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By A. G. Smelley

As part of research conducted in its mission to effect pollution abatement, the Bureau of Mines, U. S. Department of the Interior, is developing a dewatering technique that allows for disposal of phosphatic clay wastes, for reuse of water now lost with clays, and for reclamation of mined land. The technique utilizes a high-molecular-weightnonionic polyethylene oxide polymer (PEO) that has the ability to flocculate and dewater phosphatic clay wastes. A synergistic flocculation study was made to determine whether a portion of PEO could be replaced by other reagents. Several groups of reagents were tested: (1) those that increased the zeta potential of the phosphatic clay wastes; (2) those capable of hydrogen bonding; and (3) those which flocculated the phosphatic clay waste. Reduction in PEO consumption occurred only with addition of those reagents able to flocculate the slime. The use of natural guar gums resulted in a lower PEO requirement and also yielded a dewatered product of higher solids content, 43 to 45 percent, versus 33 to 35 percent obtained with PEO alone.

Jan 1, 1980

By Wilber Duvall, Leonard Obert

"INTRODUCTION This report is the first of four to be presented on the microseismic method 4/ of predicting rock failure in underground mining. The application of the microseismic method to one specific case, namely, that of predicting rock bursts in deep mining, has been described in two previous reports. 5/ 6/ Since the publication of these reports 5/ 6/ the method has been extended to other fields of mining, end it is the purpose of this report (Part I) to describe the general microseismic method, giving the empirical facts upon it is based, the different testing procedures, the method of recording and analzing the data, and the interpretations that can be obtained there-from. Part II will describe a series of laboratory experiments that were performed to give information on the origin of microceismims and the microseismic properties of various rocks. Part III will cover application of the method to specific mining problems together with a brief description of a number of investigations performed during, the last three years. Part IV will describe in detail the microseicmic equipment used in the various phases of these investigations."

Feb 1, 1945

By Gregory M. Molinda

The Coal Mine Roof Rating (CMRR) was developed 10 years ago to fill the gap between geologic characterization and engineering design. It combines many years of geologic studies in underground coal mines with world-wide experience with rock mass classification systems. Like other classification systems, the CMRR begins with the premise that the structural competence of mine roof rock is determined mainly by the discontinuities that weaken the rock fabric. However, the CMRR is specifically designed for bedded coal measure rock. Since its introduction, the CMRR has been incorporated into many aspects of mine planning, including longwall pillar design, roof support selection, feasibility studies, extended-cut evaluation, and others. It has also become truly inter-national, with involvement in mine designs and funded research projects in South Africa, Canada, and Australia. This paper discusses the sources used in developing the CMRR, describes the CMRR data collection and calculation procedures, and briefly presents a number of practical mining applications in which the CMRR has played a prominent role.

Jan 5, 2007

By Edward Cogan

Equilibrium phase diagram studies of zirconium- rare earth metal alloys by the Bureau of Mines at its Albany Metallurgy Research Center prompted the development of a rapid gravimetric method for determining rare earths in zirconium in which the rare earths are absorbed from sulfuric acid solution of the alloy on a cation exchange resin . The sample in 10 percent H2SO4 is introduced into the column , the zirconium is eluted with 10 percent H2SO4 , and the rare earths are eluted with (NH4 )2SO4 solution and precipitated with NH4OH . A tracer technique was employed to determine the efficiency of the procedure . Y203 and europium 154 - 152 (Oak Ridge ) were added to 10 g of zirconium and taken through the entire procedure . Recovery averaged 97.6 percent on 0.002 μg europium in the rare earth fraction . Rare earths were determined in the range 0.10 to 90 percent .

Jan 1, 1964

By L. A. Haas

Hydrogen sulfide was decomposed to elemental sulfur in an electrical discharge. With He, N., or Ar diluents, a threshold voltage between 1 and 3 kV was required for the decomposition reaction to occur in a laboratory ozonizer. Above the threshold voltage, the HAS decomposition rate increased with increasing voltage, but the increase was more pronounced with argon diluent than with either nitrogen or helium. In common with other reactions in an electrical discharge, the B2S decomposition decreased with increasing temperature in the range of -410 to +61° C. The reaction did not appear to be rate-controlled by a solid-gas sorption step because the introduction of activated charcoal into the electrical discharge zone did not significantly affect the decomposition yield. In the presence of polymeric chlorofluoro-carbon oil, 90 pct conversion of the 3 pct H2S in helium was obtained at 14 kV, 60 Hz, a 2-mm electrode gap, and a gas-residence time greater than 1 min. Under the same experimental conditions in the absence of oil, the conversion was only about 50 pct.

Jan 1, 1973

By A. Dale Marcy, Pamela L. Drake

Workers who perform routine welding tasks are potentially exposed to fume that may contain manganese. Manganese may cause respiratory problems and is implicated in causing the occurrence of Parkinson-like symptoms. In this study, a field colorimetric method for extracting and measuring manganese in welding fume was developed. The method uses ultrasonic extraction with an acidic hydrogen peroxide solution to extract welding fume collected on polyvinyl chloride filters. Commercially available pre-packaged reagents are used to produce a colored solution, created by a reaction of manganese(II) with 1-(2-pyridylazo)-2-naphthol. Absorbance measurements are then made using a portable spectrophotometer. The method detection limit and limit of quantification (LOQ) were 5.2 mg filter-1 and 17 mg filter-1, respectively, with a dynamic range up to 400 mg filter-1. When the results are above the LOQ for the colorimetric method, the manganese masses are equivalent to those measured by the International Organization for Standardization Method 15202-2, which employs a strong acid digestion and analysis using inductively coupled plasma-optical emission spectrometry.

By Charles E. Whieldon

The importance of recovering more oil from known petroleum reserves has placed increased emphasis on the application of secondary-recovery methods. It is hoped that these reports will stimulate interest in improved waterflooding techniques, thereby discouraging premature abandonment of oil leases. A previously published report4/ described the highly successful results of waterflooding in the Weir sand in eastern Kentucky. A more recent report5/ evaluated the results of waterflooding in Roane County, W. Va. (See fig. 1.) Two waterflooding projects have been operated in Pleasants County, W. Va. (fig. 2), one by the Dearborn Oil & Gas Corp. in the Cow Run sand near Calcutta, McKim and Washington districts, and the other by George C. Schoonmaker in the Maxton sand at Bens Run, Union district. This report report describes the waterflood operation near Calcutta, W. Va.

Jan 1, 1960

Reduce the number of accidents in which large mining trucks crush objects that were not visible to the driver. Approach Improved rear view mirrors, light-bending plastic lenses, and a closed circuit TV, are combined in a rugged system that allows the driver to see almost all areas around a large raining truck. How It Works Improved mirrors, used in place of ordinary left and right rear view mirrors, give wider angle viewing. Fresnel lenses, two mounted on the front edge of the hood and another one mounted above the right front fender, show objects close to the front and right side of the truck. A rugged closed circuit TV camera mounted above the rear axle reveals objects behind the truck. See diagrams showing reduction of blind area around a 150-ton mining truck. The improved mirrors for rear viewing are approximately rectangular. The left rear view mirror has a flat reflecting surface 10 inches wide by 20 inches high. The right rear view mirror is curved to give wider viewing angles, both from left to right and up and down. This mirror is 12 inches wide by 16 inches high. Its convex reflecting surface has the same curve as the surface

Jan 1, 1979

By R. K. Franklin, S. T. Reese, J. J. Forbes

"INTRODUCTION It is a recognized fact that in the coal-mining industry coal dust must be allayed to promote the safety and health of underground workers. The Bureau of Mines has been cognizant of the hazards of coal dust for many years, and the necessity of controlling such dust was acknowledged when the Federal Mine Safety Code was formulated. Accumulations of coal dust increase the explosion hazard in a bituminous-coal mine and facilitate the propagation of an explosion. Some of the coal dust produced in mining is inhaled by the workers and contributes to respiratory infection. Impairment of vision and personal discomfort resulting from working in dense clouds of coal dust reflect unfavorably on the efficiency of workmen. Considerable coal dust, originating at the working face, is carried in the ventilating current and deposited elsewhere in the mine, thereby increasing the explosion hazard. It is apparent, therefore, that if coal dust could be allayed effectively at its points of origin, the dust-explosion hazard in bituminous-coal mines would be reduced greatly.Although dust control is practiced in many bituminous-coal and lignite mines, the extent and effectiveness of control for the, entire industry-is not generally known. The purpose of this circular is to present such information clearly, and to encourage coal-mine operators to install dust- allaying equipment.Factual data on dust-allaying practices at working faces in a large number of the bituminous-coal and lignite mines in the United States were .compiled from reports on recent Federal inspections of these mines, The information is presented in tabular form to permit review of the dust-allaying practices of a substantial part of the industry, by States, and also according to employment, and loading practice."

May 1, 1950

By Oliver Bowles

Sandstone, a widely distributed siliceous sedimentary rock, is the third most popular building stone in the United States. It is formed by the breaking down of preexisting rocks by weathering, subsequent segregation of the detrital quartz grains into discrete deposits by the sorting action of water or wind, and finally cementation of the quartz sand into a coherent rock. The homogeneity and resistance to weathering of the resultant sandstone make it suitable for exterior construction. Its excellent wearing properties explain its popularity for flagging and stair treads. However, quarrying and dressing methods and costs are adversely affected by the abrasiveness and hardness of sandstone especially as compared to limestone.

Jan 1, 1963

By Leonard Obert

This report describes the development of a dynamic strain gage and a companion amplifier and recording camera -an apparatus designed to pick up and record the strain waves produced in rock by a nearby explosion. Also included in the report is a discussion of the relationships connecting the strain with the displacement, velocity, and acceleration for both plane and spherical waves. The proposed tests for which the strain gages were intended required making measurements in solid rock, a factor that necessitated the development of a gage that could be inserted and anchored in a small-diameter diamond-drill hole. The restriction on the diameter of the drill hole is required so that the presence of the hole in the medium will not influence the propagation of the strain wave. The gage should respond with fidelity to the frequencies present in a wave pulse generated by the nearby detonation of a small quantity of high-velocity explosive. Preliminary tests showed that this frequency range extends from 200 to 10,000 c.p.s. or greater. Also, the gage should be capable of measuring strains ranging from a few micro-inches per inch to several thousand micro-inches per inch. Other desirable design specifications included a low gage output impedance to permit the use of long cables, and a low gage cost, particularly in view of the fact that for the final design none of the gages can be recovered from the medium.

Jan 1, 1949

By Dwight L. Sawyer

To provide technology that can help decrease the dependence of the U.S. aluminum industry on imported bauxite, the main ore of aluminum, the Bureau of Mines is investigating the extraction of aluminum from abundant domestic reserves of kaolinitic clay. Miniplant studies of the continuous leaching of calcined kaolin with boiling 25-pct HC1 acid resulted in a 93- to 99-pct extraction of the acid-soluble alumina in the calcined kaolin feed. Data are presented for an acid leaching study carried out in three or four continuously stirred tank reactors (CSTR) in series, feed rates of 100 to 250 lb/hr of calcined kaolin, and total nominal residence times of 0.7 to 2.3 hr. A material balance for a 176-lb/hr calcined kaolin feed rate in a circuit consisting of three reactors, four classifiers, and five thickeners is given. Data provide detailed compositional and physical information for calcined kaolin, process liquors, and acid-leached residue solids.

Jan 1, 1983

By G. R. Hopkins

A fifth successive record in fuel efficiency was established by the petroleum-refining industry in 1937, when the average heat requirement per barrel of crude oil run to stills was 554,000 3. t. u. compared with 597,000 3. t. u. in 1936. These amounts represent roughly the heat ob¬tainable from a tenth of a barrel of fuel oil (see fig. 1). Innumerable factors can influence heat consumption at rep aeries, but only a few are important enough to be subject to statistical measurement. Foremost of these is the ratio of runs to capacity, it being generally recognized that because the fuel demands for other than stills are comparatively inelastic, total heat requirements do not increase in direct proportion to crude runs. Thus, in 1937, crude runs of 1,183,440,000 barrels wore 11 percent higher than in 1930; the average operating ratio was 93 percent compared with 79 percent in 1936; but the total heat requirement increased only 4 percent, or from 639,149 billion 3. t. u. in 1936 to 663,966 billion 3. t. u. in 1937.

Jan 1, 1938

By M. P. Dalton

This paper which describes the milling practice at the Morning concentrator of the Federal Mining and Smelting Co., Mullan, Idaho, is one of a series being prepared by the Bureau of Mines. ACKNOWLEDGMENT The author wishes to acknowledge the assistance given by H. G. Washburn, general manager of the Federal Mining and Smelting Co., and by C. S. Price, assistant mill superintendent, in the preparation of this paper.

Jan 1, 1932

By George A. Bell

This paper reviewing the leaching practice of the New Cornelia mines of the Calumet & Arizona Mining Co. at Ajo, Ariz., is the first of a series being prepared by the Bureau of Mines on leaching methods and costs in the various mining districts. ACKNOWLEDGMENTS The author acknowledges the assistance of T. G. Chapman, consulting engineer, and E. D. Gardner, supervising engineer of the Southwest Experiment Station, Bureau of Mines, Tucson, Ariz.

Jan 1, 1930

By Edward D. Thimons

A remote-actuated stench gas fire-warning system has been designed and tested by the Bureau of Mines. This system makes use of the hard-wire network for the mine's phone pager system, thus greatly reducing the system cost. By locating stench gas canisters with remote-actuation release capabilities near working sections, the fire-warning time can be greatly reduced. In a test of the system in a Missouri lead mine, the time required to warn miners of a fire at two working faces was reduced from about 20min with the conventional system to less than 4 min with the remote-actuated system.

Jan 1, 1984

By Warren E. Morrison

The continuing high-level performance of the domestic mineral and mineral fuels industries during 1966 was sustained by the longest business upturn in the Nation's history. Spurred by consumer demand at home and the defense production requirements of the Viet-Nam war, the rising trend of economic activity during the year was reflected in the upward movements of the major economic indicators. At yearend the gross national product (GNP), representing the value of all goods and services produced, stood at $740 billion, $58 billion greater than in 1965. Corrected for price changes, the real value of GNP in terms of 1958 dollars was $648 billion and represented an annual increase in economic activity of 5.4 percent. Some 74 million persons were employed during the year out of a total population of 196.8 million, while unemployment fell below 4 percent. The Federal Reserve Index of Industrial Production averaged 156 for 1966, up 13 points from the previous year. However a jarring note in the 1966 expansion, and one which affected the mineral industries in particular, was the increasing pressure on prices and the threat of inflation. From 1961-65 economic growth was facilitated by relatively stable wages and prices and only mild inflation. During the period average wholesale prices hardly moved while average consumer prices rose only about I percent per year. But this long run of relative price stability ended during 1966 when consumer prices rose 2.9 percent and wholesale prices were up 3.2 percent from the previous year.

Jan 1, 1967

By W. E. Wallace, S. -G. Xing, M. J. Keane, J. C. Harrison

"SummaryDiesel-exhaust particles from two sources were dispersed in aqueous mixtures of dipalmitoyl phosphatidyl choline, a major component of pulmonary surfactant, and were tested for genotoxicity. Diesel samples from the same sources were extracted with dichloromethane and transferred into dimethyl sulfoxide and subjected to the same assays. Both types of extractions yielded similar results in both the Salmonella mutagenicity assay and the sister-chromatid exchange assay using V79 cells. After separation of the samples into supernatant and sediment fractions, the activity of both diesel samples was shown to reside exclusively in the supernatant fraction for the solvent-extracted samples, and exclusively in the sedimented fraction for surfactant dispersed samples. These findings indicate that genotoxic activity associated with diesel particles inhaled into the lung may be made bioavailable by virtue of the solubilization / dispersion properties of pulmonary surfactant components.While diesel engine emissions are associated primarily with transportation, they are also very common in the workplace. Estimates for the U.S. are that as many as 1.35 million workers in as many as 80 000 workplaces are exposed to the combustion products of diesel engines (NIOSH, 1988). These occupations include, but are not limited to mining, agriculture, motor vehicle maintenance, fork lift truck driving, truck driving, and tunnel and bridge operation."

Mar 1, 1992

By Terry J. Close

The Gates of the Mountains Wilderness study area is underlain by intrusive and sedimentary rocks, mainly limestone. No limestone has been produced from the study area; suitable material is more readily available elsewhere. Small amounts of gold, sapphires, and corundum were produced from a placer deposit along the banks of the Missouri River. The remaining gravel contains low mineral values. Other alluvial deposits along the Missouri River and Beaver Creek contain no identified economic resources other than sand and gravel. Some deposits could provide suitable construction material for local use.

Jan 1, 1984

By Thomas Varley

"During the past few years, since flotation has become the paramount treatment method for most all kinds of ores, the Bureau has gathered the data on consumption of reagents used in the flotation treatment. The first report was issued in 1916. A brief review of such reports shows the progress made in the art of flotation, and each year brings forth development of new reagents or combinations of reagents that seem sure to survive, but research and progress spell their defeat, if not by entire elimination, at least subjects them to considerable modification. Fortunately, close cooperation between the Bureau and the operators has been the means of an exchange of ideas in research work, and the development, in plant practice, of such research work on a commercial basis, is one of the outstanding features in milling today.In past years flotation has been referred to generally as ""oil flotation""— today it might be more properly called ""chemical flotatioin"" Minerals can be floated today without oil. Chemicals alone will do the work, showing how little was truly known about the process heretofore. The term ""regents as used herein, includes both chemicals and oils. The total pounds of oils and reagents consumed during the year was greater than shown in the 1925 report. The 1926 total was 201,711,795 pounds as compared with 81,688,967 pounds for 1925. The equivalent in pounds of reagent use& per ton of ore for 1926 was 3.933 as compared with 1.7972 for 1925. This increase is due largely to the amount of lime which is added in the alkaline circuits particularly in the mills treating coppers ores, which accounts for the larger tonnages."

Jan 1, 1928