Search Documents

By John B. Shutack

In an effort to improve the performance of the explosive-anchored rock bolt, the Bureau of Mines studied the effect of the detonation velocity of the explosive and type of charge (linear or nonlinear) on the fracturing tendency of the anchor tube. Also, different types of tubing were compared to determine the one most suitable for use as an anchor tube. The Bruceton up-and-down method was applied in tests in which steel shooting blocks having boreholes ranging from 1-3/8 to 2-1/8 inches in diameter were used. Of the four types of tubing evaluated, a welded A-178 tubing that was drawn over a mandrel and renormalized gave the most promising results. The A-179 seamless tubing that is normally used with the explosive bolt was the most inferior. Both types, however, gave significantly better anchorage than the conventional shell when tested in both laboratory and underground experiments. Within the range of velocities studied (5,000 to 7,000 m/sec), the type of explosive showed no significant effect on anchor-tube performance. In general; linear explosive charges provided better anchorage than nonlinear charges.

Jan 1, 1968

The Mine Safety and Health Administration (MSHA) defines an independent contractor as any person, partnership, corporation, subsidiary of a corporation, firm, association or other organization that contracts to perform services or construction at a mine. Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Jan 1, 2008

By Ivan F. Avery

DOMESTIC production of carbon black increased 4 percent in 1962 to 2,056 million pounds. Furnace black output was 8 percent, or 132 million pounds, above that in 1961 and accounted for 90 percent of total carbon black production. Channel black output continued to decline and was 55 million pounds less than in 1961. Carbon black shipments during the year totaled 2,082 million pounds and were 5 percent above those of 1961. About one-fifth of these shipments were exported; the balance were sold domestically. An increase of 180 million pounds in domestic sales was partially offset by a decline of 80 million pounds in exports. Total value of carbon black production in 1962 was $145 million. The average value per pound of 7.06 cents was 0.24 cent per pound less than in 1961. Producers' stocks declined 26 million pounds during the year.

Jan 1, 1963

By J. Roger Loebenstein

This report presents a U.S. Bureau of Mines study of the flow of arsenic-containing materials in the United States, based on the best data available in 1991, includes a consideration of arsenic as a byproduct of the processing of nonferrous metals, the fate of arsenic in manufacturing wastes, the quantity of arsenic used in products, tile fate of arsenic in dissipative uses, and the useful life of discarded products. Where possible, estimates are given of the amounts of arsenic lost from the materials flow. Arsenic byproduct of mining nonferrous metals. Historically, most U.S. production has been from the states of Montana, Washington, and Utah. The smelters in these states are believed to be the areas of the country where arsenic is most concentrated in the soil, tailings ponds, and waste dumps. Since the closure of the last domestic producer of arsenic in 1985, all arsenic has been derived from imported sources. Historically, arsenic was important in agricultural applications as an insecticide, herbicide, and cotton desiccant. As the environmental movement gained momentum and the toxicity of arsenic became better understood, most of the agricultural uses for arsenic were banned. Beginning about 1975, the use of arsenic as a wood preservative began to grow. After 1980, wood preservative uses became more important than agricultural applications. By 1990, 70% of the arsenic consumed in the United States was used by the wood preservative industry and 20% by the agricultural industry. The major source of domestic arsenic emissions in 1989 was from the U.S. copper processing indus¬try. About 7,800 mt/yr of arsenic was discarded in leach dumps, tailings, and slag. Another 800 mt/yr was liberated to the atmosphere and 1/100 mt/yr was exported in copper concentrates. On the consumption side, 9,200 mt/yr was lost, mostly from dissipative agricultural uses and the disposal of obsolete arsenical products.

Jan 1, 1994

By Walter R. Storms

This paper , which describes the mining methods and costs at the Atwood copper mine in the Lordsburg ( Virginia ) Mining District of Hidalgo County , N. Mex . , is one of a series being prepared by the Mining Division of the Bureau of Mines on mining practices , methods , and costs in various mining districts of the United States . The mine and surface plant are situated in the west half of sec . 7 , T. 23 S. , R. 18 W. , about 3 miles by road southwest of the center of Lordsburg , near the old abandoned townsite of Valedon ( see fig . 1 ) . The main line of the Southern Pacific Railroad passes through Lordsburg , as does the paved eastwest U. S. Highway 70-80 . A spur line of the Southern Pacific ends near the mine . A good graded road connects the mine with Lordsburg . The following pages present a brief history of the district , describe the geology , and outline methods of prospecting and exploration, including sampling and estimations of tonnages and values . Development, and mining methods are explained , and transportation , ventilation , drainage ,. safety measures , and organization are described . The wage scale and costs of development and mining comprise the corrcluding sections of this circular .

May 1, 1949

By John C. Machisak

INJURY DATA and experience at, coal mines in the United States for 1953 and 1954 are presented in this publication with a minimum of interpretation and comment because of the numerous tables required to afford detailed comparisons between the 2 years. Corresponding tables for 1953 and 1954 follow in consecutive order under the following general sections: (A) General injury experience: Tables 1 to 11: Contain current data on number of fatal and nonfatal injuries, frequency and severity rates, and average severity and time-loss rates. (B) Selected injury data: Tables 12 to 85: Contain current data on causes of injuries, distribution of injuries by part of body injured, days of disability, extent of hand and machine loading, experience by employment and production groups, and various other operating factors and physical conditions related to the occurrence of injuries at the Nation's coal mines.

Jan 1, 1958

By J. P. Hansen

The Bureau of Mines has investigated the S02 leaching of MgO from high-MgO-bearing Florida phosphate concentrates. The S02 was effective in leaching some of the MgO from three phosphate concentrates; flow rate of the S02 and leach time were major factors in determining the amount of MgO leached. Calcining the samples, then grinding to minus 200 mesh, and elevating the leach temperature gave only small increases in the amount of MgO leached. The research also showed that some of the MgO was so intimately associated with the phosphate mineral that it could not be removed by S02 leaching. This amounted to about 0.6, 0.7, and 1.0 pct MgO in three leached residues. The calculated heads for the three concentrate samples averaged 1.4, 1.1, and 1.5 pct MgO, respectively, before leaching.

Jan 1, 1985

By A. Gene Collins

During recent years the interest in trace and minor constituents of oil-field water, petroleum, and their associated reservoir rocks has increased. The metals copper, nickel, lead, manganese, iron, zinc, and cadmium are not determined routinely in oilfield brine analyses. Determination of these metals and subsequent correlation of these data should yield information to aid 1n the interpretation of the origin of different waters. The methods of analyzing oilfield waters have several potential applications: (1) Aiding in the search for petroleum; (2) identifying sources of intrusive brines; (3) controlling corrosion; (4) controlling produced water; increasing knowledge of the geology of subsurface formations; (5) identifying incompatible waters in waterflooding operations; (6) increasing the knowledge of the flow of oil, gas, and water in underground formations; and (7) aiding in the identification and location of valuable mineral reserves. Some brines contain enough valuable minerals to be recovered commercially.

Jan 1, 1962

By Arthur C. McFarlan

There are two distinct coal fields in Kentucky-the Eastern field constituting a part of the Appalachian coal region and the Western field constituting the southern part of the Eastern Interior region. The outcrop pattern of the State is dominated by the Cincinnati arch. Coal-bearing Pennsylvanian strata occupy a low structural position on either flank, preserved thereby from erosion, which in the past has removed these same beds, though a much thinner succession, from the crest of the arch. General geological relationships are shown in figures 1 and 2. On April 13, 1750, Dr. Thomas Walker discovered the first coal recorded in Kentucky. He entered the State through Cumberland Gap (Cave Gap) and found coal a few miles north.

Jan 1, 1944

By A. L. Engel

In previous reports5/ of ore-testing studies, tests made by established methods on typical ores selected as representative of certain mining districts have been described in considerable detail. In addition to established test procedures, such as screen analysis, chemical analysis, microscopical examination of ores and products, sink-and- float separation, gravity concentration, flotation, ,and magnetic separation with or without roasting, it was sometimes necessary to apply other methods, such as leaching, in instances where physical separations were not feasible.

Jan 1, 1940

By George W. Hezzelwood

This paper describing the minim, methods at the mine of the Consolidated Cortez Silver Mines, Cortez, Nevada, is one of a series of similar papers being prepared by the Bureau of Mines on mining practices and costs in the various mining districts of the United States. The Cortez district is situated on the southwest slope of Mt. Tenabo of the Cortez Range, near the middle of the boundary line between Eureka and Lander Counties (fig. 1). The camp of Cortez is 36 miles south of Beowawe, the nearest station on the Southern Pacific and Western Pacific Railroads. Mt. Tenabo, which is the highest summit of the south end of the Cortez mange, has an elevation of 9,240 feet; Cortez is about 6,280 feet above sea level. The Consolidated Cortez Silver Mines is the only company operating in the district at the present time and employs about 60 men. The daily production of l25 tons of silver-lead ore is concentrated in the company's mill of 150 tons capacity. The concentrate is hauled to Beowawe by automobile trucks for shipment to a reduction plant in Salt Lake Valley, Utah.

Jan 1, 1930

By C. M. McCulloch

As part of the Bureau of Mines methane control program, the Pittsburgh coalbed was studied in Washington and Green Counties, Pa., and in Marion and Monongalia Counties, W. Va., where this coalbed is now being mined at its greatest depth. The coalbed thickness appeared to be structurally controlled; the bed was generally thinner near the axes of anticlines and thicker near the axes of synclines. The overburden isopach shows a similar relationship. Most of the clay veins in coal occur in the synclinal troughs, generally under sandstone roof. Cleat orientations measured in 18 underground mines showed that face cleats are perpendicular to the axial trends of the folds, and the butt cleats are parallel to the axial trends, indicating structural control of the cleat. Measurement and analysis of surface joint orientations provide a method for predicting the cleat orientations of the coalbed, but linears measured from infrared photographs and photoindex sheets helped only to determine regional trends. The results of these investigations provide a geologic framework for rational planning for underground mine development to use the best available technology to cope with methane emissions, coalbed discontinuities, and related ground support problems.

Jan 1, 1975

By R. E. Mussler

As part of an overall goal to develop technology that can maintain an adequate supply of minerals to meet national economic and strategic needs, the Bureau of Mines is evaluating a method for selectively extracting nickel and cobalt from low-grade domestic laterites. The method involves electrowinning to recover the metals in pure form; therefore, preliminary laboratory-scale electrowinning tests were conducted in both a nondiaphragm and a diaphragm cell to determine the effect of variables on energy efficiency under controlled conditions. Electrolytes were generally reagent-grade sulfate solutions that were prepared to simulate electrolyte that could be obtained by stripping nickel-and cobalt-rich solvent extraction reagents. Limited tests were conducted with electrolyte generated from laterite leach solutions. Electrical energy consumption in a nondiaphragm cell was 2.06 kwhr/lb Ni with the cell operated at 50° C, a cell feed of 90 g/l Ni, a pH of 3.5, an extraction of 3.2 g/l, and a cathode current density of 20 amp/ft2. The energy requirement decreased with increasing concentration and temperature, and increased with increasing. extraction and current density. At 50° C, energy consumption in the nondiaphragm cell was 21 pct greater than in the diaphragm cell, but it was only 5 pet greater at 65° C. For this reason and because of overall cost considerations, operation at 65° C with the nondiaphragm cell was preferred. Smooth sheets of cobalt were obtained by electrowinning in a nondiaphragm cell at selected temperatures from 50° to 85° C and with cobalt concentrations from 55 to 87 g/l. The energy consumption (1.48 kwhr/lb) was 22 pet lower with a cobalt concentration of 75 g/l and a cell temperature of 65° C than with a cobalt concentration of 55 g/l and a cell temperature of 50° C.

Jan 1, 1981

By W. W. Adams

Increased employment and a lower accident-frequency rate were the outstanding features of the metal- and nonmetal-mining4 industries of the United States in 1939 compared with 1933, according to reports furnished by individual mining companies to the Bureau of Vines, United States Department of the Interior. Except for 1937, the reports for 1939 showed gains both in number of employees and number of mar -hours worked over all years since 1929. The accident-frequency rate per million man-hours of exposure to mining hazards was lower than in any year since 1925. Reports for 1939 revealed a total of 111,909 men employed in and about mines, an increase of inure than 8 percent over 1931 The total volume of labor performed at all mires was slightly more than 299 million plan-hours, an increase of mare than 10 percent over 1938. As these gains suggest, the average employee had a longer period of work in 1939, the increase amounting to r workdays per employee.

Jan 1, 1941

By John R. Reeves

The data presented in this paper form the chief part of a general survey of the oil-shale resources of Indiana. Other papers* have already been published which contain data an various aspects of this resource. In combination, these papers present data with reference to the following points; (1) distribution of the New Albany shale; (2) amount of shale available; (3) homogeneity and thickness of the formation; (4) amount and quality of the oil obtained from the shale; (5) nitrogen content of the shale; (6) extractibility of the shale and its amenity to breaking; (7) some economic factors bearing upon the utilization of the shale; and (3) other miscellaneous factors and data. In the future, technical work on other phases of the general problem is expected to be done with the object of making a complete survey of this resource which is of much potential importance to the state and nation.

Jan 1, 1923

By Guy A. Johnson

The Bureau of Mines, through research and development contracts with the FMC Corp., has developed and tested two automatic fire sensing and suppression systems for large haulage vehicles. This work was undertaken to enhance driver safety, to lessen substantial property damage from fires on large trucks, and to increase the vehicle operator's productivity. One automatic truck fire protection system protects both the engine compartment and brake rid areas, while the second system is used in the engine compartment and fuel tank area. Both systems have redundant fire-sensing capabilities and manual override controls. Upon sensing flames and/or heat, the systems suppress the fire with pressurized, E-C class dry chemical. Both fire protection systems are flexible in design and can be modified for use on other mobile minim' equipment. Prototypes of both systems have been subjected to long-term, in-mine validation testing and actual Eire tests on 100-ton-capacity trucks at the Puma mine near Tucson, Ariz., and the Erie mine at Hoyt Lakes, Minn. During the 4-month endurance test of the first system at Pima, an accidental flash fire occurred in the test truck while it was working in the pit. The system successfully sensed and automatically extinguished the fire with no injury to the driver and little damage to the truck.

Jan 1, 1975

By C. M. McKinney

This report contains Bureau of Mines analyses of 291 samples of crude petroleum from the Gulf Coast Area of Louisiana and Texas. Included are 65 analyses from 51 Louisiana fields and 226 analyses from 216 Texas fields. Analyses from the Texas fields include 90 from 58 Upper Gulf Coast fields, 47 from 28 Middle Gulf Coast fields, and 89 from 40 Lower Gulf Coast fields. The analyses represent fields that produced 1,000 barrels or more per day during at least one of the years 19.57 through 1961, with the exception of 23 analyses from the Texas fields. The fields considered are listed by state and geographical groupings, with field names arranged alphabetically within each grouping. The tabulation also includes information concerning the geological sources of the samples. General characteristics of the crude oils and analytical and computed data determined from the analyses are summarized. Crude oil production data are given for the fields for 1960 and 1961 and are cumulative through 1961.

Jan 1, 1963

By P. Nicholls

[This paper sets forth the burning characteristics of coke used as a domestic fuel as shown by work of the U. S. Bureau of Mines and others. Coke is a truly smokeless solid fuel and is held in high regard for this quality. Ways are being found for making commercial coke from a wider range of cools than heretofore, and tale use of coke for domestic heating is increasing. ACKNOWLEDGMENTS The experimental work reported in this paper was conducted at the Pittsburgh Experiment Station of the U. S. Bureau of Mines cinder the authority of O. P. Hood, chief mechanical engineer; M. L. Orr, assistant feels engineer, and W. M. Brewer, junior fuels engineer, assisted by Charles Schramm cooperated in making the tests.]

Jan 1, 1929

By S. J. Hussey

A jig tailing with gold content ranging from 0.33 to 0.43 oz/ton was leached in weak cyanide solution with extractions of up to 97 pct in 24 hours. By countercurrent batch leaching studies and laboratory pilot plant operation, minus 10- plus 20-mesh and minus 6- plus 16-mesh coconut carbon were loaded to 700 oz/ton of Au. Minor silver in the ore reported in the carbon in amounts of up to 100 oz/ton. Gold adsorption rate data and an equilibrium adsorption curve for minus 10- plus 20-mesh carbon at ambient temperatures were developed and used in the successful application of a cascade design theory. The work was performed as a part of the overall Bureau of Mines research effort to help maintain an adequate domestic supply of metals by making improvements in mineral-processing technology.

Jan 1, 1979

By C. E. Arrington, A. C. Rice

"Part 1. REDUCTION AND USE OF OXIDANTSSUMMARYA study has been made of the volumetric determination of molybdenum by reduction in the Jones reductor, receiving the reduced solution in a mixture of ferric alum and phosphoric acid, and titrating with standard oxidizing agents. In addition to potassium permanganate, which has long been utilized for this titration, potassium dichromate and ceric sulphate have been found to be applicable. The latter oxidants have been found to be especially useful in the form of dilute solutions for the determination of small amounts of molybdenum. The tests revealed that certain internal indicators give excellent results in these titrations.Reason for These ExperimentsThe following study was initiated with the hope of providing the mining and metallurgical industries with an accurate and rapid technical method for the determination of molybdenum in such low-grade materials as ores, rocks, tailings, steels, and alloys containing less than 0.3 percent molybdenum. Although the experimental work was designed with this purpose in mind, many of the results are applicable to material containing a higher percentage of molybdenum.While the Bureau of Mines had an experiment station in Colorado, considerable analytical work was done on what were then (up to about 1923) classed as rare metals. One of these was molybdenum; and in Bulletin 212, Bonardi's (1) 3/ 60-page chapter covered all methods for the analysis of molybdenum."

Apr 1, 1939