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This report describes the activities and publications of the Bureau of Mines Health and Safety Research and Testing Center, Pittsburgh, Pa., for the fiscal years 1960-65. It includes a discussion or work being conducted on roof control, dust explosions, ventilation, health, coal mine fire control, and electrical-mechanical testing, and an abstract of each paper published during the report period.

Jan 1, 1966

By Frederick K. Allgaier

This is the first in a series of progress reports on the longwall subsidence research program at the Bureau of Mines Denver Research Center. As part of this program, the Bureau and the Utah Power and Light Co. are cooperating on a study conducted at the Deer Creek Mine, which is directed toward developing the capability to estimate the surface subsidence resulting from longwall mining in a geologic, topographic, and mining environment common to coalfields in the Western United States. A monitoring network has been established at the Deer Creek Mine to measure subsidence over four adjacent longwall panels. To date, two panels have been mined. Subsidence began as the first panel was mined and continued for 1 year following completion of the panel, during which time the adjacent panel was mined" A maximum of 2.7 feet of subsidence occurred over the two longwall panels mined at a depth of 1,500 feet. Because of the length of time that subsidence continued after mining, the final subsidence profiles and angle of draw have not yet been determined.

Jan 1, 1982

By B. W. Madsen

The Bureau of Mines conducted a large-scale (6.4 t), long-term (2,165 days) test to gain a better understanding of the leaching characteristics of chalcopyritic ores. An ore sample containing 0.77 pct Cu was leached in a fiberglass column by downward percolation of acidified ferric sulfate solutions. Three sets of leaching conditions were investigated: (1) ambient temperature leaching, (2) elevated temperature (50° to 60° C) leaching, and (3) elevated temperature leaching after inoculation with thermophilic bacteria. Leaching at ambient temperature resulted in a copper extraction rate of 0.44 pct per 100 days. Increasing the temperature to 50° to 60° C resulted in decreased activity of natural mesophilic bacteria, and the leaching rate decreased to 0.22 pct per 100 days. The pH was lowered from 2.0 to 1.6, and nutrient solutions that contained thermophilic bacteria were added. This procedure resulted in an increase in the ferric-to-ferrous iron ratio and an increase in the copper leaching rate. However, the increased leaching rate was not sustained, and 120 days after inoculation the bacterial activity declined, the ferrous iron content increased, and the copper leaching rate decreased.

Jan 1, 1983

By McClelland. John J.

This Bureau of Mines report discusses recent applications of water in-fusion technology to control dust in U.S coal mines and presents recommended guidelines for determining coal seam infusibility. The techniques required to use water infusion are presented in detail. A Bureau case study indicated that water infusion reduced dust levels by 68 pct along a longwall plow face, bringing this section into compliance with the Z.0-mg/m3 Federal dust standard. Similar studies conducted by Occidental Research Corp. under a Bureau contract show water infusion at two longwall double-drum shearer operations produced dust reductions ranging from 38 to 50 pct. Water infusion was found to be cost effective, aver-aging 5 cents per ton.

Jan 1, 1987

By R. E. Siemens

The Bureau of Mines sought to correlate the variation of structure-sensitive superconducting properties with microstructure in selected Cb-Hf alloys and to compare the experimental results with those predicted by the GLAG theory. Alloys in wire and rod form were evaluated by critical temperature, critical current, magnetization, resistivity measurements, and optical and electron microscopy. In the absence of an external magnetic field, the current carrying capacity of columbium was greatly reduced with addition of up to 85 wt pct Hf, but a large increase in Ic occurred for Cb-90 wt pct Hf. Favorable Ic-H behavior was observed in cold-drawn alloys containing 25 and 57 wt pct Hf. Correspondingly, a maximum in Tc occurred at 10-25 and 90 wt pct Hf. Four- or five-hour heat treatment at 600° C resulted in maximum Ic values and maximum hysteresis in magnetization. Dislocation pileup, polygonization, and fine precipitates, responsible for flux pinning, are listed in order of their effectiveness as pinning sites. Sites having an average separation of 1,500 to 3,000 A and a diameter of 1,000 A or less were most effective in influencing Ic-H and M-H behavior. The resistive critical fields increased smoothly to a maximum of 80 k0e between 60 and 65 wt pct Hf. Highfield, mixed state, reversible paramagnetism was observed in some alloys; however, the GLAG theory was in good agreement with experimental results for the majority of the composition range studied.

Jan 1, 1969

By H. M. Thorne

Oil shale, a potential source of products presently obtained from petroleum, is found in many countries. The most extensive known deposits from the standpoint of potential shale oil in place are those in Brazil and the United States of America. Mining methods used for oil shale range from open-pit operations for shallow deposits to room-and-pillar and longwall techniques for deposits with thick overburdens. Oil shales from different sources vary greatly in the amounts and types of organic and inorganic constituents. By retorting, the organic material is converted to oil, gas, and coke. The largest percentages of oil are obtained from materials having the highest hydrogen content. Over 2,000 retorting systems have been patented, but only a few have been used industrially, and no single process seems best for all types of shales or economic conditions. Shale oils have different characteristics, depending on the source rock and method of retorting. They contain large quantities of olefinic hydrocarbons and more oxygen, nitrogen, and sulfur derivatives of hydrocarbons than most petroleums. Consequently, petroleum refining methods usually must be modified for shale oil. This is particularly true in catalytic processing. Hydrogenation, even under mild conditions, improves shale-oil refinability. Several byproducts may be obtained from both the retorting and refining steps,

Jan 1, 1964

By A. B. Hooker

A list of permissible mine equipment approved by the Bureau of Mines prior to January 1, 1940, was published as Information Circular 7207.3 Three supplements published as I. C. 7240,4 I. c. 7283,2/ and I. C. 73166/ completed the list of equipment available to January 1, 1945. The present list is a revision of the previous lists, together with the additional equip- ment approved from January 1, 1945, to January 1, 1947. In preparing this list, certain items have been omitted, either because the manufacturer is no longer in business or manufacture was discontinued several years ago. However, some discontinued equipments that are still in service and for which repair parts are available are marked with an asterisk to indicate their limited status. The remaining obsolete equipments are listed in tabular form in Appendix 1. Appendix 2 lists seven satisfactory fuels available for use in permissi- ble flame safety lamps and shows where the fuels are available. The equipments listed were approved only when inspection and tests showed that they met the minimum standards of safety as outlined in "schedules" based upon laboratory tests as well as on performance underground. This circular is published so that users and potential users may be in- formed of the many types of permissible equipment available for reducing hazards incidental to coal mining and as an aid in identifying the equipments.

Dec 1, 1947

By Joseph Coffman

There are 14 operations that supply 97% of the Market Economy Country (MEC) manganese and contain nearly all of its resources. Six mines account for about 70% of the production and 85% of the resources; there are no known resources that are economically close to those that are currently being mined. Costs (January 1989 dollars) of producing manganese concentrates from the operations evaluated are estimated to range from $ 0.96 to $ 1.86 per long ton unit (ltu or 22.4 lb) of contained manganese. Total MEC demonstrated resources evaluated amount to about 1.2 billion tons of in situ ore containing 474 million tons of manganese. Identified resources amount to about 1.8 billion tons of in situ material. Key results of the study indicate the following: 1. The MEC supply of manganese will be from the currently mined resources well into the next century. 2. Centrally Planned Economy Countries (CPEC's) will be increasingly dependent on MEC manganese ore and concentrate in the future. 3. At the 1976 to 1987 demand increase rate, total MEC resource needed through the year 2000 would be about 282 million tons of in situ material. 4. Transportation and infrastructure support will continue to be major elements of production costs.

Jan 1, 1992

By Alan R. Buehler

The Bureau of Mines conducted a mineral investigation of the 10,500-hectare Cache Peak study area in 1992; the area had been proposed as wilderness. Bureau personnel examined and sampled prospect workings; 14 rock and 20 placer samples were taken during the investigation. The study area is centered about 40 km south-southeast of Burley. Idaho, in the Sawtooth National Forest. There were seven mining claims located inside the study area, and one additional historical mining claim location. Gold, silver, copper, lead, zinc: Possible resource, poor exposure precludes estimate. Marble: Several million tonnes may be suitable for a variety of uses; markets too distant to favor mining. Sand and Gravel: Several million m3, but markets and transportation costs do not favor mining. Quartzite: Several million tonnes may be suitable for metallurgical purposes; however, markets are too limited to mine. Slabs have been quarried at three localities adjacent to the study area, for decorative stone. Production: In 1979, two tonnes of ore were produced and a plan of operations was submitted calling for approximately 5 km of access road for the Last Chance mine. Decorative stone production was not recorded.

Jan 1, 1993

By B. R. Mohal, F. F. Aplan, S. Chander

"The wetting behavior of coal has been determined in the presence of nonyl and octyl series of nonionic surfactants containing polyethoxy groups of different sizes. The wetting behavior was determined by a modified Walker technique and contact angle measurements. The results show that the wetting rate of coal varies with coal rank, structure of the hydrocarbon chain and number of ethoxy groups in the hydrophilic group of the surfactant. A close relationship has been observed between the wetting rates and the short-time advancing contact angles.INTRODUCTIONNonionic surfactants are used in many applications to improve wettability of solids. They can be used as dispersing agents [ 1 ] or dust suppressants [ 2-5] and to control the flotation, flocculation, filtration and, flowability of particulates. This study was undertaken to study the effect of a series of nonionic surfactants on the wetting behavior of coal. Two series of surfactants, namely, ethoxylated nonyl and octyl phenols were used. The nonyl phenol series con tains a linear hydrocarbon chain containing nine carbon atoms (CH3 ( CH2 )8-C6H4- ( OC2H4 ) n, where n is the number of ethoxy groups) . The octyl phenol series contains a branched hydrocarbon chain containing eight' carbon atoms ( ( CH3 ) 3CCH2C ( CH3) 2-C6H4- ( OC2H4 ) n ).Initial wetting rates — modified Walker techniqueWalker et al. [ 6 ] developed a sink test to determine the wettability of coal particles. In this technique, coal particles are dropped individually onto the surface of surfactant solutions of different concentrations, and the most dilute concentration in which coal would sink ""instantaneously"" is determine& This technique is a variation of a procedure initially developed by Draves and Clarkson [ 7 ] to determine the effect of surfactants on wettability of cotton fibers."

Jan 1, 1989

By R. A. Guereco

Accurate measurements of physical dimensions of a section of stainless steel capillary tubing are presented and used to develop two final working equations for an absolute gas viscosimeter. The effects of pressure and temperature on these dimensions are considered. The internal surface finish and nonuniformity of the capillary bore are discussed, as well as entrance, kinetic energy, gas slippage, and gas compressibility correction factors.

Jan 1, 1967

By O. C. Blade

This report is one of a series made by the Bureau of Mines under a cooperative agreement with the American Petroleum Institute on the characteristics of commercial aviation gasolines. The series of Surveys is a continuation of like work conducted under aimil.ar cooperative agreements with the Coordinating Research Council, Inc. by the National. Bureau of Standards from 1940 through 1946 and by the Bureau of Mines from 1947 through 1949. A completed list of the series of surveys is given at the end of this paper.

Jan 1, 1951

By A. J. Kraemer

The properties of crude petroleum continue to interest the Bureau of Mines and constitute an important phase of its major studies on the mineral resources of the United States. The Bureau's interest in the subject has been intensified by frequent requests for information on the characteristics of crude petroleum from various producing fields. Since its inception the Bureau of Mines has collected and analyzed samples of typical oils and at present has surveyed and classified crude petroleums from nearly all the known oil fields of the Western Hemisphere. Results of these surveys have been presented in various Bureau of Mines publications. (See bibliography, appendix A, p. 145.) The nature and comparative value of crude oils from various countries and the extent to which these oils may be considered potential competitors for markets are of manifest importance to the petroleum industry in all lands, largely because all crude oils, wherever produced, are either actual or potential competitors for a market with all other crude oils. The numerous discussions of foreign production of oil that have appeared in the technical press in the past indicate the great interest of the United States in this subject.

Jan 1, 1937

By R. V. Higgins

The results of two separate but related studies are given. In the first study, four equations were tested; the object was to determine which would produce a curve that would best fit data points that represent a trend of declining oil production in 90 California fields. Two conventional equations (the Arps and semilog) and two novel equations (extreme-c and double semilog) were tested. The curves were first fitted to the initial 9 years of the 15-year production data and then extrapolated for 6 years to determine how well the extrapolated curve would fit the data points. The generated curves were also extrapolated beyond the last data point to predict rates of future production. The results of the first study showed that no equation was clearly superior to the others in all respects. The semilog equation resulted in the best fit to production data for the first 9 years, but the Arps and extreme-c equations produced a better fit for the extrapolated data for the period of 9 to 15 years. The Arps and extreme-c also gave more realistic production rates when extended to the point where cumulative production equaled reserves. A second study was made to determine if the least-squares technique applied to the Arps equation would result in more accurate extrapolations. The merits of the logarithmic and the nonlogarithmic forms of the Arps hyperbolic equation were also tested. For the logarithmic expression, it was found that one of the constants of the Arps equation reached a value so small or so large that the equation was not applicable to the data of 40 of the 90 California fields. The nonlogarithmic form of the Arps equation was applicable to neither the same 40 fields nor to a few additional ones. When the data and the Arps equation were compatible, the use of the least-squares technique as compared with other methods improved the extrapolation accuracy somewhat.

Jan 1, 1971

By Arden D. Fugate

This work was conducted to determine a feasible process for converting siliceous fluoride offgases to a commercially usable product. The offgases were generated by pyrohydrolytic defluorination of low-grade fluorspar in a gas-fired rotary kiln, and fluorine was collected as a hydrofluoric-fluosilicic acid. A silicon-free fluoride solution for further processing was then produced by neutralizing the acidic scrubber solution with anhydrous ammonia, silicon being separated as orthosilicic acid. Ninety to ninety-nine percent of the fluorine originally present remained in solution as ammonium fluoride. Silicon was also separated from synthetic fluosilicic acids, having F-to-Si weight ratios ranging from 3.50 to 14.3. The solutions below a ratio of 4.06, the F-to-Si ratio of H2SiF6, containing dissolved silicon were desiliconized as completely as those containing less than the stoichiometric quantity of silicon. An electrolytic-grade cryolite was recovered from the ammonium fluoride solution by reacting with either sodium aluminate or alumina trihydrate and sodium hydroxide. A product containing 97 to 100 percent of the fluorine, represented by Na3A1F6, was recovered, and 94 to 99 percent of the theoretical yield was realized.

Jan 1, 1963

By John J. Mulligan

The creeks draining Cape Mountain, on the western tip of Seward Peninsula, Alaska, comprise the Cape Mountain tin-placer district. Because of the war-caused shortage of tin, the Bureau of Mines in 1943 conducted a churn-drill placer reconnaissance to explore the district. Favorable indications were found, and plans were made for further investigation of the deposits; the plans were abandoned when tin again became plentiful. In July 1951 the Zenda Gold Mining Co. was granted a Defense Minerals Administration (Defense Minerals Exploration Administration after October 1951) loan to continue exploration of the more favorable areas indicated by results of the Bureau's investigation. Equipment was moved to the area in the fall and winter of 1951-52. During the 1952 field season, 209 churn-drill holes totaling 7,521 linear feet and 10 test shafts totaling 96 linear feet were sunk on the Cape Creek drainage. Work was resumed in 1953, when 56 churn-drill holes totaling 3,157 linear feet were drilled on Boulder Creek. The company planned to drill Goodwin Gulch and Goodwin Creek, but no further work was done owing to lack of capital.

Jan 1, 1959

By O. C. Blade

The use of Diesel fuel as a source of power is continuing to increase in the United States. The latest available figures indicate that refineries are delivering in excess of 10,000,000 barrels of this type of fuel per month. Factors contributing to this increased consumption are conversions by a number of railroads from steam to Diesel locomotives and the growing use of Diesel engines in buses, trucks, tractors, earth-moving machinery, water craft, and stationary power plants. The increasing importance of Diesel fuel has led to a need for more information on its characteristics, particularly on the grades and qualities currently being marketed. To supply this information the American Petroleum Institute and the Bureau of Mines, United States Department of the Interior, under a cooperative agreement, are conducting annual surveys of Diesel fuels produced in refineries in this country. Samples of Diesel fuel were analyzed by the manufacturers in accordance with instructions from the Motor-Fuels Survey Panel of the Automotive Research Committee of the American Petroleum Institute. Results of the analyses were transmitted to the Bureau of Mines where the data were studied am compiled as shown in the tables of this report. The first survey was made in 1950 and was published as a Bureau of Mines report. The present report shows the results of a similar survey made during 1951.

Jan 1, 1951

By V. R. Miller

The Bureau of Mines conducted research on substitute brazing filler alloys with properties similar to those of silver filler alloys in an effort to conserve silver and reduce hazards from cadmium emissions. Experimental work was conducted first on the commercial silver brazing alloys BAg-I, BAg-la, BAg-2, and BAg-3 to establish criteria for evalu-ating the substitute alloys. Properties investigated included the wettability of copper, brass, and steel substrates, and the strength of joints made with the filler alloys. A series of experimental alloys containing 50 to 60 pct Cu, 20 to 28 pct Mn, and 17 to 30 pct Zn was prepared and evaluated, together with Cu-Mn-Zn alloys with 5 pct Pb or 2 pct Ni. Wetting properties and joint strengths were not as good as those for silver filler alloys, and the high application temperatures reduced the copper and brass base metal strengths. However, experimental alloys containing 70 pct Cu, 15 to 20 pct Mn, and 10 to 16 pct Sn had wetting and strength properties approaching those of the silver filler alloys. The application temperatures for these alloys were high-er than those for silver fillers, but not as high as those for the Cu-Mn-Zn alloys. With the Cu-Mn-Sn alloy fillers, copper alloy joint members are less deteriorated by recrystallization than when applying Cu-Mn-Zn alloys. The Cu-Mn-Sn system has potential for further devel-opment as a substitute brazing alloy system, particularly if the melting temperature can be reduced by the addition of other elements without decreasing the ductility and wetting.

Jan 1, 1983

By R. R. McLellan

The Brown Derby pegmatites are in Gunnison County, Colo., about 18 miles east of Gunnison. Approximately 860 tons of lepidolite concentrates, with smaller amounts of microlite and beryl, was produced from 3 dikes of the Brown Derby group from 1943 through 1947. No mining was done from 1948 until December 1950, when production of lepidolite and beryl was resumed by the Poston Mining & Milling Co. Mining was intermittent during 1951 and 1952. The dikes were mapped and studied by the Federal Geological Survey during the field seasons of 1942 to 1944, and in May 1950 the Bureau of Mines initiated a diamond-drilling project to test the three dikes for lepidolite and beryl. After being recessed twice, the project was terminated indefinitely July 1951. Seven drill holes were completed for a total of 1,841.6 feet of drilling.

Jan 1, 1956

By W. H. Oppelt

A small, annular-retort gasifier having a nominal capacity of 40 pounds of lignite per hour was designed and constructed at the Lignite Experiment Station, Grand Forks, N. Dak. The purpose of the investigation was to increase the capacity of an annular-retort gasifier by better temperature distribution in the heating chamber (adjacent to the annulus) and by supplemental internal heating with controlled amounts of air. Correct control of air admission should yield crude ammonia-synthesis gas having a (H2+CO)-N2 ratio of 3. Dakota Star stoker-size lignite was used during the exploratory experimental program. The effects of temperature level and distribution in the heating chamber and of addition of air to the reactor were investigated. Hydrogen - carbon monoxide ratios ranged from 1.9 to 2.5, and (H2+C0)-N2 ratios were as low as 2.9. Hourly gas production ranged from 970 to 2,580 cu. ft., or 62.0 to 164 cu. ft. per sq. ft. of heated surface, or 350 to 940 cu. ft. per cu. ft. of reactor volume. Data from the small gasifier could be readily correlated with those previously obtained in the commercial-scale unit under comparable experimental conditions.

Jan 1, 1957