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By R. Unger, L. Mallett

The use of virtual reality (VR) technologies to train miners is an evolving area in research and development. In July 2006, representatives of 14 international organizations met to discuss current VR-related efforts and explore ways to employ VR in the future. This paper gives an overview of the various approaches presented at the meeting and discusses directions for future implementation. An example of a training package that teaches mine map-reading skills is presented. The meeting was the first step to building collaborations for furthering VR applications for mining. Planning has begun for a 2008 meeting open to broader participation. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.

By Ted C. Briggs

A removable-jacket distortion apparatus was constructed and used to measure distortion coefficients for two high-pressure vessels. The measured distortion coefficients were used to compute distortion coefficients for volumes VI and (V1+V2) of a 1,000-atmosphere Burnett compressibility apparatus for the temperature range 0° to 75° C. Young?s modulus for Armco 17-4 PH stainless steel, heat treated to condition H1150-M, was computed from experimentally determined distortion coefficients. A 10-to 14-percent correction to the values obtained for Young's modulus may be required because pressure vessel end effects were neglected. The distortion coefficients of the compressibility apparatus are believed to be accurate to about 1 percent.

Jan 1, 1970

By Francis Crowley

Elementary concepts of seismic wave properties are reviewed to establish a framework for discussing seismic noise and its suppression. A liberal number of references is included for those who wish to pursue the topic in detail. A base motion noise level is established for a single surface seismometer. It is argued that simple array processing and seismometer burial should regularly permit us to approach this base noise level which is found in areas free of conspicuous man-made seismic noise sources. The sensitivity of the base seismic level to a number of common disturbances is presented. Solutions that promise to hold the "effective" seismic noise at a site near the base level are given for acoustic, meteorological and fixed local surface sources. Guidelines are suggested for controlling other local man-made sources, e.g. vehicular traffic, by keeping them at sufficiently large distances away from the seismometers to keep noise at permissible levels. These guidelines are speculative and conservative. They should be the subject of future study. The ability to process against general local activity, drilling, and intra- mine sources is limited. Certainly no dramatic gain is to be expected. When strong man-made and/or intramine noise sources are not controllable, detection may well be impossible to achieve, unless the seismometer can be moved close enough to the suspected miner position, i.e. via very deep holes, to compensate for the likely vast differences in strength of the miner signal and the uncontrollable man-made noise sources. However, many intramine sources, e.g., falling water, rock bursts, explosions, etc., may well preclude the existence of a hale miner in their vicinity, and therefore any need to attempt detection of a miner at such locations. The following recommendations are made to enhance the detection and location of a miner signaling seismically. They are: 1. Seismometer burial in slim holes. 2. Narrow band detection, using multiple narrow band filters to cover the likely signal band. 3. Broadband recording and analysis for time-of-arrival estimation.

Jan 1, 1974

By H. P. Rue

The Bureau of Mines has recently collected two samples of crude oil from wells in the Greasewood Flat, area of northeastern Colorado. Sample 31310 was taken from the Continental Oi1 Co.'s well Briggs No. 1 which came in on September 27,7.931, with a maximum production of 940 barrels per day. Sample 31311 was taken from the Reiter-Foster Oil Co.'s well Ida Johnson No. 1 which came in on August 24, 1931 with a maximum production of approximately 1000 barrels per day. These two samples of crude oil are typical "intermediate base" crude oils according to the classification defined by Smith and Lane. The characteristics of these two samples, as shown by the Hempel analyses, indicate that they are almost identical. They have a very low sulphur content, and the residuum has a low carbon-residue content which would indicate that they are excellent crude oils for refining. Crude oils yielding a residuum which has a carbon-residue content of 4 per cent or less usually make good material for the manufacture of cylinder stocks. The pour points of the samples and the cloud test of the fractions obtained from the vacuum distillation indicate that the Greasewood Flat oil contains considerable wax. The high wax content would cause some difficulty in transmitting this oil through a pipe fine during extreme cold weather.

Jan 1, 1932

By Douglas Pollock, John Organiscak

Water spray characteristics, including droplet size and velocity, airborne dust capture potential, and induced airflow quantity for various spray nozzle designs were evaluated to provide basic information for improving spray applications. Water droplet size and velocity characteristics were initially measured by a Phase Doppler Particle Analyzer (PDPA) for hollow cone, full cone, flat fan, and air atomized spray nozzles at similar operating parameters. Airflow inducement and dust capture experiments were also conducted under the same operating parameters to examine any salient features of the spray nozzle type, droplet characteristics, induced airflow, and airborne dust capture. Test results indicate that there are trade offs between airflow inducement and dust capture efficiency. A spray nozzle with a wider discharge angle was observed to induce more airflow, but at reduced dust capture efficiencies. Increasing spray nozzle fluid pressure(s) generally reduced water droplet sizes with concurrent increases in droplet velocity, airflow inducement, and airborne dust capture. Placing a three-sided barrier around the spray nozzles normally reduced spray air induction and increased dust capture efficiency. A direct relationship between airborne dust capture efficiency and spray input power normalized per unit of airflow induced was ob- served. This information can be utilized to improve the performance of water sprays for reducing airborne dust levels.

By E. Chin

Natural gas was the only economically significant mineral produced. A significant amount of the gas output was consumed in the production of nitrogen fertilizer and electric power. Proved reserves of natural gas were abundant and at least sufficient to supply most of the country's industrial and domestic needs for many decades to come. Other mineral production was of little importance to the Bangladesh economy, although there were prospects for developing some of the nonmetallic minerals. The flat river-delta terrain comprising nearly all of Bangladesh made the potential for discovering major, economically exploitable mineral deposits poor. The deep sediments, however, have good potential for crude oil or additional natural gas discoveries.

Jan 1, 1985

By Jack C. White

The purpose of this Bureau of Mines work was to develop information useful in improving copper recovery during copper milling operations. Eleven copper mill tailings from the Western United States were subjected to froth flotation and cyanide leaching to provide an experimental basis for comparing their beneficiation response. Recoveries in flotation concentrates made from mill tailings ranged from 65 to 15 percent, at copper grades of 13 and 2.2 percent, respectively. Liberated copper sulfide minerals present in two samples were readily recovered by laboratory froth flotation. Nine of the samples were less amenable to froth flotation because of physical locking between copper sulfide minerals and gangue. Correlations among tailings indicated that recovery of sulfide copper by flotation was directly related to the sulfide copper content. Empirical equations derived from flotation data provided average values for unrecoverable copper and for recovery efficiency. Flotation response of copper mill tailings may be predicted from the equations. Data from cyanide leaching provides an equation describing the limiting high values for removal of copper by this method.

Jan 1, 1974

By A. F. Colombo

The differences in starch demands that occur between ore types subjected to the anionic flotation of calcium-activated gangue and the range of residual starch contents expected to give the best metallurgical response were evaluated on a batch and pilot plant basis. A phenol-sulfuric acid procedure was used to determine the residual starch contents in the iron ore slurries. Three pilot plant campaigns on samples from a group of orebodies located on the Marquette Range, Michigan, showed that in the rougher flotation pulp, a residual carbohydrate range of 25 to 100 ppm, which is equivalent to a 0.5 lb/short ton spread, yielded optimum results. Concentrates assaying at least 65 percent Fe and less than 6.0 percent Si02 and containing more than 80 per-cent of the recoverable iron were obtained. Both batch and continuous research indicated that starch adsorption is calcium modulated and relatively unaffected by the fatty acid additions employed. Residual starch level is not a critical control factor, but the addition must be adjusted to about 25 to 50 ppm residual starch and kept in this range for most effective utilization of the added tapioca flour.

Jan 1, 1972

By L. R. Burdick

The Smokescope is an instrument recently developed for determining the density of smoke by shade comparison. The instrument is designed so that the smoke is seen adjacent to two shades of gray corresponding to Nos. 2 and 3 on the Ringelmann chart. Data on smoke density are important in the smoke-abatement field. The method that is specified and accepted as standard for smoke-density determination by the majority of city smoke regulations involves comparing the smoke shade with the four shades on the Ringelmann chart as published by the Bureau of Mines.2/ This investigation was made to determine the accuracy and convenience of the Smokescope. It was conducted as a part of the Bureau I s air-pollution work, which includes the study of techniques that will promote smoke abatement. The accuracy of the Smokescope was arbitrarily defined as the difference between the Smokescope determinations and the determinations by the accepted, standard method and was expressed as Smokescope correction. Although the corrections obtained were strictly correct only for the two observers and the Smokescope of the investigation, they indicate what might be expected from any observer who uses a Smokescope with reference shades that duplicate those of the test instrument. The report is devoted largely to the data on Smokescope correction, which were taken from a single stack under controlled smoke conditions. Field work, which was done at various locations with different stacks, is mentioned briefly in connection with the comparison of the convenience of the two methods. The data for estimating Smokescope correction were taken for the three variables that were expected to affect the results, namely, the density of the smoke, the amount of light, and the color of the sky behind the smoke.

Jan 1, 1955

By R. A. Guidotti

The Federal Bureau of Mines has studied the reaction of oxides of columbium, vanadium, and tantalum with ammonia in vertical, gas-solids reactors at temperatures ranging from 300° to 1,300° C with the goal of preparing nitride intermediates for subsequent preparation of the metals by a thermal-decomposition step. The best nitride conversions were obtained in nonmetal reactors. With Cb205, V2O3, and V205 , low-temperature maxima in reaction rates occurred at 800°,800°, and 450° C, respectively, during oxynitride formation (in A1203) at 1 atm of pure ammonia. Conversion of the oxynitride, in a second step, to the mononitride was optimum at 1,200° C for columbium and 1,050° C for vanadium. In the case of Ta205, the rate of reaction to form Ta3N5 (in a single step) was highest at 900° C, where the presence of up to 5 percent methane was found to be beneficial; improved results were obtained by conducting the nitriding in a rotary kiln. Optimum space velocities (in the vertical Al203 reactor) ranged from 5,280 hr-1 for Cba205 to 7,950 hr-1 for V203. Oxide particle size had little effect upon reaction rates. Under fully optimized conditions, products containing less than 1 percent oxygen were readily obtained in under 6 hours.

Jan 1, 1975

By Bruce D. Sartwell

The Bureau of Mines is using characteristic X-rays produced by proton bombardment of a solid surface to provide quantitative compositional analyses of surface layers of metals. An integral X-ray yield equation has been developed that quantitatively relates the measured X-ray yield to the thickness of thin films ranging from less than a monolayer to several thousand angstroms. The use of the integral yield equation is demonstrated for the growth of a thin film by vacuum evaporation. Results are presented that show haw proton-induced X-ray emission (PIXE) has been used to determine the oxidation kinetics of iron that had been implanted with several different species of heavy ions. The sensitivity of PIXE for the measurement of very-thin-film growth kinetics is demonstrated from studies of the effect of fractional mono-layer coverages of sulfur on the initial oxidation kinetics of iron. Results are also presented in which PIXE has been used to study the redistribution of alloying elements in components of a gas turbine that had fractured due to corrosion fatigue. By combining PIXE with low-energy ion sputtering, quantitative composition depth profiles of surface layers are obtained. Examples are presented for the profiling of iron samples implanted with 25-kev nickel ions and for a platinum coating on an Fe-5Cr substrate.

Jan 1, 1980

By P. W. Jerant

The methane emissions from an advancing coal mine section were continuously monitored for 120 days. During this time, the section advanced 2,000 feet into virgin Pittsburgh coalbed producing 54,565 tons of coal with a total methane emission of 91 million ft3. Analysis of the data gathered showed that daily methane emissions did not correlate with overburden thickness and daily coal production. A good correlation was found between the daily methane emission and the average length of rib exposed to virgin coal.

Jan 1, 1976

By Greenwald, H. P

The Bureau of Mines has been conducting experiments on the explosibility of coal-dust in the experimental mine for more than 17 years. The results have been published from time to time3, and a forthcoming technical paper4 will summarize the results and discuss them in some detail. The present paper will be limited to a statement of the more important facts that these researches have discovered.

Apr 1, 1929

By Alan R. Buehler

A mineral survey of the 20,792-acre Sand Butte WSA (Wilderness study Area), ID-57-8, was conducted by U.S. Bureau of Mines personnel in 1985, at the request of the Bureau of Land Management. The WSA is in Lincoln County, south-central Idaho, about 15 miles south-southeast of Carey. There are no mines, prospects, or claims within the WSA. Basaltic lava is the only rock type exposed within the WSA. The only mineral resource is a few tons of a platy variety of lava (slab pahoehoe) which is suitable for use as decorative stone. Similar slab pahoehoe, produced from other lava fields in southern Idaho, retails for approximately $125/ton. The deposit in the WSA is too small to be mined commercially but may have value to consumers who gather their own decorative stone. INTRODUCTION A mineral survey of the Sand Butte WSA (Wilderness Study Area) 1/ was conducted in June 1985 by the USBM (U.S. Bureau of Mines) and the USGS (U.S. Geological Survey) at the request of the BLM (U.S. Bureau of Land Management). The USBM examines individual mines, prospects, claims, and mineralized zones, and evaluates identified mineral and energy resources. The USGS evaluates potential for undiscovered resources based on areal geological, geochemical, and geophysical surveys. Results of the investigations will he used to help determine the suitability of the WSA for inclusion into the National Wilderness Preservation System. The immediate goal of this and other USBM mineral surveys is to provide data to the President, Congress, government agencies, and the public for land-use decisions. The long-term objective is to ensure the Nation has an adequate and dependable supply of minerals at a reasonable cost.

Jan 1, 1986

Graduate education is an integral part of the Center's research program. The scope of. work and the duration of each research project is calculated, in part, by taking into consideration the needs of the graduate research program and graduate training. Full development of student involvement, as demonstrated by the research practicum which is offered to qualified senior undergraduates at Penn State University and is designed to acquaint them with research methods and techniques and inform them of the opportunities available in this field. and the fulfillment of graduate program requirements are of the utmost concern. The Pennsylvania State University and West Virginia University have accredited mining engineering curricula and rank among the schools with the largest enrollment in this area in the nation. The number of undergraduate students enrolled in mining engineering at Penn State and West Virginia University account for nearly 20%, of the total undergraduate enrollment in this discipline in schools across the United States. The Pennsylvania State University. West Virginia University, Massachusetts Institute of Technology, University of Minnesota, and Michigan Technological University, have granted a total of thirty-five (35) doctorate and masters degrees which can be directly attributed to research conducted in the Center.' Of these graduates, fifteen(15) have found employment in the mineral sector of the economy, i.e., in private industry, with government agencies, and at various universities, worldwide. In addition, a number of those graduating with masters degrees are currently pursuing a doctorate degree.

Aug 31, 1989

By J. D. Noll

The Mine Safety and Health Administration (MSHA) has promulgated rules to limit the exposure of metal/nonmetal underground miners to diesel particulate matter (DPM). These rules have resulted in many types of control tech­nologies being implemented including diesel particulate filters (DPF). The passive type DPF is the most desirable because it requires little maintenance and it regenerates while the vehicle is operating. One problem with passive DPFs is that many vehicles cannot develop the sustained exhaust temperatures needed to initiate DPF regeneration, and thus it is required that the DPF be catalyzed to decrease the temperature needed for regeneration. In some past studies, such catalyzed filters have been shown to cause an increase in the nitrogen dioxide concentrations in the exhaust, resulting in a potential health hazard. In this study, a lightly catalyzed DPF along with a fuel-born catalyst were employed to help reduce the DPM emissions from a 980F loader used for cleanup in a stone mine. After 30 days of use, the filter continued to regenerate successfully at the exhaust temperatures generated by this loader, substantially reduced DPM concentrations emitted in the exhaust, and did not cause a measurable increase in nitrogen dioxide levels that could be attributed to the device.

Jan 1, 2009

By Steven J. Schatzel, Joseph Cervik, Gerald L. Finfinger

Gas drainage through surface bore¬holes has been the conventional means of methane control for U.S. longwall gobs. However, these vertical boreholes are becoming so costly, and the surface rights so difficult to obtain, that the Bureau of Mines is developing underground gob gas drainage as an alternate means of methane control for U.S. longwal..ls. Holes are drilled into the roof over the panel and on retreating longwalls, towards the working face from a location inby the face. As the longwall retreats, an increasing portion of the hole inter¬cepts the fracture system over the caved gob. A surface exhauster maintains a vacuum on a pipeline parelleling the panel and draws the methane mixture out of the mine. Auxiliary systems of gob gas drain¬age during longwall mining will be essen¬tial for an increasing number of coal mines. Deep and gassy mines often find ventilation insufficient for adequate dilution of methane in bleeder entries. Although this cross-measure method of degasification has been used successfully in Europe, some of the European tech¬niques cannot be directly applied to U.S. mines. This is the first study of its kind in this country.

Jan 1, 1982

By C. H. Herty

[Ferromanganese continues to be in indispensable requirement in steel manufacture. Approximately 470,000 tons of the 80 per cent ferro-alloy was consumed in 1929 and increasing amounts will be required annually by the steel industry unless some satisfactory substitute is found. An average of 14 pounds of metallic manganese is for each ton or steel produced, The principal use of manganese is for deoxidation of the metal in the steel refining processes, although a considerable amount r s also used for the production of special manganese steels. Unfortunately, domestic production of manganese ore is inadequate to meet normal peace-time requirements, not to mention increased abnormal war-time demands.]

Jan 1, 1930

By Frank E. Federspiel

In 1992, the Bureau of Mines conducted a mineral resource investigation of the 19,200-hectare Garfield Mountain study area in east central Idaho. The area had been proposed for Wilderness. Cretaceous-age quartzite and limestone conglomerates underlie the area's east half; thick travertine beds, as well as limestones, dolomites, sandstones, and volcanic tuffs occupy the west half. All the rocks have been faulted and folded as part of the Western Overthrust Belt. Two, enormous travertine deposits occur in the west end of the study area. The lower deposit, controlled by Faxe Kalk Inc., has at least 200 million m3 (cubic meters) of travertine resources. Most of their deposit is very bright with a high CaC03 content and a low insoluble residual percentage: thus it is suitable for use as a paper and paint filler. The upper deposit, owned by Idaho Travertine Corp., contains 100 million m3 of travertine resources; it is used for facing or dimension stone. Weathered travertine outcrops are buff to tan and locally vuggy. Bureau of Mines samples of' outcrops contained greater than 95% CaC03. Approximately 600 m3 of travertine have been quarried from the two deposits and used for facing stone. Four travertine quarries and two dozer cuts were examined. Faxe Kalk has 103 White Rock placer claims on the lower deposit; approximately one-half of the claims are within the study area. Idaho Travertine has the Limestone 1 and 2 placer claims on the upper deposit. A 4,647-m-deep oil and gas exploratory well was drilled on the east end of the study area without success.

Jan 1, 1993

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