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By Mark I. Copeland

Bureau of Mines researchers investigated the combined effect of copper and tin additions on the mechanical properties of hot-rolled steels. Wrought steels containing 0.2 wt-pct C and up to 0.2 and 1.0 wt-pct Sn and Cu, respectively, were made and evaluated by conducting tensile and impact tests and electron-beam microprobe and electron microscopy examination. Tin additions did not significantly affect the tensile properties of steel at different copper contents in the hot-rolled condition. Tin lowered the copper content at which strengthening by copper precipitation normally starts, 0.8 wt-pct, and decreased the strength of steel aged at 1,022° F (550° C). The most adverse effect of tin was lowering the notch toughness of steels at most copper contents.

Jan 1, 1976

By Charles D. Haynes

Outside air for ventilating coal mines in Alabama varies considerably in both temperature and moisture content during the year. Alternate condensation and evaporation of the moisture on mine roofs may result in stresses detrimental to the strength of mine roof. It is well known that the clays in shales absorb moisture, and many investigations have noted the weakening of shales by absorption of moisture. Parker (1970) concluded that there is an annual cycle of rock deterioration in mine roof rock caused by the annual temperature-humidity cycle at the surface. He further noted that moisture reduces the strength of dry rock by one-half, that moisture added to dry rock can cause failure in compression, and that drying of wet rock causes tensile stress buildups by shrinkage. His recommendations for alleviating the moisture-temperature problem was to seal the rock in critical areas and to control ventilation so that air temperature will be lower than rock temperature. The latter recommendation will avoid condensation on the rock surfaces. Hartmann and Greenwald (1941) published the results of a very comprehensive experimental project to determine the effect of temperature and humidity changes on the behavior of mine roof. Their general conclusions included statements that roof rocks were very sensitive to moisture changes, but had low coefficients of thermal expansion. The coefficients were twice in the direction normal to the bedding plane as compared to the parallel

Jan 1, 1975

By Martin J. Gavin

"Before discussing oil shales it may be well to consider briefly the conditions surrounding the petroleum industry in the United States, because these largely explain why so much interest is being manifested in oil shales. The United States is not only the greatest producer of petroleum in the world, its output amounting to about 65 per cent of the world's total production; but is also the world's greatest consumer, using more petroleum than it produces within its own borders. For the past four or five years it has been necessary to import oil at a continually increasing rate to make up the deficit between domestic production and domestic consumption. Experts who have made a close study of the future supply and demand for, crude petroleum are satisfied that under present production practice and with the development of possible undeveloped productive areas, the gap between domestic consumption and production will steadily .increase.As possible solutions for the impending domestic shortage of oil, various expedients are receiving attention. These may be grouped under three heads, as follows:(1) Temporary measures, such as curtailment of consumption, development of more efficient methods of production, and more efficient utilization of supplies of petroleum still available. It is unlikely that there will be any great curtailment in consumption of petroleum in the United States; rather, consumption will continue to increase unless a real shortage of oil actually forces curtailment of consumption. The other two possibilities mentioned deserve, and are resolving, serious thought. Much experimental work along these lines, some of which has already yielded excellent results, is being done. Obviously, however, any of these remedies are temporary ones only, so far as regards domestic production of petroleum."

Oct 1, 1920

By D. Harrington

Approximately 6,000 coal mines are operated in the United States. All of them have in some degree the elements that are likely to contribute to an explosion, hence it is surprising that explosion disasters are not more frequent and that many mines have been operated for years and finally worked out and abandoned without experiencing an explosion. The absence of coal-mine explosions does not always indicate that effective efforts have been made to prevent them but rather that the nine has been fortunate in that the combination of circumstances necessary to cause an explosion has not existed. In view of present knowledge of the methods of preventing explosions, disasters are inexcusable and discredit the mining industry. The methods of preventing mine explosions are known to experienced, well-informed persons engaged in coal mining, yet despite this knowledge far to many coal-mine operators continue to use practices and methods that they should know have resulted in numerous explosions. Moreover, many mine workers persist in following past procedure irrespective of consequences and in breaking safety rules or indulging in practices almost certain eventually to result in disaster. Continued failure to apply known common-sense methods of accident and explosion prevention unquestionably will cell for ultimate enforcement of law.

Jan 1, 1940

By D. A. Wilson

A laboratory method for processing lead battery scrap has been developed that eliminates virtually all of the S02 emission that normally is produced when a reverberatory or blast furnace is used. The method employs a hydrometallurgical step to convert the PbS04 to PbO and CaS04 by mixing the battery scrap with a slurry of Ca(OH)2. The reaction is exothermic and goes to completion in 2 to 5 minutes at room temperature. The dried product is mixed with a KC1-NaC1 flux and carbon and reduced at 6500 C. A minimum charge ratio of 3 parts of carbon to 100 parts of battery scrap is required for reduction. The process produces lead reductions and recoveries as high as 97.0 and 94.9 percent, respectively. The KCI-NaCl flux is recovered using a standard counter-current water leach followed by evaporation.

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 O. C. Blade

The oil fields of Arkansas, all situated in the southern part of the State, have played an important part in the development of petroleum production in the northern coastal plain region of the Mid-Continent area. From the first discovery of oil in southwest Ouachita County in 1920 to December 31, 1930, a total of 480,167,5604/ barrels of crude petroleum has been produced from' this region. Development of the Arkansas fields proceeded rapidly after 1920. The El Dorado field was discovered in Union County in 1921. Drilling in Ouachita County resulted in the discovery of the Smackover field in 1922 and subsequently in the development of the whole southern area. To November 31, 1939,459 / producing wells had been drilled in 25 fields, aggregating 53,7356 acres of proved territory in 6 counties. Peak annual production for the State was reached in 1925, when 80,823,7007/ barrels was produced, resulting largely from flush production from the Smakover field, which rose td an average of 444,9507 barrel daily during that year. During 1924, 1925, and 1926 Arkansas ranked fourth among the oil-producing

Jan 1, 1940

By L. M. Demers, D. C. Kuhn

"Kuhn, Douglas C., and Laurence M. Demers. Effect of surfactant on basal and silica-induced eicosanoid production by the alveolar macrophage. Am. J . Physiol. 269 (Lung Cell. Mol. Physiol. 13): L165-Ll 70, 1995.-Infiammation and fibrosis subsequent to the inhalation of certain mineral dust particles has been suggested to result from the activation of eicosanoid synthesis by the alveolar macrophage (AM). To determine if surfactant modifies dust-induced generation of eicosanoids by the AM, we evaluated the effect of the surfactant lipid dipalmitoyl lecithin (DPL) on the production of eicosanoids by rat AM exposed to respirable silica dust in vitro. During the first 24-h exposure period, DPL alone significantly increased basal production of eicosanoids but completely inhibited silica-induced thromboxane A2 synthesis. In contrast, leukotriene B4 (LTB4 ) production was only partially reduced by DPL. During a second 24-h exposure period, LTB4 production in response to the highest dose of silica remained significantly elevated in the presence of DPL. Similar results were obtained when the surfactant preparation Survanta was evaluated. These results suggest that 1 ) DPL and Survanta independently activate AM eicosanoid production, 2) DPL and Survanta modulate the response of the AM to silica dust, and 3) L TB4 may be the most important eicosanoid mediator of the long-term effects of silica dust exposure on lung pathophysiology. THE OXYGENATED METABOLITES of arachidonic acid (AA) (here collectively termed eicosanoids) have been implicated as important regulators of lung physiology and are thought to be involved in pathophysiological sequelae such as acute respiratory distress syndrome, asthma, and the pulmonary complications of sepsis (20). This role is manifested through both direct effects on lung physiology as well as through an indirect modulatory effect on the release of other mediators of lung injury, in particular profibrotic cytokines such as the interleukins and tumor necrosis factor (15). Recently, exaggerated eicosanoid production by both the alveolar macrophage (AM) and the type II epithelial cell has been demonstrated to result from the exposure of these cells to several particulates, including crystalline silica (quartz) dust (5, 9, 17). These observations have led to the suggestion that eicosanoids play a major role in the etiology of pneumoconioses.Another secretory component of the pulmonary environment, surfactant, has been shown to modulate crucial AM functions, such as bactericidal activity and the recruitment of circulating immune cells (25). Indeed, an important feature of the lung's reaction to inhaled mineral dust is an increase in surfactant production, perhaps as a compensatory or protective response (1, 16). In addition, the alteration of the surface properties of mineral dust by surfactant or its components has been shown to influence the biochemical response of the AM to the dust, perhaps by altering the surface charge of the dust particle (11, 29, 32). And recently, Wallace et al. (28) have shown that the coating of mineral dust with surfactant, and its subsequent removal by lysosomal phospholipase, unmasks differences in dust cytotoxicity that are not apparent when AM are exposed to uncoated dust. Thus it appears that the inclusion of surfactant in in vitro exposure studies may be important in evaluating both the absolute levels of eicosanoid production by the normal and dust-exposed AM and the temporal relationship between dust exposure and the production of inflammatory mediators by the AM. Therefore, we characterized the effects of the surfactants dipalmitoyl lecithin (DPL; the primary lipid component of natural surfactant) and Survanta (a commercially available surfactant derived from bovine lung) on basal and silica-induced AM eicosanoid production during two 24-h periods after exposure to dust particles to both allow the enzymatic removal of surfactant from the particle surface and evaluate the k"

Dec 1, 1996

By Maria I. DeRosa

This Bureau of Mines report describes the Automated Breathing Metabolic Simulator and its hardware and software systems with emphasis on the role exerted by the software program subroutines in controlling the hardware mechanisms during the simulation of man's respiratory and metabolic functions.

Jan 1, 1978

By O. M. Schaus

This paper is one of a series, prepared by the Bureau of Mines and deals with the Montreal mine, one of only two active properties in Wisconsin on the Penokee-Gogebic range. The purpose of this paper is to describe the conditions of occurrence of iron ore in a particular property and to present sufficient details of equipment and production methods to convey to the unacquainted operator a correct idea of the mining practice.

Jan 1, 1930

By Manuel Gomez

Published experimental coke data from a pilot plant slot-type oven were examined by statistical regression analysis. Quantitative relationships were found to exist between the coking rate, bulk density, and fine grinding of the coal, sole-oven expansion, volatile matter, moisture, ash, and carbon con-tent of the coal and coke parameters indicative of size and strength. Regression equations developed from coke data were shown to yield computed values that were in good agreement with experimental results for 11 coke properties. Prediction equations developed were evaluated with an independent set of data. Present results indicate that the variables cited undergo much interaction and the sum of these interactions determines coke size and strength.

Jan 1, 1967

By E. J. Murphy

"INTRODUCTION This investigation is a continuation of previous work 3/4/5/ on the gaseous products of permissible explosives with and without sheaths. The range of oxygen balance of the explosives has been considerably increased. As has been shown previously, certain approximate relations exist between the volumes of gaseous products and the oxygen balance. Further systematization of the data is not feasible, since the method of theoretioal calculatln of the gaseous product is not yet satisfactorily developed. In a previously described method, 6/ it has been assumed that the explosion occurs at constant volume and that thermodynamic equilibrium is established. Apart from the presumably less important uncertainty of some of the thermodynamic data, it is not known how the confinement of the shots in the Bichel gage or the Crawshaw-Jones gage should be treated, or whether thermodynamic equilibrium is fully attained; nor can the extent to which the equilibrium composition changes during the subsequent period of expansion and cooling be judged with any reliability. Therefore, no calculations have been attempted. However, in anticipation of possible future theoretical interest and as an aid in answering practical problems, the new data are presented in the same minute detail as was done previously."

Mar 1, 1948

By K. F. Anderson

The increasing number of oil-productive reservoirs in the Ellenburger formation has emphasized the need for information pertaining to the hydrocarbon recoveries that may be obtained from such reservoirs. Most of the space available for accumulating hydrocarbons in the Ellenburger formation is derived from fractures, which makes it difficult to estimate reserves or probable recoveries. The Ellenburger reservoir in the Big Lake field was selected for study because it is one of the few near-depleted reservoirs in the area. The experience gained in operating and developing this reservoir has been and should continue to be a helpful guide to operators both in predicting recovery and establishing methods of development and operation In similar reservoirs. Development and production data were gathered from different sources. The writers have compiled and interpreted these data to estimate the ultimate recovery of hydrocarbons. In addition to the estimates of ultimate recovery, the report contains sample calculations and estimates of theoretical recovery based on different methods of operation. The calculations presented in this report indicate that the Ellenburger reservoir is 95 percent depleted and that the ultimate recovery of hydrocarbon liquid from the oil reservoir and gas cap combined will he 4-0 barrels per gross acre-foot of reservoir rock. An estimated 32 barrels of condensate per gross acre-foot of reservoir rock in the gas cap has been recovered, and the estimated ultimate recovery of crude oil will be 47 barrels per gross acre-.foot of rock in the crude-oil reservoir.

Jan 1, 1954

By W. F. Marshall

This Bureau of Mines report discusses tests conducted with four different catalytic reactor designs to determine the influences of exhaust treatment systems on emissions from diesel engines. Although there was significant differences in oxidation efficiencies at light to intermediate engine loads, all four catalysts were very effective in reducing emissions at heavy loads. Compositional determinations included carbon monoxide, carbon dioxide, unburned hydrocarbons, oxides of nitrogen, aldehydes, sulfur dioxide, sulfates, and particulate loading. Particulate size, exhaust odor intensity, and the character of the unburned hydrocarbon component were also determined.

Jan 1, 1978

By H. C. Fowler

Hydrogen sulphide associated with the gasps and vapors from certain crude oils now produced in the United States has forced a serious health and safety problem upon the petroleum industry. Although the presence of hydrogen sulphide in or occurring with Mexican crudes has been known for some time, it was not until recently that crude oils which give off poisonous amounts of hydrogen sulphide have been produced to any extent in the United State. The injurious effects of this poisonous gas were first recognized by the refiners along; the Atlantic and Gulf Coasts upon receiving shipments of crude petroleum from Mexico. The problem of combating the hazards of the gases and vapors given off by this petroleum become more important as the use of Mexican crude increased. In 1925, the Bureau of Mines and Public Health Service under cooperative agreement with the American Petroleum Institute, studied the causes rend effects of hydrogen sulphide poisoning. Bureau of Mines Bulletin 2312 is report of this investigation, and although written with special reference to refineries, it nevertheless contains much information that is of value to the producer of petroleum.

Jan 1, 1927

By Sam S. Taylor, H. M. Smith

"INTRODUCTION In most oil fields, natural gas is the major source of energy causing flow of oil to the well. The amount of gas Produced with the oil generally exceeds actual energy requirements, so that in time the gas reserve of the field becomes seriously depleted and the oil production must be stimulated by some auxiliary means. One of these is to repressure the oil formation with natural gas; or, where a gas supply is not available, often air is used.Although P.ir is a Cheap and convenient repressuring medium, its use sometimes is attended with several disadvantages. First, the return air-gas mixture decreases rapidly in fuel value, often until it can be used no longer as a source of power. At the same time, explosive mixtures may result if recycling is used, causing hazards to life and equipment. Second, some fields experience considerable trouble with the formation of emulsions which become increasingly difficult to treat. Although there is no definite proof that air repressuring always causes these emulsions, many operators are convinced that this is the case. The Petroleum Experiment Station of the United States Bureau of Mines at Bartlesville, Okla., has been interested in problems connected with air-repressuring for a number of years. Some time was spent in studying the so-called ""bad gas""--return,mixture of low fuel value. However, it appeared impossible to attack the problem successfully from this angle, and an approach was made through a laboratory--scale study of direct oxidation of crude oil."

May 1, 1934

By Deborah A. Kramer

This Bureau of Mines report presents a cost estimate of the Bayer process, which is used for virtually all cell-grade alumina production. The report will serve as a reference point to determine the economic merits of processes that have evolved from Bureau of Mines investigations on technology for producing alumina from domestic nonbauxitic raw materials. The Bayer process involves dissolving the alumina present in bauxite in a caustic solution at high temperature and pressure. After the un- dissolved impurities are removed, the solution is seeded to produce an alumina trihydrate precipitate. This precipitate is filtered, washed, and calcined to produce the cell-grade alumina product. This cost estimate is for a plant producing 1 million tons of alumina per year. The estimated operating cost is approximately $250 per ton of alumina.

Jan 1, 1983

By Robert Lee Stahl

Comprehensive field tests were made by the Bureau of Mines at the Schwartzwalder mine near Golden, Colo., to determine whether surface geophysical techniques could be used to detect and delineate faults in uranium deposits. The tests included seismic refraction, magnetometer, electrical resistivity, airborne infrared thermal scanning, and airborne photography. Of the several geophysical techniques tested in the field, horizontal resistivity profiling with electrode spacings in the range of 10 to 15 feet was most diagnostic of faults. The method is quick, inexpensive, and accurate and can be easily used by mining company personnel to detect and delineate faults.

Jan 1, 1974

By C. M. Dice

This paper is one of a series being published by the Bureau of Mines on milling methods and costs. It describes briefly the procedure followed in concentrating hübnerite or? at the Ima tungsten mine, Lemhi County, Idaho. In October 1911 the Ima mill was utilizing combined gravity-concentration, flotation, and magnetic-separation units for the recovery of a tungsten concentrate and a pyritic silver concentrate approximately 120 tons of ore averaging 0.5 percent W03 is treated daily. The concentrates produced average 66 to 67 percent WO3.

Jan 1, 1943

By C. F. Jackson

This paper describing the mining practices at a mine in the Southeast Missouri district is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The conditions, operating methods, and practice described in the following pages arc those obtaining at a property in the Southeastern Missouri lead belt, St. Francois County, Mo. This property is the eldest in the county and is a consolidation of a number of separate mines originally opened up as individual operations many years ago. Present-day operations have necessarily to be adapted to suit the older levels, stones, and pillars, and also the recovery of ore from worked over areas which was considered too low grade to mine in the earlier days constitutes a different problem than that of development and mining in virgin ground.

Jan 1, 1929