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By Arnold P. Pipilen

In a study of the principal factors affecting the transport of coal-water mixtures through a centrifugal pump and a pipeline, the interrelation between solids concentration, velocity, and pressure drop was established for a bituminous lump coal (minus 2 inch) in concentrations up to 48 weight-percent. An optimum concentration was found to exist for maximum capacity of a given pipe-line, and for minimum energy requirements per ton of coal. Coal size degradation by particle fracture took place in the pump; abrasion and attrition to form fines took place in both pump and line. A novel system of studying flow of solid-liquid mixtures in pipelines by the determination of relative sound intensities was developed.

Jan 1, 1966

By Elizabeth A. Johnson

The vaporization thermodynamics of the aluminum-silicon carbides Al4SiC4 and Al8SiC7 were studied by the Bureau of Mines over the temperature range of approximately 1,500 to 1,700 K. Vapor pressures were measured by a Knudsen effusion-mass spectrometry technique in which powdered samples were effused from graphite crucibles through small orifices. For each compound, a total of six orifice diameters was tested to verify equilibrium within the cell. Aluminum, mass number 27, was the only vapor species detected over the range 4 to 200 amu. Experimental results are based on the following equations for incongruent decomposition: A14SiC4(cr) - 4A1(g) + SiC(a,hex) + 3C(gr); Al8SiC7(cr) - 8A1(g) + SiC(a,hex) + 6C(gr). The observed vapor pressure-temperature relationships determined with a cell orifice area of 2.0 x 10-3 cm2 for Al4SiC4 and 1.81 x 10-3 cm2 for A18SiC7 are the following: Log P - (-18,682/T) + 12.476, for Al4SiC4 (1,550 to 1,643 K) and Log P = (-19,308/T) + 12.421, for Al8SiC7 (1,526 to 1,784 K), with P in pascals and T in kelvins. Third-law analysis of the data provided the following heats of formation: A14SiC4 ?H at 298.15 K - -50.0 kcal/mol and A18SiC7 ?H at 298.15 K - -92.1 kcal/mol.

Jan 1, 2011

By Irving Hartmann, John Nagy

As part of a program designed to promote safety in industrial operations , the Bureau of Mines has been investigating the explosibility of numerous powdered products and dusts and studying means for the prevention of dust explosions . In a previous paper the results of a study of the inflammability and explosibility of metal powders were published . This report summarizes a similar study which has been made on various powders used in the plastics industry. The work was undertaken to provide information for a subcommittee of the Dust Explosion Hazards Committee of the National Fire Protection Association, which was charged with preparation of a code for the prevention of fires and dust explosions in plants producing or processing synthetic resins and molding compositions . The production of powders and generation of inflammable dusts are inherent in one or more steps of the manufacturing process of many resins and molding compositions, and control of the dust hazard is a major problem in the plastics industry . In the preparation of phenolic resin molding powders, for example , the solid synthetic resin is crushed and pulverized , and then blended with ground wood flour , cotton flock, or other fillers , as well as with coloring pigments . This raw mix is then passed through compounding mills , from which it emerges in the form of homogeneous sheeted stock, which is crushed , ground , and graded to form the molding powder . The number of major dust explosions in the plastics industry has been limited, but numerous small explosions have occurred, and in view of the ever -increasing volume of production the potential explosion hazard must be considered a very real one . Fortunately, this fact is realized by several manufacturers of plastic compounds , as well as by insurance companies , who are taking precautionary measures against possible accidents and during the past year or two have submitted numerous powder samples to the Bureau of Mines for explosibility tests .

May 1, 1944

By S. H. Ash

A CLAY, sand, and gravel deposit known as the "buried valley" of the Susquehanna River is situated in the Northern field of the anthracite region of Pennsylvania near Wilkes-Barre. The presence of this buried valley and the uncertainty regarding the extent and physical condition of the water-bearing valley-fill deposits have made great care necessary in mining operations to avoid breaking the strata between the mine workings and the valley-fill deposits to the extent that inundation of the mine workings would follow. The principal factor that threatens to cut short the life of the anthracite industry, to curtail production, and to affect the economic structure of the people and business dependent on anthracite for their livelihood is inundation of anthracite mines (6,7).3

Jan 1, 1950

By Alexander E. Morrow

Oxygen breathing apparatus for use in mines was introduced to the United States in 1907. Despite their intended purpose of safeguarding lives, the apparatus led to the deaths of many men because of inherent or developed defects in the equipment, lack of training,, physical shortcomings of wearers, and improper procedures. The Bureau of Mines pioneered in research and training to curb logs of life among users of such apparatus and promoted development of safer equipment and procedures. As a consequence, deaths have been far less frequent. In 1944 the Bureau issued Information Circular 7279, Loss of Life Among Wearers of Oxygen Breathing Apparatus. That publication listed the case histories of 26 deaths that had occurred since the introduction of such equipment to American mining. The author, the late G. W. Grove,3/ asserted that further loss of life could be avoided if good equipment were used, teams were properly trained, and the basic principles of safe procedure were followed. This publication is a sequel to I.C. 7279 and contains information on eight deaths among wearers of oxygen breathing apparatus that were overlooked in the original compilation. It also describes the single death that occurred since I.C. 7279 was published.

Jan 1, 1959

By Sidney Katell, JOHN H. FABER, BRYCE L. MADDOX

The information abstracted from the various publications appeared in the magazines under such headings as Business and Industry , Chemical Engineering Developments , Companies in the News , Headlines of the Month , Industrial News , Industry , Refining and Gas - Processing News , Refining News , What's Happening , and others . Although most items are related to chemical and petroleum plants , a few pertain to related fields , such as markets , drilling costs for petroleum , and field prices of crude oil . Certain articles discuss various aspects of cost -estimating procedures or description of processes . Cost bibliographies prepared by other groups are discussed in items 70 and 271. The two references can be considered as supplemental to this report , since the amount of overlap in the contents is insignificant .

Jun 15, 1957

By Wilder D. Foster

In the method used in the Health Branch of the Bureau of Mines for petro-graphic identification of the minerals in a rock, the sample is crushed, ground to a fine powder in a mortar, the powder is put on a slide, a drop of index oil and a cover slip are added, and the slide is ready for examination. The rock should be ground fine enough so that most of the particles consist of only one mineral, otherwise identification is difficult. Finally, the amounts of the minerals present in the sample are estimated to the nearest 5 or 10 percent. When quartz grains are mixed with some claylike minerals) of which by far the most common example is quartz and kaolinite in a shale, grinding in a mortar does not always separate the quartz from the kaolinite; instead, the quartz grains become coated with the kaolinite and are not visible, even after careful search. Talc acts Similarly, but muscovite and pyrophyllite do not. In evaluating the possible silicosis hazard of breathing dust from a shale, it is essential to be able to see and identify all of the quartz grains, as the other minerals present are relatively innocuous.

Jan 1, 1949

By D. C. Dahlin

To identify and characterize potential domestic chromium resources, the Bureau of Mines investigated podifom chromite deposits along the Border Ranges Fault in southern Alaska. Part 1 of this two-part report describes an extensive field investigation and preliminary resource evaluation studies by the Bureau's Alaska Field Operations Center. This paper, part 2, describes the mineralogy of 38 samples that were collected from low-grade deposits in the Chugach Mountains, on the Kenai Peninsula, and on Kodiak Island, and presents the results of laboratory batch beneficiation tests designed to concentrate the chromite. The samples are peridotites and chromites that consist primarily of variable amounts of chromite, olivine, and serpentine. They were beneficiated by a sequence of grinding, sizing, and gravity concentration operations. Twenty-four high-chromium or marginal high-chromium chromite concentrates, six high-iron or marginal high-iron chromite concentrates, and five submarginal concentrates were produced with chromium recoveries that ranged from 37 to 95 pct. Three very low-grade samples were not beneficiated. These results indicate that several of the de- posits may be significant chromium resources, Potential precious metals association with the chromite was also investigated. Analysis of these samples indicates that the chromite deposits are not good platinum sources.

Jan 1, 1985

By John D. Bardill

This report covers the magnetic surveying done in the Plattsburg area , which was part of a general survey, of magnetite deposits in New York State . Other areas being surveyed are the Star Lake district , St. Lawrence County ; Brewster district , Putnam County; and the Sterling district , Orange County. Reconnaissance indicated an area about 3 miles long and 1,200 feet wide , but detailed surveys have been completed on only a portion of that area . In several districts , surveys of this type have served as a basis in the selection of areas for exploration by diamond drilling by the Bureau of Mines .

Jan 1, 1947

By D. A. Reynolds, C. R. Holmes

The Bureau of Mines - American Gas Association ( EM - AGA) carbonization test has been used to determine the carbonizing properties of 66 American coals and a larger number of coal blends . A summary of the results obtained for the first 30 coals , including 6 blends , has been published ,4/ and results for individual coals have been reported as the investigations were completed . A bibliography of all publications pertaining to this work has been issued recently . Many of the coals were carbonized at 800 ° and 900° C. in two sizes of retorts ( 13- and 18 - inch diameters ) ; and , because the quality of coke is affected by changing the size of the retort , this report has been prepared to show the average physical properties of coke from the two sizes . This report also purposes to extend the correlation of the physical properties of coke with the rank of coal made by Fieldner and Davis in their summary of the EM-AGA tests on the first 30 coals .

Jun 1, 1942

By Alexander May

This report describes a new method of weighing based upon observing the apparent weight of an object ill two separate pure gases. The method is presented in terms of experimental data which prove its soundness, but does not attempt to show the maximum accuracy possible with this technique. The new method incorporates the underlying principle that the apparent weight of an object is a linear function of the density of the atmosphere in which the object is weighed. The coefficients of this linear function are the true mass and volume of the object. From this functional relationship the true mass and volume of the object may be determined.

Jan 1, 1970

By Earle S. Burnett

This report outlines the experimental procedures for using a Burnett apparatus to obtain compressibility coefficients for multiphase, multicomponent fluid mixtures. The conventional Burnett method is described briefly whereby multiphase compressibility data can be obtained by first determining the compressibility factor, Z, as an isothermal function of pressure alone. Then starting at conditions of temperature and pressure where Z is known, the fluid is cooled at constant volume to some lower temperature at which the resulting pressure is measured, and a corresponding value of Z is obtained from a fundamental relationship between compressibility factors, pressures, and temperatures at constant volume. The isochoric treatment of the fluid, extended to still lower temperatures and along other isochors, eventually results in compressibility determinations for the whole two-phase system thus covered experimentally.

Jan 1, 1963

By Alton B. Cook

A material balance equation was derived for calculating (1) the initial oil volume and (2) the relationship of average reservoir pressure to net gas in storage in reservoirs used for natural gas storage operations. The equation is also applicable to secondary-recovery operations where reservoirs are completely repressured and gas cycled. Using this equation minimized two probable sources of appreciable error in conventional material balance calculations: inaccurate measuring of and accounting for produced gas, and differences between true reservoir pressure and average reservoir pressures as derived from bottom-hole pressure measurements. A new procedure is presented for calculating water encroachment. By solving the conventional material balance equation and the derived equation for gas storage simultaneously, the values for initial oil in place and net water encroachment can both be determined.

Jan 1, 1966

By W. J. Long

As a part of the strategic mineral exploration program, examining engineers of the Bureau of Mines collected samples of ore from four manganese properties in Yavapai, Yuma, Maricopa, and Mohave Counties, Ariz. As all of the ores were too low in grade to be acceptable by manufacturers of ferromanganese beneficiation studies were made to determine the amenability of the ores to concentration.

Jan 1, 1948

By Paul E. Bennett, James S. Browning, Thomas L. McVay

Continuous 1.0- to 1.5 - ton - per - hour pilot plant flotation tests were made to determine the technical and economic feasibility of recovering beryl from flotation tailing being produced at the spodumene concentrator of the Foote Mineral Company , Kings Mountain , N.C. Best results were obtained when using an acid circuit and amine - type cationic reagents to float a bulk beryl - feldspar concentrate and then selectively floating the beryl away from the feldspar , using a petroleum sulfonate collector . About 77 percent of the beryllium in the pilot plant feed was recovered in a concentrate containing 6.42 percent BeO . The capital cost of an integrated flotation plant capable of treating 500 dry tons of spodumene mill tailing per day for recovery of beryl and feldspar is estimated at $ 210,000 . Indicated direct operating costs for the plant were $ 1.52 per ton of dry spodumene flotation tailing treated . This approximated the value of beryl recovered , but potential profits of about the same magnitude lie in concurrent recovery of marketable spodumene and feldspar byproducts .

Jan 1, 1964

By Alla D. Mah

Relatively pure aluminum nitride (AIN) recently has been prepared in sufficiently large amounts to permit a variety of experimental studies.4/ Several mechanical and chemical properties have been investigated, which show that this substance has good potentialities as a container for liquid aluminum, gallium, and boric oxide. The present work by the Bureau of Mines was undertaken to obtain thermo-dynamic data pertinent to the calculations regarding thermal stability and reactivity of aluminum nitride. The following measurements were made: (1) determination of the heat of formation from the elements at 298.15° K.; (2) determinations of the heat capacity over the temperature range 51° to 298.15° K. and the evaluation of the entropy at 298.15° K. therefrom; and (3) determinations of the heat content over the temperature range 298.15° to 1,800° K. These data are combined to obtain free energies of formation from the elements between 298.15° and 2,000° K.

Jan 1, 1961

By W. C. Phalan

"Prewar Conditions:Metallic magnesium may be considered a war metal, but a war metal with a future, so far as the industry in the United States is concerned. Its production in the United States prior to 1915, on a commercial scale, was negligible, but imports prior to that year may be taken as a gaze of the demand for the metal. Unfortunately, magnesium was not listed separately by the Department of Commerce prior to the war, among the importations, but was included with other metals, as follows: ""Barium, calcium, magnesium, sodium, and potassium, and alloys of which said metals are the component materials of chief value."" However, the imports of metals enumerated other than magnesium were probably small, so that the importations under the above caption may be considered chiefly metallic magnesium in one form or another and, therefore, is an approximate gage of the demand for the metal in the United States. These imports were as follows:These figures are so close that they give a good idea of the figures for the respective calendar years.Of this prewar use, it has been estimated that about 85 per cent was used annually and in approximately equal quantities in the production of (1) flash-light powder, (2) fire works, (3) aluminum casting work, and (4) nickel and nickel-copper alleys, such as monel metal, etc. The re¬maining 15 per cent was employed for general uses, such as deoxiding brass and other copper alloys in foundry work, and to a small extent in laboratory and research work."

May 1, 1920

By R. L. Brown, H. G. Berger, E. F. Pohlman

"The Bureau of Mines in cooperation with the American Gas Association investigating the relation of properties of gas oils to the gum-forming properties of carbureted water gas. The present report deals with the effects of operating practice on the composition of the light oils from carbureted water gas. A general outline of the gummy meter problem has been presented in a previous paper.*Carbureted water gas is a mixture roughly of 80 per cent water gas by volume and 20 per cent oil gas. The latter, though small in relative volume, supplies more than half of the heating value of the gas under the present-day standard. Therefore, it is logical that the oil used in the carbureting process and the operating practices involved should be subjected to scientific study. Many investigations***** bearing on the aspects considered in this paper have been carried out in the past."

Oct 1, 1923

By J. Hamilton Duffy

This is the first of, a series of papers describing dredging methods and costs in recovering sand and gravel from the beds of rivers throughout the United States and deals directly with the methods employed and costs obtained by the Ohio River Sand Co. near Louisville, Ky. ACKNOWLEDGMENTS The author wishes to acknowledge the assistance of J. R. Thoenen, mining engineer of the Bureau of Mines, in the collection of data and compilation of this report.

Jan 1, 1931

By Launa G. Mallett, Jr. Brnich

Overview: The first step to emergency preparedness and maintaining a safe workplace is defining and analyzing hazards. Although all hazards should be addressed, resource limitations usually do not allow this to happen at one time. Risk assessment can be used to establish priorities so that the most dangerous situations are addressed first and those least likely to occur and least likely to cause major problems can be considered later. Purpose: This training package was developed to assist instructors as they (1) determine how to use risk assessment to improve safety preparedness and (2) present risk assessment concepts and tools to trainees. The concepts and tools presented here can be applied to any mine hazard.

Jul 1, 2003