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By C. M. Frost

Crude shale oil produced during in situ retorting by the Bureau of Mines at Rock Springs, Wyo., was refined by three schemes. In the first, the crude oil was fractionated to raw naphtha and 400° F+ residuum. The residuum was hydrogenated over cobalt molybdate catalyst at 815° F and 1,100 psig. The blended raw and 160°-400° F hydrogenated naphthas were hydrodenitrified and then catalytically reformed. The 400° F+ hydrogenated oil was catalytically cracked. In the second scheme, the crude was hydrogenated over nickel-tungsten catalyst at 800° F and 1,500 psig. The hydrogenated fractions were processed by methods used in the first scheme. The third scheme resembled the second but, prior to hydrogenation, the crude was "hydrostabilized" over cobalt molybdate at 500° F and 500 psig. Yields of reformate and cat-cracked gasoline as volume-percents of the crude, and research-method octane numbers (with 3 ml TEL) for the three methods were as follows: First method, 32 pet reformate, 90 octane; 19.5 pct cracked gasoline, 99.2 octane. Second method, 29 pet reformate, 81.1 octane; 21.3 pct cracked gasoline, 99.6 octane. Third method, 28.2 pet reformate, 86 octane; 28.7 pct cracked gasoline, 95.9 octane.

Jan 1, 1974

By Jr. Karr

The Bureau of Mines studied the influence of carbonization method, temperature, and carrier gas on the composition of eight different low-temperature tars produced from a Colorado subbituminous coal. A fluidized bed was compared with an entrained bed, temperature was varied from 500° C to 650° C, and external heating using recycle gas as the carrier gas was compared with internal heating using oxygen-containing gas. The entrained bed yielded significantly more m-cresol and m-ethylphenol, indicating that thermodynamic equilibrium was more nearly approached in the system. Increasing the temperature greatly increased the yield of benzenes and naphthalenes, while paraffins, olefins, and total tar acids were reduced. Using oxygen in the carrier gas decreased the yield of low-boiling phenols and increased that of paraffins and olefins at 650° C.

Jan 1, 1966

By Henry E. Blake

Defluorination studies on refractory fluoride - bearing compounds and minerals , particularly on partly defluorinated residues from high - temperature pyrohydrolysis , required a dependable and reasonably accurate analyticalcontrol method for the analysis of fluorine . The difficulty in liberating fluorine from the fluorides of metallic elements such as aluminum, zirconium , and rare earths by steam- distillation can be largely overcome if the distillation is made from a sulfuric - phosphoric acid solution of a sodium carbonate fusion of the sample material and if the distillation temperature is maintained at about 155 ° C. The data presented in this paper show that liberation of fluorine by this method is more complete and proceeds more rapidly than by usual distillations from perchloric or sulfuric acid alone or a mixture of phosphoric and perchloric acids . Fluorine in amounts ranging up to about 140 mg can be recovered by collecting only about 300 ml of distillate . Determination of fluoride in the distillate is made by the usual thorium nitrate titration .

Jan 1, 1963

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 C. A. Pearson, W. D. Dietzman, M. E. Hawkins

Results of chemical analyses and electrical resistivity measurements of 422 samples of oilfield brines from 120 east Texas fields in Railroad Commission of Texas Districts 5 and 6 are presented in tabular form . These samples represent water from all of the major petroleum- productive formations in the area . Water analyses and electrical resistivity data , when fully utilized by proper study techniques , are useful tools in the solution of many engineering problems such as detection of well leaks , identification of water sources , and interpretation of electrical well logs . In the area included in this study , these representative data should facilitate the solution of problems in which water analysis and water resistivity are factors .

Jan 1, 1964

By A. L. Johns, M. V. Healey

This paper presents one of a series of digests of foreign mining legis- lation and court decisions which is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of tie laws of Ecuador has been prepared from the best available information in Washington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consular officers to whom it is being referred through the courtesy of the Department of State..

May 1, 1930

By R. V. Ramani, C. B. Manula, A. Owili-Eger

PART 1 THE INPUT AND OUTPUT DATA AND THE MINE SCHEMATIC SHOWING THE FLOWS FROM COMPUTER SOLUTIONS FOR APPLICATION I

Jan 1, 1975

By G. W. Birge, D. E. Wolfson, J. H. Lynch

This report by the Federal Bureau of Mines describes the carbonizing properties of coals from the principal beds in Boone County , W. Va . Results are given for samples of coals from No. 5 Block , Stockton - Lewiston , Coalburg , Winifrede , Chilton , Hernshaw , Cedar Grove , Alma , and No. 2 Gas beds . Boone County coals rank as high -volatile A bituminous . Eighteen of the 21 samples tested contained from 3.3 to 7.9 percent ash and 16 of the samples contained from 0.6 to 0.9 percent sulfur . Two samples from the Alma and No. 2 Gas beds , the lowest stratigraphically of the seams tested in Boone County , contained from 1.4 to 2.7 percent sulfur . Most Boone County coals yield

Jul 1, 1960

By M. L. Davis

The principal causes of many methane-gas explosions that have occurred in anthracite mines, especially in thick pitching veins, during recent years can be traced to lack of a satisfactory method of testing for such gas in areas adjacent to those in which blasting is to be done or other sources of ignition introduced. As coal-mine officials and inspectors are required to make examinations for methane in all accessible open workings, including high places, and permissible flame safety lamps have been used almost universally for making these examinations, considerable difficulty has been experienced in proper testing of atmospheres at elevations beyond the normal reach of the examiner, and resultant explosions have often indicated perfunctory tests. The accepted practice of testing for gas in voids or high places generally consists of raising a flame safety lamp, suspended from the end of a long drill, stick, or pipe, into the atmosphere to be tested. Disadvantages noted are: Action of the flame within the lamp cannot be seen readily when the lamp is more then 18 inches overhead, the flame will not be extinguished when less than about 4-1/2 percent of methane is present, and indications of small percentages of methane within the lamp may disappear entirely while the lamp is being lowered slowly to view; the examiner must usually be exposed unnecessarily to falling material; and the lamp may fall and be broken. Thus, the need for a more reliable, safe method of testing for gas in out-of-reach places is apparent. Several electrical methane detectors, tested and approved by the Bureau of Mines, have been used satisfactorily, though infrequently, for making the aforementioned gas tests. Some of these detectors employ a rubber aspirator bulb and rubber tubing of suitable length to draw the atmosphere from high places through and over energized parts of the detector. However, the original expense, susceptibility to damage, and awkwardness of tarrying these instruments in steep-pitch workings has precluded their general use in everyday examinations. Although not as efficient as the electrical detector for determining small percentages of methane or as reliable because of the limitations imposed by oxygen-deficient atmospheres, the modern per¬missible flame safety lamp can, it is believed, be used safely with the rubber aspirator bulb and tubing to greater advantage and with comparative reliability in testing for gas in out-of-reach places. Slight reference to this method of introducing air into a safety lamp is made in a Bureau of Mines publication of l921,2/ and it is quite possible that the method has been utilized in some manner by individuals in American mines during the intervening years. A similar method was used in connection with a nonpermissible Wolf flame safety lamp in at least one coal mine in Japan before World War II. A major change in the construction of this lamp would bar its approval by the Bureau of Mines. An American adaptation of the Wolf lamp, developed

Jan 1, 1954

By L. Keith Hudson

The purpose of this study is to provide data that demonstrates that the Alcoa flash calciner design can be used for the decomposition of AlCl3?6H2O to A1203. Heat and material valance data for calcination provides data on the partial pressure of HCl in the off-gases. Experimentally determined data for the HCl partial pressure, over solutions expected in producing alumina from clay by the hydrochloric acid process, show that HCl can be absorbed from the off-gases into process solutions to effect crystallization of AlCl3?6H2O.

Jan 1, 1979

By Foster Fraas

Almost all minerals show irreversible changes in electrical conductivity after heating in the temperature range 100° to 800° C. This effect can be detected with only a limited number of minerals with the standard ionizing-electrode-type separator, which differentiates between nonconductors and conductors in the single-particle resistivity range of 1011 to 1013 ohms. Tests outside this range with other type separators, such as the static field type, increase the number of minerals with which the effect can be detected to almost all that were tested. Irreversibility may be the result of an alteration of adsorption layers, volatilization of surface cations or anions, or an oxidation or reduction. One example is limonite, which decomposes to hematite and passes through two minima and two maxima in conductivity in the temperature range 100° to 900° C.

Jan 1, 1959

By Eric R. Bauer

The ground control aspects of extended depth-of-cut mining are presented in this U.S. Bureau of Mines report. A trend analysis of extended cut approvals was performed. A comparative review of roof fall fatalities for extended and nonextended cut mining is included. Current ground control guidelines for extended cut approval are summarized. The problems and concerns of this extraction system are addressed, and typical extended cutting face operations are described.

Jan 1, 1993

By V. R. Shea-Albin

This U.S. Bureau of Mines report discusses elastic wave velocity and attenuation behavior as an indicator for changes in load and structural integrity of coal samples. Measuring changes in compressional (P)-wave and shear (S)-wave attenuation and velocity under uniaxial and triaxial compression tests revealed their effectiveness for distinguishing changes in applied load and structural failure of samples. The velocity and attenuation values were used in further calculations such as ratios of P-wave to S-wave values, dynamic elastic constants, normalized velocities, and attenuation coefficients to reveal trends for loading and failure. The behavior of both P-wave and S-wave attenuation and velocity together define distinct and consistent phases of load change and failure for uniaxial and triaxial tests. The S-wave velocity and attenuation illustrate changing axial load and initial development of microfractures within the sample preceding structural failure more clearly than those of the P-wave. The attenuation and velocity ratios and dynamic elastic constants (except the bulk modulus) respond to closure of small preexisting fractures within the coal sample with initial loading to failure of coal samples. The attenuation coefficients and normalized velocities reveal trends similar to those shown by velocity and attenuation.

Jan 1, 2010

By R. V. Ramani, V. T. Burgos, J. A. McClay

Cost Data Library The data retained in the Cost Data Library is of a semi¬permanent nature in that it is held in storage for immediate use with the program although its contents may require periodic evaluation to maintain it in a current status. The library is composed of six arrays containing both technical and cost data. The following description of the library input system provides the information necessary to maintain an active storage file. Array POWERA: FORMAT (8F10.0) - contains the step groupings of the power rate schedule for power cost computations. Four input data cards are required to fill this storage area. Card Column 1 1 - 10 Demand in Kilowatts for the First Step of the Demand Rate Schedule 11 - 20 Demand in Kilowatts for the Second Step of the Demand Rate Schedule y 41 - 50 Demand in Kilowatts for Fifth Step of the Demand Rate Schedule 51 - 60 Maximum Demand Level for this Rate Schedule 61 - 70 Percent Power Factor for this Rate Schedule 71 - 80 Unassigned 2 1 - 10 First Step Demand Charge, $/Kw 11 - 20 Second Step Demand Charge, $/Kw 4¬ 41 - 50 Fifth Step Demand Charge, $/Kw

Jan 1, 1975

By L. C. IlsLey

The first thing to consider in prevention of electric shock is the voltage of the circuit. No person can be sure that he will not be killed, even from a 110-volt circuit, if he makes proper contact with the circuit so as to cause the maximum current to pass through his body. As the voltage is increased to 250 volts, 500 volts, or 2,300 volts the danger from contact with the electric circuit is increased, Alternating current of the same nominal voltage is possibly more dangerous than direct current. Experience has taught us that both will cause death, and that if the fatalities from this source are to be kept low, certain precautions in the guarding of circuits must be observed.

Feb 1, 1929

By A. J. Kraemer, O. C. Blade

This report on the properties of motor fuels sold through service stations in the United States is a continuation of a series of reports made in accordance with a cooperative agreement between the Coordinating Fuel Research (C. F. R. ) Committee of the Coordinating Research Council (C. R. C.) and the Bureau of Mines of the United States Department of the Interior . The first of these reports contained data on motor gasolines sold during the winter of 1935-36 and further reports on motor gasolines sold during the succeeding summers and winters to the summer of 1941

Dec 1, 1943

By M. R. Geer

Full-seam mining with continuous mining machines in dirty coal beds may increase loss of coal in the washery refuse. At one mine mentioned in this report the loss of salable coal was increased sixfold. Cleaning trials were made on three samples of jig refuse in a dense-medium pilot plant to demonstrate the application of this process to the recovery of coal from waste. These tests demonstrated that coal could be separated from impurity with the same degree of sharpness obtained in treating raw coal by dense medium. However, the recovery efficiency achieved in treating refuse averaged distinctly lower than that possible with raw coal because of the greater proportion of intermediate-density material in the feed and the lower yield of clean coal.

Jan 1, 1955

By Erik Bengtsson

Phenol was discovered in coal tar by Runge (1)1/ in 1834 and was isolated (2) in 1841 as pure phenol by distilling the tar, extracting with caustic soda, acidifying the extract, and fractionating the tar acids. Later, o-cresol was isolated (3) through careful fractional distillation of the tar-acid mixture. The m-and p-cresols distilled within a boiling range of about 1.50 c. and had to be separated by other means. Raschig (4) fractionated the tar-acid mixture to obtain pure o-cresol, sulfonated the mixture of m-and p-cresols, and treated the cresol-sulfonic acids with superheated steam at 1200 to 1300 c. to hydrolyze the m-cresol sulfonic acid, the p-isomer was not affected at that temperature. He also attempted to make use of the different crystallizabilities of the m-and p-cresol sulfonic acids (5). When treated with sodium bisulfate and sodium pyro-sulfate at 100° to 110° C. or with sulfuric acid (90/0) at 20° C., only the m-cresol was sulfonated (6). Hoffman-La Roche (7) treated the meta-para mixture with concentrated sulfuric acid at 40° to 100° C., when m-cresol and part of the p-cresol was sulfonated, and precipitated the m-cresol sulfonic add by diluting with water. The same sort of separation may be carried out by means of 80 percent sulfuric acid at 35° C. and 35 mm pressure (8).

Jan 1, 1950

By L. C. IlsLey

A list of permissible mine equipment, tested and approved prior to Jan 1, 1937, was published in Bureau of Mines Information Circular 6942 • .ll The present list inc ludes additional equipment approved during the calendar yea r 1937. The ma terial has been listed und er the same. headings as th ose used. in Information Circular 6942. The number that appears at the beginning of each it em represents the number o f this type of ma.chine appr.oved including the machine in questi on; for instance, the miing ma.chine numbered 70 was the seventiet h co al cutting ma chine design for which approval has been isnued. All of the equipment listed represents new designs except that covered by the first item, that is, 57 under the • heading nLoading Machines and Conveyors. 11 This item covers the approval of the 500-volt design of a machine the 250-v olt design of which was approved on January 17, 1935. The system under wich these devices were tested permits the manu-. facturer., after his equipment has passed certain tests prescribed by the 'Ui"eau of Mines, to mark his equipment with a seal showing that it has been approved by the Bureau. These tests are designed to insure t hat equipments hav,e the minimum requirements for safety in use. The only object of the :Bureau in making such tests and publishing lists of permissible equipment is to help decrease the hazards of mining.

Apr 1, 1938

By J. M. Mutamansky

"Coal mine dust research throughout the world has been stimulated by the recognition of its importance in the development of coal miners' diseases, particularly coal workers' pneumoconiosis (CWP). A historical look at the problem and the present state of knowledge in this area of importance to the worldwide coal industry is presented. A summary of progress made in this area is provided and some research ideas for the future are discussed.1. INTRODUCTIONI thank Dr. Yong Won John, President of the Korean Institute of Mineral and Mining Engineers, for his invitation to address the International Symposium on Coal Mining and Safety. This presents me with an interesting opportunity to take a broad look at the research in coal mine dust and where we are going. From this broad perspective, we can all view the progress and problems that are apparent in the present state of knowledge of coal mine dust. One important element in the review of coal mine dust research and its role in miners' diseases is that of its history. The existence of diseases attributed to the mine atmosphere is often traced back to Pliny the younger in the first century A.D. His work on natural history mentioned observed human effects attributed to mine fumes and vapors. However, the subject of the effects of dust in the mine was not mentioned in published literature until 1556 when Agricola discussed the ailments of miners in his day (Seaton 1975).For many centuries, many medical ailments of the lungs were often categorized together and distinct diseases were often not recognized until more modern times. The ability to distinguish different lung diseases was limited until the discovery of X-rays in 1986. Nonetheless, Zenker in 1866 applied the term pneumonokoniosis to any disease where dust gathers in the lymphatic depots of the lungs. This term was changed to pneumoconiosis in 1932. While pneumoconiosis was defined in the 1800s, scant attention was paid to control of miners' diseases until recent decades. The first attempt to control disease through control of the mine atmosphere has been attributed to the South Africans who instituted a silica control in 1910 (Drinker and Hatch 1954)."

Jan 1, 1989