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By R. V. Ramani, C. B. Manula, A. Owili-Eger

All the input data required to operate the ventilation simulator except the title, are entered with I10 or F1O.O formats. The title is entered with (18A4) format. The floating points are designated by (FP) and the integers by (INT)

Jan 1, 1975

By R. V. Ramani, V. T. Burgos, J. A. McClay

This report was prepared by The Pennsylvania State University under USBM Contract No. G0111808. The contract was initiated under the Coal Mine Health and Safety Program. It was administered under the technical direction of DMSE, with Mr. G. R. Schottler acting as the technical project officer. Mr. J. A. Herlckes was the contract administrator for the Bureau of Mines. This report is a summary of the work recently completed as part of this contract during the period June, 1971 to September, 1974. Thls report was submitted by the authors on February 13, 1975.

Jan 1, 1975

By Fred N. Kissell

The U.S. Bureau of Mines was established in1910 to reduce .the high accident rate in the nation's coalmines. For 85 years, it conducted a wide variety of tasks related to mining before it was abolished in 1995. The BOM had many technology transfer successes in its lifetime, including more than a dozen "R&D100" awards. This essay identifies and discusses five "transfer factors" that can explain the success (or failure) of many Bureau of Mines projects. These five factors are termed "pressure, pitfalls, path, price, and profit."

This chapter presents data on occupational exposures from several sources. Data from compliance samples obtained by MSHA inspectors are presented in table 6-1 for coal mine dust and silica dust, and in tables 6-2 through 6-6 for metal fumes. Since these samples were taken for compliance monitoring rather than as part of a survey of the industry, it is difficult to predict how well they indicate actual exposures for all mining operations. In the coal industry, 7.8% of all respirable dust samples during 1986-1995 were above the permissible exposure limit (PEL). Of silica dust samples obtained during the 10-year period, 23.7% were above the PEL in coal, 16% in metal, 10.8% in nonmetal, 9.1% in stone, and 7.6% in sand and gravel. Of metal fume samples, silver samples showed the largest percentage above the PEL-approximately 48% of samples in both metal and nonmetal. Tables 6-7 and 6-8 present data on noise exposures from the MSHA "dual threshold" survey, which was published in the Federal Register [61 Fed. Reg. 66347 (1996)] as part of a proposed rule change for occupational noise exposure in mining. This study examined a group of samples obtained during 1991-1995 and compared the percent of samples that were above two separate specified limits. The first limit was the current noise standard, a time-weighted average of 90 dBA, calculated to include only exposures at 90 dBA and above. The second limit was a time-weighted average of 85 dBA, calculated to include exposures at 80 dBA and above. Tables 6-8 and 6-9 refer to musculoskeletal overload conditions examined in the National Occupational Health Survey of Mining (NOHSM) [NIOSH 1996]. Table 6-8 shows the operational definitions for each condition; table 6-9 shows the percentage of the workforce potentially exposed, by commodity. Across all commodities, a large proportion of workers were exposed to musculoskeletal overloads due to positioning of the neck and back; positioning and motion of the forearms, arms, and shoulders; heavy lifting; and positioning and movement of the lower limbs. The recorded overloads were defined in the survey and did not exceed any NIOSH, MSHA, or OSHA guidelines for musculoskeletal overloads. Further information on this survey appears in appendix A.

Jan 5, 2000

By L. A. Johnson

This Bureau of Mines report presents the analysis of three cores from the Asphalt Wash area of the P.R. Spring tar sand deposit of northeastern Utah. Two tar sand zones are indicated in the Asphalt Wash Area. Total net thickness of the tar sand ranges from 23 to 39 ft, with occurrences between 56 and 263 ft in depth. The sand has average porosity of 24.7 pct of bulk volume, average permeability before and after extraction of 87.5 and 596 md, respectively, and average oil saturation of 58.1 pct of pore volume. Oil gravity averages 10.9° API.

Jan 1, 1975

By George J. Carter, George H. Todd, Hal J. Kelly

In July 1956, the Bureau of Mines and the J. R. Simplot Co. participated in evaluating and beneficiating drill-hole samples from the Bovill, Idaho, clay-silica deposit and in tests of the beneficiated products. The geology, mineralogy, beneficiation, and potential uses of the clay and quartz fractions of the Bovill deposit are described. Test work showed that a filler-grade clay having an apparent spectral reflectance of 78 percent can be made by bleaching, and by removing some of the submicron-size particles. A quartz product suitable for the manufacture of glass containers can also be made.

Dec 1, 1963

By Alla D. Mah

Combustion energies of barium and strontium were measured by means of the combustion bomb calorimeter. The heats of formation obtained for the oxides were ?H298.15 = -139,060 ± 700 cal/mole of barium oxide (BaO) and ?H298.15 = -144,440 ± 400 cal/mole of strontium oxide (SrO). Tables containing heats and free energies of formation from 298.15° to 2,000° K were prepared.

Jan 1, 1963

By I. D. Shah

Thermal decomposition of copper (II) sulfate (CUS04) and copper (II) oxy-sulfate (CuO?CUS04) are important steps in the overall oxidative roasting of covellite (CuS) and chalcocite (Cu2S). Nonisothermal thermogravimetric techniques were used to investigate the decomposition reactions in flowing Na and air. Thermal decomposition of CUS04 and CuO?CUS04 followed "linear" kinetics with an apparent activation energy of 55±2 and 66±3 kcal per mole decomposed, respectively. These apparent activation energies comply with those previously reported when isothermal kinetic techniques were used. The addition of oxygen decreased the rate of decomposition, while small amounts of iron which were admixed with CuO?CUS04 did not have a significant effect. Neither oxygen nor iron had any appreciable effect on the apparent activation energy of the decomposition reaction.

Jan 1, 1972

By S. R. Zimmerley, John Gross

"The investigation discussed in this paper was undertaken to obtain fundamental data on crushing and grinding and has been confined, so far, to work on quartz.The results of crushing or grinding have hitherto been judged entirely by the amount of the various-sized particles produced, based. on sieve sizing for particles above 74 microns in size and on microscopic measurement or elutriation for particles below 74 microns - a method which could give only a general idea of what had been accomplished.There was a distinct need of a ""yardstick"" for the measurement of crushed material. It appeared that no advance in the fundamental investigation of crushing and grinding could be made without a reliable method of surface measurement and that such a measurement would have to be based on some property of the surface of the crushed material.A number of attempts based on various surface actions, such as adsorption and heat of wetting, were made to measure surface on quartz particles, but all gave unsatisfactory results. After some preliminary work it was decided that a dissolution method based on Wenzel's law-- ""the reaction velocity between solids and liquids is proportional to the area. of contact""4 -- would be the most feasible.Early use of the dissolution method had been made for surface measurements5, and lately Dr. Geoffrey Martin and his coworkers in England used the dissolution method to determine surface on quartz. They compared the amount of quartz dissolved from a sample in one hour by a hydrofluoric acid solution, with the amountdissolved from a measured quartz cuboid6,After investigating the solvent power of sodium carbonate, sodium hydroxide, and hydrofluoric acid for quartz, hydrofluoric acid was selected as the most suitable solvent, and a dissolution method was developed which gives very reliable results.During the dissolution of quartz in hydrofluoric acid, the reaction velocity changes for two reasons: there is a change in concentration of solution, and a change of surface of the solid. The amount of quartz dissolved in a definite period of time is therefore not a true measure of surface. If, however, the reaction velocity or rate of dissolution for various periods of time be plotted, a curve will be obtained which, if extrapolated to the zero time ordinate, will give the rate of dissolution before any change of surface or any change in the solvent has taken place, and which is a true index of surface. This rate of dissolution, expressed in percentage of the original sample at the zero time ordinate, is designated herein as the ""Initial Rate"" or as simply ""I. R."""

Jul 1, 1928

By Daniel N. Tallman

To provide technology for achieving more efficient water filtration systems for the mineral industry, the Bureau of Mines performed demon-stration filtration tests at three iron ore mines and one steel mill. A comparison of equivalently sized magnesium oxide (MgO) and sand filters showed that MgO had a higher capacity and could operate at higher fil-tration rates than sand. In demonstration tests when alum (AlK(S04)2) was the coagulant, suspended solids breakthrough occurred even though the pressure across the filter (head loss) was 7 psig or less. Under these circumstances, the MgO demonstrated 20 to 100 pct greater filtra-tion capacity, defined in terms of the volume of water filtered before breakthrough. When an organic floccu1ant was used at one location, head loss was the run-limiting factor; the filters essentially plugged with-out any solids breakthrough.

Jan 1, 1985

By Raymond M. Kacmar

This paper describes the Bureau of Mines research program on the reliability of computerized mine-monitoring systems. The basic concepts of computerized monitoring are introduced along with its advantages and limitations. Current Bureau projects covering mine-monitoring systems are described, and some of the major areas of concern that should be addressed by future projects are outlined.

Jan 1, 1982

By F. R. McDonald

This report presents a discussion of the spectra of 39 condensed thiophenes in which the structure includes at least 1 benzene ring. The vibrational bands present in three regions of the infrared spectra of these thiophenes were interpreted by comparing the similarities of the spectra of condensed thiophenes with the spectra of substituted benzenes. In the overtone-combination region 23 of the 39 condensed thiophenes had spectra which contained sufficient detail to be usable for correlating this region of the spectrum with the appropriate benzene spectrum. In the in-plane deformation region it was possible to make correlations for the vibrations of 18 of the 39 condensed thiophenes whose infrared spectra were studied. In the out-of-plane deformation region the C-H out-of-plane vibrations for hydrogen on benzene rings in the condensed thiophenes can be correlated using known data from substituted benzenes.

Jan 1, 1967

By M. G. Cherniack, A. J. Brammer, D. R. Peterson

Over the past two decades, there have been significant reductions in industrial exposures to hand-arm vibration, especially when specific tools and work processes have been redesigned to incorporate anti-vibration and ergonomic principles. Nevertheless, Hand-Arm Vibration Syndrome (HAVS) remains a significant occupational health problem as disease symptoms continue to occur even when vibration exposure levels believed to incur low risks have been reached2. This inconsistency may be related to the methodology that is typically used to estimate workday vibration exposure levels, involving laboratory and/or very short duration field measurements coupled with estimates of overall eight-hour tool operation times determined from brief observations of tool tasks and/or self-reported surveys. One solution is to use small, commercially-available, personal vibration dosimeters to calculate, record, and display long-duration vector sums and energy equivalents of vibration. However, since these devices are attached to the worker and require tool-mounted accelerometers, they are incompatible with the worker performing normal duties involving putting down or changing tools. In addition, these commercial systems do not allow for the characterization of the transmission of vibration to the hand such as monitoring the mechanical coupling between the hand and the tool handle (e.g., grip forces). O’Boyle and Griffin showed that variations in applied force can alter vibration transmission characteristics by 50% or more indicating that the measurement of grip force is essential for modeling vibration transmissibility and vibration exposures5. In summary, a need exists for the development of a method and device that will more accurately characterize workday-long vibration exposures. Methods A portable, light-weight, Vibration Exposure Monitor (VEM) system was developed to record user-specific tool-operating times, vibrations, and grip forces throughout all, or a representative part, of a workday. It monitors frequency weighted and unweighted accelerations from a palm-mounted uni-axial accelerometer (Model 352C22, PCB Piezotronics, Depew, NY) and calculates exposure levels using the root-mean-square (RMS) and higher power mean values, such as the root-mean-quad (RMQ) and the root-mean-oct (RMO). Grip forces are also monitored using a palm-mounted force sensor (Model 400, Interlink Electronics, Camarillo, CA) from which average grip force levels and exerted grip extrema are calculated. At the core of the VEM system is a commercially available, battery-powered microcomputer (Tattletale, Model 8v2, Onset Computer, Onset, MA) with one megabyte of memory and eight analog channels using 12-bit sampling at a single-channel maximum of 100 kHz. Analog signal processing (i.e., anti-aliasing, with cutoffs at 4 and 1250 Hz, and ISO 5349-13 frequency weighting) is accomplished using custom circuitry that is directly interfaced with the microcomputer. An embedded C-based protocol governs the data collection from each channel

Jan 6, 2006

By Ann G. Kim

Hydrocarbon gases, primarily methane but also the Ca through Cs paraffins, the Ca and C3 olefins and possibly the C4 and Cs olefins, are byproducts of coal formation. Although it is generally believed that coal formation occurred at temperatures below 200° C, most experimental work on gas formation from coal has been performed at temperatures between 200° and 1,000°C. The objective of this Bureau of Mines experiment was to determine if observable changes in the gases from coal could be produced at temperatures below 200° C in relatively short periods of time. The experiment involved heating coal samples from six coalbeds at constant temperatures and analyzing evolved gases. The composition of the gases at three temperatures was compared. At 35° C, over 99 pet of the gas is methane; at 125° and 150°, methane constitutes approximately half of the hydrocarbon gas. Isobutane and pentane are the predominant higher hydrocarbons at temperatures between 100° and 150° C.

Jan 1, 1974

By A. Gene Collins

Some of the geochemical relationships that exist between subsurface fluids and the associated geologic strata in petroleum producing areas of Louisiana have been determined. Samples of petroleum-associated water were obtained from 126 wells in Louisiana that produced from sediments of three geologic ages: Tertiary, Cretaceous, and Jurassic. The samples were trans-ported to a central laboratory for analysis of chemical composition, using standard methods, to determine if the compositions varied with the geologic strata of their source and, if so, why. The dissolved constituents were com-pared with those of a brine that was concentrated by evaporation. The concentrations of bromide, calcium, and strontium were useful in distinguishing the brines produced from sediments of a late age from those of an earlier age. The concentration ratios of Mg' (total equivalent magnesium) and bromide indicated that dolomitization probably had occurred and altered the composition of the brines. A principal-components analysis of the data indicated an inverse relationship between depth and concentrations of bromide, strontium, calcium, and lithium.

Jan 1, 1970

By Van E. Shaw

Bastnaesite is a natural rare-earth fluorcarbonate of the cerium group that affords an abundant and high-grade source of the lighter rare-earth elements. A simple and efficient method has been developed by the Bureau of Mines for extracting rare-earth compounds from this mineral. Digesting of a flotation concentrate with sulfuric acid converts the rare-earth compounds from fluorcarbonates to sulfates. Action of the acid releases gaseous com-pounds of fluorine and silicon, leaving the sulfated material free of these elements; carbon dioxide from carbonate decomposition is eliminated at the same time. Calcining the sulfated material at 1,200° F. renders the gangue constituents insoluble, whereas the rare-earth sulfates are left in water-soluble form. Leaching with water yields a solution of pure rare-earth sulfates. Bastnaesite could become prominent as a source of cerium-group rare-earth elements. It is rich in the light rare-earth elements and comparatively easy to process; reserves of the mineral are extensive enough to supply a greatly expanded market for many years.

Jan 1, 1959

By Steven J. Page, John A. Organiscak

Prolonged exposure to airborne respirable coal mine dust is responsible for coal workers' pneumoconi¬osis (CWP): Furthermore, miners who show evidence of higher radiographic categories of simple CWP are at increased risk of developing progressive massive fibro¬sis (PMF). As of 1990, there were nearly 130,000 coal miners in the United States. "' This excludes mines that produce less than 10,000 tons annually and the anthracite coal mines. Estimates indicate that at age 58, an average of 7/1000 U.S. workers and 89/1000 U.K workers will have developed PMF(2-1) Health research studies have iden¬tified that the risk of developing and the severity of CWP arc directly related to (1) the amount of respirable dust exposure and (2) the coal rank.,'- The rank of coal is its stage of formation in the series peat, lignite, sub-bituminous, bituminous, and anthra¬cite (in order of increasing rank). The rank of coal can also be represented by the com¬mercially important characteristics specified by its proximate analysis: fixed carbon, vol¬atile matter, mineral matter, and moisture content.

By Albert A. Munsch

The Munsch National First-Aid Instructors Association had its inception during the teaching of a Federal Bureau of Mines first-aid instructors' class at McPherson, Kans., under a cooperative plan of first-aid training. Upon completion of- the course on July 1, 1938 members of the class organized the charter chapter of the association under the name of McPherson (Kans.) District Charter Chapter No. 1. On July 1, 1941, 3 years after the founding of the association, there were 15 chapters in the national council -7 in Kansas, 3 in Oklahoma, 2 in Texas, 2 in New Mexico, and 1 in Arkansas. Although the pioneer work of the association was done in the petroleum industry, the plan will be of even greater benefit to a district in which there are various types of plants, mince, and operations of the mineral and allied industries. ACKNOWLEDGMENTS The writer appreciates the cooperation and assistance of the following persons: S. P. Redfearn, safety engineer, Globe Oil & Refining Co. and affiliated companies, Wichita, Kans., and H. (Chief) Moore supervisor of safety meetings, Shell Oil Co., Inc., McPherson, Kans., for their untiring efforts and enthusiasm in organizing an- attending the first class, organizing three other classes, and helping to plan the work of the association

Jan 1, 1942

By Robert J. Timko, Edward D. Thimons

Sulfur hexafluoride (SF6) is an odorless, colorless, nontoxic gas that has found acceptance as a tracer gas in research on ventilation pat- terns, measurement of air leak rates, respirable dust reductions due to bagging hood modifications, and the study of airflows relating to gob boreholes. Following a short review of the SF6 sampling technique, this report describes recent Bureau of Mines projects in which SF6 was used successfully as a tracer gas, enabling researchers to acquire representative data quickly and inexpensively.

Jan 1, 1982

By W. S. Sanner

A High Splint coal was carbonized in a low-temperature, fluidized-bed sys-tem to study the effects of thermal cracking on the products of decomposition. The coal was fluidized in recycle gas at 485° to 600° C, and the products were cracked at 600°, 700°, and 800° C in a bed of fluidized coke. Yields of tar, pitch, paraffins, and olefins decreased as carbonization temperature increased. Thermal cracking of the tar vapors produced the highest tar yields at 600° C, and light oil yield increased at cracking temperatures up to 700° C. At an 800° C cracking temperature, the yield of light oil decreased.

Jan 1, 1969