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By W. E. Robinson

A laboratory study wan made to determine whether drying and preheating Colorado oil shale with waste retort gases has any appreciable effect on its oil yield. Samples of crushed oil shale were heated at subretorting temperatures in a specially constructed electric furnace by gases similar in composition to waste gases from oil-shale retorts. The results of this study showed that preheating oil shale with nitrogen or a reducing mixture had no effect upon the oil or water yield. However, oxygen in the preheating gas caused a decrease of oil and an increase of water. In general, the oil yield decreased with (1) increase in oxygen content of the heating gases, (2) increase in temperature of the heating gas, (3) increase in heating time, and (4) decrease in the particle size of tho shale. The decrease in oil and the increase in water resulting from preheating were due to oxidation of the benzene-insoluble organic material (kerogen) rather than to oxidation of the benzene-soluble organic material (natural bitumen) in the shale, A small amount of oil was volatilized during preheating, which would constitute an additional loss if prober precautions were not taken to recover it. The results obtained in this laboratory study indicate that oil shale can be preheated without appreciable decrease in oil yield by proper selection of preheating conditions.

Jan 1, 1951

Despite modest improvements in the performance of domestic interest rates and gross national product,1 fixed investment in domestic producers' durable equipment continued to weaken during the second quarter of 1982 and declined at a 12.8 percent annual rate compared with the first quarter.2 Large declines occurred during the second quarter in expenditures on many of the major mineral-consuming industries such as aircraft, computers, agricultural and construction machinery and mining and oil field equipment. These data appear to be consistent with the low level of business investment plans for 1982 reported in the DOC's Bureau of Economic Analysis survey of expenditures on new plant and equipment.3 Domestic and foreign industrial production and mineral industry production activities continued to decline in the most recent period because of weak demand conditions (Tables 1 and 2). The U.S. mining production index declined 7.7 percent between April and June as compared with 1.2 percent for total U.S. industrial production (Table 1).

Jan 1, 1982

By Arne Landsberg

The Bureau of Mines measured the vapor pressure of FeC12 , FeBr2, FeI2, Sb, Bi, Cd, Mg, Pb, FeC13 , and VCl2 using the Knudsen-and torsion-effusion methods, and on FeC13 -NaC1 mixtures, Au2Cl6, and MgNi2 using only the Knudsen method. Apparent vapor pressures calculated from the experimental data vary with orifice size and method of determination. Reaction with residual oxygen in the instruments was noted to have an effect on the iron halide data. Vapor pressure curves plotted as log P versus 1/T (where P is pressure and T is absolute temperature) for one substance using several orifice sizes tended to converge at a single point when extrapolated beyond the experimental region. All of the data, except those of VC12, agree with previously published results. The importance of comparing effusion measurements with those obtained by other methods and the variations encountered with various orifice sizes are discussed.

Jan 1, 1977

By T. M. Garland

This report presents a more extensive perspective of the calculated profitability of developing and producing crude oil and associated natural gas by primary methods from selected onshore areas of the United States. Estimates were made for cost of drilling, completing, equipping, and producing oil wells at four depths in seven onshore producing areas. A computer program was developed for calculating the discounted cash flow rate of return for the 64 different models in each area resulting from varying the oil-producing rate and production decline rate. The results of these calculations provide data that vividly illustrate the change in rate of return to changes in well depth, initial producing rate, and production decline rate, as well as to variations in development cost and operating expense. Cost per barrel of oil produced in terms of annual cost and total cost is also discussed. Included in the report are explanations of the method of determining costs and the procedure used for profitability analysis. Summaries of all cost estimates and results of profitability analyses are presented in the appendix in tabular form for each of the seven producing areas.

Jan 1, 1972

By W. A. Calhoun

The purpose of this investigation was to develop economical mineral dressing processes for removing objectionable quantities of impurities, such as quartz and pyrite, from refractory clay deposits in east central Missouri. The presence of excessive quartz in these clays causes crazing. Pyrite causes bloating and unsightly dark blobs on the surface of fired refractory brick. The iron concentration in the proper state of oxidation may also act as nucleation centers for carbon crystal growth which can result in bursting of the refractory. Numerous deposits, representing a very large tonnage, have been examined and prospected by various refractories companies and found to contain impurities in objectionable quantities. Upgrading these clays would greatly extend our reserves of high-quality refractory clays. Wet-tabling and wet-cyclone concentration were found to be effective for removal of impurities from clays. Of the two methods, wet-cyclone concentra¬tion would be cheaper and more effective. Although wet-tabling improved the refractory properties of each clay, beneficiation by wet-cyclone produced clays of superior quality. Clay recoveries by wet-cycloning ranged from 56.1 to 81.8 percent of the weight of the crude samples, and the beneficiated clays contained from 71.9 to 94.4 percent of the total alumina. The pyrometric cone equivalent (PCE) was increased from 1 to 3 cones by wet-cycloning. The beneficiated clays also met the reheat shrinkage requirements on refiring to 1,400° C. Missouri is one of the major domestic sources of fare clay. In addition to deposits of high-grade refractory clays, there arc many deposits that contain small percentages of impurities, which render the clays unfit for the production of high-heat-duty firebrick. Development of methods to beneficiate these submarginal clays to usable materials would greatly increase commercial fire clay resources.

Jan 1, 1961

By J. E. Zeilinger

The technical feasibility of using energy from explosive ignitions of coal dust to pump water was .demonstrated in an exploratory investigation. Ignition of small amounts of pulverized coal that were dispersed in air over columns of water pumped up to 5.3 gallons of water per cycle when operated against a head of 30.75 feet. Water displacement was accomplished by either manual or automatic operation through a single cycle, and by automatic operation through a continuous series of cycles of I-minute duration. Operating through single cycles, slurries containing up to 3 pounds of coal and 4.6 gallons of water were also pumped. Possible uses of an efficient coal-fired pump would include pumping water for irrigation purposes, removing water from mines, transporting coal from mines in the form of a slurry, and pumping water to elevated reservoirs at electric powerplants so that it could be used to generate electricity during peak periods of demand.

Jan 1, 1966

By George S. Rice

In 1911 the Director of the United States Bureau of Mines instructed the chief mining engineer of the bureau , during an investigation of coal-mine safety conditions in Europe, to ask the directors of the various mine-experiment stations whether they would favor a European conference . The majority of the officials in immediate charge of experiment stations favored the plan , and Victor Watteyne, inspector general of Belgium, suggested that the United States call such a conference to be held immediately after the Eighth International Congress of Applied Chemistry, which was to assemble in New York on September 3, 1912 . Accordingly, invitations were issued by the United States Government to those countries having mine-experiment stations , namely, Austria-Hungary, Belgium, France, Germany , and Great Britain, and to those that contemplated the establishment of such stations , Canada and Mexico . All but Great Britain and Canada accepted ; Mexico designated a representative , who later found it impossible to come. The Government of Great Britain in declining, expressed regret at its inability to accept ; an informal statement was made that the opening of the experimental gallery at Eskmeals , England , occupied the attention of the officials in charge . Delegates were appointed by their respective Governments as follows: Austria-Hungary, Julian Czaplinski , royal mining engineer. Belgium, Victor Watteyne , inspector general of mines . France, J. Taffanel, director of the Lievin experiment station . Germany, Carl Beyling, bergassessor, director of Dortmund experiment station. United States , Charles E. Munroe, consulting explosives expert and George S. Rice, chief mining engineer of the Bureau of Mines . Subsequently Mr. William O'Connor , a mining engineer and mine operator of Wales , who opportunely appeared at the Pittsburgh station with letters of introduction from the South Wales Institute of Engineers and from prominent mining officials of Great Britain , was unanimously invited to take part in the meeting as an unofficial representative of Great Britain . Messrs . Beyling, Taffanel , and Watteyne were met in New York on September 3, by George S. Rice, who accompanied them to Washington, where they were welcomed by Director J. A. Holmes , of the Bureau of Mines , and where , with the delegates to the Eighth International Congress of Applied Chemistry , they were presented to President Taft . Mr. Taffanel was unfortunately called back to France just before the scheduled time of the conference on account of a mine disaster ; the other delegates , including Mr. Czaplinski , convened at Pittsburgh on the morning of September 14. Mr. Rice, representing the Director of the Bureau of Mines , acted as temporary chairman , and called the meeting to order.

Jan 1, 1914

By Robert L. Montgomery

Heats of solution of samarium (III) oxide and chloride in hydrochloric acid and of samarium (III) oxide, sulfate, and hydrated sulfate in sulfuric acid were measured. The heats of solution of this hygroscopic oxide are larger than those from the literature, probably because of more complete removal of water in the present study. From the literature value for the heat of combustion of samarium, the heats of formation of samarium (III) chloride and sulfate are -244.18 ± 0.41 and -928.5 ± 1.6 kcal./mole, respectively. The heat of hydration of the sulfate is -34.7 ± 1.0 kcal./mole. The heats of formation of other samarium com-pounds have been recalculated, using the new data.

Jan 1, 1959

By Jeffrey A. Shibe

A prototype Fire Safety Evaluation System has been developed and is ready to be evaluated by a Peer Consulting Panel and for performing field tests. The system can be used to determine combinations of widely accepted fire safety equipment and under-ground coal mine features that provide a level of safety equivalent to those required by the Code of Federal Regulations-Title 30 for underground coal mines. In this evaluation, equivalent safety performance is gauged in terms of overall level of safety provided rather than by a component by component comparison.

Jan 1, 1987

By Gerald V. Gibbs

As a part of the Bureau of Mines long-range program in asbestos, synthetic asbestiform compounds and minerals were prepared and described. Fundamental structural data on two such compounds are given in this report. Crystallographic data are provided for the synthetic isotypic compounds potassium-lead silicate, K2.Pb4 -Si8021 (I), and lead-aluminum silicate, Pb2. Pb4 .Al2Si6O21 (II). The space group symmetry 14/mmm was assigned provisionally to I and II on evidence of single crystal and piezoelectric measurements. A statistical evalua¬tion of indexed powder diffraction data revealed the cell edtes of I to be a 11.816 and c 7.932A and those of II to be a 11.723 and c 8.044A. The phases are uniaxial with observed refractive indices eD 1.790, an ?D,699 and eD 1.884, cusp 1,807, respectively. The atomic structure of I and II may be based on a complex of chains of silicon-oxygen tetrahedra lying along the c cell edge similar to the type of chain structure postulated by Pauling for scapolite. K2.Pb4.Si8021 and Pb2.Pb4 Al2Si6021 were first described by Geller and Bunting (5, 6)4 as fibrous compounds similar in crystal habit to asbestos. These authors gave powder diffraction data, although no attempt was made to find the cell edges or to index the powder diffraction patterns. Later, Shell and others (9) conducted a crystallochemical study of these fibrous silicates in search of a substitute for strategic asbestos. Their single crystal data revealed K2.Pb4 -Si8021 to be tetragonal body-centered with cell edges a 11.66, c 7.95 A. Pb2.Pb4 Al2Si6021 was concluded to be isotypic with K2.Pb4 -Si8021 on the basis of similar powder diffraction patterns, chemistry, and physical properties. No attempt was made, however, to index the powder diffraction record nor to determine the appropriate space group of either compound.

Jan 1, 1962

By F. A. Rutledge, B. S. Webber, J. M. Moss

"INTRODUCTION The United States, with its vast resources of relatively low-grade zinc been the world's leading producer of zinc -metal for many years. The expanded zinc production during the period, 1939-44, inclusive, was induced by favorable premium prices and has depleted the known ore reserves in the United States. The 1943-44 rate of zinc production cannot long be maintained in the United States, especially if premium prices are removed. Domestic zinc reserves, have been depleted to such an extent that it is doubtful if our mines will again be able to completely and continually fulfill the needs of this country.The Bureau of Mines, anticipating a postwar consumer demand for 550,000 to 750,000 tons of slab zinc and an additional 100,000 tons for use in paints and chemicals, sent two engineers to Sedanka Island in July 1945 to investi¬gate the deposits near Biorka Harbor.ACKNOWLEDGMENTIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion the Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director."

Nov 1, 1946

By James W. Ballard

The facts are generally accepted that an atmosphere containing large quantities of any dust is objectionable to breathe and that some dusts are more dangerous than others. Therefore, knowledge of the com-position of dusts is important in evaluating the hazard entailed on exposure. At present, free silica, of which quartz is the most abundant form, is considered one of the most significant dusts, from the standpoint of pneumoconiosis, and one State5/ has established permissible limits of air dustiness on the basis of the free-silica content of rock. The amount 06 free silica in materials used for rock dusting also has been limited.6/ Determination of free silica or quartz, therefore, is important.

Jan 1, 1940

By S. K. R. Iyengar

This report presents the results of a study to develop optimal designs for light-weight mine roof supports for use in underground coal mines. A load capacity of 196 kN (22 tons) and a height adjustable between 1.829 m (72 inches) and 2.438 m (96 inches) were taken as the design parameters and the design goal was a unit weighing less than 22.3 kg (50 lbs). Three alternative design concepts were explored, viz. mechanical, hydraulic, and hydro-mechanical and a total of 13 designs analyzed in detail. Steel, aluminum alloy and composites were the main potential construction materials investigated for suitability from structural, life, and safety and other considerations. The designs considered most promising for development were: (i) the mechanical screw-pin type using telescopic tubes and a fine adjustment screw thread section (ii) the all-hydraulic type, of steel, aluminum alloy or aramid graphite construction (iii) the hydro-mechanical design using telescopic tubes and a short stroke hydraulic cylinder for fine adjustment It is shown that by using realistic mathematical models for stress and deflection calculations, it is possible to reduce prop weight to the design goal. The analysis presented for all-hydraulic props is applicable to hydraulic cylinders on all mining equipment and similar machinery. This report includes the computer program and user's guide for analyzing hydraulic cylinders as well as a cross-indexed bibliography on structural composites.

Jan 1, 1978

By N. L. Wimmler

The Metaline mining district was examined in 1942 by Bureau of Mines engineers with the cooperation of geologists of the Federal Geological Survey. Because the demands of war production were rapidly depleting reserves in some of the older zinc-lead producing districts of the United States, it was decided that an attempt should be made to increase the proved or indicated ore reserves of the Metaline district. With this objective, certain areas to be explored by diamond drilling were selected. The Bureau of Mines began work on this program. January 15, 1943; work terminated September 8, 1945. Forty-five holes were drilled in seven areas, The holes ranged from 154 feet to 2,050 feet in length. Their combined length was 38,150 feet. Thirty-three of the holes were drilled in. the North Pend Oreille and the West Bella May areas.

Jan 1, 1949

By A. D. Garman

This paper presents one of a series of digests of foreign mining legislation 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 the laws of El Salvador 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 . Under the terms of the Code of Commerce ( arts . 12ff . ) , foreigners living in El Salvador can engage in business on the same terms as nationals . This involves ( = $434.00 ) - except for those with a working capital , of less than a thousand pesos inscription in the merchants ' register , which can be refused only in case of manifest disability of a permanent nature .

Sep 1, 1930

By V. T. Dow

In April 1957 the Bureau of Mines instituted a reconnaissance of titanium-and zirconium-bearing heavy sandstone deposits in the Four-State area of Utah, Wyoming, New Mexico, and Colorado. This report summarizes the study. Eighty-two deposits or groups of deposits, containing an estimated 27,920,000 tons of titaniferous sandstone, were examined in the Four-State area; 16 in southern Utah, 19 in Wyoming, 33 in New Mexico, and 14 in southwestern Colorado. The 16 deposits examined in Utah contain an estimated 1,043,000 tons with an average grade of 17.98 percent TiO2, 5.67 percent ZrO2, 20.98 percent Fe, and 0.09 percent equivalent Th02. The 19 deposits investigated in Wyoming are estimated to contain 21,873,000 tons of titaniferous sandstone having a weighted grade of 5.22 percent 702, 0.55 percent ZrO2, 24.8 percent Fe, and 0.01 percent equivalent Th02.

Jan 1, 1961

By J. J. Bourquin

"The Keely mine at Dagger, Indiana, is one of the few mines that is being operated successfully on a cooperative basis. This shaft mine is developing 133 acres of coal in the Indiana No. 6 bed, which here averages 5-1/2 feet thick and. lies about 110 feet below the surface. Thirty seven (37) miners and twenty (20) company men or day man are employed, and the daily output is around 300 tons. Practically the entire production is sold by contract for railroad use. No mining machines are used and all coal is produced by pick work.The mine was originally owned and operated by the Stockton Coal. Co. of Dugger, but about eight years ago it was leased to Mr. Roy Price. He sub-leased the property to ten miners, who formed an association known as the Dugger Mutual Coal and Mining Co., to work the mine cooperatively.At first many difficulties were encountered; the cooperative idea is an old one, but the practice was new to those interested. Some of the men were energetic, ambitious workers; others were inclined to let their associates produce the coal but wanted to share in the profits. In time, after a hard struggle and many changes in the personnel of the company, business-like methods were adopted and the mine was put on a paying basis."

Feb 1, 1983

By Donald P. Blasko

The Bureau of Mines investigated two areas of the Alaska Peninsula (Iniskin Peninsula and Becharof Lake) where oil and gas seeps were known to occur in an attempt to determine (1) whether the seeps are still active and (2) the amount of bitumen contained in the drainage leaving the seeps. The oil, water, oil-water, and gas were sampled and analyzed. Five oil samples were taken at four separate oil seeps. The API gravity of the oil ranged from 8.90 to 21.4° and the sulfur content was from 0.12 percent to 0.59 percent. Four of the seven gas samples obtained revealed fair high caloric values, ranging from 746 to 924 Btu/cu ft, and averaging 844 Btu/cu ft. A total of 44 water samples were obtained. Bitumen content of the water was as high as 9,773 mg/l at one seep, but averaged less than I mg/l where the seep-drainage water entered the Gulf of Alaska.

Jan 1, 1976

By Peter H. Toepfer

Hydraulically emplaced, classified mill sands long have been used for stope fill. Entrained water drains rapidly from this type of fill through openings between the sand grains. Slimes are removed to facilitate drainage of the water, thereby lowering dangerous hydrostatic pressures in the fill. Use of unclassified mill tailing as practiced at the Dayrock mine is a recent development and represents a fundamentally different approach to the problems of inhibiting the development of hydrostatic pressures within the stope fill. At the. Dayrock mine, mill tailing is used to form a densely packed fill of sand and slime particles relatively impervious to additional water.

Jan 1, 1952

By R. S. Dean

"INTRODUCTION The metallurgical research program of the Bureau of Mines has been somewhat disorganized, but generally advanced by the increased activities of the war period. The present report is for the purpose of summarizing the work of the Bureau in this field for the past 15 years and indicating its future plan.Fifteen years ago the Bureau turned from its pioneer work on the physical chemistry of steelmaking to an emphasis on raking a pure steel synthetically, rather than by refining, that is, :producing each of the steel 'constituents in the pure state and combining them by simple melting. Such a procedure permits the use of less high-grade ores, not only of iron, but of the ferroalloy metals, such as manganese and chromium,This program has led to extensive work on iron-ore concentration, agglomeration, reducibility of ores and agglomerates, direct reduction of iron ores and concentrates by a wide variety of processes; special refining processes for iron, the production of pure mangenese, chromium, and cobalt from low-grade ores by electrolytic processes, the production of ferrochromium, ferronickel, and ferronickel-cobalt from low-grade domestic ores, and the development of many special alloys to effectively use the new products.The status of the work in each of these fields and the future program of work, together with a bibliography of papers and patents by the Bureau staff on each of these subjects, are given."

Jul 1, 1946