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By D. B. Taliaferro

An accurate knowledge of the water content of oil-bearing sands4/ now is recognized as an important factor in calculations of the flow of oil through the sands to producing wells and in the estimation of oil reserves. To this end the Bureau of Mines laboratories are using a method that is an adaptation of the A. S. T. M. method of determining the water content of petroleum products (1).5/ However, the apparatus and technique have been altered slightly, as described in this report, to increase the precision of the method without affecting the simplicity of procedure or speed with which determinations may be made. Until recently petroleum engineers, when estimating reserves assumed that the entire pore volume of the oil-saturated parts of producing sands was filled with oil, as it was generally thought that the oil, water, and gas in any formation had separated completely during geologic time into distinct layers because of their difference in density. In 1929 Lindthrop and Nickolaeff (12) reported experimental results from which they concluded that 22 to 30 percent of the pore volume of producing sands in the Grozay district, Russia, was filled with water when the fields were discovered. Since that time numerous investigators (5, 7, 8, 10) have found evidence of water in the sands of now oil-producing fields and old fields that never produced water with the oil.

Jan 1, 1940

By Robert S. Sanford

This paper deals with truck haulage methods and costs at one of the many open-cut mines that are replacing rail haulage with heavy-duty trucks. At this mine, ore is trucked to a crushing plant, centrally located within one of the open-cuts. The requirements for efficient low-cost truck haulage are: Good trucks designed for heavy loads, adequate truck maintenance, smooth roads, and well-trained truck drivers The weighted average cost of hauling a long ton of ore to the crusher and the waste to the dump was reduced from $0.1993 in 1948 to $0.1114 during the last half of 1949, his corresponds to a cost per ton mile of $0.0864.

Jan 1, 1952

By Robert J. Hundhausen

This paper describes the methods and costs of sinking a 2-compartment shaft at the Hope mine, Clark Fork, Idaho. The Hope mine is owned by the Hope Silver-Lead Mines, Inc. Albert E. Nash, of Clark Fork, is president and manager.

Jan 1, 1948

By P. J. Dallimore

The Bureau of Mines has calculated general time-dependent solutions for radon diffusion from cylindrical and slab rock samples containing uniform radium distribution. Results have been obtained for several sets of boundary conditions. The method is suitable for determining the effective diffusion coefficient and the effective porosity for radon.

Jan 1, 1983

By K. J. Liles

To encourage the development and conservation of the Nation's ceramic raw materials, the Bureau of Mines, U.S. Department of the Interior, under an agreement with the Georgia Department of Natural Resources, evaluated samples from a clay resource located in Clay County, Ga., for use as a raw material for lightweight aggregate. The physical properties of clay samples, taken from 5-foot increments of drill cores from 11 holes, were determined. Raw materials were plasticized and extruded to produce 1/2-inch by 1-inch pieces and fired in a rotary kiln to produce lightweight aggregate samples. The resulting expanded material had excellent loose pour weights ranging from 30 to 37 lb/cu ft. The expanded test materials were crushed, sized, and used as aggregate to form concrete cylinders. The unit weight and compressive strength of the cylinders averaged 106 lb/cu ft and 3,350 lb/sq in, respectively; these values meet American Society for Testing and Materials specifications for structural concrete. The clay from the drill cores was also used to make test bars that were evaluated for building brick.

Jan 1, 1980

By Steven J. Page

The increasing concern for dust control in metal and nonmetal mining prompted the Bureau of Mines to investigate the comparative effectiveness of three wet dust control techniques for face drilling. Previous attempts to achieve effective dust control on face drills with dry collectors have not met with success, the largest problem being sustained effective dust capture at the face. Results show that (1) foam-through-the-drill can provide 95-pct average total dust reduction in gypsum; (2) water mist-through-the-drill can provide approximately 91-pct average total dust reduction and 93-pet average respirable dust reduction in salt; (3) external boom-mounted water sprays can provide approximately 50-pet average dust reduction for both total and respirable dust in salt. The investigation showed that (1) foam and water in small quantities are very effective dust control techniques for face drills when applied through the drill steel at the point of dust generation, and (2) boom-mounted water sprays are only minimally effective for dust control on face drills.

Jan 1, 1981

By M. L. Davis

The principal causes of many methane-gas explosions that have occurred in anthracite mines, especially in thick pitching veins, during recent years can be traced to lack of a satisfactory method of testing for such gas in areas adjacent to those in which blasting is to be done or other sources of ignition introduced. As coal-mine officials and inspectors are required to make examinations for methane in all accessible open workings, including high places, and permissible flame safety lamps have been used almost universally for making these examinations, considerable difficulty has been experienced in proper testing of atmospheres at elevations beyond the normal reach of the examiner, and resultant explosions have often indicated perfunctory tests. The accepted practice of testing for gas in voids or high places generally consists of raising a flame safety lamp, suspended from the end of a long drill, stick, or pipe, into the atmosphere to be tested. Disadvantages noted are: Action of the flame within the lamp cannot be seen readily when the lamp is more then 18 inches overhead, the flame will not be extinguished when less than about 4-1/2 percent of methane is present, and indications of small percentages of methane within the lamp may disappear entirely while the lamp is being lowered slowly to view; the examiner must usually be exposed unnecessarily to falling material; and the lamp may fall and be broken. Thus, the need for a more reliable, safe method of testing for gas in out-of-reach places is apparent. Several electrical methane detectors, tested and approved by the Bureau of Mines, have been used satisfactorily, though infrequently, for making the aforementioned gas tests. Some of these detectors employ a rubber aspirator bulb and rubber tubing of suitable length to draw the atmosphere from high places through and over energized parts of the detector. However, the original expense, susceptibility to damage, and awkwardness of tarrying these instruments in steep-pitch workings has precluded their general use in everyday examinations. Although not as efficient as the electrical detector for determining small percentages of methane or as reliable because of the limitations imposed by oxygen-deficient atmospheres, the modern per¬missible flame safety lamp can, it is believed, be used safely with the rubber aspirator bulb and tubing to greater advantage and with comparative reliability in testing for gas in out-of-reach places. Slight reference to this method of introducing air into a safety lamp is made in a Bureau of Mines publication of l921,2/ and it is quite possible that the method has been utilized in some manner by individuals in American mines during the intervening years. A similar method was used in connection with a nonpermissible Wolf flame safety lamp in at least one coal mine in Japan before World War II. A major change in the construction of this lamp would bar its approval by the Bureau of Mines. An American adaptation of the Wolf lamp, developed

Jan 1, 1954

By T. E. Green

The Bureau of Mines Heavy Metals Program emphasizes the need for improved analytical methods for gold determination. A commercially available ion exchange resin with high selectivity for gold was investigated as a potential method to collect gold from solution. The resin was found to quantitatively collect gold from acid solutions over a wide range of acid concentrations. Common metals were not collected by the resin nor did they seriously interfere with the collection of gold. X-ray spectrographic and neutron activation methods based on the use of papers containing this resin are proposed.

Jan 1, 1970

By Maria I. De Rosa

The major fire and fire injury findings for all coal mining categories for 1990-1999 are reported in tables 37-38. Table 39 and figure 13 show the number of fires. fire injuries, risk rates, employees' working hours, and coal production (under- ground and surface coal mines only) by time period for all coal mining categories. Table 40 shows major findings (for under- ground coal mines only) for 1978-1992. For all coal mining categories, 458 fires occurred during 1990- 1999; 157 of those fires caused 164 injuries and 2 fatalities (Ewhr = 2,070 x l0%r, Irr = 0.016: C'P (for underground and surface coal mimes only) - 10,363 x l0\t, Frr = 0.044, LWD = 14,753). Twenty-nine fires and 17 injuries involved contractors. Sixty-six fires required firefighting interventions by mine rescue teams (25 times in underground mines) and fire brigades and fire departments (at least 41 times at surface coal operations). In all, 51 fires destroyed or heavily damaged equipment (including 16 pieces of mobile equipment) because of failure of other firefighting methods, late fire detection, undetected fires, or fire size. A total of 114 fires were detected late, and 42 fires were undetected. The greatest number of fires and fire injuries occurred at surface coal mines; the highest risk rate values were also calculated for this category. For all coal operations, the ignition sources that caused the greatest number of fires were flame cutting/welding spark/slag/flames (1 03 fires or 23% with 69 injuries), hydraulic fluid/fuel sprayed onto equipment hot surfaces (98 fires or 2 1 % with 29 injuries), spontaneous combustion/hot coal (62 fires or 14%), electrical short/arcing (49 fires or 11% with 18 injuries), and conveyor belt friction (3 1 fires or 7% with 6 injuries).

Jan 1, 2004

Provide a strategy for calculating optimum distribution of selected sensors for detecting underground mine fires. Approach The Bureau of Mines performed research to determine adequate distribution of product-of-combustion (POC) fire sensors within mine entries. This placement strategy would improve the miner's chances for escape by locating sensors where they would most effectively, quickly, and efficiently detect fires resulting from coal or wood combustion. Spacing of Sensors Placement strategy guidelines were based on the performance of 160 F heat sensors with ideal operating characteristics which were placed at intervals of ten feet in underground mine entries. Data obtained from full-scale mine fires were used to estimate fire sizes and alarm activation times for the heat sensors. Various equations were then developed to determine spacing requirements for any fire detection system installed in entries of varying heights, widths, and ventilation rates.

Jan 1, 1983

By Richard J. Mainiero

The Bureau of Mines has developed a prototype nonincendive explosive rock-breaker charge that can be fired unconfined in underground bituminous coal mines without the danger of igniting a flammable atmosphere that might be present. At present, unconfined shooting in underground coal mines is prohibited, but there are situations where the use of such shots would yield an overall improvement in safety. The charge consists of 1-1/2 lb of permissible water gel explosive in the form of a short cylinder 7 inches in diameter and 7/8 inches high, surrounded by a 1 1/2-inch-thick layer of damp salt, and encased in latex rubber reinforced with cheese cloth. The latex rubber housing provides a charge package that is strong enough to resist rough handling yet is pliable enough to conform to an irregular stone surface. A charge of this shape was found to be more effective at breaking rock than charges with lined or unlined cavities. Incendivity tests in a gallery have shown that the prototype charge will not ignite a flammable methane-air atmosphere when fired. Rock- breaking tests made with limestone boulders indicate that the charge will satisfactorily break stone slabs weighing 1 to 2 tons, and that two or more charges might be effective for slabs weighing up to 10 tons. In cooperation with the Mine Safety and Health Administration (MSHA), a test protocol for the certification of these charges as "permissible" for use in flammable atmospheres is being developed.

Jan 1, 1982

By W. Wan, R. V. Ramani, J. M. Mutmansky

"Diesel particulate matter (DPM) emitted from diesel engines is currently considered to be a health problem in underground mines. As a result, attempts have been made to control DPM both by reducing emission rates and by managing the DPM that gets into the mine atmosphere. This paper presents a method for modeling the generation, transfer, and distribution of DPM in coal mining sections through the use of a convection-based computer model so that controls for emitted DPM can be evaluated. A variety of ventilation strategies and diesel deployment schemes for room-and-pillar development sections were simulated to compare their effects on average DPM concentrations at several fixed and mobile personnel locations in the section. Input data for the model was gathered from actual diesel development sections and derived from experimental study results provided by other researchers. Analyzed using the model were ventilation schemes using vent tubing and brattice, exhaust location strategies on the vehicles, and the direction of ventilation at the feeder-breaker location. A summary of results from this study is presented.With diesel equipment holding an important place in underground coal mining and growing in use over time, it is important to develop and improve controls of the exhaust emissions, especially diesel particulate matter (DPM), to further reduce potential health hazards. The proper design and maintenance of diesel engines and on¬board control procedures are paramount requirements for controlling DPM successfully. There is also, however, a significant reduction potential in terms of personal exposure that can be realized by managing the DPM that gets into the airstream. Strategic design of the mining, ventilation, and equipment implementation systems remain essential for efficiently reducing the DPM concentrations.Modeling the effect of diesel exhaust contaminants upon the mine atmospheric quality will permit improved health and safety design of the overall mining and ventilation systems. Numerous studies have been performed to model the distribution/transport of gaseous and particulate emissions in the underground mine atmosphere and some very sophisticated convection/diffusion models have been developed (Skobunov, 1974; Thakur, 1974; Stefanko and Ramani, 1975; Wala, 1980; Bandopadhyay and Ramani, 1983). Most of these models were developed for a single airway or based on the assumption that the ventilation network of a mining section can be approximately represented by a single intake and a single return. The complexity of most models of the convection/diffusion type and the mobility aspect of diesel haulage units made a detailed emissions model very difficult to develop.The current model is an attempt to fill the need for a more generic tool applicable to mining sections employing multiple mobile diesel units by simplifying the convection-diffusion model to a convection-only model. The simplification is based on the fact that the diffusion coefficient will affect only the transient environmental contaminant concentrations with little or no affect on the time-weighted-average concentrations over a relatively long period such as a working shift (Lee et al., 1994). In view of the difficulties involved in mathematical modeling, the approach here is developing and using a computer simulation model. A PC-based FORTRAN 77 simulation model for the analysis of mining systems with multiple diesel sources and any ventilation network configuration was developed to study the distribution/transport of DPM in mine airways, evaluate methods of reducing DPM concentrations, and explore modifications to existing mining practice."

Dec 1, 1996

By H. H. Dewing

The Bureau of Mines conducted a laboratory-scale investigation of a technique that produces zinc sulfate and elemental sulfur from sphalerite concentrates by reaction with sulfuric acid at 175° to 200° C and ambient pressure. The objective of the investigation was to develop a hydrometallurgical method of producing zinc from sulfide concentrates that does not generate sulfur dioxide pollutants. Reaction with 80-to 85-pct sulfuric acid produced 4 moles of sulfur for every 3 moles of sphalerite reacted, with minimal production of sulfur gases under optimum conditions. More than 98 pct of the zinc was recovered as zinc sulfate after 3 hours at 175° C. The reaction mixture was leached with simulated spent zinc electrolyte containing 13-pct sulfuric acid to recover zinc sulfate from the insoluble, high-sulfur residue. Neutral zinc sulfate, which is required for electrolysis, was separated from the sulfuric acid solution by crystallization as ZnS04?7H20 at -10° C. Up to 80 pct of the water in the recycled electrolysis solution was removed by the crystallization process; evaporation was used to further concentrate the sulfuric acid for reuse in leaching sphalerite. Advantages of the proposed method over conven-tional roasting and leaching include virtual elimination of sulfur dioxide, production of a solid sulfur byproduct, and higher zinc recoveries due to elimination of zinc ferrite losses.

Jan 1, 1978

By Wing G. Agnew, John A. Johnson, McHenry Mosier

"INTRODUCTION AND CONCLUSIONSThe first three reports of investigations 5/ in this series, pertaining to the investigation of stemming at the Mount Weather Testing Adit dealt with the dust produced by blasting, the effect of stemming on gases generated by blasting, and the relative advantages and disadvantages of different types of stemming and no stemming when used with 60-percent ammonia gelatin dynamite.This report covers an investigation of the length of stemming material through which a primer will fire and detonate a charge of dynamite, such as a missed hole.The practice of drilling a new hole a foot from a missed hole to blast out the missed hole should be prohibited. It is dangerous, as is evidenced by the number of miners killed through drilling into missed holes. It is even more hazardous in a mine on a multiple-shift basis, in which the same miners do not drill succeeding rounds."

May 1, 1942

By Larry J. Nicks

The Bureau of Mines is investigating the catalytic activity of rare-earth compounds to develop a catalyst for the cathode reaction of a hydrogen-oxygen fuel cell. This report presents the results of studies of the catalytic activities of lanthanide oxides for the oxidation of hydrogen at 150° to 250° C. Preliminary activity tests were made with approximately stoichiometric mixtures of hydrogen and oxygen diluted with helium. A series of tests was also run under oxygen-rich conditions in which specific rate constants and activation energies were determined. Variations in rate constants up to 2,000 times were observed for the various lanthanide oxides. The three most active catalysts were oxides of Ce, Pr, and Eu, having specific activities of 6.93 X 10-7, 4.88 X 10-7, and 4.06 X 10-7 moles H2.sec-1.m-2, respectively, at 200° C.

Jan 1, 1973

By H. B. Cooke

In connection with its researches on the crude petroleums of the United States, the Bureau of Mines has made a particular study of apparatus for the distillation of hydrocarbon mixtures. While this study is still incomplete it has already resulted in the development of considerable laboratory and semi-plant equipment, motet of which has been described in various publications of the Bureau. The laboratory apparatus (Hempel distillation) and method gives satisfactory comparative results in the laboratory examination of crudes and have been found applicable to crudes of all types, but the agreement of laboratory and plant distillations is not as close as might be desired. This is due, in part, to limitations in size and construction of the laboratory apparatus. Some refiners claim that the Bureau of Mines' laboratory method (Hempel distillation3) for distilling crude petroleum, does not show the full gasoline content of the oil, while others have stated that it indicates more gasoline than can be obtained from the crude commercially. This difference of opinion among refiners results largely from the great variation in stills used and methods of operating them. The Bureau's experience has shown that crude oils from different fields vary widely in character; in fact, that it is not yet possible to classify crude's adequately on the basis of their Down chemical and physical characteristics. As a result of the differences that exist among crudes, and of the difficulty of designing refinery equipment, no standard practice has yet been adopted for the commercial distillation of petroleum, and ma" types of stills are used in the refineries of this country. Although many factors enter into the design of equipment and the development of commercial practice in refining of crude oil, there

Jan 1, 1924

Determine the minimum waterflow rate needed for effective control of dust produced by cutting machines used to mine water-soluble ores. Approach Conventional wet-bar cutting techniques were studied to evaluate their dust control performance, and the optimum water flow needed for dust suppression was determined. Wet-bar type cutting techniques are used to help control mine dust by keeping the cutting chain wet. As the chain cuts the kerf, it dampens the dust produced by the cutting action at the point of generation. The Bureau, under contract, evaluated three basic wet-bar techniques, as shown in the diagram: water-trickle system A uses a gravity-feed or low-pressure (less than 50 psi) pump to send water through the bar and to discharge it at the bar tip. Water-spray system B uses a low-pressure spray nozzle located at the front of the cutter head. For protection the nozzle can be located within the cutter

Jan 1, 1982

By R. W. Van Dolah

The feasibility of formulating cap-sensitive slurry explosives for use in underground mines with potentially flammable gas atmospheres was examined. Formulations containing aluminum metal as sensitizer and sodium chloride to reduce incendivity were prepared; some were cap-sensitive and had adequate air-gap. Flaked aluminum metal rather than the atomized type proved to be the more effective sensitizing agent of the formulations tested for incendivity in the large gallery of the Bureau of Mines, some were found to be suitably nonincendive.

Jan 1, 1968

By Christopher C. Jobes, N. Kumar Kittusamy, Alan G. Mayton, Dean H. Ambrose

Researchers with the National Institute for Occupational Safety and Health (NIOSH) conducted a systematic study to evaluate seat designs on low- and mid-coal-seam shuttle cars. The purpose was to gather additional data to support earlier findings that NIOSH seats, with unique viscoelastic foam padding, are indeed improved designs for coal mine shuttle cars. This study included a larger sample of shuttle car operators than a prior NIOSH investigation. Eight shuttle car operators participated in evaluating seat designs on the basis of perceived levels of vehicle jarring/jolting and discomfort. Researchers then compared the operators’ perceptions with field-measured levels of vehicle jarring/jolting. Seven seat designs were evaluated on low- and mid-coal-seam shuttle cars during production operations at two underground coal mines in southern West Virginia. These seat designs comprised the one already in use on each vehicle and five NIOSH designs. Experimental data were collected using accelerometers, signal conditioning amplifiers, and filters connected to a data recorder, whereas subjective data were gathered via a visual analog scale (VAS) and a questionnaire. Field trials included shuttle cars operating under full- and no-load conditions. VAS responses indicated that NIOSH-designed seats performed better relative to comfort and isolation from vehicle jarring/jolting than the existing seats used in the shuttle cars. Both mid- and low-coal-seam shuttle car operators, during no-load and full-load conditions, rated lower levels of jarring/jolting with the NIOSH seat design. Questionnaire responses indicated that shuttle car operators rated NIOSH seat designs as more comfortable. Vehicle operators most frequently suggested the addition of armrests as a way to improve the seats on the mid-seam shuttle car. The quantitative levels of vehicle jarring/jolting for the no-load condition (more severe condition for vehicle operation) showed that NIOSH seats for the mid-coal-seam shuttle car performed better than the existing seat in terms of peak acceleration and crest factor. Similarly, for the low-coal-seam shuttle car, NIOSH seats performed better than the existing seat in terms of peak acceleration, root-mean-square (RMS) acceleration, and crest factor.

Jan 11, 2006

By L. C. IlsLey

As part of its work for the improvement of safety conditions in mines , the Bureau of Mines has undertaken to establish a list of permissible storage - battery locomotives for use in gaseous mines , and , to this end , has issued Schedule 15 , "Procedure for Establishing a List of Permissible Storage -Battery Locomotives for Use in Gaseous Mines . " Up to the present time , two approvals * have been issued under this Schedule , and considerable testing work done on four other applications which have been made for approval . Prior to the publication of Schedule 15 , the Bureau conducted both field and laboratory investigations to determine the hazard from the batteries used in mine locomotives . ** These investigations indicated that the safety of the locomotive would depend largely on proper care of the battery , also on the use of a battery as mechanically rugged as possible . For this reason the Bureau staff , in testing locomotives submitted for approval , considered it advisable to subject the batteries to a jarring or bumping test to prove their adequacy as regards mechanical endurance and ruggedness . These tests on the batteries of the locomotives are described below.

May 1, 1922