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By James H. Aase

[This study provides data on the physical and hydrological makeup of the ,t hakes waterway system and forecasts quantities, traffic patterns, and ping cost of prospective bulk mineral commerce projected to be transported it. Factors affecting the shipping cost of iron ore, bituminous coal, imestone were quantified and integrated into a computer program that can d to estimate costs under varying sets of conditions. Combined ship of iron ore, bituminous coal, and limestone in 1995 were estimated at million tons. The cost of operating the U.S. vessel fleet for trans-ng an indicated 80 percent of this traffic tonnage was projected to be $163. 5 million.]

Jan 1, 1970

By C. H. Fisher

Coal carbonization, the basis of a major industry, consists in heating coal in the absence of air at various temperatures (ranging from 500° to 1,000° C.) that are selected according to the kind of products desired. During this treatment, the complex organic substances that comprise the major part of the coal are converted into several useful products that are quite different from the original material. The principal products of coal carbonization or distillation are coke and gas. These products, as well as others of which lower yields are obtained (light oil, tar, and ammonia), occupy an important place in present-day commerce and civilization. This paper is concerned with the composition of the tar and light oil, which, as complex mixtures of organic compounds, are the source of many important dyes, inter-mediates, medicinals, resins, etc. The volatile products obtained when bituminous coals are destructively distilled or carbonized are tar, aqueous liquor, and gas. These products vary in composition and properties, depending on the nature of the coal and the temperature and conditions of carbonization. The tar is a dark, rather thick and viscous liquid at ordinary temperatures, becoming semisolid when cooled to the freezing point of water. The aqueous liquor (chiefly water) contains several inorganic substances and certain organic compounds, which, because of their solubility characteristics, have been extracted from the tar. The carbonization gases consist chiefly of carbon dioxide, carbon monoxide, hydrogen, hydrogen sulphide, ammonia, methane, ethane, ethylene, and several hydrocarbons of higher molecular weight. The hydrocarbons of higher molecular weight (benzene, toluene, xylene, etc.) may be re-moved as liquids from the gas by suitable means. This liquid and the first fractions obtained on distilling the tar are known as light oil.

Jan 1, 1938

By Gerrit V. R. Goodman

Future coal mining systems will be able to cut from crosscut to crosscut where advances could exceed 100 ft. However, limitations arise when ventilating such mining systems. In deep advance mining, there would be no workers at the face to advance ventilation tubing or curtain manually. Traditional methods also provide no means for maintaining face ventilation after the miner backs away from the face. U.S. Bureau of Mines research is studying means to provide effective ventilation at cut depths beyond the current limit of 4D ft. Several innovative ventilation schemes are currently being considered. One such method is the use of a jet fan to ventilate a deep cut. A jet fan is simply a freestanding fan using little or no ducting to direct the ventilation flow. Jet fan testing in a 90-ft entry revealed that higher exit velocities and greater penetration depth occurred when various configurations were used to confine and direct the air flow. Additional testing also indicated that 2,200 cfm of fresh air was delivered to the face? 90 ft distant when a check curtain was used to limit entrainment around the fan. Without this curtain, this quantity dropped to only 1,000 cfm. This testing indicated that a jet fan was capable of providing ventilation to a distant face area. It also highlighted potential problems, such as recirculation at the fan and reentrainment in the jet flow. Despite these potential problems, jet fans may be adequate for ventilating cuts exceeding 4D ft.

Jan 1, 2010

By Glenn C. Reed

This report is one of a series describing investigations within the Missouri River Basin in Montana made by mining engineers of the Bureau of Mines Minerals Division, Region II. The primary purpose of these investigations is to provide information to agencies of the Department of the Interior and and others concerned with the planning of Federal power developments in the basin. The report contains such factual data as have been authorized for public distribution. The field investigations in Broadwater County were made during the late fall of 1948 and the summer of 1949. Virtually all known metallic mineral deposits and some nonmetallic mineral deposits within the county were investigated. However, some long inactive mines and prospects on which little or no information is of record may have been omitted inadvertently. Many of the mines and prospects have been inactive for extended periods. Most of the underground workings now are inaccessible. Because of such conditions, impressions gained by the inspection of surface features have been supplemented necessarily, where possible, by information obtained from Federal and State publications.

Jan 1, 1951

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 J. G. Walters

Analyses of light oils produced from the fluidized carbonization of coal at 485°, 550°, 600°, and 660° C are presented. Tar vapors from 485 C fluidized carbonization were thermally treated at 600°, 700°, and .800° C, and the analyses of light oils produced by this treatment are also presented. Procedures were developed for analysis of coal carbonization light oil by gas chromatography to permit a more definitive analysis than can be obtained by the conventional distillation procedure. An increase in low-boiling olefins, benzene, and toluene, a decrease in low-boiling paraffins, and little change in the remainder of the aromatics was observed with increased temperature of carbonization.

Jan 1, 1965

By C. E. Brechtel

This project describes the design and testing of large face ventilation systems for oil shale mining. A design data base was generated by reviewing general industry practice, oil shale industry planning, and technical literature. Conceptual designs for seven different systems were developed and evaluated for suitability. A large, free-standing, jet fan and reversible fan with rigid duct were selected for fabrication and testing. The two systems were field tested in a dead-end heading 55 ft wide by 30 ft high and 320 ft long. System performance was optimized using measurements of air flow direction and air velocity. Total system performance was then measured using SF6 tracer gas released to simulate blast fumes, hot diesel exhaust, methane layering and methane from a blasted muckpile. Field testing indicated that both systems delivered similar performance. The jet fan offered some clear advantages because of its mobility, ease of oper-ation and lower power requirement. It also offered some functional advantages in ventilating for methane because of it high average velocity.

Jan 1, 1985

By P. Nicholls

Patent records show that the idea that the burning of fuels can be improved by mixing or pretreating them with chemicals 6 dates back to the early years of the last century. By 1845, English and French patents included the specific beneficiations of elimination or reduction of smoke, soot, and clinker; reduction of the ashes, presumably meaning the total weight of refuse from the ashpit; elimination of sulphur fumes; increase in the rate of burning; increase in the time a given charge of fuel would last; and, in most patents, a saving of fuel. The earlier patents specified additions up to 80 pounds or more per ton of fuel, but after 1860 the quantity was rarely more than 4 pounds. There is no record of the extent to which these patents were commercialized, but after 1884 many American patents were assigned to companies specializing in treatment of coal, so it is probable that the products were marketed on a considerable scale at least as early as that date. From 1900 on, many companies marketed proprietary products that were sold under the general name of "fuel savers." Since its establishment in 1910, the Bureau of Mines has continually received inquiries about these products and, at the request of other govern-mental departments, has tested some used in accordance with the instructions of the purveyors; the results were all negative and, within the accuracy of measurements, the products had no effect on the burning.

Jan 1, 1937

By J. K. Whyatt

The U.S. Bureau of Mines has been conducting a series of rock mechanics investigations at the Lucky Friday Mine in the Coeur d'Alene Mining District of northern Idaho. In the present study, the energy release rate (ERR) index was used to evaluate three underhand stope backfill parameters-cement content, density, and placement gap-to determine their influence on rock bursts. This index provides a relative measure of the likelihood of rock bursting for a given rock mass. It is known that the elastic idealization of the rock mass inherent in this method causes underestimation of stope closure and hence underestimation of the influence of backfill on rock bursting. However, this evaluation still showed that (1) changing from present practice to one in which backfill was omitted altogether would increase the ERR by 42 pct and (2) perfect placement of backfill would reduce the ERR below present practice levels by 28 pct. The easiest step toward perfect placement would be elimination of the placement gap, which accounted for half of the difference in ERR between present practice and ideal placement conditions. There was no indication that increasing initial fill strength through increased cement content would affect the ERR.

Jan 1, 2010

By L. A. Readdy

Pilot Hole "X" was drilled to test the formations through which the ventilation shaft for the proposed U.S.B.M. demonstration oil shale mine would be drilled. The geologic formations encountered in this hole are discussed. Correlation of the geologic horizons encountered in this hole with those encountered in nearby drill holes was accomplished by the use of geophysical logs. Data on the geophysical interpretations are provided. The anticipated geotechnical characteristics of the geologic units encountered in Pilot Hole "X" are described.

Jan 1, 1977

By Margaret E. Harris

The formation of nitrogen oxides, the decay of carbon monoxide, and the concentrations of residual hydrocarbons in the secondary combustion zones of propane-air and methane-air flames were studied in three enclosed burners designed to simulate gas appliances such as space and water heaters. The effect of thermally or chemically perturbing the combustion gases above these flames was determined theoretically and by means of factorial experiments. The concentrations of air pollutants and the flame temperatures were measured, and the effects of ingress of secondary air into the primary and secondary combustion zones, flame stability, burner port surface, and simulated recycling of combustion gases were noted. Based on this study, four principles were derived that, applied to gas appliance design, will insure minimal emissions of these air pollutants: 1. Oxides of nitrogen can best be kept low by depressing peak temperatures to about 3,050° F. 2. If this is not possible, then the secondary combustion zone should be cooled rapidly to this temperature. 3. Carbon monoxide concentrations can be limited by rapid induction of secondary air. 4. Hydrocarbon concentrations can be controlled by designing for well-seated, stable flames. In addition, empirical reaction rates were derived that predict the concentrations of nitrogen oxides and carbon monoxide in the primary and secondary combustion zones.

Jan 1, 1970

By Robert C. Merritt

This report describes laboratory as well as pilot heap leaching investigations of low-grade sandstone ores from Wyoming, New Mexico, and Colorado. Sodium carbonate-bicarbonate solutions containing sodium hypochlorite extracted up to 86, 54, and 16 percent U308 from Wyoming, New Mexico, and Colorado ores, respectively. Ammonium carbonate-bicarbonate solutions containing sodium hypochlorite were less effective at leaching these ores. Acid leach in replicate pilot plant testing resulted in U308 extractions of 96, 88, and 81 percent from the Wyoming, New Mexico, and Colorado ores. The development of cost-effective processes for extracting uranium from low-grade ore is essential to the assurance of a continuing domestic supply of uranium.

Jan 1, 1977

By J. E. Chilton

Underground miners may be exposed to hazardous quantities of toxic gases, such as carbon monoxide (CO), generated from mine fires or explosions. Every underground miner is required to carry a filter self-rescuer (FSR), which when operated will remove CO from the miner's breathing air. In addition, every underground miner must have a self-contained self-rescuer (SCSR) near the worksite that will supply breathing oxygen. In many situations, miners do not know when to don either rescuer since they do not know if there is a fire in the mine, nor do they carry instrumentation necessary for the detection of the toxic, colorless, and odorless fire product CO. If each miner carried a personal CO alarm, which would respond to high concentrations of CO, the miner would then be alerted when to don either the FSR or SCSR and exit the mine. A prototype personal miner's CO alarm called PEMCOAL was developed by the U.S. Bureau of Mines. The PEMCOAL unit is small enough to be carried on a miner's belt, has a flash lamp visual alarm, requires no calibration for use, and uses a chemical sensor that changes color by reaction with trace quantities of CO. The chemical sensor was tested at concentrations of CO from 10 to 1,000 ppm, at temperatures from 5° to 40° C, and with several potential mine gas interferents. The PEMCOAL alarm times were sufficiently fast to warn miners before they are exposed to hazardous quantities of CO.

Jan 1, 1989

The first metal-mine accident-prevention course was prepared and published 1942-45 as a series of seven miners' circulars (Nos. 51-57). The course has been broadened, revised, and brought up to date and is being published as a similar series of seven miners' circulars on accident prevention at metal and nonmetallic mines. These circulars are: 1. Accident Statistics (Miners' Circular 51), dealing with general statistics on accidents and injuries at metal and nonmetallic mines, including causes, costs, and the uses of investigations and reports of all accidents.

Jan 1, 1957

By Roy F. Abernethy

This publication by the Federal Bureau of Mines contains the free-swelling indexes for 2,812 samples of coal received from January 26, 1948, to July 15, 1957, and the Hardgrove grindability indexes for 2,339 samples of coal received from June 23, 1947, to July 15, 1957. These data consist of the origin of the sample, bed name, and analysis. Summaries show the high, low, and average values for each bed. The free-swelling index is a relative measure of the caking properties of a coal when burned on a grate, and the Hardgrove grindability index is used to estimate the relative ease of grinding coals. Development and standardization of these test procedures were at a much later date than those for the more familiar tests, such as proximate and ultimate analyses and calorific value determinations. The newer tests are valuable in supplying supplemental information, particularly for assisting in evaluating coals used in certain types of combustion processes.4/ Data from such tests are important to designers of burning equipment, operating engineers, and purchasing agents. Data from these newer tests are scarce and scattered through a number of publications. Special projects were started to determine the free-swelling and grindability indexes, in addition to the regular analyses on the tipple samples collected by Bureau engineers. Since the start of these special projects, all the coal fields of commercial importance have been adequately covered in the sampling program.

Jan 1, 1961

By David J. Kusler

The Bureau of Mines reviewed current technology in the refractories consuming industries and evaluated the impact of changes in technology on the supply and demand of refractories. Literature was searched and contacts were made with leading consumers and producers of refractories. The distribution of refractories by value of shipments to users was surveyed. The report shows that the percentage distribution of refractories sales to the consuming industries has remained essentially constant during the last decade but that substantial changes have occurred in the relative distribution of types of refractories. The trend in pyroprocessing technology in recent years has been toward higher temperatures, which require more costly refractories. This fact is reflected in the impressive gain in the dollar value of refractories sales, which in 1968 was about one-third greater than in 1960, and the rapid growth of refractories based on high-alumina, magnesia, zirconia, carbon, and other materials, at the expense of fire clay, silica, and chrome- based refractories. An appendix to the report contains refractories value and shipment data tabulated in a manner by which trends in the distribution of refractory types can be observed from 1955 to 1968. In addition, unit values are presented on a per-ton basis for comparison.

Jan 1, 1970

By Daryl R. Tweeton

This Bureau of Mines publication provides information to assist in selecting a lixiviant (leach solution) for in situ uranium leaching. The cost, advantages, and disadvantages of lixiviants currently used and proposed are presented. Laboratory and field tests are described, and applications of geochemical models are discussed. Environmental, economic, and technical factors should all be considered. Satisfying environmental regulations on restoring groundwater quality is becoming an overriding factor, favoring sodium bicarbonate or dissolved carbon dioxide over ammonium carbonate. The cheapest lixiviant is dissolved carbon dioxide, but it is not effective in all deposits. Technical factors include clay swelling by sodium, acid consumption by calcite, and the low solubility of oxygen in shallow deposits. Laboratory leaching tests can provide useful data. However, they can be misleading if, for example, the ore is allowed to oxidize before testing or if distilled water instead of formation water is used for making solutions for permeability tests. Geochemical models presently are more useful for indicating trends in solubility than in reliably predicting concentrations.

Jan 1, 1981

By B. E. Blair

"This report presents the physical properties and related geological and petrographic data of some 84 rock types from operating mines, quarries, or blasting research test sites. These fundamental rock data were collected as a quantitative approach to underground mining problems, blasting research, or other related studies; however, the data are equally applicable to any problem wherein rock characteristics are important factors. Stress-strain curves are given where available, and the standardized procedure for determining elastic constants from static tension tests is described. Computed (laboratory) and measured (field) free-medium velocities are compared in those instances where such data are available. A chart is given showing both the optimum and minimum number of test specimens for the various core sizes employed in the Bureau of Mines standardized physical-property tests. Rock-type, geographical, and geological indexes are included to aid the reader in locating physical-property data in this and previously published Bureau of Mines physical-property reports.INTROD'OCTI ONThis report presents the physical properties of 84 rock types tested from 16 different projects (sections 37-52). Two previous physical-property reports 2-3 / (hereinafter referred to as parts I and II) presented data on 160 rock types from 36 different projects (part I, sections 1-25 and part II, sections 26-36).The physical-property data were originally obtained to supplement structural mining problems, seismic studies, or related investigations; however, they should be equally applicable in all fields of studies where the strength, hardness, or other properties of rock are important factors. The properties, determined from laboratory tests performed on diamond-drill core, include the following:"

Jun 1, 1955

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 K. K. Kelley

The entropy values at 298.1° K. for the elements and inorganic compounds, on which sufficient data were available for calculation in 1931, were discussed in a previous publication (96).3 Since that time the specific beats at low' temperatures of many more inorganic substances have been determined, and considerable advances have been made in the realms of spectroscopy applicable to the determination of thermodynamic properties. Moreover, a critical study of the existing vapor-pressure data made by the author (98) furnishes entropy of vaporization results suitable for obtaining approximate values of the entropies of a number of gases from the entropies of the solids or liquids. Consequently, it appears worth while at the present time to supplement the former publication, giving the new values now obtainable and making such revision in the older values as the data warrant. The methods of calculating entropies were discussed in previous publications (96, 98) and will not be repeated here. ENTROPIES AT 298.1° K. FOR INORGANIC SUBSTANCES In the following pages, the same arrangement is followed as in the previous publication (96). All entropy values are expressed in 15° gram-calories per degree Kelvin per gram-formula mass of substance. The figures given for gases do not include the effect of nuclear spin, as is nearly universally customary at present. The estimates of accuracy in the case of the values obtained from heat-capacity data apply only to the existing measurements and to the necessary extrapolations as they are made. It is assumed usually that the substances are in such an energy condition at the lowest temperatures reached in the specific-heat measurements that the usual normal type of extrapolation may be made. No allowance is made for error in this assumption. The recent work on Gd2SO4. 8H2O and FeC13 illustrates the difficulties that may arise in obtaining the entropies of some paramagnetic substances. Also the data and calculations for such substances as CO, H20, and N20 show that the correct entropy is not obtained in all cases by indiscriminate application of the usual

Jan 1, 1936