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By Donald F. Reed

During the first 6 months of 1948 the Bureau of Mines investigated the titania, deposit on the Wynn 0. Christy property in northern Hot Spring County, Ark. The property is situated in Magnet Cove, about half a mile north of the Magnet Store and U. S. Highway 270 (fig. 1). The purpose of the investigation was to determine the extent and grade of the ore body and to obtain a representative sample of the ore in as nearly natural condition as possible for use in metallurgical testing. All of the titania that has been marketed from Arkansas mines has been in the form of rutile from a deposit about 2 miles west of the Christy property. The titania in the Christy property occurs principally as brookite, which, with fragments of novaculite, quartz, and limonite, is imbedded in red clay. It is difficult to recover a core of the material. Three types of drills - a diamond drill, a bucket drill, and a Baker cable-coring tool operated on a churn rig - were employed in an effort to procure proper samples in their natural state. The Baker tool was found to be the most efficient and to be capable of drilling to a depth of 150 feet, making 80 to 100 percent core recovery (fig. 8). Total footage drilled was 1,536.9 in 21 holes, of which 7 were diamond-drill holes, 13 were bucket drill holes, and one was drilled with the Baker tool. The ore body was found to be 900 feet long, 500 feet wide, and more than 141 feet deep and contained 5.8 percent TiO2 and 0.52 percent 1720. Most of the deeper drill holes bottomed in ore, and there is a possibility that the ore may persist to a depth of several hundred feet. The Metallurgical Division of the Bureau of Mines is conducting experimental work at the Mississippi Valley Experiment Station at Rolla, Mo., for the purpose of developing methods of concntrating and utilizing the ore.

Jan 1, 1949

By Theresa Y. Schulz

It is interesting to study the noise standards that have been promulgated in the US over the last decade or so. These regulations are likely to have long-lasting impact. The Occupational Safety and Health Administration (OSHA) Hearing Conservation Amendment (March 1983) continues to have influence not only in the workplace but in the debate over new regulations. Both the Mine Safety and Health Administration (MSHA) and Federal Railroad Administration (FRA) regulatory preamble documents state the desire to be consistent with OSHA. An examination of Table 1, which compares the major components of the three regulations and the 1998 NIOSH “best practices” criteria, depicts the extent to which that intent is met. There has been some regulatory activity in the last decade which may give some hope for evolution and updating based on the wealth of science that has occurred during the last quarter of a century since the OSHA regulation was enacted. However there has also been some “back-sliding” toward more lenient standards. The MSHA noise standard made regulatory progress in September 2000 by emphasizing engineering and administrative controls, followed by personal protective equipment, in the hierarchy of noise intervention. MSHA’s requirement for technician certification (today only available from CAOHC) strengthened the training requirements for audiometric testing in hearing conservation programs and MSHA also added the requirement of dual hearing protection at 105 dB TWA. There were many subtle differences between OSHA and MSHA based on comments and a desire to clarify some of the vague aspects of the OSHA noise standard, and meet the needs of the regulated mining industry. One example pertains to the ceiling for exposures. OSHA says, “no exposures >115 dBA,” which is interpreted to mean no unprotected exposures above that level, giving credit for the assumed effectiveness of hearing conservation programs, hearing protection devices and administrative and engineering controls. MSHA specified that a “P” code1 violation be issued for any protected or unprotected exposures >115 dBA. The Federal Railroad Administration (FRA) noise standard for railroad operating employees, which went The Modern Evolution of Hearing Conservation Regulationsinto effect February 26, 2007, was expressly based on the OSHA standard but also uses MSHA for comparison. The preamble states that the FRA defers to OSHA as the “primary regulator of noise in the workplace,” but also acknowledges the need for some departure from the OSHA regulation (FRA Preamble II.B). As an example, FRA requires testing at 8000 Hz “because it will allow employers to identify hearing loss sooner.” The FRA rejected MSHA’s hierarchy of noise controls in favor of requiring specific engineering interventions and focusing on appropriate hearing protection which would still allow communication and audibility, and identification of excessive noise through employee-filed “excessive noise reports.”2 Where OSHA has no specific mandate requiring employees to take advantage of the employer-paid audiogram, it has been traditionally a condition of employment and is generally accepted that OSHA-covered workers require an annual audiogram. MSHA addressed this issue in its preamble; however, they made no significant change. MSHA employers are required to offer annual audiograms but MSHA stopped short of requiring employees to comply with annual audiometric testing. The MSHA preamble does allow that mine operators can also make audiometric monitoring a condition of employment. FRA requires employees to

By D. E. Hirsch, J. W. Davis, Norman G. Foster, F. G. Schwartz

This investigation was undertaken to identify nitrogen , oxygen , and sulfur compounds (polar components ) found in catalytically cracked distillate fuel . It is significant that these compounds concentrate in the sediments and gum that form when the fuel is stored . The polar components were divided in three portions by elution from a chromatographic column filled with alumina . After the hydrocarbons were washed through the column with pentane , a benzene eluted extract was removed followed by an ether eluted extract and then an alcohol desorbed fraction . These extracts were individually distilled in a molecular still and the fractions were analyzed by gas chromatography , mass spectrometry , infrared spectrometry , and elemental and functional analyses . Naphthalene and its homologs , phenanthrene and its homologs , and other compounds such as methyl indene , C₂ quinolines , phenyl indan , and the benzothiophenes , appear in the benzene extracts . Quinolines are the major components of the lower boiling fraction of the ether extract , although carbazoles , acridans , and indoles are present in some concentration . Elemental and functional group analyses of the alcohol fraction indicated 10 percent of the distillate portion was nonhydrocarbon , and in this portion the average molecule contained more than one nonhydrocarbon element . Compounds of such complexity are not well known , and standards for positive identification are limited .

Jan 1, 1963

By Robert W. Gordon

This report describes the results and conclusions of the further development of a lightweight probe drill for use in anthracite mines. Improvements to the drill previously developed under Contract H0282044 were made and tested at an Eastern Pennsylvania mine. These improvements were: 1. Better hole cleaning due to the development of an air-water mist flushing system. 2. The application of roof drill bits to allow drilling through rock seams and lenses. 3. The development of a quick coupling drill system which reduced total steel change time. 4. Adaptation of a swivel to the drill anchoring system which greatly reduced set-up time between holes. With these improvements the probe drill demonstrated its ability to drill the required 11 holes in one shift. It also gained miner acceptance as a viable underground working tool. The probe drill proved to meet all of the design requirements of portability, low weight drilling controllability, structural integrity and reliability. In addition to its ability to drill the required probe pattern, the probe drill has the capability of drilling long holes. By drilling several holes over 80 feet deep the probe drill has demonstrated a potential for use in robbing pillars and for methane drainage.

Jan 1, 1981

By J. Robert Wells

The Bureau of Mines has developed a spectrochemical procedure for determining 19 impurity elements in high-purity titanium metal, titanium oxides, and titanium halides in which all samples are converted to titanium dioxide. Determination of these impurities was studied in the general concentration range of 0 to 1,000 p.p.m., but different determination limits were found for the various elements. The procedure is quantitative for 18 elements but semi-quantitative3 for beryllium and has an overall relative standard deviation of 15.8 percent. Two mixtures were used, one composed of graphite and lithium carbonate plus gallium oxide and the other of graphite and lithium carbonate plus germanium dioxide. Each mixture was blended mechanically with an equal weight of titanium dioxide. Lithium carbonate served as buffer-diluent. Gallium was the internal standard for 1 impurity element, germanium for 7, and titanium for the remaining 11.

Jan 1, 1962

By Thomas Jenning, C. M. Keithly

"INTRODUCTION This report is one of a series. 4. 5. 6/ concerned with presenting historical development, and operating data on secondary-recovery projects in various States to stimulate interest in sound secondary-recovery programs. Preceding reports in this series have dealt exclusively with descriptions of and results obtained by water flooding in three states, but no recent publication of comparable purpose describes gas-injection 7/ practices. The authors intend to present material relevant to the development and operation of gas-injection projects in Illinois, with particular emphasis on those producing from oil-bearing horizons that had been depleted to a point near the economic limit of operation by past oil-recovery methods.Most operators realize that the energy expended on the movement of fluids through gas-expansion- or gas-cap-type oil reservoirs to producing wells must be supplemented to attain maximum recovery of the oil present. Under favorable conditions, many operators choose to maintain oil-propulsive forces at or near their original magnitude by injecting extraneous fluids into a reservoir or recycling produced fluids early in the life of a field. More common, and less desirable, is the practice of replenishing these forces after primary producing methods become unprofitable. The lattes practice has been adopted in many stripper fields in Illinois and most of the oil-producing States during the last 40 years, but other old oil fields, and oil properties within those fields which were partly exploited by secondary--recovery methods, also may offer favorable opportunity for further development. To encourage and, aid operators in the development of gas-injection projects in the old oil fields of the United States, four projects have been described in detail in this report."

Nov 1, 1944

By M. Dattilo

The U.S. Bureau of Mines has been conducting research on the use of waste-derived zinc as a partial replacement for pure zinc in the electrogalvanizing process. The end product of this process is automotive sheet, which has enhanced cosmetic protection over previously used cold-rolled (CR) steel. In this study, primer-coated specimens of CR and electrogalvanized (EG) steel were subjected to the on-vehicle environment and monitored periodically by electrochemical impedance spectroscopy (EIS) during immersion in 1M NaCI solution. The results of these tests were compared with immersion-only conditions. Scanning electron microscope (SEM) and energy-dispersive X-ray (EDX) techniques were also used to evaluate the corrosion processes and compare them with atmospheric exposure specimens. EIS was found to measure the corrosion associated with on-vehicle exposure, thus providing an excellent screening technique for evaluation of the performance of EG automotive sheet steel.

Jan 1, 1990

By R. P. Maloney

The Bureau of Mines conducted a reconnaissance of the less accessible parts of the Beluga River coalfield in August 1957 to determine, if possible, which areas were most favorable for developing large reserves of coal suitable for open-pit mining. Several outcrops of subbituminous coal were observed within an area about 30 miles long and 3 miles wide; neither the length nor the width of the coal-bearing area was delineated by the examination. Coal beds 30 feet thick or more outcrop at two places, and beds 5 to 20 feet thick or more outcrop fairly abundantly along the Beluga River and its tributaries The coal measures appear to occur in a series of folds. The overburden comprises glacial gravels and poorly cemented sandstones and ranges from 20 to 400 feet in depth. Few partings were seen in any of the coal beds. Samples ranged in calorific value from 6,240 to 8,246 B. t. u. on an as-received basis. Adequate water is available for stripping by hydraulic methods.

Jan 1, 1958

By G. J. Slavens

The Bureau of Mines has devised technology to recover cobalt, nickel, and byproduct copper from domestic lateritic material using an oxidative, ammoniacal ammonium sulfate leach. Nickel, cobalt, and copper were recovered by solvent extraction and electrowinning. To reduce the cost and complexity of cobalt recovery, an alternate method using lig-nite to extract Co3+ was investigated as reported herein. In the first 25 BV (bed volumes) of solution contacted with lignite, 97 wt pct of the Co3+ was extracted in & downflow column at pH 9.3. After 85 BV, the lignite was loaded to 1.5 wt pct Co3+ and further ex-traction was minimal. The lignite extracted cobaltic ammine complexes rather than cobalt ions and was nonselective as to other -metal cations and ammonium ions. Deleterious cations and 80 wt pct of the nonammine ammonium ions were removed prior to acid elution of the lignite. The removal of the ammines prior to elution to produce an ammonium-ion-freeCo3+ eluate was only partially successful. Thus Co3+ removal from ammoniacal solutions by lignite is technically difficult and economically unfeasible. It was also determined that reduction of Co3+ to Co2+ occurred during the extraction-elution process.

Jan 1, 1984

By W. M. Merritts

The control of coal dust created and released during the operation of continuous mining machines in bituminous-coal mines of the United States is a problem. The interest manifested in this problem indicates the seriousness of the hazards involved, particularly when the dust has not been abated at its source and has become air-borne. Officials of the Sunnyside No. 1 mine, Kaiser Steel Corp., were confronted with the problem of abating the coal dust created by operation of a recently installed continuous-mining machine, and they requested the aid of representatives of the Coal-Mine Inspection Branch, Bureau of Mines, United States Department of the Interior, in developing an effective method of allaying the coal dust at its source.

Jan 1, 1951

By Eric G. Kok

Complying with respirable dust standards is presently a critical problem for many longwall faces equipped with double drum shearers. Results are presented of research performed to increase the quantity and optimize the distribution of the water supplied to the shearer drums to control the shearer operator dust exposure. The effect on the total respirable dust produced by the shearer was also examined. During the research effort, a simple and inexpensive manually controlled valve system was designed and implemented on a shearer to distribute the water supplied to the shearer drums. Research showed that increases in water quantities are beneficial but associated pressure increases may induce respirable dust boilover negating potential advantages. Other essential parameters such as location of shearer operator, outside spray orientation and air quantity were considered in the evaluation.

Jan 1, 1986

By W. G. Hopkins

The development of systems for location of miners who have become entrapped following a mine disaster has been one of the major research goals in the Bureau of Mines. This study details the preliminary development of such a system. Current technologies for locating trapped miners from the surface are either simple direction finders or time difference pulse systems that have accuracy limitations. Developing technologies using full vector field measurements at several receiving points are currently being studied. The necessity of measuring field strength with great accuracy can be a drawback in these systems. A system that operates with continuous wave radio signals, whose phase differences can be measured accurately even in weak signal conditions, greatly improves the location accuracy. A microcomputer would be used in conjunction with the system, to gather and manipulate the data to automatically pinpoint the location of the trapped miner. Comparison of this system with existing technology indicates a favorable accuracy/complexity ratio for the phase difference of arrival technique.

Jan 1, 2011

By Edwin M. Murphy

Methods are described for filling underground cavities remotely with dry material pneumatically injected through a borehole to seal openings, prevent air movement, and reduce subsidence; this often brings underground fires under control by limiting the access of air. Large-scale tests were made in the Bureau of Mines Experimental Coal Mine, Bruceton, Pa., in an operating mine, and in an abandoned Pennsylvania mine. Supplemental trials were made aboveground in galleries and in the laboratory. The parameters studied include horizontal and inclined passageways, obstructions in the entry, water leakage into the borehole, dry material, and grout and slurry mixes. The materials studied were fly ash, crushed and pulverized limestone, and sand. Best results were obtained with dry fly ash, though satisfactory seals were obtained with the other materials. When a borehole is dry and ends at an open void, casing is not necessary. If more than 5 gpm of water flows in the borehole, if the void contains loose debris, or if coarse material is injected, a material feedpipe should be inserted through the borehole. Fly ash was most suitable for remote filling because of its low angle of repose (8°) and its good flow characteristics. The depth of borehole through which the fly ash is injected has no appreciable effect on the filling operation.

Jan 1, 1968

By R. V. Ramani, J. Qin

"During the mining process, the insitu material is broken into different size ranges, from very, large pieces to very fine particles. Some of the fine particles become airborne. In underground coal mining, airborne respirable. dust is associated with health and safety of the miners: The amount and size distributions of airborne dust are important parameters to effective dust control measures. The design of underground mine experiments, including sampling procedures and sample analyses methods to determine these parameters are presented in this paper.. A total of fifteen continuous miner cuts were sampled. The amount of dust generated during the cutting process and the relationship between total and respirable airborne dust concentrations and amounts are examined.The amount of respirable dust airborne is on the average only. 0.016% of the respirable dust generated. On the average, 61% of the total .airborne dust measured is in the respirable size range. The amount of respirable airborne' is on the average 36% of the respirable size fraction in the total airborne dust. For equal proportion of rock and coal material cut, rock contributes about twice as much fines (<0.22 mm) as coal. Additional fundamental research is necessary to further the understanding of 'the airborne propensity of respirable dusts in mine atmospheres.INTRODUCTIONMining is a sequential process of breaking, gathering, loading, and transporting the in-situ .materials.' In underground coal mines, duet in both the non-respirable and respirable size ranges is generated and entrained in every phase of the process. Even though large amounts of dust particles' adhere to run-of-mine coals, part of the dust generated becomes airborne (Cheng and Zukovich, 1973). Studies have shown that bit type affects the amount of dust generated'(Evans and Pomeroy, 1966; Kurth et al., 1975; Roepke et al., 1976; Stecklein et al., 1982; and Khair and 'Reddy, 1986). Deep cutting can reduce airborne dust generation (Black and Schmidt, 1977 arid, Black et 1978). Mechanical properties of. coal seams are also important factors in dust generation. Laboratory studies have shown that Hardgrove Grindability Index (HGI) of the coal has a relationship with the amount of respirable. dust generated (Beafi and Ramani, 1979; Moore and Bise, 1984; and Moore, 1986). However, these relationships have not yet been validated with' data from the mines. The amount of dust airborne depends on a number of factors. Suppression of the airborne propensity of dust by water sprays is'widely practiced and is very effective. Water flow rate; pressure and configuration of water sprays have been identified as major factors affecting dust capture by sprays (Courtney and Cheng, 1977; Courtney et al., 1978; and Kissell et al., 1979). Ventilation is a very important means of controlling the dust level at the coal face (Jayaraman, 1977). According to a National Academy of Sciences study (1980), the mechanism of dust generation and the process by which the generated dust becomes airborne are complex and not yet completely understood coal seams are also important factors in dust generation. Laboratory studies have shown that Hardgrove Grindability Index (HGI) of the coal has a relationship with the amount of respirable dust generated (Beafi and Ramani, 1979; Moore and Bise, 1984; and Moore, 1986). However, these relationships have not yet been validated with data from the mines. The amount of dust airborne depends on a number of factors. Suppression of the airborne propensity of dust by water sprays is widely practiced and is very effective. Water flow rate; pressure and configuration of water sprays have been identified as major factors affecting dust capture by sprays (Courtney and Cheng, 1977; Courtney et al., 1978; and Kissell et al., 1979). Ventilation is a very important means of controlling the dust level at the coal face (Jayaraman, 1977). According to a National Academy of Sciences study (1980), the mechanism"

Jan 1, 1989

By N. E. Hanna

Experience with the current version of gallery test 4, in use since 1913 to evaluate the incendivity of permissible explosives in the presence of coal dust, has shown the procedure to have inadequate discrimination. Consequently the Bureau of Mines used the up-and-down method of statistical design to investigate the incendivity of permissible explosives in the presence of coal dust and gas. A suitable device was developed to measure coal dust concentrations in the air-gas mixtures and to disperse the dust in the gallery atmosphere. A proposed testing method which uses suspended shots in a predispersed coal dust-gas-air mixture was evaluated. The new method can discriminate between different explosives with respect to their incendivity. Maximum ignitibility of the coal dust cloud by permissible explosives occurred in the vicinity of 0.3 oz/cu ft. About 10% sodium chloride in permissible explosive formulations had a very significant effect in reducing the probability of igniting coal dust. Bundled charges were more incendive than column charges.

Jan 1, 1966

By G. W. Jones

In a previous report,6/ results were given that showed the amount of natural ventilation in a manhole having a capacity of 74.1 cubic feet when the number of ventilation openings in the cover was varied from no openings to a maximum of 48. The result s showed that the ventilation (air changes per day) in the manhole was proportional to the area of the openings in the cover, and also that the number or area of the openings was the factor that chiefly affected the ventilation.

Jan 1, 1937

By R. Karl Zipf

MULSIM/NL (multiple scams, nonlinear) is a three-dimensional boundary-element method (BEM) program developed at the U.S. Bureau of Mines for stress and displacement analysis of coal mines and thin metalliferous veins. It can analyze one to four parallel seams that can have any orientation with respect to the Earth&apos;s surface. Three main new features distinguish MULSIM/NL from its predecessors: (1) nonlinear material models, (2) multiple mining steps, and (3) energy release and strain energy computations. MULSIM/NL has six material models for the in-seam material: (1) linear elastic for coal, (2) strain softening, (3) elastic plastic, (4) bilinear hardening, (5) strain hardening, and (6) linear elastic for gob. Detailed checks show that numerical stress and displacement calculations compare well to known analytic solutions for simple problems. The total energy release calculated by MULSIM/NL is comprised of three basic terms: (1) strain energy release from the mined-out material, (2) linear kinetic energy release due to change in gravitational potential over the mined-out area, and (3) nonlinear kinetic energy release due to nonlinear materials in the total backfill and gob area. The strain energy release term is modified to account for nonlinear stress-strain behavior in the unmined materials. Comparisons of these numerical energy release rate calculations with known analytic solutions show excellent agreement.

Jan 1, 1992

By S. J. Broderick

[Huge camp heaps coat. in-.n,- ta._ur nd o tons of coal :&apos;efuse are a familiar sight in coa).--:1&apos;_ni`l ; res io The;;&apos; repre£e: t considerable economic loss, are very ~JZ&apos;:Si~i,tly, and tr:_ e u.: mach v lua-ble :price. Consequentl;;* their remcva7. is ,-,reatl:r de sir^~t~ a_." ar return that c,-u? be obtained would. be especially rel.co c to the coal T,-e "a_ste nat(~ria1 commrioes large pieces of bore cca1., lumps rf c12;&apos;, -)nd finer refuc3 coming from the &apos;acxcor~-, Tnc e&apos;-:s: rr;I refuso contains some Food coal. Th1S coal and the better crams of _,)ore Pre t&apos;--:e na.torials considered. in ohis in¬vestigotion. T&apos;.-.r, heavier fractions of the vas ier,,refuse a rd. the large pieces of slate a n i roc _r contain little carbcnacaous r..aterinl -.nd axe ~vir¬ tually worthless ra&apos;., :,atcria1. for activated carbon. In the E i 1i 11?&apos;ar 1 dictrict~ n1ab a :1 ut irfl percent of the&apos; coal mined is wa^,hed., and in district rc_a e -c-cnuatcs at the r..-ate of I to 2 Million tons a year?]

Jan 1, 1941

By Farrel W. Lytle

Instrumental analysis has become an indispensable tool in research and production of the rare-earth elements. This development can be attributed mainly to a combination of two factors--the marked chemical similarity of the rare-earth elements, which excludes classical methods of analysis, and the speed and accuracy of instrumental-analysis techniques. With continued improvements in methods of producing high-purity rare-earth elements, keeping pace instrumentally is becoming much more difficult. Accordingly, greater emphasis is being placed on improving instrumental limits of detection and accuracy. The methods employed most frequently for determining impurities in rare-earth elements involve use of the optical-emission spectrograph (3, 4)4/ and the spectrophotometer (9). Although numerous X-ray-emission spectrographic methods (6-8) have been developed for analyzing rare earths, these techniques have not included detection of low-level impurities. This investigation was conducted to find the precision and accuracy of X-ray fluorescence in deter-mining impurities in rare-earth oxides in the 0.01-to 1.0-percent-concentration range.

Jan 1, 1959

By A. C. Fieldner, S. H. Katz

"Introduction.Recent experiments (Fieldner, A.C., Katz, S.H., Kinney, S.P., and Longfellow, E.S., Poisonous gas from carbon tetrachloride fire extinguishers, Jour. Franklin Institute, October, 1920, pp. 543-565), by the Bureau of Mines have shown that carbon tetrachloride extinguisher liquids when applied to fires produce small quantities of irritating and poisonous gases which may be dangerous in very closely confined spaces where conditions are such that the user can not escape without breathing the fumes. The results of the experiments have been confirmed in an independent investigation by the Underwriters Laboratories (Nuckalls, A.H., Corrosive action and products formed when carbon tetrachloride extinguisher liquids are applied to fires, Nat. Fire Protection Assoc. Quarterly, vol. 14, January, 1921, pp. 221-236) who conducted similar experiments for the purpose of determining the corrosive action of these fumes on metals. Both investigations showed that carbon tetrachloride vapor, hydrochloric acid gas, and phosgene were produced in addition to the ordinary products of combustion, such as smoke, carbon monoxide and carbon dioxide. The Bureau of Mines' tests were made by applying a one-quart extinguisher to a wood fire of excelsior in a gas-tight room of 1000 cubic foot capacity. The glass and metal construction of this chamber limited the experimental fire to very small dimensions. It was, therefore, deemed desirable to make a test on a larger scale in the entry of the Bureau's experimental mine in order to similate more nearly the practical use of carbon tetrachloride and other types of extinguishers in mines.Description of extinguishers.Two series of tests were made under identical conditions on different days. Commercial carbon tetrachloride extinguishers were used in the first series of tests and ""foamite firefoam"" extinguishers in the second series of tests."

Jun 1, 1921