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By Ralph H. Espach

In the spring of 1943, when it was evident that the Tensleep sandstone in the Elk Basin field, Wyoming and Montana, held a large reserve of petroleum, Bureau of Mines engineers obtained samples of oil from the bottom of nine wells and analyzed them for such physical characteristics as the volumes of gas in solution, saturation pressures or bubble points, shrinkage in volume caused by the release of gas from solution, expansion of the oil with decrease in pressure, and other related properties. The composition of the gas in solution in the oil was studied. The pressures and temperatures existing in the reservoir and the productivity characteristics of the oil wells were determined. The data obtained indicate that the oil in the Tensleep reservoir of the Elk Basin field has unusually varying physical characteristics, such as a saturation pressure of 1,250 pounds per square inch absolute and 490 cubic feet of gas in solution in a barrel of oil at the crest of the structure, and a saturation pressure of 530 pounds per square inch absolute and 134 cubic feet of gas in solution in a barrel of oil low on the flanks. The hydrogen sulfide content of the 6a r; in solution in the oil varies from 18 percent for oil on the crest to 5 percent for oil low on the flanks of the structure. Of even greater significance is the fact that these and other variable characteristics of the reservoir oil are related to the position of oil in the structure. Many geologists and petroleum engineers have considered all the oil in a petroleum reservoir to have uniform physical characteristics and that equilibrium conditions prevailed in all underground accumulations of oil and gas. That such is not always so is borne out by the results of the study made by the writers.

Jan 1, 1951

By John A. Ruppert

1. It has been proposed that the addition of enough limestone to an open -hearth s lag to give a CaO-3P2O5 ratio of approximately 2-followed by SiO2 firing in an oxidizing atmosphere under the proper conditions of time and temperature will result in a clinker having a magnetic phase containing a preponderance of Mn, Fe, Al, and Mg as oxides and a nonmagnetic phase consisting for the most part of a phosphorus-containing dicalcium silicate. It has been postulated further that the metal oxide phase can be recovered by fine grinding and magnetic separation. These broad principles have been substantiated by numerous clinkering operations made in an electrically fired studio-type kiln, a batch rotary kiln, and a continuous rotary kiln and by magnetic separations made in a Davis -tube separator and a laboratory-size Jeffrey-Steffensen three -roll continuous separator. 2. Quenching the clinker after firing seems to improve its grindability. Microscopic examination of the ground clinker indicates .that the oxide phase grinds down at a somewhat faster rate than the silicate phase. 3. Very fine grinding is necessary to approach liberation, of the oxide phase from the silicate phase. Grinding to ininus-325-mesh, followed by magnetic separation, gave only a rougher concentrate, which had to be reground before final separation. 4. Although the manganese content of the final concentrate was higher, there was some evidence that manganese recovery was lower from a clinker made from a flush s lag than one made from a mixture of tap and flush slags. A possible explanation is that a clinker made from a mixture of slags has a higher iron content and hence is more magnetic and more easily separated.

Jan 1, 1952

By Michael Hamilton

Mineral resources have been identified at two properties in the Ten takes RARE II area (table 1). Commodities consist of copper and silver. The deposits, in the northwest part of the study area, are hydrothermal and associated with fissure veins that developed along northwest-striking faults within the Precambrian Purcell Lava. In addition to the identified resources, there is high potential for additional copper-silver resources at these properties and moderate potential for copper-silver-lead-zinc-bariun resources at five others (table 2) in the portion of the study area that is underlain by the Purcell. There is no evidence that significant mineralization occurred in strata above or below the Purcell.

Jan 1, 1983

By P. D. Lindahl

[A cost/benefit analysis was conducted by comparing the industry cost to protective structures on low-coal face equipment with the benefits paid for injuries/fatalities considered preventable by the use of these structures. Th industry costs were based on estimates by OEM's and rebuild shops for install protective structures on new and rebuilt face equipment. The accident benefit was based on evaluations performed by the USBM Accident Cost Indicator Model. Industry wide population data were developed on low-coal face equipment and injuries/ fatalities preventable with protective structures. The results of the analysis are to be used as a tool by USBM in determining the feasibility of continuing development of cab and canopy technology for low-coal equipment.]

Jan 1, 1983

By James H. Russell

Alkalized alumina (an active form of sodium aluminate) has been considered as a sorbent for the removal of sulfur dioxide from industrial flue gases. Four rate equations, each based on a different mechanism, were compared with the results of thin-bed sorption tests. It was found that each equation agreed with the experimental results, within experimental variance, over most of the range of sorption studied. First-order rate equations were generally satisfactory in explaining both sorption and regeneration. It is concluded that the equations developed are adequate for the design of commercial fluidized beds for the sorption of SO2 from industrial flue gases and regeneration of the alkalized alumina.

Jan 1, 1970

By D. C. Dahlin

The U.S. Bureau of Mines investigated the magnetic susceptibility of minerals as a function of mag-netic field strength to determine how it might affect the potential for high-field magnetic separation as an alternative to other separation technologies. Single-mineral concentrates were prepared from specimens from the same deposit to compare magnetic susceptibilities of minerals that occur together and from specimens from different deposits to compare magnetic susceptibilities of like minerals. A vibrating-sample magnetometer with a superconducting magnet capable of producing a magnetic field of 7.16 x 106 Aim (90 kOe) was used to measure the magnetic moment of the samples. The data were then converted to specific magnetic susceptibility data and plotted as a function of magnetic field strength. Cursory studies were also completed on the effects of iron content and oxidation roasts on magnetic susceptibility in high fields. The results showed that magnetic susceptibility is essentially constant in magnetic fields above those needed to saturate ferromagnetic constituents. Although magnetic susceptibility is influenced by iron content and by thermal treatment, the changes are not large enough to influence separations in fields above 1.59 x 106 Aim (20 kOe).

Jan 1, 2010

By C. E. Wyndham

The occurrences of manganese In Alabama were reported to be widely scattered over the northeastern section of the State, and these were examined before a development project was started.2/ The most promising and available showings were chosen for further investigation, which include 1 deposit in Goshen Valley, 6 in the Rock Run area, and 2 in the northern section of Calhoun County. The work was performed by the Bureau of Mines from July 29, 1949, to February 17, 1950. The work consisted of power auger drilling 69 holes 3-1/2 inches in diameter and totaling 2,548.4 linear feet. The accuracy of samples from auger drill holes in this type of deposit was determined by sinking two shafts a total depth of 68.17 feet, from which channel samples were cut. Sixteen rotary core holes totaling 1,048.7 linear feet were drilled with a 3-inch, double-tube core barrel. Twenty-two diamond core holes were drilled with a 2-1/8-inch, double-tube core barrel and NX diamond bit. In addition to the above drilling 220.8 cubic yards of soil and rock was excavated by hand from 403.9 linear feet of trenches and 69.7 feet of test pita. A total of 206 samples were taken and analyzed for manganese, iron, cobalt, nickel, and insoluble.

Jan 1, 1953

By George Watkin Evans

The United States Geological Survey has estimated 1 that the State of Washington contains 11,412,000,000 tons of bituminous coal and 52,442,000,000 tons of subbituminous coal, in beds more than 14 inches thick. As the present rate of production is about 4,000,000 tons a year, Washington apparently contains coal enough to supply Pacific coast markets for many years. The character of the coal beds of Washington renders the production of clean coal very difficult, and a considerable proportion of the output is washed before it is marketed. In 1915 Washington ranked fifth among the States in the amount of coal washed, though only twentieth in total output. In that year 37.9 per cent of the coal produced in the State was treated in surface cleaning plants.

Jan 1, 1924

By G. L. Humphrey

Although thermodynamic data for ferrous oxide are among the most important in extractive metallurgy, adequate values have not been available until quite recently. The older data suffered not only from the usual experimental difficulties but especially from lack of the knowledge that ferrous oxide of stoichiometrical composition does not exist as a single, thermodynamically stable crystalline phase under any circumstances. This paper reports new experimental data on the heat of formation of ferrous oxide by two methods (combustion calorimetry and solution calorimetry), employing material of unequivocal composition. The results are compared with values obtained from data for the hydrogen reduction, carbon monoxide reduction, and disproportionation reactions of ferrous oxide, and a best value is selected. A table of heat and free energy of formation values of ferrous oxide to 2,000°K is given. These values are combined with available data for water, carbon monoxide, and carbon dioxide to obtain theoretical heats and free energies of reduction corresponding to the selected heat of formation. Hydrogen and carbon monoxide reduction equilibria are compared, and the differences in trend with temperature and the percentage utilization of the reductants are considered.

Jan 1, 1952

By G. W. Weems

The specific objective of this investigation was to determine the compressibility factors for helium and carbon dioxide mixtures at -10° and -20° C and pressures to 1,000 psia. A Burnett apparatus was used. Data from the experiments were treated by the method of Barieau and Dalton. Tables of compressibility factors and approximations of the virial coefficients are presented for 10 binary mixtures as well as for helium and carbon dioxide. The results follow the same trend as data previously reported.

Jan 1, 1970

By H. Kato, G. Asai, R. Blickensderfer, R. Siemens

Some relationships were established among crystallographic orientation , rollability , deformation texture , annealing behavior , slip planes , and ductile- brittle bend transition temperature of molybdenum single crystals . Six large molybdenum single crystals obtained from an ingot melted by electron beam were oriented by X - ray diffraction and rolled on crystallographic planes of low indices in a known direction . During room temperature rolling , cleavage occurred on 100 type planes . At 300 ° C the crystals were rolled to 95- percent reduction in thickness . The crystals ( 001 ) [ 110 ] and ( 011 ) [ 100 ] were most easily rolled . Pole figures were used to correlate the deformation textures of the rolled crystals with the initial crystallographic orientation . Several of the textures which developed could be explained as a rotation about a < 110 > axis of symmetry . The cube crystal ( 001 ) [ 100 ] retained much of its " cubic " orientation . The (001 ) [ 110 ] crystal developed the simplest texture , whereas the ( 211 ) [ 113 ] and ( 211 ) [ 120 ] crystals developed the most complex textures . The 1 - hour recrystallization temperature of the crystal ( 211 ) [ 113 ] was 700 ° C , which is about 300 ° C lower than that of commercial polycrystalline molybdenum . The poles of the slip planes ( as determined from gross slip lines at relatively low magnification ) tended to lie within 20 to 60 degrees of the pole of the rolling plane . The Knoop hardness was slightly dependent upon crystallographic orientation but more dependent upon rolling direction . The ductile- brittle bend transition temperature was dependent upon the rolling orientation and the dislocation density .

Jan 1, 1964

By F. E. Joyce

The Bureau of Mines studied copper-nickel minerals (mainly sulfides) of the Duluth Gabbro Complex in north-eastern Minnesota to determine their response to selective high-temperature sulfatization techniques. The gabbro, containing 0.44 percent copper and 0.13 percent nickel, was ground to minus 325 mesh and sulfatized in a heated, rotating, stainless steel bench-scale retort. Tests demonstrated that over 95 percent of the copper and 80 percent of the nickel can be converted to water-soluble sulfates, depending upon the roasting conditions employed. Yield equations were developed using regression analysis for predicting the extraction of copper and nickel between the temperature limits of 520° to 670° C, the roasting time limits of 3 to 7 hours, and S02 limits of 10 to 40 percent in S02-air mixtures.

Jan 1, 1971

By Scott W. Hazen, Richard F. Link, George S. Koch

The Mi Vida mine , Big Indian district , San Juan County , Utah , is in an ore deposit of uranium and vanadium minerals disseminated in certain sedimentary beds of the Triassic Chinle formation . Statistical analysis of assays of samples taken from the ore body affords an estimate of the grade of the ore body and provides a prediction about the direction of best mineralization beyond the sampled area . The basic data analyzed are assay results for uranium ( Uз Og ) , vanadium (V₂O ) , and lime (CaO ) from 225 channel samples cut at 79 sample points . Through the use of appropriate statistical methods , particularly regression analysis , the grade of ore may be estimated more precisely than by conventional means , and the most favorable direction to extend the mine may be predicted . Frequency distributions of assay residuals for uranium , vanadium , and lime are compared to frequency distributions of assays without regard to trend . Correlations among these variables are obtained and interpreted . The statistical methods employed illustrate certain techniques that may be used to analyze assay data from ore deposits in general .

Jan 1, 1964

By Thomas A. Davidson

The Bureau of Mines Helium Field Operations has developed a simple and accurate method for calculating the viscosity of gas mixtures. Only the composition of the mixture and the molecular weights and viscosities of the pure components in the mixture are required. The momentum fraction of a mixture is calculated from the composition. The fluidity is calculated as a quadratic function of the momentum fractions. The efficiency factor for transfer of momentum in collisions between bodies of different masses is derived and used with one empirical constant. The viscosity is the reciprocal of the fluidity. Results of the method are compared with 752 reported viscosities for 40 dilute binary systems at temperatures from -78 to 276.9°C. Using this method the average absolute deviation is 1.29%, the root-mean-square deviation is 1.99%, and the average deviation is -0.84%.

Jan 1, 2010

By G. S. Scott. R. L. Grant

Ammonium nitrate (NH4NO3), a white crystalline chemical compound composed of 35 percent nitrogen, 60 percent oxygen, and 5 percent hydrogen, has again attracted attention, due largely to the recent catastrophe on April 16 and 17, 1947, at Texas City, Tex. The fire and subsequent explosion on the steamship Ocean Liberty, outside the harbor of Brest, France, on July 28, 1947, has fur- ther increased the interest in the properties of ammonium nitrate. As a result of the Texas City disaster, several laboratories have undertaken research to determine more certainly what causes ammonium nitrate to detonate and under what circumstances. This is not the first time that ammonium nitrate has been involved in a disaster, and its properties reviewed from the standpoint of safety. The disaster at Oppau, Germany, in 1921, which involved an equimolec- ular mixture of ammonium nitrate and ammonium sulfate, prompted an intensive study in Europe and in America. In the United States the properties of am- monium nitrate are now of especial concern because very large quantites are being manufactured and shipped in interstate commerce and abroad. Many an- monium nitrate factories, which were built during the war, will manufacture increasing amounts of this compound for use as a fertilizer. It is the purpose of this report to present a brief summary and biblio- graphy of the published experimental facts about the properties and behavior of ammonium nitrate. The reader is referred to original publications for greater details of the investigative work, and for theoretical discussions. This report also includes a survey of ammonium nitrate fertilizer of the type involved in the Texas City explosions. In the past, authorities have not always agreed on the degree of hazard involved in the manufacture and handling of ammonium nitrate, as the following quotations from the literature indicate: Munroe (82) quoted the following from Turner's Chemistry (a book pub- lished in 1835): "When this salt is exposed to fire, it liquefies, emits aqueous vapor, dries and detonates." Berthelot (14) in his book, Explosives and Their Power, 1983, wrote: "Ammonium nitrate from the point of view of its volatility, and cn account of many considerations, may be regarded as a typical explosive substance."

Jun 1, 1948

By Edward Keller

The work covered by this report was undertaken at the request of Dr. J. A. Holmes, late Director of the Bureau of Mines, to whom the writer had been recommended by C. W. Goodale and E. P. Mathewson, of Butte and Anaconda, Mont. The director's offer was accepted for the honor it conferred and for the useful results that might be promulgated by the work in the technical field covered. The investigation was facilitated by permission to visit various works and sometimes by contributions of important definite information on a given subject. It is therefore with pleasure that acknowledgment of courtesies is made to the following corporations and gentlemen: Anaconda Copper Mining Co., Raritan Copper Works, Baltimore Copper Smelting & Rolling Co., United States Refining Co., American Smelting & Refining Co., B. B. Thayer, A. C. Clark, A. L. Walker, William H. Peirce, E. A. Cappelen Smith, H. H. Alexander, F. C. Newton, S. Rolle, R. "V. Deacon, N. W. Pierce, O. C. Martin, C. N. Sappington, James K Thomson, W. G. Derby, and the assistants of the writer, K. 1V.McComas and W. L. Raup. In this report considerable space has been devoted to general and theoretical principles on the ground that under modern conditions the best results in any field of activity can be attained only with the aid of an adequate knowledge of the best theories underlying the practice. The diffusion of such knowledge in the field of sampling metallic metallurgical materials appears to have been quite insufficient, and it is felt that when the principles involved are once thoroughly comprehended their universal application will be appreciated, so that it will make no difference whether pig iron or gold bullion is offered for test. It may further be noted that a discussion of the theories underlying practical methods is placed under the caption "Practical Sampling," with the idea that no one can be a practical sampler unless he is capable of analyzing his methods. No attempt has been made to advocate anyone method, but it is hoped that the analyses of all of the methods in use will show where each may be correctly and safely applied. The fact that it is possible to demonstrate the theoretical correctness of several methods indicates the invalidity of the claim that any single one of them is the standard.

Jan 1, 1916

By W. H. Oppelt

The Federal Bureau of Mines investigated combustion of lignite in domes-tic heating equipment to obtain information on equipment performance and to evaluate testing procedures. Three types of domestic heating equipment were tested, ranging from a hand-tilled, magazine-type space heater to a ram-type overfeed stoker. Lignite was readily burned in each of the three units under various test conditions. Burnoff rates determined by adding weighed charges to the magazine were found to be in error because of shrinkage of the lignite when only a portion of the magazine capacity was consumed during a test. More reliable burnoff rates could be determined by carbon-nitrogen balances. A hand-fired magazine-type space heater (Booker heater) was operated without the furnace attachment at efficiencies to 75 pct. One test series was run with minimum supervision under conditions encountered in actual household operation. No mechanical trouble was encountered.

Jan 1, 1960

By R. L. Bolmer

Driving long development raises probably is one of the most hazardous and expensive operations in underground mining. The safe handling of men and materials becomes more difficult and more time consuming in the higher sections of the raise. The efficient ventilation of these sections often is a major problem. This information circular describes a unique method by which Resurrection Mining Co, safely and efficiently completed a 622-foot vertical raise at its Irene shaft near Leadville, Colo. The method used by the company involved driving a raw, 6-foot-diameter ventilation raise and emergency escapeway, using a work cage that was suspended on a hoisting rope extended down a small-diameter drill hole. Although the method was new and experimental, the raise was completed in record time. Overall costs were less than they would have been with conventional methods. The company&apos;s initial experience suggested improvements both in design and operating technique that should prove of value to others who contemplate using the cage method of raising

Jan 1, 1958

By P. G. Guest

Many of the gases and vapors used in anesthesia form explosive mixtures with oxygen or air. Sources of ignition for these mixtures always have existed, in operating and anesthetizing areas. When ether was first introduced, candles and gas-lights and coal stoves caused fires and mild explosions of the vapor-air mixtures. Today the chief causes of ignition are electrical. Fires and explosions are still much too frequent; and, because many of the mixtures are rich in oxygen, the explosions sometimes are very violent. Obvious sources of ignition, such as electric-power sparks and arcs in open motors, switches, and receptacles, as well as exposed incandescent wires and hot plates, usually are recognized by hospital personnel and corrected. A source of ignition that is not so obvious to many is static electricity. Until quite recently the presence of this hazard in a large majority of anesthetizing areas was not even suspected. However, numerous explosions -many of them fatal to patients -have been attributed, with good reason, to sparks from static electricity. In this paper the authors present facts to show the prevalence of static electricity in the average hospital anesthetizing area, and the degree to which this easily developed electrical form of energy constitutes an explosion hazard. An effort is made throughout to explain how static electricity behaves, why it is a hazard, and why certain safety measures are needed and recommended. Following the introduction and a short general discussion of static electricity, which incorporates a glossary of pertinent electrical terms, an account is given of inspections and tests made in a number of hospitals. This account includes many suggestions that should be useful to any person who plans to make similar inspections and tests. However, a comparison of materials and equipment used with those described in the report will reveal, in many cases, the potential dangers and obviate the necessity for tests. The hospital work was supplemented by considerable laboratory research designed to determine the spark energies required to ignite anesthetic-gas mixtures and the exact amount of time involved in developing the usual static charges. The results of this research are reported and the implications examined. The paper concludes with a general discussion of static and related hazards in anesthetizing areas and of the most urgent preventative measures.

Jan 1, 1952

By W. L. Zeigler

This paper describing the milling practice of the Hecla Mining Co. is one of a series being prepared by the United States Bureau of Mines. The concentrator of the Hecla Mining Co., which utilizes combined gravity and flotation methods, is located at Gem, Shoshone County, Idaho, about 2 miles south of the Hecla mine at Burke. It has a maximum capacity of 900 tons per day and all ore treated is drawn from the company&apos;s Hecla mine. Milling ore for 1910 contained 9.7 per cent of lead, 1.2 per cent of zinc, and 4.77 ounces of silver per ton.

Jan 1, 1932