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By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Jan 1, 1965

By J. L. Shultz

The investigation of organic compounds in respiratory coal dust by high-resolution mass spectrometry has shown that the organic components differ (1) with particle size, (2) with rank of coal, (3) in coals of same rank from different coal seams, and (4) in respirable mine dust and respirable coal dust (prepared) from the same mine. The eight respirable mine dusts studied are from coal seams in the Appalachian region where the incidence of coal workers' pnumoconiosis is relatively high. The molecular weights of the major organic components vary greatly among these respirable mine dusts; three show strong concentrations of polynuclear aromatic hydrocarbons.

Jan 1, 1972

By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Jan 1, 1965

By A. Viksne

A series of tests were conducted by the Bureau of Mines to determine the best means of reducing noise generated by the detonating cord that is utilized for trunklines in quarry blasting. Ten different types of detonating cord were tested and evaluated for their acoustic qualities. The results of the investigation showed that noise levels produced by "low-core-load-per-foot" detonating cord "not covered" were lower than those produced by "high-core-load-per-foot" detonating cord covered with 6 inches of unconsolidated material.

Jan 1, 1972

By W. C. Wahl, M. M. Fine

Leonardite , a naturally occurring , partially oxidized form of lignite with a high content of humic acids , was investigated as a binder for iron ore pellets . Although insoluble in original condition , leonardite forms watersoluble salts with good binding properties when treated with certain alkalis such as sodium hydroxide . Soluble leonardite imparts excellent dry strength to pellets , but green strength is somewhat lower than that obtainable with bentonite . However , green strength can be improved by adding a small amount of calcium hydroxide to the leonardite - concentrate mixture . Leonardite binders were used successfully on three of the four different concentrates tested .

Jan 1, 1964

By K. A. Fowler, L. W. Higley

Steels with an alloying addition of depleted uranium were studied to develop successful melting , casting , and fabricating methods ; to obtain data on mechanical properties ; and to determine the effects of this alloying element . Uranium in amounts up to 1.5 percent was added to steel - base compositions containing approximately 0.5 percent carbon , 2 percent nickel , 0.25 to 2.0 percent silicon , and 0.75 percent manganese in both vacuum- melted and air -melted heats . Radiation levels were monitored for all operations . Bureau of Mines research at the Rolla Metallurgy Research Center showed that uranium additions did not increase tensile strength ; that hot - shortness occurred during forging above 1,090 ° C because of the presence of a low melting point constituent of a eutectic type ; and although a measurable amount of radioactive contamination resulted from processing , the quantity was never large enough to require the work area to be identified as a radiation area .

Jan 1, 1964

By W. E. Lamont, R. E. Perry, I. L. Feld

The Bureau of Mines conducted research to determine the conditions required to sinter a pyrrhotite calcine into a product suitable for iron blast furnace feed . The calcine , a fine - grained iron oxide produced by roasting sulfide flotation concentrate , analyzed about 60 percent iron and 1 percent sulfur . Sintering of the calcine without prior pelletization was not successful whereas firing of preformed calcine charges yielded acceptable sinter products . Batch tests were made to study the effect of the following variables on the sinter quality : Size of green pellets in the charge , quantity and type of internal carbonaceous fuel used , depth of sinter bed , moisture content of the charge , flux additions , and binder additions . The batch and continuous sinter tests showed that minus 1 / 4 - inch pellets prepared from a mixture of the calcine , coke , dolomite , and water gave sinter cakes analyzing 57 to 61 percent iron and 0.05 to 0.02 percent sulfur .

Dec 1, 1963

By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Dec 1, 1964

By W. F. Netzeband

This paper, which describes mining methods and practices at the Rialto zinc-lead mine American Zinc, Lead & Smelting Co., in northeastern Oklahoma, is one of a series being prepared by the Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States, The Rialto mine is in the SE1/4 SW1/4 sec. 20 and the NW1/4 sec. 29, T. 29 N., R. 23 E., Ottawa County, Okla. (fig. 1). The 200-acre property is southwest of and adjacent to the town of Picher in the central part of the Picher field of the Tri-State zinc-lead mining district (fig. 2). Other mines of the company adjoin the Rialto on the east and south. Zinc-lead ores have been mined almost continuously from the Rialto tract since 1916. The property was acquired by American Zinc, Lead & Smelting Co. late in 1951, and the mine was operated thereafter by the Nellie B Division of that company until the end of 1955, when it was subleased to the Residue Mining Co.

Jan 1, 1958

By Rolf S. Paine

The Bureau of Mines studied the presplitting technique used for control-ling overbreakage in the walls of a vertical shaft at the U.S. Army Corps of Engineers Littleville Dam project near Huntington, Mass. The periphery of the shaft, the dimensions of which were 16-1/2 feet wide by 21 feet long and 52 feet deep, was presplit (cracked) in the solid to a depth of 48 feet prior to full-depth sinking. Presplitting prevented overbreak in a fairly soft schist and provided sound self-supporting walls which required very little scaling.

Jan 1, 1965

By Rolf S. Paine

The Bureau of Mines studied the presplitting technique used for control-ling overbreakage in the walls of a vertical shaft at the U.S. Army Corps of Engineers Littleville Dam project near Huntington, Mass. The periphery of the shaft, the dimensions of which were 16-1/2 feet wide by 21 feet long and 52 feet deep, was presplit (cracked) in the solid to a depth of 48 feet prior to full-depth sinking. Presplitting prevented overbreak in a fairly soft schist and provided sound self-supporting walls which required very little scaling.

Jan 1, 1965

By G. G. Campbell

Bureau of Mines research to develop an in situ retorting recovery method for oil shale has involved field testing of fracturing techniques for creating fluid-flow paths in impermeable oil shale. Electrolinking, hydraulic fracturing without and with sand propping, and explosive fracturing with a liquid explosive were tested in a 25-ft-square, five-spot pattern. These wells were drilled into oil shale at 50-to 88-ft depths near Rock Springs, Wyo. Results of the fracturing tests were evaluated by injecting air into a test well and measuring flow rates and flow profiles in adjacent test wells before and after each test. To identify points of air entry (location of fractures) in wells, flow profiles were determined by use of inflatable packers and by continuous logging with an airflow probe developed during the fracturing program. Electrolinking and hydraulic fracturing without sand propping were relatively ineffective; hydraulic fracturing with sand propping created horizontal fractures with desirable flow capacity; and fracture flow capacity was significantly increased by detonation of nitro-glycerin displaced in the natural and hydraulically induced fracture systems.

Jan 1, 1970

By Jr. Joyce

This report describes sulfatization of nickeliferous laterites from Puerto Rico and the Philippines for recovery of water-soluble nickel and cobalt sulfates. Temperatures ranging from 665 C to 710 C and a 10-percent sulfur dioxide-air reaction gas were employed during batch-roasting tests and during continuous countercurrent treatment in a 2-inch-diameter shaft furnace. A maximum of 69 percent of the nickel and 76 percent of the cobalt were recovered from one sample of Puerto Rican laterite, and a maximum of 96 percent of the nickel and 91 percent of the cobalt were recovered from the Philippine laterite.

Jan 1, 1965

By F. P. Haver

The Bureau of Mines is developing a leach-electrolysis procedure to produce Special High Grade (SHG) zinc from sulfide concentrate without the generation of sulfur oxide gases. Chlorine-oxygen leaching of the concentrate yields zinc chloride (ZnCI2) which, after purification, is electrolyzed in a fused-salt cell to obtain molten zinc metal and chlorine gas for recycle. This paper describes a laboratory-scale investigation made to develop a procedure for electrowinning zinc metal from ZnC12. Zinc chloride by itself is not a suitable electrolyte because it fumes badly above its melting point and is a poor conductor of electricity. Other salts therefore must be added to prevent fuming and improve the conductivity. Optimum results were obtained with a KC1-LiCl-ZnCl2 bath at 500° C, using a current density of 5 amp/in2 and an electrode spacing of 0.5 inch. Under these conditions, SHG zinc was produced at a current efficiency of 94.3 pct and an energy requirement of 1.16 kwhr/lb. Fused-salt electrowinning eliminates the need to handle and melt cathodes and increases the production of metal per unit cell volume through the use of higher current densities than are possible with aqueous electrolysis.

Jan 1, 1976

By E. G. Erspamer

Laboratory investigations were made by the Bureau of Mines on ore containing the sulfides of both mercury and antimony to develop a method or methods for the economic recovery of mercury metal and the concurrent recovery of antimony as metal or salts,. If standard mercury-recovery techniques are applied to such ores, the antimony content interferes with the effective production of mercury metal; further-more, the antimony is lost. This report presents the results of tests on a sample of cinnabar-stibnite ore from the Red Devil mine near Sleitmute, Alaska. Red Devil ore was chosen for the investigation because it is purported to be typical of ores of the Kuskokwim River area, which, in their aggregate, constitute large potential reserves of mercury and antimony. Studies included petrographic, spectrographic, and chemical analyses, gravity-separation tests, bulk flotation of mercury and antimony sulfides, differential flotation, leaching, and furnacing of crude ore and of flotation concentrate.

Jan 1, 1956

By M. J. Lempel

A theoretical study of the heat-transfer characteristics of a dilute gas-solids mixture in an externally heated tube is reported. Detailed equations are developed describing the system, and a numerical method is presented to solve the equations using a digital computer. The methods are applied to a system containing fine coal particles entrained in hydrogen, flowing through a hot tube. Heat-transfer coefficients and several other physical constants are evaluated in detail.

Jan 1, 1967

By C. C. Popoff

The development of glass-making industries in the Pacific Northwest as well as other industries that use pure silica has been retarded by lack of local supplies of low-cost raw material. Several quartz deposits along the Skagit River constitute the only known source of relatively pure silica within the range of cheap transportation to the Seattle industrial area. Although some silica has been mined from these deposits, very little information regarding their size, grade, and other physical characteristics has been available to the general public. As a part of its program of investigation of the mineral resources of the Pacific Northwest, the Bureau of Mines assigned the writer to examine the Skagit River silica deposits in October 1946. This report presents the factual data obtained from an examination of the so-called Stoner, Bacon Creek, and Pressentin deposits. These deposits are the largest and most easily accessible known to exist in the area. The deposits are near Marblemount, which is on State Highway 17A. They are within 1 mile to 1-1/2 miles of the Skagit. River Railway, which provides transportation to Seattle, a distance of 130 miles. None of the deposits has been developed thoroughly. The Stoner deposit, however, has been developed by a quarry about, 5,0 feet square and has been exposed by hydraulic removal of the overburden throughout a distance of 180 feet along the hanging wall of the vein

Jan 1, 1949

By G. M. Potter

During the investigation of the occurrence of manganese deposits in the western United States, examining engineers of the Bureau of Mines collected samples from four properties in Siskiyou and Mendocino Counties northern California. As the ores were too low-grade to be acceptable to manufacturers of ferromanganese, beneficiation studies were made between 1941 and 1945 to determine the amenability of the ores to concentration. The Johnson and Reynolds properties are near Fort Jones Siskiyou County. The ore occurs in a number of small lenses in that area. Samples were taken for testing for amenability to treatment in a small custom-gravity plant, tentatively planned. by the Waiter Johnson interests of San Francisco. A 2-ton representative sample was obtained from numerous exposed portions of an outcrop on the property of the Mayland Mining Co. The Mayland mine is about 8 miles from Sawyers Bar in Siskiyou County. The ore body consists of stringers and irregular masses of oxide, and. silicate ore scattered through quartz, which these minerals have replaced.

Jan 1, 1952

By V. F. Parry, J. B. Goodman, W. S. Landers

"This investigation was conducted: under the direction of A.C. Fieldner, chief, Fuel and Explosives Branch, Bureau of Mines, Washington, D. C. The following members of a Technical .advisory Committee were helpful in advancing the investigation: L. C. Harrington, dean, College of Engineering, University of North Dakota; D. F. Pane, president, Sheridan-Wyoming Coal Co.; Carson W. Smith, president, Consolidated goal & Coke Co.; Durbin van Law, consulting, engineer, Denver & Rio Grande Western Railroad; and C. B. Carpenter, professor of metallurgy, Colorado School of Mines. Coal samples from the Northern Colorado field used in the stoker during 3 years of service were supplied through the cooperation of N. C. Brooks, secretary, Northern Colorado Coals, Inc.This report describes the development and practical tests made on a small stoker-fired system for heating service water automatically. The system was designed to take advantage of the favorable reactivity of low-rank fuels, and the objective was to devise a combination of stoker, heat-receiving, and hot-water storage system Which would be automatic for at least 30 days without attention, while heating service water at minimum cost. The system was developed to a point where coal consumption was less than 10 pounds (or less than 100,000 B.t.u.) per day. The total operating cost of hot water for an average-family-was about $1.00 per month, with coal retailing at $6.00 per ton and electric power at 4 cents a kilowatt-hour. The heating system was designed for the utilization of low-rank fuels, but the general features of the double-tank system can be 'employed fuels, either gas or liquid fuels.The Subbituminous Coal and Lignite Section of the Bureau of Mines began investigations on the utilization of low-rank fuels in domestic appliances during 1939. Tests were made on various devices to find out if they were suitable for the low-rank fuels. Most of the available appliances for burning coal have been designed for the higher-rank fuels, and they are not well-suited for burning the lower-rank coals at maximum efficiency, because subbituminous coals and lignite have high bed moisture ranging between 20 and 40 percent by weight, which lowers heating value to the range of 10,000 to 6,500 B.t.u. per pound. They are noncoking, and the ash content ranges between 4 and 6 percent, with a fusion temperature of about 2,0000 F."

Jun 1, 1946

By N. S. Dalal, A. H. Hoffman, X. Shi, D. E. Banks, J. K. H. Ma, Y. Rojanasakul

Excessive production of reactive oxygen radicals by alveolar macrophages is proposed to play an important role in oxidative lung injury. A major product of oxygen radical formation is the highly reactive hydroxyl radical (•OH) generated via a biologic Fenton reaction. In addition to its known ability to induce lipid peroxidation, recent studies have suggested that the •OH may exert its cytotoxic effect through the alteration of [Ca2+], homeostasis. To test this potential mechanism as well as to investigate the relationship between •OH and Ca" overloading in cytotoxic injury, isolated rat alveolar macrophages were exposed to externally generated radical system, H2O2 (0.01 to 1 mM) and Fe (1 mM) and their [Ca2+] levels and cell injury were monitored using quantitative fluorescence microscopy with the aid of the specific Ca" indicator, Fura-2, and membrane integrity indicator, propidium iodide. Electron spin resonance measurements using the spin trap 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) confirmed the production of the .OH radical by this system. Upon the addition of the radicals, the macrophages displayed a rapid initial rise in [Ca2+] which was followed by a slower but more pronounced [Ca2+], elevation that reached a level 3 to 5 times higher than the basal level. This process preceded cell death as evident by nuclear propidium iodide fluorescence. Depletion of extracellular Ca" inhibited both the [Ca2+], response and cell injury. Preincubation of the cells with the Ca" channel blocker verapamil or .0H radical scavenger mannitol similarly inhibited the [Ca2+], rise and loss of viability. Firefly luciferase assay of cellular ATP content demonstrated that the alterations in [Ca2+], following .0H treatment preceded the depletion of ATP. Changes in membrane potential caused by Na* substitution with K* had no significant effect on either the unstimulated or stimulated [Ca"], levels. Taken together, these measurements indicate that .OH-induced injury in alveolar macrophages is associated with the alteration in [Ca2+], homeostasis. The mechanism of •OH-induced [Ca2+] loading is not due to nonspecific membrane damage or energy depletion, but mainly due to an increase in Ca2+ influx through Ca2+ selective channels. This Ca2+ over-load state as well as energy depletion caused by the oxidant may activate certain cellular degradative processes leading to cell injury and death.

Nov 1, 1995