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By G. M. Kintz, E. H. Denny

Although some engineering colleges recognize the importance of instructing young engineers in industrial safety , the different institutions handle this instruction in various ways . It is believed that a recent industrial safety course , conducted at the Colorado School of Mines through the cooperation of this school and the Bureau of Mines , U. S. Department of Commerce , presents some unusual features that are of interest to other schools and to the mining public .

Sep 1, 1930

By T. D. Moore

Methane emission from two surface gob-degasification boreholes was measured by the Bureau of Mines. The investigation took place during mining of a 3,200-foot longwall panel in the Lower Kittanning coalbed in central Pennsylvania. The first hole was 500 feet from the start of mining, and the second hole was 2,200 feet. The first hole went on natural draft as soon as the longwall face passed it. This caused the methane flow in the return entries to drop 75 pct. In the 6 months required to complete the panel, the two holes emitted 69 MMcf of methane in varying percentages of concentration in air. In 3 years, the holes emitted a total of 150 MMcf of methane.

Jan 1, 1976

By G. Dale Coe, Will H. Coghill

The " periodic pincer " herein described fills a need for a device to control the rate of flow of a wet ore pulp through an orifice . Two uses of the periodic pincer to be discussed are on classifiers and on a wet ore feeder . Although the immediate necessity that brought about this device was for better operation of a miniature hydraulic classifier , in connection with an investigation of iron- ore concentration being conducted by the Federal · Bureau of Mines , with the cooperation of the University of Alabama , the device has promise of a wider field of application . In the iron - ore work , the need became so acute for a nonchoking , uniform - delivery classifier spigot that development of a suitable device was imperative .

Apr 1, 1944

By Henry Kreisinger, L. P. BRECKENRIDGE, WALTER T. RAY

The investigations of fuels conducted by the technologic branch of the United States Geological Survey had their inception at the Louisiana Purchase Exposition in 1904. By an act approved Febru- ary 18, 1904, Congress authorized the work of analyzing and testing at the Louisiana Purchase Exposition the coals and lignites of the United States, under the supervision of the Director of the United States Geological Survey. An appropriation of $30,000 was made for this purpose. In the general deficiency bill dated April 27, 1904, the sum of $30,000 was added to the appropriation. To carry out these investigations the Director of the Geological Survey appointed a committee consisting of E. W. Parker, statistician of the Geological Survey; Joseph A. Holmes, State geologist of North Carolina; and Marius R. Campbell, a geologist of the Geological Survey. Under the first act authorizing this work all of the machinery and coal for the tests was to be furnished the Government free of charge. The buildings containing the testing apparatus were all paid for out of the first appropriation. After the close of the Louisiana Purchase Exposition every Congress made an appropriation for continuing these fuel tests. These subsequent appropriations permitted the purchase of appliances better adapted for the testing work.

Jan 1, 1912

By A. C. Fieldner

In the course of its investigations on the properties of coal and in rendering fuel-inspection service to other agencies of the Government, the Bureau of Mines has accumulated a comprehensive file of coal analyses that includes data on virtually every coal field of commercial importance in the United States. As knowledge of the composition of coal is potentially valuable to every user of coal, the Bureau publishes its analytical records. Before 1921 such publications contained analyses of coal from all parts of the United States; individual analyses or average analyses of a series of shipments of coal were given with the name and location of the mine producing the coal. Beginning in 1921 the analyses were published by separate States because the quantity of data had become so great. The separate papers published to date, with Bureau of Mines Technical Paper numbers, are as follows: Alabama, 347; Arkansas, 416; Colorado, 574; Illinois, 634 and 641; Indiana, 417; Iowa, 269; Kansas, 455; Kentucky, 30S; Maryland, 465; Missouri, 366; Montana, 529; New Mexico, 569; Ohio, 344; Oklahoma, 411 ; Pennsylvania (bituminous), 590; Tennessee, 356; Utah, 345; Virginia, 365; Washington, 491 and 618 (618, published in 1941, supplements 491); West Virginia, 405 and 626; and Wyoming, 484. From time to time the various papers will be revised to include later analyses and other data. The Bureau of Mines annually receives many inquiries as to the composition of coals obtained from specific localities or, conversely, as to the localities from which a given kind of coal may be obtained. This paper presents a summary, in tabular form, of the composition of commercial coal resources of the country. Specimen analyses are given exemplifying the analysis of coal mined in each coal-producing county, or, where it was feasible, coal from each bed in each county; also, ranges of analyses, within which the composition of most of the coal represented will fall, are given where there were enough analyses to permit satisfactory determination of the ranges. In addition, the degree of metamorphism from lignite toward anthracite of much of the coal is indicated by the classification by rank. This classification reveals to more experienced users of coal some of the general properties of coal, that is, whether the flame will be long or short, whether the coal will cake in the fire, and how it is likely to behave on exposure and in storage.

Jan 1, 1942

By R. V. Higgins

The results of two separate but related studies are given. In the first study, four equations were tested; the object was to determine which would produce a curve that would best fit data points that represent a trend of declining oil production in 90 California fields. Two conventional equations (the Arps and semilog) and two novel equations (extreme-c and double semilog) were tested. The curves were first fitted to the initial 9 years of the 15-year production data and then extrapolated for 6 years to determine how well the extrapolated curve would fit the data points. The generated curves were also extrapolated beyond the last data point to predict rates of future production. The results of the first study showed that no equation was clearly superior to the others in all respects. The semilog equation resulted in the best fit to production data for the first 9 years, but the Arps and extreme-c equations produced a better fit for the extrapolated data for the period of 9 to 15 years. The Arps and extreme-c also gave more realistic production rates when extended to the point where cumulative production equaled reserves. A second study was made to determine if the least-squares technique applied to the Arps equation would result in more accurate extrapolations. The merits of the logarithmic and the nonlogarithmic forms of the Arps hyperbolic equation were also tested. For the logarithmic expression, it was found that one of the constants of the Arps equation reached a value so small or so large that the equation was not applicable to the data of 40 of the 90 California fields. The nonlogarithmic form of the Arps equation was applicable to neither the same 40 fields nor to a few additional ones. When the data and the Arps equation were compatible, the use of the least-squares technique as compared with other methods improved the extrapolation accuracy somewhat.

Jan 1, 1971

By Arthur B. Johnson

The Bureau of Mines investigated the concentration characteristics of high-clay sylvinite ores from four potash companies operating in the Permian Basin near Carlsbad, N. Mex. These ores, containing 13 to 22 percent K20 and 3 to 7 percent clay slimes, cannot be effectively processed by current commercial flotation methods because of their high slime content. A solution to this problem was shown to be the use of two-stage moderate scrubbing conditions and washing of the ore as opposed to strenuous attritioning. Bench-scale physical beneficiation techniques for recovering potash minerals and the development of ore-dressing systems by flotation resulted in obtaining acceptable product grades and recoveries. By using a coarse grind, emphasis was placed on production of premium granular and coarse products. Flotation results showed that concentrates of 58.7 to 60.4 percent K20 with recoveries of 71.0 to 83.4 percent 0f the K20 values can be obtained.

Jan 1, 1971

By G. W. Birge

This report describes the carbonizing properties of the principal coal beds of McDowell County, W. Va. Coals from 14 coal beds were selected for study: Upper Cedar Grove, Middle Cedar Grove, Lower Cedar Grove, Eagle, Douglas, Iaeger, Sewell, Welch, Beckley, Fire Creek and Pocahontas Nos. 3, 4, 5, and 9. Selection was based upon estimated minable reserves. McDowell County coals rank either as high-volatile A, medium-volatile, or low-volatile bituminous coal, and this variation in rank is reflected in the wide diversity of the carbonization properties of the coals. All coals tested were either satisfactory as mined or could be upgraded to meet present chemical standards for metallurgical coke; the coals produced strong coke, as determined by ASTM shatter and tumbler tests.

Jan 1, 1958

By W. G. Messner

Pipelines for transporting crude oil and refined products in the United States totaled 189,982 miles on January 1, 1959. This mileage was less than a 1-percent increase from the 1956 total of 188,540 miles. During the three-year period (January 1956 - January 199), 14,886 miles of new pipe and 10,649 miles of secondhand pipe was laid. Pipe taken up in the same period was 24,093 miles. The facts regarding pipeline mileage were obtained by the Bureau of Mines from pipeline companies and information provided by the Interstate Commerce Commission. Crude-oil gathering lines, as of January 1959, were 40 percent of the United States pipeline mileage and totaled 75,182 miles, an increase of 1,656 miles during the three-year period. Crude-oil trunklines totaled 70,317 miles or 37 percent of the United States pipeline mileage, a decline of 8,277 miles from the 1956 total. Some of this loss is attributed to the converting of crude lines to refined products. Refined product lines in January 1959, totaled 44,483 or 23 percent of the United States mileage, an increase of 8,063 miles during the three-year period.

Jan 1, 1959

By K. K. Kelley, W. W. Weller

The heat capacities of four crystalline silicates of barium ( BaSiO3 , BaSiO4 , Ba Si¸0 , and BaSi₂0 ) and two crystalline silicates of strontium (SrSio and Sr₂Sio ) were measured over the temperature range from 51 ° to 298° K. The results were used to evaluate the entropies at 298.15 ° K. The entropy values were joined with known heats of formation to obtain the free energies of formation of the silicates with respect to their constituent oxides at 298.15 ° K.

Jan 1, 1964

By John M. Gomes

Two molten salt systems were evaluated as electrolytes for the repetitive recovery of tungsten from tungsten oxide (W03) made by calcining commercial-grade ammonium paratungstate. Using a sodium chloride-sodium fluoride-potassium aluminum tetrafluoride electrolyte at 800° C, 1 pound of 99.8 percent tungsten was recovered for each 2.7 kilowatt-hours of energy consumed. The metal contained 1,100 ppm carbon, was in dendritic masses of spherical grains, and had an apparent bulk density of 5.41 g/cm3. T ngsten of 99.9 percent purity was won from a sodium pyrophosphate-sodium tetraborate-sodium chloride electrolyte at 1,000° C; 6.0 kilowatt-hours of energy was consumed for each pound of metal recovered. The metal contained 120 ppm carbon, was in dendritic masses of hexagonal acicular crystals, and had an apparent bulk density of 7.25 g/cm . Each metallic impurity--aluminum, calcium, copper, iron, nickel, and silicon--in the two tungsten products was 16 ppm or less.

Jan 1, 1966

By Robert K. Koch

The Bureau of Mines investigated separating HF from HF-SiF4-H2O mixtures by passing the mixed gases through a sodium fluoride slurry in an airlift scrubber and forming a mixed precipitate of NaHF2 and Na2SiF6. The oven-dried precipitate was thermally dissociated in two stages. The first stage was carried out at 400° C and dissociated NaHF2 to NaF and HF. Condensation and analysis of the evolved HF proved it to be 97 to 99 weight-percent HF containing 0.79 to 0.99 weight-percent H2O and 10 to 93 ppm silicon. The second stage was carried out at 700° C and dissociated Na2SiF6 to NaF (for recycle) and SiF4. The quantity of HF recovered from gaseous HF-H2O-air mixtures decreased with increasing relative H2O concentrations. Air was beneficial when scrubbing extremely dilute wet HF gases. At HF partial pressures of 0.24 and 0.013 mm Hg in the scrubber entrance gases, HF partial pressures of 6.2 x 10-4 and 9 x 10-6 mm Hg were obtained, respectively, in the scrubber exit gases. Scrubber efficiencies were 99.7 and 99.3 percent.

Jan 1, 1966

By F. W. Wessel

Manganiferous carbonate slates of the Cuyuna range, which are part of the unoxidized thin-budded iron formation, represent a large potential source of manganese. This report details recent bench-scale research by the Federal Bureau of Mines in applying mineral-dressing techniques to these materials in order to investigate their potential uses. Work outlined in the report was directed toward the production of concentrates usable as iron-blast furnace feed, but an equally important objective might have been to furnish an enriched feed for extractive processes for recovering manganese. Flotation concentrates were prepared that contained 11.1 percent manganese, 27.8 percent iron, and 12.2 percent silica, with recoveries of 73 percent of the manganese and 48 percent of the iron. Calculated analysis for a simulated sinter suggests a product containing 16.0 percent manganese, 40.2 percent iron, and 17.6 percent silica, with 31 percent recovery of the dry weight of the ore. The silica in the flotation concentrates was due to quartz and iron silicates. Substantial quantities of the iron silicates (stilpnomelane and smaller amounts of minnesotaite) were present in the slate, and the need to reject these minerals limited the recovery of iron. The sintered flotation concentrate would be usable as ferruginous manganese ore for iron blast-furnace feed because of its favorable manganese silica ratio. The unsintered flotation concentrates, representing 45 percent of the feed weight and containing manganese enriched in the ratio of 1.6 : 1, also could be used as feed to processes for extracting manganese.

Jan 1, 1961

By Alla D. Mah

Heat content and entropy data at high temperatures were obtained for cuprous oxide (Cu2O) and cupric oxide (CuO). Experimental results and smooth values are reported. Equations are given for heat content increments and heat capacities above 2980 K. Low-temperature heat capacity data were obtained for cuprous oxide. Evaluation of the 2980 K entropy gave, S°298.15(Cu2O) = 22.08 ± 0.10 cal/deg mole. Heat of formation values were determined for cuprous and cupric oxides. The values are: AH°298.15(Cu2O) = -40,830 ± 300 cal/mole, and AH°298.15(CuO) = -37,230 ± 150 cal/mole.

Jan 1, 1967

By W. W. Adams, T. D. Lawrence

"The National Safety Competition covering the calendar year 1934 was the tenth yearly safety contest conducted by the United States Bureau of Mines. Participating in the competition were 334 mines and quarries in 38 States. Five mining or quarrying companies, each the leader in its group for having established the best safety record during the year, were awarded the national safety trophies ""Sentinels of Safety.""Since these annual contests were begun 10 years ago by the United States Bureau of Mines the scope of the competition has been broadened materially, both as to the number of plants participating and as to the number of man-hours of exposure to accident hazards. Moreover, marked progress in the prevention of accidents has been achieved, as is indicated by an almost constant downward course in toe accident-frequency rates for the contest group as a whole during the past 10 years. On the other hand, the accident-severity rates for the group showed an upward trend during the first part of the decade and a downward trend during the latter part of the period except in 1930 and 1934; in each of those years a disastrous explosion with abnormally heavy loss of life occurred at the property of one of the participating companies.Because of the abnormal nature of the major disaster in a bituminous-coal mine in 1930 and 1934 the accident-severity rates for the bituminous group for those years are not strictly comparable with the rates for other years. The rates for bituminous mines for 1934 in the present report have therefore been computed on two bases; first, to exclude the record of the company that suffered the disastrous explosion and, second, to include the record of this company. The first rate represents the normal experience of the bituminous coal companies unaffected by the disaster and is therefore more indicative of the real trend of the accident rates for this class of mines from year to year. The latter rate shows the actual experience of all bituminous mines in 1934. The report of the competition of 1930 likewise showed the rates for the bituminous group as computed both with and without the disaster that occurred that year.The National Safety Competition is conducted by the United States Bureau of Mines in the interest of safety in the mining and quarrying industries. This object is accomplished directly through the efforts of the competing companies and their employees to win first place in the competition and thereupon receive well-merited and national recognition for their achievement. Indirectly the purpose of the contest is accomplished through studies by the Bureau of Mines of the facts contained in the accident reports which the competing companies furnish to the Bureau to enable the Bureau to compute the accident rates that are the basis for determining the winners of the contest."

Jun 1, 1935

By R. W. Hiteshue, R. W. Fridy, W. Kawa

A study of the production of coronene , a high - melting ( 440 ° C ) , highboiling ( 525 ° C) , polynuclear hydrocarbon , was made by the Bureau of Mines to determine the maximum yield obtainable by the hydrogenation of coal and coalderived materials . Experiments were made with anthracite and bituminous coals and with asphaltenes and centrifuged residue obtained from heavy oil produced in a pilot plant by the hydrogenation of a bituminous coal at 2,000 psi and 480 ° C. With anthracite , yields of coronene of 0.5 to 0.7 wt pct of moistureand ash - free coal were obtained at 6,000 to 8,000 psi , 700 ° to 750 ° C , and a residence time of 30 minutes . With bituminous coal , yields averaging 0.4 wt pct of maf coal were obtained at 6,000 psi , 800 ° C , and 30 minutes ' residence time . With asphaltene and centrifuged residue , yields of less than 0.02 wt pct of maf coal were obtained at 6,000 psi , 700 ° C , and 60 minutes ' residence time .

Jan 1, 1964

By N. A. C. Smith

[The beau of Mines made its first survey of motor gasolines sold throughout the United States in 1915, a second in 1917, and a third in April. 1919. These surveys shored that motor gasoline had become notably less volatile during each two-year interval. In order to ascertain whether this change was continuing, it was planned to institute semi-annual surveys, the first of which teas made in January, 1920. Contrary to expectations based on the previous surveys, the average volatility of the gasoline tested at this time was practically identical with that of the average volatility of the gasoline from the same districts in 1919. The next survey, made in July, 1920, showed a very marked decrease in volatility but as it has long been recognized that the volatility of motor gasoline manufactured for sale during the summer months is loss tan that of gasoline made and sold during the winter, part at least of the change was attributed to this factor. The average boiling point of the samples collected in the present survey is 263 degrees Fahrenheit, as compared with 264 a year ago. This shows that the average gasoline marketed at the present time is fully as volatile as that marketed a year ago. There has been, however, a noticeable change in the character of the product: the initial boiling point and 20 per cant point are lower than a year ago, whereas the 90 per cent and end-points are higher, which indicates a greater proportion of gasolines made by blending casing-head, or natural gas-gasoline, and naphtha.]

Jan 1, 1921

By J. D. Ramsdell

The purpose of this investigation was to determine the effects of the impurities, oxygen, nitrogen, carbon, and iron (in low percentages) on the mechanical properties of electrolytic titanium. The strength and hardness of binary Ti-O, Ti-N, and Ti-C alloys are linear functions of alloy content in the composition range investigated. Compared to oxygen and carbon, nitro-gen is the most effective strengthener and hardener, followed by oxygen, then carbon. When the carbon concentration is above 0.10 percent, carbides are present, and strength and hardness are relatively unchanged. For equivalent hardness levels, Ti-Fe alloys are stronger than binary titanium alloys containing oxygen, nitrogen, or carbon. However, the strengthening is related to the presence of transformed beta in the structure.

Jan 1, 1960

By S. M. Shelton, J. B. Zadea, M. M. Fine, T. L. Johnston

"INTRODUCTION The Mayfield manganese property is about 25 miles south of Van Horn, in Jeff Davis County, Tex. The ore deposit is developed by a large open-cut and a small stope.An 8-ton sample was received for testing; it was taker at random from material on the mine dumps and consisted of a mixture of manganese oxides, barite, and siliceous gangue minerals. The manganese occurred largely as hard, massive, crystalline psilomelane, with a small amount of pyrolusite. The gangue minerals consisted of intermixed iron-stained sand stone, quartzite, chalcedony, calcite, quartz, and barite. Chemical analysis showed 8.9 percent manganese, 3.3 percent iron, 38.4 percent silica, 6.6 percent calcium carbonate, 7.1 percent barium, 3.1 percent alumina, 0.09 percent phosphorus 0.01 tungstic oxide, and less than 0.05 percentAnalysis of selected clean pieces of manganese minerals, free of gangue, showed 48.1 percent manganese end 13.4 percent barium, of which only 0.2 percent was present as barium sulfate. This indicated a limit in concentration. Barium was also present in the gangue as a separate mineral, barite (BaSO4), which has approximately the same specific gravity as the manganese oxide."

Apr 1, 1942

By William Y. Mo

This Information Circular provides a detailed background documentation of how the Bureau of Mines projects U.S. mineral demand to the year 2000. These statistical projections serve as a quantitative basis for contingency forecasting of the low, high, and probable U.S. demand for nonfuel minerals by end-use categories and are published in the Bureau of Mines Mineral Commodity Profiles and Mineral Farts and Problems series. Aluminum is used as an example in this study.

Jan 1, 1980