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By J. E. Hamak

This publication contains analyses and related source data for 144 natural gas samples from 19 States. Of the total samples, 139 were collected during calendar year 1990. The remainder were collected earlier, but releases granting permission to publish were not received until 1990. All samples were obtained and analyzed as part of the U.S. Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free-market economies. This survey has been conducted since 1917. The analyses were made by mass spectrometer and chromatograph.

Jan 1, 1991

By Causey J. Douglas

In 1988, at the request of the Bureau of land Management, the U.S. Bureau of Mines studied part of the 13,460-acre Owyhee Breaks Wilderness Study Area (OR-003-059) in order to evaluate its identified mineral resources. The study area is in Malheur County, OR, about 27 miles northwest of Jordan Valley. No mineral resources were identified in the study area during this investigation. There is an occurrence of jasper along Birch Creek and an associated occurrence of zeolite in some tuffs. In the northern part of the study area is an occurrence of bentonitic clay containing less than 40,000 tons. Much of the area is covered by landslide blocks, colluvium, earthflow deposits, and talus, composed of Tertiary-age volcanic rocks. The upper plateaus are capped by Tertiary-age basalt.

Jan 1, 1989

By T. A. Klinefelter

"INTRODUCTION During the development work on sponge iron by the Bureau of lines it was desired to produce a product of maximum density for the furnace. One means of doing this would be to make a plastic mixture of the ground ore and extrude as pellets or large slugs or brick shapes.If a pelletizing Process is employed, the pellets must be strong enough to resist breaking when rolled and tumbled in going through the rotary kiln. If a brick-making process is employed, the brick must be strong enough to withstand handling and considerable pressure when stacked in the kilns.The study had two objectives: first, to find a binder of sufficient strength throughout the early stages of curing and heat treating and, second, to determine the degree of curing and heat treatment necessary to prevent disintegration under normal working conditions.Although the investigation had as its primary objective the processing of sponge iron, the data should interest other industries in which non plastic or poor-bonding slimes are a problem."

Jan 1, 1946

By C. R. Stephan, N. B. Greninger, J. R. Lipscomb

The U.S. Bureau of Mines and the U.S. Mine Safety and Health Administration (MSHA) are participating jointly in a research program to evaluate the strength characteristics and air-leakage resistance of various proposed seal designs for use in underground coal mines. The full-scale seals were constructed in the USBM's experimental mine at the Lake Lynn Laboratory, air-leakage tested, then subjected to pressure pulses of 20 psig or greater. bjected to pressure pulses of 20 psig or greater. In experiments prior to this study, seven seal designs using solid-concrete blocks were tested. Only the standard-type seal passed the explosion and air-leakage criteria. Tests also were performed on four seals constructed with low-density foam blocks. All four of these seal designs withstood the pressure pulse. In more recent studies, nine cementitious foam seal designs of varying thicknesses and densities were investigated. Six of the nine designs successfully survived the explosion overpressures. Six wood- block convergence seals also have been tested. The typical 3-ft-thick, wood-block seal design currently used in many coal mines did not maintain its integrity, in the absence of convergence forces, following the explosion test. Five modified wood-block seals successfully withstood the 20-psig pressure pulse. Based on these tests, three alternative seal construction materials, cementitious foam, low-density foam block, and wood, have been approved by MSHA for use in underground coal mines.

Jan 1, 1993

By Joseph Grumer

The range of composition of gases synthesized from solid fuels which are exchangeable with natural gas on current gas appliances was evaluated by theoretical principles. These principles consider primarily the flashback, blowoff, and yellow-tipping characteristics of air-entraining burner flames. It was found that complete identity between the synthetic and natural product is not necessary. Gases such as may be obtained by hydrogasification of coal and other solid fuels without the removal of unreacted hydrogen offer advantages in flame characteristics. Between 25 to 37 percent hydrogen can be tolerated in the sendout gas.

Jan 1, 1965

By S. J. Pearce

The need for a simple, very sensitive, and accurate method for the determination of benzene in blood and urine vas evident throughout a recent study of chronic benzene (C6H6) poisoning conducted cooperatively by the United States Bureau of Mines, The Barrett Company, and the producers of benzene. A combustion method which will be described in a later publication, and a previously described/ adaptation of Smyth's method were developed and used during that investigation. The adaptation of Smyth's method gave satisfactory results when dealing with exposure conditions that produced chronic poisoning in a comparatively few days, but it was time-consuming; and lacked the accuracy necessary for a study of the absorption, distribution, and fate of benzene in the body during exposure to threshold concentrations of benzene vapor in air. The combustion procedure was satisfactory from the standpoint of sensitivity but was cumbersome, intricate, time-consuming, and required the use of special and somewhat expensive Physical and chemical apparatus. Following the termination of this study of chronic poisoning, possibilities ides for developing better methods occurred, and these have been investigated by the Bureau of Mines with the aid of Relief Works Division personnel microcolorimetric method for the determination of benzene in air has been described recently.6/ The present report deals rich the adaptation of this new colorimetric method to the determination

Jan 1, 1936

By J. W. Chester

The rapid depletion of zinc-lead ore reserves and the rising costs of exploration have been major factors in the decline of mining activities and explorations for additional reserves in the Tri-State mining district. There is a need to develop new or adopt known, improved exploration techniques that will appreciably lower the costs of exploration. Demonstration of the practicability of using improved techniques to indicate, rapidly and cheaply, mineralized areas or geologic structures where more intensive explorations are justified could stimulate the search for and discovery of additional ore reserves. Various operators in the Tri-State district have used geophysical surveys to some extent since 1928 to guide exploratory drilling. Some geophysical investigations have also been made in the district by the State Geological Surveys of Kansas (11)3/ and Missouri (8, 13) and by Federal agencies (16), with the objective of directing exploratory drilling to areas where geologic conditions favored ore deposition. Many factual data obtained have not been published. The investigations generally have not been broad enough to permit conclusive evaluation of the usefulness of the geophysical techniques in all parts of the district.

Jan 1, 1959

By J. J. Forbes

The investigation of major and minor coal-mine disasters has been a routine function of the Bureau of Mines since its inception in 1910, and the facts obtained during such investigations have been used as a basis for determining the precautions that the personnel of many mines are observing to prevent similar occurrences, The Bureau has conducted extensive research on roof-control problems, but a comprehensive study of fatal roof-fall accidents was not attempted until February 10, 1950, when the policy of investigating all coal-mine fatalities was approved by Bureau of Mines Director James Boyd. The investigations are being conducted by Federal coal-mine inspectors functioning under the provisions of the Coal Mine Inspection and Investigation Act of May 1941, Public Law 49, and reports covering the investigations are distributed to management, the State mine inspection agency, and representatives of the mine workers organization having jurisdiction at the mine. SCOPE AND PURPOSE OF STUDY This study covers the Federal investigation of 263 of the 315 fatalities from falls of roof, face, or rib that were charged to the bituminous-coal industry during the calender year 1950. The number of roof-fall fatalities investigated is recorded by States in table 1.

Jan 1, 1951

By L. L. Oden

The Bureau of Mines has studied a number of processes to remove Cu from molten steel scrap with the objective of determining if any of the laboratory methods studied warranted in depth research investigations. Experimental approaches included oxidizing Cu from steel containing other metals that form stable mixed oxides with Cu (AI, Cr, Fe, Mn, Mo, and V), injecting the same metals as oxides to simplify the mechanism of complex oxide formation, partitioning Cu into alkali or alkaline earth silicate slags or oxide-moderated sulfides, and coremoving Cu and S by injecting active compounds of Ca and Mg. The most promising tests, producing nearly 0.3 pct Cu in the slag, used Ar injection of K20-moderated Na2S-FeS below the surface of molten steel containing about 0.6 pct Cu and protected by a CaO-SiOz slag; however, in depth research investigations currently are not felt to be warranted.

Jan 1, 1987

By Charles B. Kenahan

Application of ultrasonics in the electrolytic deposition of metallic manganese and manganese dioxide from sulfate electrolytes had several effects. Ultrasonics produced finer-grained deposits of electrolytic manganese at all current densities than obtained in normal cell operation, but at high current densities it resulted in less adherent deposits. Ultrasonic radiation did not affect cell voltage or cathode current efficiency. In the electrodeposition of manganese dioxide at 70° C., ultrasonic-; increased the current efficiency and decreased the cell voltage at a current density of 9 amperes per square foot, but it had little effect at current densities above this. The decrease in cell voltage was caused by the depolarizing action of ultrasonics at both anode and cathode. Ultrasonic radiation produced a smooth, glossy, adherent, and pit-free deposit at all current densities and at each temperature. Radiation had no effect on current efficiency or cell voltage at 90° C. Ultrasonics was more effective than conventional agitation in producing all of these effects.

Jan 1, 1962

By M. R. Yenchek

The U.S. Bureau of Mines has determined a method for calculating coal mine portable power cable thermal life for a specified temperature loading. This work was the culmination of a multifaceted research project involving (1) accelerated life tests of insulation and jacket materials and (2) steady-state and cyclical loading of cables. Composite Arrhenius curves were derived for common insulation and jacket materials to identify the key cable quality that precipitates thermal failure. Plots of temperature rise versus current for popular cable sizes were then referenced to develop a correspondence between cable life, based upon thermal degradation and current loading. Predictions of cable thermal life were made through integration over variable load cycles and, consequently variable operating temperatures. This procedure may have utility for both the U.S. Mine Safety and Health Administration and mining machine designers in determining the appropriate cable size for new equipment.

Jan 1, 1991

By A. J. Kraemer

The Bureau of Mines for a number of years has been carrying on an investigation of properties of crude oils from producing fields in the United States and has published a series of reports on different fields, including oil fields of Texas3. Production Data The Spindletop field was discovered in 1901 when the pay sand was found at deaths of about 800 feet. During the following twenty-five years a number of attempts were made to find a deep productive sand. All attempts sere failures until a roll drilled by the Yount Lee Oil Company found oil late in 1925. An intensive drilling campaign began at once, and the production of the Spindletop field increased to a daily average of 93,217 barrels in September, 1926; the present production is estimated at 66,000 barrels doily. Tile following table taken from the Oil and Gas Journal for February 10, 1927, shows the daily average and the total production by ninths for 1926.

Jan 1, 1927

By H. Polat, Q. Hu, S. Chander

"The collection efficiency of dust particles was determined in a laboratory dust chamber equipped with a water spray. Measurements were made in the presence of selected nonionic, cationic and anionic surfactants. For the nonionic and the anionic reagents, efficiency was maximum in a narrow range of concentration. The surfactant concentration corresponding to high collection efficiency was usually much below the commonly used concentration of l "", however. In comparison, much higher collection efficiency was observed for a cationic surfactant at extremely low concentrations. For delineating the mechanism of capture of dust particles, surface tension and contact angle results were used to obtain a correlation between the work of adhesion and the efficiency of collection. Such a correlation was reasonable for the nonionic surfactants but not for charged surfactants. In the latter case, electrostatic interactions between charged droplets and particles were more important, especially for the cationic reagent. INTRODUCTIONSeveral methods are used to control dust in mines. These include: ventilation, foam, scrubbers and sprays. This article is concerned with improving the effectiveness of water sprays, which are widely used to remove dust particles during continuous mining, by adding small quantities of surfactants. Water sprays produce small droplets which act as collectors of dust particles suspended in air. Sprays directed at the actual source of dust have the additional property of wetting the coal before the ·particles become airborne (Hamilton, 1974). Wetting agents, also called surfactants, arc known to play an important role in many applications where dust is a problem. However, conflicting reports exist in the literature with regard to the effectiveness of surfactants in water sprays (for a review, see Chander et al., 1988). In spite of the conflicting reports, the use of surfactants for dust control has increased over the years. In a recent study by the Bureau of Mines, a 27'6 reduction in respirable dust levels was observed in a mine test when surfactants were added to sprays (Foley, 1991)."

Mar 1, 1992

By Paul R. Amyotte, Omotayo Kalejaiye, Kenneth L. Cashdollar, Michael J. Pegg

The Siwek 20-L chamber is widely used throughout the world to evaluate the explosibility of dusts. This research evaluated the quality of dust dispersion in the Siwek 20-L chamber using Pittsburgh coal, Gilsonite, and purple K dusts. A Pittsburgh Research Laboratory (PRL) optical dust probe was used to measure optical transmittance through the dust cloud at various locations within the chamber. A total of 540 tests were performed, with triplicate tests at five nominal dust concentrations and six locations. The two standard dispersion nozzles (rebound and perforated annular nozzle) were compared. The transmissions corresponding to the normal ignition delay period were used to: (a) determine variations in spatial uniformity of dispersion obtained with both nozzles; (b) make comparisons between the experimental transmission data and those calculated from theory for the three dusts; and (c) make comparisons with transmission data measured in the PRI, 20-L and Fike 1 -m3 dust explosion chambers. The uniformity of dispersion for the three dusts was similar with both nozzles, despite the differences in nozzle geometry and mode of operation. Transmission data of the three dusts were all significantly lower than those calculated from theory. This was discovered to be, in part, due to significant reduction in particle size that occurred during dispersion. By measuring particle sizes before and after dispersion, values of 60%, 50%, and 20% reduction in particle size (based on the surface weighted mean diameter) were obtained for Pittsburgh coal, Gilsonite, and purple K, respectively. Transmission data from the PRL 20-L, Fike 1 -m3 and the Siwek 20-L chambers indicated comparable results in terms of uniformity of dispersion. However, transmission data from the Siwek 20-L chamber were significantly lower than those of the PRL and Fike chambers. Again, this was attributed, in part, to the significant reduction in particle size that occurred during dispersion in the Siwek chamber. The design of the outlet (dispersion) valve of the Siwek 20-L apparatus charge vessel was largely responsible for the particle break-up. The contribution to particle break-up by the dispersion nozzles and the high level of turbulence in the chamber were found to be minimal. This is a significant finding in that the dust particle size tested for explosibility in the Siwek chamber is considerably smaller than the original dust sample.

By G. R. Palmer

Using a fluidized, countercurrent multiple-compartment ion-exchange (MCIX) column previously developed by the Bureau of Mines, Bureau researchers have successfully extracted uranium from a simulated acidic in situ leach liquor that contained 150 ppm U30s? This successful demonstration of the MCIX system is reported, and the effects of varying the operating conditions on the performance of the system are also examined. Operating the MCIX system with a flow rate of 15 gpm/ft2 and an aqueous-to-resin flow ratio of 200:1, more than 90 percent of the uranium Has extracted, and a resin containing approximately 28 grams U308 per liter was produced. The absorption column used to investigate the operating variables was approximately 18 feet long with a 2-inch ID and was divided into compartments that were 1 foot long.

Jan 1, 1980

By Sidney Katell

This Bureau of Mines study estimates typical capital investments, operating costs, and selling prices for two bituminous coal strip mines in the Eastern and Interior provinces and a subbituminous coal operation in the Northern Great Plains province. The annual productions were based on tonnage required to fuel a 250-million-standard-cubic-foot-per-day, high-Btu gas plant. The annual tonnage for the Eastern province mine is 4.8 million tons; for the Interior province mine, 6.72 million tons; and for the Northern Great Plains province mine, 9.2 million tons. It is assumed that the mines have a 20-year life. Wages and union welfare payments are considered as of December 6, 1974, under the terms of the Bituminous Wage Agreement of 1974, and costs for material and equipment are based on 1975 indexes. Initial capital investment varies: $65,137,900 for the 4.8-million-ton-per-year (MM tpy) mine in the Eastern province, $78,514,600 for the 6.72-MM-tpy mine in the Interior province, and $42,050,100 for the 9.2-MM-tpy mine in the Northern Great Plains province. Total capital investments for the Eastern province mine, the Interior province mine, and the Northern Great Plains province mine are $86,969,900, $109,378,500, and $78,543,500, respectively. Corresponding selling prices for the coal, per ton, are $6.94, $6.03, and $3.39, assuming a 15-percent discounted cash flow rate of return after Federal income taxes. These studies are considered typical for the areas involved. Costs will vary depending on specific locations in these areas.

Jan 1, 1976

From time to time the Bureau of Mines has interpreted and applied certain provisions of the Federal Coal Mine Safety Act and Federal Mine Safety Codes, primarily for the guidance of Federal Coal Mine Inspectors. Although interpretations of the Act have appeared in the Federal Register, the Code interpretations and practical applications have not been published. In response to many requests from representatives of the coal-mining industry, the Bureau is publishing this information to promote better understanding of those provisions that may be misinterpreted or misapplied. INTERPRETATIONS AND APPLICATIONS Two Federal Mine Safety Codes are discussed in this report, namely the Federal Mine Safety Code for Bituminous-Coal and Lignite Mines of the United States, Part 1, and the Federal Mine Safety Code, Anthracite Mines of the United States, Part 1. In this circular the word Codes refers to both directives; Code* refers to the code for bituminous-coal and lignite mines; Code? refers to the one for anthracite mines. Act* refers only to bituminous-coal and lignite mines.

Jan 1, 1963

By A. W. Fahrenwald

The logic leading to the development of the experiments in this paper already has been stated in Part I,3 but is briefly as follows: The results of the batch-grind experiments in which time of "grind" and fineness of finished product were the variables, strongly indicated (1) that batch grinding involving a single grind could not be operated under any condition to give maximum mill efficiency, (2) that the, sieve analysis of the feed charge in the mill materially affected the efficiency of the mill, and (3) that the percentage of finished product in the mill is a vital factor in ball-mill efficiency. A laboratory closed-circuit grind technic designed to simulate present closed-circuit grinding suggested itself, in which: a ball mill and a classifier constitute the grinding unit. The features of the closed-circuit grinding system are: (1) Short large diameter mills, (3) rapid flow of pulp through the mill, (3) continuous automatic removal of finished product from the system, and (4) high circulating loads. The high circulating load is a result if the short length of the Mill - that is, of the time the charge remains in the mill - and the small percentage of finished material produced during each circuit of the feed through the mill.

Jan 1, 1930

By John P. Harmon

A group of organic chemicals, known as wetting agents, has been developed, primarily for use in the textile industry. These chemicals have the property of reducing the surface tension of water when mixed with it in very dilute solutions. The advantage of lowered surface tension is recognized in dust-control work, and several wetting agents, have been tried by dust-control engineers with varying degrees of success. It is well-known that certain solids, coal for instance, are extremely hard to wet with plain water because of the high surface tension of water and the water-repellent action of coal. If the surface tension of the water is reduced, it can be demonstrated that the coal can be wetted easily. This is accomplished practical and at law cost by dissolving a very small percentage of wetting agent in the water that is to be used for wetting purposes. (Care should be exercised in using a wetting agent to be sure that it will not interfere with a subsequent process.) For some time, the comparative efficiency of various wetting agents has been the subject of considerable work by dust-control men at coal mines, as well as by members of the Bureau of Mines 3/, 4/, 5/, 6/. In this connection, a number of samples of air-borne dust have been collected in the mines. With the exception of dust-control measures conditions of dust generation and dissemination were maintained as, nearly uniform as possible. Samples were collected when water alone was sprayed on the cutter bar of a mining machine; various wetting agents were then successively added to the water and more samples of air-borne dust were-collected.

Jan 1, 1946

In 2006, a total of 741 nonmetal mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 These mines (e.g., potash, gypsum, salt) comprised 5.0% of all operations. ? Mines producing common clay comprised 25.2% (n=187) of all nonmetal mining operations. ? Nonmetal mining operations were located in all states and territories except Alaska, Delaware, Hawaii, Maine, New Hampshire, Rhode Island, Puerto Rico, and the Virgin Islands.

Jan 1, 2008