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By John W. Moore

The discovery of porphyries in petroleum by Treibs (17-19) is one of the most significant achievements relating to the origin of petroleum. The presence of these remnants of chlorophyll and hematin in petroleum has immediate practical interest in several aspects of the petroleum industry. Because of their interfacial activities and film-forming tendencies, the metal-porphyrin complexes may be expected to affect the wettability of petroleum-reservoir rock surfaces and influence the flow of fluids in these reservoirs. Also, studies of the relationship of trace elements and porphyrins in petroleum may be expected to yield valuable information on source beds and petroleum migration. Finally, the extreme stability of several metal-porphyrin complexes complicates removal of these metals from some petroleum stocks where they exert deleterious effects on processing and utilization. Metal-porphyrin complexes are commonly associated with the asphaltic residues of crude oils in which they occur (8, 9, 15). However, investigations in this and another laboratory (15) show that small amounts of these complexes often remain in partly refined petroleum products, such as thermally cracked distillates and deasphalted stocks.

Jan 1, 1957

By John B. Gayle

During studies of the various methods for determining and specifying the factors that indicate whether a particular coke is better or worse than other cokes for metallurgical uses, questions arose as to the precision of screen-analysis tests on coke. Although the usual index of precision, the standard deviation of the test result, gives a measure of the precision of these data, the experimental determination of the standard deviation for a particular set of conditions requires tests on a large number of duplicate samples. Because this procedure necessaily involves a great deal of labor, an equation for predicting standard deviations from theoretical considerations has been developed. Results predicted with this equation agree satisfactorily with the experimental values and are applicable to tests on coal, coke, gravel, and other bulk materials.

Jan 1, 1952

By S. L. Windes

For a number of years, the Bureau of Mines conducted tests on various types of structures to determine the effect of seismic vibrations emanating from quarry blasting in an effort to determine an index of damage . Associated with these tests , occasional records were made of the characteristics of. the air blast or concussion from the explosions . Although the importance of the air - blast problem was recognized , the equipment was not designed for air -blast measurements , nor was the early research program concerned with the problem . After the ground - vibration tests had been completed , attention was turned to study of the air blast and its effect . The air - blast problem in reference to quarry and mine blasting may be divided conveniently into three phases : (1 ) Determination of the fundamental characteristics of the air blast , such as the pressure - time relationship , speed of propagation, attenuation , and the like ; ( 2) effect of blasting conditions on these air -blast characteristics ; and ( 3) determination of the conditions necessary for damage to structures . The initial step was the development of microphones suitable for recording the anticipated blast pressures. Such microphones were designed and built during 1940 , and described in technical detail for publication ( 2)3/. Briefly, the microphone adopted was a small, plate - diaphragm condenser type . The recording was through special transducer amplifiers with low -frequency response to zero cycles per second and a Duddell - type oscillograph of special design .

Feb 1, 1942

By Charles E. Munroe

At the outset of the war the uncontrolled production and possession of explosives obviously became a serious menace to the safety of persons and property and the successful conduct of military opera- tions. Even in the years immediately preceding the entrance of the United States into the Great War explosives were employed in attempts to wreck munitions plants as at Eddystone, Pa., or to inter- rupt transportation and conveyance by demolition of munition-laden cars as at Black Tom Island, N. Y., or by attacks on ships, bridges, and viaducts. Outrages with explosives, such as that which Holt inflicted on the Senate reception room, United States Capitol, were not infrequent, and often caused serious loss of life and injury to persons as well as destruction of property. The regular manufacturers of explosives were keenly alive to this menace and early took such steps as lay within their power to meet it as is shown by the following letter:

Jan 1, 1921

By L. B. Berger

Tests and observations of a Diesel-powered locomotive used for under-ground haulage, in a-clay mine were made by representatives-of the Bureau of Mines .primarily to determine the composition of the exhaust gases produced by the engine under actual haulage conditions-and to determine the effects of the operation on the quality of the mine atmosphere. In addition to ascertaining these conditional t proved interesting to analyze the test, data in regard to certain other performance, characteristics of the engine. This report presents results of tests of the mine locomotive, prefaced by a brief resume of the performance characteristics of Diesel engines to facilitate discussion.

Jan 1, 1948

By H. D. Kline

Manganese ores have been mined in the Batesville district since 1849. Although not continuous over the intervening years, production had totaled approximately 432,000 tons of manganese ore and ferruginous manganese ore to the end of 1953. The ores occur in deposits, essentially low in manganese content, distributed over an east-west belt 24 miles long and 4 to 8 miles wide, the core of which is about 6 miles north of Batesville, Independence County. Although the reserves of high-grade ores in the district are comparatively small, the large deposits of subgrade ores and low-grade manganiferous material comprise potential sources of supply of manganese that may have increasing future importance. The manganese occurs as primary oxide and carbonate minerals in relatively flat-lying limestone and shale formations in which they were originally deposited and as oxides in residual clays resulting from decomposition of the shale and lime-stone. Most of the deposits underlie from a few to over a hundred feet of sedimentary chert, but many occur in the residual clays on exposed slopes of chert-covered hills.

Jan 1, 1956

By Otis E. Perkins

This paper is one of a series being prepared for the United States Bureau of Mines to disseminate technical information retarding the methods used in mining nonmetallic minerals. The cost tabulations represent operating expenditures only and not total costs. It is recognized that publication of total costs might in many instances cause embarrassment to individual operators as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. This paper deals particularly with methods and costs of dredging, classifying materials, and transportation at the plant of the Ross Island Sand & Gravel Co. of Portland, Ore. ACKNOWLEDGMENTS The author wishes to acknowledge the assistance of Harold Blake, general manager of the company, and of A. V. Kramer, cashier in charge of the plant office.

Jan 1, 1933

By B. M. Stewart

Researchers at the U.S. Bureau of Mines conducted a long-term groundwater monitoring and site characterization program at an abandoned 10-ha, acid-producing, copper-gold tailings impoundment in north-central Washington State. The purpose was to investigate contaminant release and transport, and attenuation mechanisms in the tailings, sediments below the tailings, and gravels downgradient of the impoundment. This report summarizes the monitoring results and physical properties of the tailings, the sediments below the tailings, and the groundwater system associated with the tailings. Water samples from the vadose and saturated zones of the impoundment were analyzed for 15 constituents. Concentrations of the same constituents were determined in water samples up to 3 m beneath the impoundment and in the shallow colluvium and deep bedrock at 76, 335, and 550 m downgradient and 168 m upgradient. Constituent concentrations within the tailings are quite variable and are influenced by pH, depth of oxidation, grain-size differential (surface area), hydraulic gradient, groundwater mixing, and the presence of hardpan layers, carbonaceous material, and organic matter. Most of the metal constituents decreased to background or near-background concentrations in the farthest downgradient well.

Jan 1, 2010

By John R. Bitler

The Bureau of Mines conducted this study to provide information concerning the availability of and the demand for construction-mineral aggregates in the Baltimore, Md., Standard Metropolitan Statistical Area (SMSA). The demand is discussed with reference to the area's current consumption and estimates of the area's demand for aggregates through 1990. Estimates of aggregate supply are presented in conjunction with an examination of the geology of the area, the availability of substitutes, and the effect of transportation costs. A discussion of the constraints affecting aggregate availability precedes the conclusions and recommendations. The availability of aggregates is subject to geologic, economic, and political constraints. As of January 1974, an estimated 20,100 million tons of stone was available to meet the demand projected through 1990 (188.7 million tons). An estimated 139 million tons of sand and gravel was available to meet the demand projected through 1990 (84.3 million tons). Several alternative actions are available within the area to insure the adequacy of the stone supply and to increase the supply of sand and gravel: (1) The establishment of special mineral resource zones; (2) the application of sequential land use techniques; and (3) the exploration of previously undeveloped regions.

Jan 1, 1975

By H. L. Gibbs

A portable radon monitoring instrument capable of making on-the-spot measurements of the radon gas content of uranium mine atmospheres was designed and constructed. The monitor was tested in the laboratory and in operating uranium mines. Good correlation was obtained between the monitor readings and radon measurements made on mine atmosphere samples taken in radon bottles.

Jan 1, 1973

By L. J. Kane

Applications are described of various methods for determining the weight concentration and physical properties of solid and liquid impurities of gases in connection with problems encountered in synthesis-gas production. Of special interest among these methods may be listed: 1. A method developed for determining, the weight concentration of solid and liquid impurities in. hot, crude synthesis gas containing a high concentration of moisture. 2. A method developed for the same purpose but for highly purified synthesis gas or atmospheric air. 3. A method for obtaining a uniform dispersion of dry duet or, a microscope slide for particle-size determination or other purposes.

Jan 1, 1954

By W. O. Vanderburg

The leasing or tribute system has been an important factor in the development of our metal-mining industry, particularly in the gold and silver mines of the Western States. It has received its widest application in. the early history of many camps and in the last stages of many mines. The system is especially adapted to mining where the ore's occur in narrow veins or are erratically distributed in small bunches or pockets so that selective mining, hand sorting, screening, or hand cobbing is required to produce shipping or milling-grade ore. The leasing system is also applicable to the development of prospects where the owners are unable or unwilling to assume the risks of searching for ore. The virtue of the system lies in the opportunity it affords miners with little capital to get started; at the same time, it rives owners an opportunity to have their property developed at small cost.

Jan 1, 1934

Develop geophysical techniques suitable for enhancing miner safety. Specifically, to use geophysical methods to detect hazardous conditions in a rock mass in deep underground mines as well as to assess the mechanical integrity and monitor changes of the rock.

Jan 1, 1997

By Lucien Eaton

This paper describing the mining practices at Mine No. 1, Menominee Range, Mich., 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. It is felt that the publication of this information will be of interest and value to the mining industry at large and especially to operators whose mining conditions are similar to those described. ACKNOWLEDGMENTS The author is indebted to the superintendent, engineer, and mining captain of Mine No. 1 for much of the information presented.

Jan 1, 1929

By Robert H. Townsend

The following paper discusses the mining, transportation, and crushing methods, with costs, at the San Andreas plant of the Calaveras Cement Co. It is one of a series, prepared for and published by the U. S. Bureau of Mine describing methods used in cement-rock quarries throughout the country. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total cost. It is recognized that publication of total costs mightin some instances cause embarrassment to individual producers as well as to the industry as a hole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost-tabulations shall ensue.

Jan 1, 1933

By Jean M. Kenney

Frequencies of haulage-related accidents in metal and nonmetal surface mines for the years 1988 through 1990 were investigated and compared with those of non-haulage-related accidents. This study was part of the U.S. Bureau of Mines program to improve mining haulage safety. Data were obtained through the U.S. Bureau of Mines Accident Data Analysis (ADA) program. The chi-square test was used to compare frequencies of haulage-related and non-haulage-related accidents for each of the following variables: degree of injury, age, total number of years of mining experience, and shift time. Significance was determined for degree of injury between haulage-related and non-haulage-related accidents. Age of injured did not vary significantly between haulage-related and non-haulage-related accidents, but total number of years of mining experience was found to be significant. Shift time for the accident proved to vary significantly between haulage-and non-haulage-related accidents. Events causing injury for haulage-related accidents were tabulated, and the most frequent determinants of haulage-related accidents were identified. Accident descriptions for both fatalities and permanent disabilities were studied, and the primary causes of these accidents were identified. These findings suggest that haulage-related jobs are among the most dangerous when considering accidents experienced by all workers in the metal and nonmetal surface mining work force.

Jan 1, 1993

By H. D. Jacobs

The Bureau of Mines undertook a research program to insure an adequate supply of iron raw materials for future iron and steel making needs. A sample was obtained of oxidized taconite from the western Mesabi Range in Minnesota, and the metallurgical response of the taconite to beneficiation by a process that included selective flocculation-desliming-cationic flotation was evaluated. The sample contained 35.3 pct iron and represented approximately 2 billion tons of crude material. Selective flocculation and flotation were evaluated in a pilot plant with a feed rate of 900 Ib/hr. Concentrates averaging 61.7 pet iron and 5.1 pet silica were obtained, with an accompanying iron recovery of 67.2 pet. About 83 pct of the process water requirements were reclaimed from the slime and froth tailing and then recycled.

Jan 1, 1980

By P. L. Woolf

Seven evaluation tests with blast furnace iron bearing burden materials are described. The effects of pellet strength, fines in the burden, decreasing slag volume, pellet size, eliminating stone with superfluxed sinter, and eliminating stone by prefluxing the pellets were determined. Fluxed pellets and fluxed sinter made with the same ore fines were compared. The tests were conducted under cooperative agreements between the Bureau of Mines and North American steel companies. The objectives were to improve blast furnace practice, expand and develop understanding of the operation and theory, quantify the effects of changes, and explore the limitations of operability. This work was part of an extensive program of blast furnace research in experimental blast furnaces at Bruceton, PA conducted in the years 1958 to 1967.

Jan 1, 1984

By T. T. Campbell

Although secondary recovery of lead and lead-tin alloys has been common practice in the United States during recent years, there is little published in-formation concerning recovery techniques. Available information does not cover metal recovery from wet dross skimmings. This investigation by the Bureau of Mines was undertaken to develop techniques that would allow lead-tin alloys to be recovered from wet dross skimmings containing large amounts of zinc chloride. A process was developed, on a laboratory scale, for recovering lead-tin alloys from wet solder dross skimmings. Straight water leaching, either with or without a second leaching operation carried out with a Na2C03 addition for removing chloride, produced a dross that could be smelted without further treatment. Overall recoveries averaging 92 percent of the metal values in the dross were obtained in the form of lead-tin alloys, which had an average tin content of 16 percent and lead content of 84 percent. The recovered alloy contained less than 0.02 percent zinc, as determined by both chemical and spectrographic analyses.

Jan 1, 1956

By A. F. Colombo, D. W. Frommer

Bench- scale tests were made to determine the applicability of flotation as a means of upgrading finished and semifinished magnetic concentrates prepared from reductively roasted iron ores . Both anionic and cationic flotation methods were used to remove siliceous gangue from the magnetic concentrates and produce upgraded products . Seven magnetic concentrates , containing from 6.7 to 13.7 percent SiO2 , were improved by the flotation treatment , yielding final concentrates containing less than 6.0 percent Si02 . Cationic flotation methods were studied on four of the seven samples ; of this group only one sample yielded better results by cationic flotation than by the anionic method .

Jan 1, 1964