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By D. Harrington, R. R. Sayers

For several years the writers have been studying various phases of the effect of air conditions in metal mines upon underground workers ; in 1918 a short study was made in certain hot and deep mines and brief reports were issued in the Engineering and Mining Journal ( August , 1920) and in the U. S. Public Health Reports (Vol . 36 , No. 4 , January 28 , 1921 ) . In 1921 a more extended study was made (also in hot and deep metel mines ) with intent to determine the limiting conditions imposed upon underground workers by the physiological effect of various air movements , temperatures , and humidities , with and without work . It is the purpose to publish a series of short papers on this later investigation , each paper to consider one particular phase of the work . The present paper deals with the effect on body temperature and pulse rate in still air as compared with moving air of temperatures from 90 to 100° F . and 100 per cent relative humidity, the subjects at rest .

Apr 1, 1923

By H. K. Kutter

The pressure pulse generated by an underwater spark \vas investigated in relation to its potential use for rock fragmentation. The study established (1) the relation between the peak discharge current and the peak wave pressure; (2) the relationships among the peak wave pressure, the discharge voltage, and the spark gap width; (3) the type and pulse duration of the generated wave; (4) the percentage of energy transmitted in the spark as a function of spark gap width and discharge voltage; and (5) the percentage of energy converted into the pressure wave as a function of gap width and discharge voltage. Spark-generated fractures were studied in two-and three-dimensional rock and plastic specimens. The laboratory results indicated that the pressure pulse generated by an underwater spark is a potential practical tool for rock fragmentation. The paper contains an appendix describing the capacitive pressure gage specially developed for the laboratory tests.

Jan 1, 1969

By A. Gene Collins

During recent years the interest in trace and minor constituents of oil-field water, petroleum, and their associated reservoir rocks has increased. The metals copper, nickel, lead, manganese, iron, zinc, and cadmium are not determined routinely in oilfield brine analyses. Determination of these metals and subsequent correlation of these data should yield information to aid 1n the interpretation of the origin of different waters. The methods of analyzing oilfield waters have several potential applications: (1) Aiding in the search for petroleum; (2) identifying sources of intrusive brines; (3) controlling corrosion; (4) controlling produced water; increasing knowledge of the geology of subsurface formations; (5) identifying incompatible waters in waterflooding operations; (6) increasing the knowledge of the flow of oil, gas, and water in underground formations; and (7) aiding in the identification and location of valuable mineral reserves. Some brines contain enough valuable minerals to be recovered commercially.

Jan 1, 1962

By Charles L. Kimbell

Tables 16 through 19 continue the series of providing the world merchant fleet distribution by type of vessel and the ranking of the major fleets by country of registry. Table 20 this year provides a summary of the world's liquid gas carrier fleet. These vessels are included in the totals given for the world's tanker fleet, but gives a breakdown demonstrating the growth of the importance of natural gas in the world's energy commodity consumption. Panama and Suez Canals Tables 21 and 22 provide the latest available information on the transit of mineral commodities through the Panama Canal, by number of vessels, direction, and the commodities transported. Although the number of vessels transiting the Panama Canal dropped slightly (0.5%) between 1989 and 1990, the total amount of cargo moved rose by 3.6% and the amount of mineral commodities moved rose by 7.2%.

Jan 1, 1993

By R. E. Stiles

The modified perchloric--EDTA method devised by the Bureau of Mines for the determination of copper in high-grade samples gives results that are more precise and more accurate than those from the classical sulfuric-iodometric method. Although the perchloric--EDTA method is more costly than the conventional method, the savings in time alone largely offsets this difference. Specifically, the modifications wade in the more conventional procedure comprise (1) use of perchloric acid instead of sulfuric acid for dissolution of copper minerals, (2) precipitation of copper as copper sulfide from dilute perchloric acid solution, (3) wet oxidation and dissolution of the precipitated copper sulfide, (4) use of larger amounts of indicator than those employed in the Schwarzenbach method of titrating low-tenor copper solutions with disodium ethylenedinitri10-tetraacetate and murexide indicator, and (5) use of refrigeration to partially stabilize aqueous solutions of the indicator.

Jan 1, 1966

By C. Fang, D. B. Kittleson, K. L. Rubow

"Under contract to the U.S. Bureau of Mines, a study was conducted to investigate the feasibility of using the microorifice. uniform deposit impactor (MOUOI) to measure the size distribution of aerosols containing various mixtures of coal dust and diesel exhaust particles. The project objective was to determine if the mass concentration of diesel exhaust particles, in an airborne mixture of coal dust and diesel exhaust particles, could be determined on the basis of the size distribution of the two aerosols. In general, the mass of diesel exhaust particles is in the submicrometer size range while that of the coal particles lie in the larger size ranges.The MOUDI is a cascade impactor with small diameter nozzles to obtain small cut sizes and rotating impaction plates to avoid particle overloading of the deposit. For this study, a 7 stage version was used. At the sample flow rate of 30 L/min, the cut sizes were 0.10, 0.23, 0.70, 1.0, 2.6, 4.9 and 10 pm.Size distributions of aerosols generated in the laboratory and in several underground coal mines were measured. The primary emphasize of the laboratory tests was to ascertain if the diesel exhaust particles could be separated from the coal dust, regardless of mass fraction of the diesel exhaust particles in the total aerosol mixture. Diesel exhaust, from a Caterpillar Type 3304 NA diesel engine, was mixed with coal dust generated with a· TSI Model 3400 fluidized bed dust generator. Experiments showed the size distributions of the mixed aerosols exhibited two definite modes with the minimum between the two modes in the 0.7 to 1.0 um size range. Distinct modal separation was obtained as the mixture fraction of the diesel exhaust aerosols was varied from 3% to 98%.The field study was conducted in three underground coal mines, two utilizing diesel-powered equipment and the third exclusively using electric equipment. Sampling sites were selected to obtain a wide variety in the diesel exhaust and dust aerosol concentrations. Size distribution data showed these aerosols are bimodal. The mass median aerodynamic diameters of the diesel particulate mode and the coal dust mode were approximately 0.15 µm and 3 to 10 un, respectively. The results, in all cases, clearly show a separation between the two modes in the 0.7 to 1.0 µm size range with the minimum in the vicinity of 0.8 pm. The separation was found to be independent of mass fraction of the diesel exhaust particles, total particle concentration and sampling site."

Jan 1, 1989

By Joel N. Van Sant

The rapidly expanding economy of the West, with its growth of heavy industry, and increased steel production, is primarily responsible for the refractory clay industry's concern over the adequacy of the clay supply in States of the Great Plains and Rocky Mountains. Hence, the investigation by the Federal Bureau of Mines of the occurrence and use of refractory clays in North Dakota, South Dakota, Nebraska, Wyoming, Colorado, Utah, New Mexico, and Arizona has been encouraged by the major consumers and producers of this commodity. The Wyoming investigation is a part of the national program devised to close gaps in the domestic supply of specific types of clays to determine their characteristics and properties and to provide information that will assist the refractory-clay industry. Forty-two locations of clay-bearing rock in 17 areas in Wyoming were examined (fig. 1). Location 3 was not examined during this survey. Its description was taken from an earlier report. Locations 20, 21, and 22 were previously reported but were, also, examined by the Bureau. No samples were collected from these locations because field examination indicated that the shales were not refractory grade. The Hulett, Aladdin, and Newcastle areas are discussed in the section on the Black Hills district; the other 14 areas are described separately.

Jan 1, 1961

By F. P. Haver

A procedure is described for recovering both lead and sulfur from galena flotation concentrate, comprising the following steps: (1) Aqueous oxidation of the concentrate, using ferric sulfate to convert lead sulfide to sulfate and to give elemental sulfur; (2) regeneration of the ferric sulfate by electrolysis in a diaphragm cell; (3) treatment of the leach residue with ammonium carbonate solution to change the lead to an acid-soluble form and to produce ammonium sulfate as a byproduct; (4) solution of the lead carbonate in hydro-fluosilicic acid followed by electrolysis to recover the lead as metal and regenerate the acid; and (5) extraction of the elemental sulfur from the final residue with an organic solvent. About 90 percent of the lead can be recovered by the above method as 99.9-percent-pure metal, together with two-thirds of the sulfur--half in the elemental form and half as ammonium sulfate.

Jan 1, 1970

By William W. Adams

Accidents to men employed in the quarrying and related industries of the United States were more numerous, absolutely and relatively, in 1937 than in 1936. Fortunately, the entire increase was in the category of nonfatal injuries, as accidents causing death declined in number and in proportion to the number of man-hours worked. Employment increased. More men were employed, more man-days and man-hours were worked, and the average employee had more hours of work than in 1936. Reports covering all commercial operations showed that 84,094 men were employed an increase of 5.1 percent over 1936. The number of man-hours of work performed by the industry was, 158 millions, an increase of 7.6 percent. Seventy-seven men were killed by accidents, a, reduction of 14 from the year before, and 6,348 men were injured and disabled for more than the remainder of the day on which the accident occurred, 11 percent more than in 1936. The fatality rate of 0.49 per million man-hours of exposure in 1937 compared favorably with the rate of 0.62 for the previous year, whereas the non-fatal-injury rate of 40.10 was 3.2 percent higher than the rate of 38.87 for 1936.

Jan 1, 1940

By W. N. Poundstone, W. M. Merritts, B. A. Light

A joint investigation by the Bureau of Mines and the Christopher Coal Co. at the Humphrey No. 7 mine, operating in the Pittsburgh coalbed in northern West Virginia, was undertaken to gain more insight concerning the hazardous emission of methane gas in mining. This report describes the equipment, procedure, and results. Horizontal bleeder holes drilled in the faces drained large quantities of methane, eliminating downtime of mining equipment. Also, larger quantities of methane were removed by forcing 14 to 25 g,.p.m. water at 25 to 200 p.s.i. 5 pressure into the bleeder holes. In one infusion test a fluorescein dye was added to the infusion water; in later mining operations, the infusion water was traced for a distance of 1,500 feet. With vacuum pump applied to the horizontal hole the gas-flow rate increased, and the methane content decreased. Tests indicated that methane and water infused in bleeder holes traveled along the bedding planes of the Pittsburgh coalbed at a faster rate than across the planes. Methane associated with coalbeds is produced by the slow decomposition of carbonaceous material in the absence of air and the presence of water. It is lighter than air and, depending on its concentration, forms an inflammable or explosive mixture with air. It is believed that methane is entrapped in and around the pores of the coal and adjacent strata--often under great pressure. In many cases where the strata have been disturbed by geologic movements the

Jan 1, 1962

By G. R. Hopkins, E. W. COCHRANE

The number of completed petroleum refineries in the United States continued to decline in 1937 , but the total capacity to process crude oil continued to increase . These facts were ascertained in the Bureau's annual canvass of refinery capacity as of January 1 , 1938 . Several important changes were made in the census questionnaire for January 1 , 1938 . First , the basis of reckoning cracking capacity was changed from cracking stock charged to cracked gasoline produced . Although this is a definite improvement , in that it is no longer necessary to consider the yield , it is unfortunate that the data for January 1 , 1938 cannot be compared with cracking - capacity statistics since 1925. Other changes or additions included separating capacity at operating plants into that actually operating and that closed down ; collecting data on capacity added or retired during the previous year ; breaking down idle capacity according to physical status ; and separating new capacity into that built for replacement and that built to augment existing capacity . Prior to January 1 , 1938 , the total capacity of an operating plant was listed as " operating " even though some stills might have been closed down ; furthermore , the only capacity reported as being under construction was that of new plants that were being built on January 1. To make the statistics clear , the totals for the United States as of January 1 , 1938 , are given on both the old and the new bases . On January 1 , 1938 , there were 551 completed plants compared with 572 the previous year . Ten new plants were under construction on that date compared with 11 the year before . The greatest number of completed plants recorded was 632 on January 1 , 1936 ; since then , competitive conditions , particularly in the East Texas field , have been instrumental in reducing the number of small independent plants . The total crude- oil capacity of the completed refineries on January 1 , 1938 , was 4,351,151 barrels , of which 3,970 , 196 barrels ( 91 percent ) represented the capacity in actual operation and 380,955 barrels ( 9 percent ) was shut down . The " shut -down " capacity ( 199,875 barrels on the old basis ) was the lowest since pre- depression days , chiefly because numerous idle East Texas plants were removed from the list . The new method of compiling the statistics sheds considerable light on excess crudeoil capacity , which has been the subject of considerable speculation in recent years . The highest daily average crude runs to stills reached in this country was about 3,460,000 barrels in September 1937. At that time , the total crude - oil capacity was about 3,925,000 barrels . This indicates that at peak operation the excess capacity was somewhat less than

Aug 1, 1938

By E. J. Matson

This report covers the investigation of the MacArthur copper deposit and several adjacent claims in the Mason mining district; Lyon County, Nev. (fig. 1). As a part of the Bureau of Mines program of investigation and development of domestic mineral deposits, a project was begun first on the MacArthur claims. Work was done later on some adjacent claims in the immediate area, as shown by figure 2. Field work was begun by the Bureau of Mines on January 16, 1950, and completed on October 25, 1950. Eight diamond-drill holes were completed, for an aggregate of 3,414 linear feet, Analyses were made of' each drilling interval. The report includes a brief history of the district and a description of the deposits and of the work done by the Bureau of Mines.

Jan 1, 1952

By Glen C. Ware

The Bureau of Mines determined the factors involved in the corrosion of starting sheets used in the production of electrolytic zinc with the ultimate purpose of adapting zinc starting sheets to commercial practice . Under present practice , zinc is electrodeposited on aluminum cathodes and subsequently stripped for melting . The use of zinc instead of aluminum would eliminate the need to strip the deposit , thereby reducing the cost of handling and melting it , but zinc has not been suitable because it was too vulnerable to the corrosive attack of the electrolyte . Serious attack was found to be limited to the areas of the cathodes situated immediately above the surface of the electrolyte and to re - entrant corners . It was possible to avoid solution - level corrosion by immersing the starting sheets completely , exposing only a relatively heavy suspension member to solution - level attack . Zinc starting sheets could be made as reliable as aluminum and could be continued in residence for periods up to 39 days . Periods as long as a week were feasible under conditions similar to those found in commercial practice . A test of zirconium as a starting - sheet material showed that it promoted corrosion of the deposit to a lesser extent than aluminum and that the deposit adhered less tenaciously . These two properties lend themselves to the development of ways to strip deposits mechanically from zirconium starting sheets . Titanium was unsuitable for use as a starting - sheet material .

Jan 1, 1963

By D. Harrington, W. J. Fene

That fatalities from mine explosions can be very much reduced from the experience of past years if not wholly eliminated was fairly well demonstrated during the fiscal year ended June 30 , 1934 , there being only 28 deaths in the United States from explosions during this period . This is by far the lowest number of fatalities from explosions in the history of coal mining in the United States insofar as records are available . Although the frequency of occurrence of explosions has not decreased greatly during the past 6 years , there has been a marked decrease in severity , indicating that our coal -mining people are taking more effective precautions to prevent the spread of explosions . Pennsylvania is a good example of what may be done in reducing both the frequency and the severity of explosions ; by the adoption of up- to - date safety measures , Pennsylvania bituminous mines now have the enviable record of only one major explosion disaster in more than 5 years , and the one major explosion which did occur cost but 7 lives although 277 persons were exposed ; their lives were saved because rock- dusting prevented the spread of the flame and violence . Many of our other mining States are making definite progress in working mines without disastrous explosions and fires ; some of these , like Alabama , West Virginia , Indiana , Wyoming, and others now operating with few , if any , explosions , have had anything but a favorable record in the past .

Jan 1, 1935

By Leslie H. Sharp, Martin J. Gavin

Those of the oil-shale operators in this country who are sincerely attempting to make a real industry out of oil-shale developments, are anxious to obtain fundamental data on the retorting of oil-shale; particularly as regards the effect of certain variable factors in the process of retorting on the quantity and quality of products yielded from oil shales when they are subjected to destructive distillation. From careful examination of a con siderable number of suggested processes for treating oil shales and the con flicting ideas on which they are designed, it seems probable that accurate information of a fundamental nature is highly essential to the successful establishment of an oil-shale industry in this country. . Accordingly, the United States Bureau of Mines, in cooperation with the State of Colorado, is undertaking to furnish some definite and impartial information of this type through investigations now under way at the University of Colorado, Boulder, Colo. A retort for the distillation of oil from oil shale has been designed and installed, together with the necessary auxiliary equipment for controlling and determining variable factors of distillation, and for recovering and de termining the quantity and quality of the products yielded from the shales. The retort is of such a nature that conditions of retorting can be accurately . and completely controlled, and varied at will. It is not designed as a com mercial retort, but only for research purposes. A testing laboratory with equipment necessary for the examination of the shales, physically and chemic ally, and the products yielded by them, has also been fitted up . The material used in the investigations is oil shale obtained from the DeBeque, Colorado, shale field. It yields on distillation in the Bureau of Mines testing apparatus, about 42 gallons of oil to the ton, and is there fore a fairly representative sample of the shales that probably will be first worked in Colorado. The shale used will be as uniform as possible in character and oil yield and will all be obtained from the same seam at the same point, in order to avoid the introduction of unnecessary variable factors in the tests and to render results strictly comparable •

Jul 1, 1920

By William H. Lyon

In 1950 the Program Staff of the Department of the Interior undertook an exploratory study in the projection of energy requirements of the nation. This work was reported in Bureau of Mines Information Circular 7582 by H. J. Barnett. In that preliminary study Mr. Barnett, after exploring the nature of the energy economy in some detail, evolved a method for estimating how much energy will be required in the future, based on estimates of trends in efficiency of energy utilization in specific applications, the physical output of specific energy-consuming industries, size of the population, productivity advances in the economy at large, consumer preferences, and other factors. Considerable new information was developed regarding the nature of energy demands and the possible levels of requirements for each fuel under various assumed business conditions. The study analyzed the interrelationships, including substitutions, among the fuels and emphasized the need for viewing the energy economy as an integrated albeit complex whole. This exploratory study showed a need for a single comprehensive statistical re-port that would assemble and show in a uniform manner the diverse published statistical data on energy commodities now scattered through many publications. A particularly important need was for a set of historical statistics showing the production and consumption of all energy on a B.t.u. basis. As the prospective size and nature of the future energy requirements of the nation are matters of continuing importance, this report was prepared to assist further investigations of the subject. In this report the authors undertake to assemble and present in tabular form, on a uniform basis, the production and use of each of the fuels and electric energy in the United states for three census years -1929, 1939, and 1947. The year 1947, rather than a later year, was selected because it is the most recent year for which census data are available showing the consumption of fuel by each of the manufacturing industries. It is hoped that making data for these 3 years available in one re-port will provide the needed statistical background for further studies of fuel requirements and supplies.

Jan 1, 1951

By W. W. Adams

Increased employment and a lower accident-frequency rate were the outstanding features of the metal- and nonmetal-mining4 industries of the United States in 1939 compared with 1933, according to reports furnished by individual mining companies to the Bureau of Vines, United States Department of the Interior. Except for 1937, the reports for 1939 showed gains both in number of employees and number of mar -hours worked over all years since 1929. The accident-frequency rate per million man-hours of exposure to mining hazards was lower than in any year since 1925. Reports for 1939 revealed a total of 111,909 men employed in and about mines, an increase of inure than 8 percent over 1931 The total volume of labor performed at all mires was slightly more than 299 million plan-hours, an increase of mare than 10 percent over 1938. As these gains suggest, the average employee had a longer period of work in 1939, the increase amounting to r workdays per employee.

Jan 1, 1941

By Wallace W. Roepke

The Bureau of Mines studied the cutting characteristics of point-attack bits to reduce airborne respirable dust and energy during cutting. Linear cutting of two coal types using four bit types at three depths of cut with three space-depth ratios was performed with a modified horizontal milling machine using an optical particle-size monitor for respirable dust sampling. The cutting action of one bit on a rotary hardhead mining machine was mathematically analyzed and compared with the results of the linear cutting test. Airborne respirable dust per unit mass cut (specific dust) was found to be a monotonically increasing function of specific energy. Specific dust and energy decrease with increasing depth of cut. The amount of nonairborne respirable dust was 100 to 1,000 times greater than the airborne dust. The plumb-bob bit produced the most airborne respirable dust and the highest specific energy of the four bits tested. Rotary cutting was a greater dust producer and energy consumer than linear cutting because of the constantly changing depth of cut, space-depth ratio, and attack angle of the bit relative to the horizontal bedding planes. A new cutting technique is proposed to minimize the existing problems of the rotary cutting machines by providing greater production, reduced dust, and minimized methane ignition potential at the face.

Jan 1, 1976

By Robert W. Smith

The Bureau of Mines is engaged in a systematic evaluation of the thermodynamic properties of combustion gases. These studies are designed to provide basic thermodynamic information of high accuracy, facilitating the theoretical study of flame and combustion phenomena. This report is the fourth of a series4/ presenting results of the study for particular fuel-oxidant systems. These calculations have as their objective the evaluation of the constant pressure flame temperatures of methane-air, propane-air, and ethylene-air mixtures for a range of pressures.

Jan 1, 1953

By James Paone

This report on the state of the art of horizontal boring technology for underground power transmission installations was prepared by the Bureau of Mines at the request of the Department of the Interior. This paper describes the different machines and methods used in augering, impacting, pushing, drilling, and machine tunneling horizontal holes through soil and rock. A review of the borehole survey and guidance tools and techniques applicable to these methods is also given. Nonboring methods used for emplacement of power distribution and transmission lines are briefly discussed. The paper ends with a brief technical forecast, an analytical summary of the state of the art, and recommendations based on power industry needs. Horizontal boring techniques for power distribution lines installation are adequate to meet the requirements of the power industry, particularly where such burial involves relatively short distances in soil or soft rock. For burying power transmission lines, particularly in the harder rocks and over relatively long distances, horizontal boring methods are not as well advanced. Research and development as well as economic incentives to equipment manufacturers could substantially improve the state of the art. Obstacle detection and guidance systems for directing boreholes to specified targets need major improvements to meet the requirements of the power industry for underground burial of distribution and transmission lines

Jan 1, 1968