource for researchers and stakeholders needing information on the statistics of these events. From an epidemiological perspective, research projects target groups of miners at risk due to specific patterns of work, equipment, mine settings and the management of safety and health in their mines. Incidence rates are provided by the MSHA data for selected variables, such as surface/underground location, standard industrial classification and state. While incidence rates are the preferred measure for all variables, denominators are not typically available; for example, to more clearly under-stand the data about injury by occupational type, it would be necessary to conduct demographic surveys. A current survey of the demographics of the mining industry should be complete by 2010, which will allow incidence rates to be developed for a number of variables such as age, occupation and experience. This survey will provide the first update of its kind since the first survey was conducted in 1985.

Jan 1, 2010

By O. M. Bishop

From October 1943 to March 1944, the Bureau of Mines conducted core drilling at the Victory fluorspar mine, Hardin County, Ill. to test the Fredonia limestone and the included sub-Rosiclare sandstone zone beneath the existing stopes. Twenty-one vertical holes were drilled to an average depth of 60 feet. Ore was penetrated in six holes. Since its discovery in 1927, the Victory mine has produced approximately 5 percent of the total fluorspar mined in the United states after that date. The ore discovered in the early mine development is now exhausted, except that contained in pillars drifting to the northeast has partly developed one substantial ore body, and company drilling has indicated another nearby. The increasing need for fluorite for war use in 1943 suggested the desirability of mining the pillars, provided it could be established that no ore beds existed below the stopes or in areas to which access would be obtained through the present workings. This work describes the work accomplished during the project and presents the data obtained.

Jan 1, 1948

By John Ward Smith

Aragonite, co-occurring with calcite and dolomite as matrix minerals, has been discovered in Mahogany zone oil shales of Colorado's Eocene Green River Formation, posing puzzles on the geochemical patterns of their separate origins, reasons for their simultaneous existence, and their interrelation. The presence of aragonite is demonstrated by X-ray diffraction. Amounts of aragonite and dolomite are significantly and inversely related, but the calcite quantity is essentially independent of either aragonite or dolomite quantity. A geochemical pattern outlining the deposition conditions that created the Green River Formation oil shale is postulated from characteristics of the oil shale. The development of the three separate carbonates--aragonite, calcite, and dolomite--the inverse relationship between aragonite and dolomite, and the independence of amounts of calcite and the other two carbonates are shown to be natural consequences of this oil-shale genesis pattern.

Jan 1, 1973

By R. E. Heithecker, Van A. Mills

"Crude oils are capable of dissolving quantities of gas under pressure. This fact has been known for some time, but questions have arisen as to the effects of gas in solution upon the characteristics of the oil. Previous investigations4 show that gas in solution in an oil affects the viscosity and surface tension of the oil, but the effects on the volume and A. P. I. gravity of the oil have not been known. The results given in this report show that there is a decided change both in volume and in the A. P. I. gravity of the oil due to the solution of the gas in the oil under pressure. As gas is dissolved, the volume of the oil and the A. P. I. gravity increase. The converse of this phenomenon is also true: if the gas is released from a saturated oil, there is a shrinkage in volume and a decrease in A.P.I. gravity due to the release of gas from solution. However, various oils show marked tendencies to retain a portion of the dissolved gas upon releasing the pressure to that of the atmosphere. This retained gas has an appreciable effect on the volume and A. P. I. gravity of the oil because the oil does not resume its initial volume or gravity while it retains dissolved gas. In a sense the oil has been ""freshened"" and will not return to its original or weathered volume until it loses some of the lighter fractions. Wiggins5 has shown that a fresh oil decreases both in volume and in gravity because of the weathering of the lighter fractions while the oil is standing in storage tanks.This paper includes data attained during the determination of volume and gravity correction factors to be applied in the oil recovery investigations of the Bureau of Mines. Three oils having a wide range in gravity were used in determining the correction factors. These oils were from the Bartlesville-Dewey field, Oklahoma, the Seminole field, Oklahoma, and the Inglewood field, California. The same gas that was used in the oil recovery experiments was used throughout this investigation. Determinations were made of the volume and A.P.I. gravity increases resulting from the gas going into solution at 200, 400, 600, 800, and 1,000 pounds pressure; also the increases in the volume and gravity of the oil due to retained gas were determined after the dissolved gas was liberated from solution by releasing the pressure to that of the atmosphere.Samples of residual and liberated gas were taken throughout the investigation in order to study the selective absorption and selective retention by the oil of the various constituents of the gas. The analyses of these gas samples showed that there was selective absorption and selective retention of the constituents of the gas. The tests on Inglewood crude gave the most pronounced example of selective absorption and selective retention of the gas.All of the tests were conducted at a constant temperature of 709F."

Oct 1, 1928

By Hillary W. St. Clair

This report gives the results of an experimental study of the progressive changes that occur in particle size and size distribution when a homogeneous and isotropic mineral is subjected to crushing by impact. The mineral used in the study was uniformly sized quartz, which was crushed in a simple drop¬-weight machine that applied impact energy up to about 100 kg-cm per g. Screen analyses of the crushed products were analyzed by the method of moments to determine the mean size, variance, skewness, and kurtosis. Analysis of the data from these experiments shows that the mean size of the crushed product is a function of the energy input and the initial size. The size distribution is functionally related to the degree of size reduction. As the mean particle size is decreased, at first there is a corresponding increase in the variance and decrease in the skewness, But, as size reduction is carried further, each tends eventually to approach a steady value, and the form of the size distribution becomes stable.

Jan 1, 1972

By Oliver Bowles

Slate possesses many admirable qualities, not only as a roofing material, but for blackboards, electrical switch boards, and for various structural uses such as stair trends, floor tile, baseboards, and sanitary enclosures. The American slate industry was established manor years ago, and has made remarkable progress, particularly during the past five years. One of the chief drawbacks to more rapid expansion is the high percentage of waste which reaches 75 to 94 per cent of gross production. Much of this waste is duo to rock imperfections over which man has no control, but a careful study of tae industry by the Bureau of Mines over a period of years indicates that an undesirably large percentage of the marketable slate is wasted in the processes of quarrying and manufacture. The initial step in quarrying slate is to separate from the solid ledge masses of a size that ray be conveniently removed from the quarry. This first step entails a greater waste of material than any subsequent process, and, therefore, invites the most earnest effort toward waste reduction. Attention has consequently been directed toward possible improvements in methods of making primary cuts in the quarry floor. A study of European practice with the wire saw, together with theoretical consideration of its advantages, convinced the writer that it possessed sufficient merit to justify its use as a primary slate cutter in American quarries. No practical conclusion in this matter could be reached except by experiment. Therefore, the desirability of obtaining equipment and trying it out under actual conditions of operation was urged upon operators. While no doubt the equipment could be readily manufactured in America, it had already been developed to the point of practical use in Europe; therefore the writer urged the desirability of purchasing one completely equipped wire saw in Europe, and determining through tests whether it gave sufficient promise of success to warrant its manufacture in America.

Jan 1, 1927