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By Stephen Krickovic

A degasification experiment was conducted in a Pocahontas No. 3 coalbed mine in Virginia. It involved (1) drilling holes in the coalbed in the out-side headings of a set of five being developed in virgin area, and (2) con-ducting a methane emission rate study as mining progressed and additional holes were drilled. Degasification from all drill holes except the longest in each of the outside headings and the first three drilled (excluding the in-situ pressure hole), was erratic and inconsequential in methane emission rates. The two longest holes liberated 66 and 79 cfm of methane, which is significant for the coalbed, but such quantity lasted a relatively short time; the first three were uniform but low in methane emission.

Jan 1, 1972

By C. J. Johnson, C. J. Bise

"IntroductionCoal extraction by continuous miners (CM) is currently the most common underground method in the US industry and accounts for slightly more than two-thirds of the nation· s deep mining production (National Coal Association, 1987). Even if longwall mining should become more commonplace, it can proceed only af1er ventilation and access entries have been driven by CMs. Since an area of concern continues to be the effects of the dust generated on the health of mineworkers, this paper discusses the relationship between the elemental composition of mining-generated airborne dust sampled from the immediate ventilation return of a CM and laboratory-generated dust derived from channel samples taken from the mines.There are several potential contributions of this type of study to the coal mining industry. First after more fundamental knowledge of the causes of Coal Worker's Pneumoconiosis (CWP) is learned, the laboratory-generated respirable dust could be used to identify a potentially hazardous coal seam. Also, this study could possibly aid in understanding the fundamental causes of CWP by producing mining-simulated samples of coal dust that could be used in epidemiological studies.Further, assuming that there is no difference in the elemental composition of a drill-core sample and a channel sample from the same location a mining company could predict anew mine's respirable dust elemental composition In the immediate ventilation return by using exploratory drill core samples of the roof ,coal, and floor rock to prepare the laboratory dust. Ventilation engineers could then use engineering design and control measures during premine planning to reduce the incidence and severity of CWP by better ventilating the potentially hazardous coal seam. If this proper planning prevented any future changes to the ventilation equipment and mine design, much time and money could be saved.Scope of workTo investigate the variability of the chemical characteristics of respirable dust, airborne dust samples from eight underground coal mines located in the eastern and mid western United States were collected with eight-stage Sierra Model 298 Marple cascade impactors, as well as 25 channel samples of mined material. Each channel sample was removed from the middle of the coal face before mining occurred. Sampling of the mining-generated dust was conducted by Lee ( 1986) by sampling the entire working sections, primarily for characterization purposes, to obtain information on the locational variability of dust characteristics. Research performed for this study used the elemental analyses of the mining-generated dusts he sampled in the immediate ventilation returns of CMs."

Jan 1, 1989

By John Millhiser, Margaret Bonarek, Dennis McLaughlin

This report contains a description of the contract activities performed by ENSCO, Inc. under contract No. H0178069. The purpose of this project was to enhance the Bureau of Mine's Cableless Electronic Survey System use to aid in the drilling of long (approx. 2000 feet) boreholes in coal. This drilling is performed as part of the methane drainage program. The system that was ultimately developed was field tested and demonstrated in actual in-mine drilling activities. The significance of this system as compared to previous drill survey systems is the fact that it surveys without having to be inserted and removed for each survey point. It is so designed that it can withstand the shock and vibration experience by the drill string during drilling. This means an increased productivity is now possible in that drill operators can determine drill bit positioning in a near real-time environment.

By Raymond B. Ladoo

"The recent discovery and exploitation of petroleum territory have resulted in the enactment of new petroleum laws in most of the South American Republics. The activities in the discovery of these new fields were engendered by the knowledge of the fact that present producing fields must within well defined periods be exhausted. Oil operators were willing to take the initial steps in exploitation in the absence of legislation that applied strictly to petroleum operations. The enactment of modern legislation in many of these Republics encouraging and protect¬ing exploitations may cause tremendous oil activities in these countries, and the results may be comparable with the magnitude of the undertakings and the prestige of the companies now entering this territory.These, oil fields are admirably located for convenient distribution of petroleum by water to all the Nations using oil as fuel for shipping and industrial concerns. The oil markets of the western coast of South America will derive immense benefits from the Panama Canal. This navigation route brings these markets into direct ocean shipment with the Atlantic coasts of the Western and Eastern Hemispheres.One deterrent to oil production in the Republics of South America is the want of inland. transportation facilities, but the recent laws of these Republics without exception provide for acquiring rights of way for pipe lines and other modes of transportation; and doubtless the great interests and. syndicates already operating in these regions will, as production increases, provide ample pipe line transportation sufficient to convey to the coast the oil produced. It way be assumed, from the legal guarantees afforded, and from operating equipment and machinery that are now being concentrated that refineries will be erected at shipping points for the purpose of making these petroleum products accessible to the world."

May 1, 1921

By D. E. Ingersoll

This report describes the preparation characteristics of anthracite from the Mammoth and Holmes veins in Schuylkill County, Pa., as determined by the Federal Bureau of Mines laboratory separations at specific gravities of 1.50 to 1.90. The Holmes vein anthracite contains approximately 13 percent ash, and the Mammoth vein contains about 9 percent as fed to the breaker. Crushing Broken, Egg, and Stove sizes from each vein produces Pea-size anthracite of lower ash content than that contained in Buckwheat No.1 size and smaller. The Buck-wheat No.5 size has the highest ash content of all the sizes examined. Potential recovery from a mixture of the two veins as received at the breaker, separated at 1.90 specific gravity, is approximately 64 percent of the feed at 11.0 percent ash. The same materials separated at 1.80 specific gravity yield about 61 percent with an ash content of 10.1 percent. All rejects are from the Holmes vein, because the entire Mammoth material is less than 10.0 percent ash.

Jan 1, 1960

By C. A. Robotham

The following; paper describes underground mining practices of the Riverside Cement Co. of Los Angeles, Calif., in the Stanley limestone deposit at Crestmore, Riverside County, Calif. It is one of a series of papers being prepared for and published by the United States Bureau of Mines on mining methods and costs in tae various mining districts in the United States. ACKNOWLEDGMENTS Acknowledgment is made of the assistance received from E. D. Gardner, supervising engineer of the United States Bureau of Mines Experiment Station, Tucson, Ariz., in connection with the preparation of this paper and of the cooperation of John Treanor, president of the Riverside Cement Co. Valuable assistance in developing the mining methods was obtained from a study of similar practices in the copper-mining; districts of Ray and Globe-Miami, Ariz.

Jan 1, 1934

By W. P. Diamond

Coalbeds exhibit a directional permeability, with the maximum permeability oriented parallel to the face cleat. Thus, the most efficient pattern of vertical degasification holes for a coalbed is dependent upon cleat orientation. Surface joints, infrared photolinears, and Ronchi grating photolinears were investigated as potential estimators of subsurface cleat orientation. Cleat orientations were measured in 18 mines, in the Pittsburgh coalbed in southwestern Pennsylvania and northern West Virginia to be used as a standard against which prediction techniques would be evaluated. Two cleat systems with a strong geographic segregation were measured in the study area: N 670 W -N 280 E (950 separation) for the north, and N 76° W -N 17° E (930 separation) for the south. Directional data obtained from the three techniques investigated yielded satisfactory regional predictions of cleat orientation. Analysis of surface joints was the only technique considered sufficiently reliable on a local basis. Prediction of cleat orientation is based on the pairing of the principal directional sets into all reasonable combinations of fundamental systems. The system or systems composed of the most dominant sets nearest to 90° separation are likely to be a reliable prediction of cleat orientation. The most dominant set of the system selected is likely to be the face cleat.

Jan 1, 1976

By William H. Pomroy

Spontaneous combustion fires involving high-sulfide-content ores are a relatively infrequent yet serious safety hazard in mining. They are also the cause of lengthy mine shutdowns because they typically occur in areas of a mine where abundant fuel material is present but which are inaccessible for fire fighting. This Bureau of Mines report describes research to design, fabricate, and test in the laboratory and field a system that warns of spontaneous combustion fires in metal mines. Overall performance of the detection system was found to be satisfactory, in that the system was capable of reliably detecting low levels of combustion products believed to indicate the preflaming stage of spontaneous combustion in metal mines. Installation of similar systems in mines with a high risk of spontaneous combustion is recommended. Principal operating problems and recommended corrective actions are also discussed.

Jan 1, 1987

By D. Harrington

While apparently the hysteria with regard to silicosis and other occupational diseases has largely subsided and this subject is being more carefully considered and soberly judged, it would be poor policy for any employer to maintain that the storm has ended and that he can relax and revert to conditions as they were 5, 10, or more years ago. The fact is that the plan of paying occupational-disease compensation is now in its infancy and can be expected to grow rapidly. At present, while all of the States of the Union, including the District of Columbia and excepting only Arkansas and Mississippi, have compensation acts, only the following make provision for occupational diseases to some extent or in one way or another: California, Delaware, Connecticut, District of Columbia? Illinois, Indiana, Kentucky, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Jersey, New York, North Carolina, North Dakota, Ohio, Pennsylvania, Rhode Island, Washington, West Virginia, and Wisconsin. Silicosis is compensable in one way or another in California, Connecticut, District of Columbia, Illinois, Kentucky, Massachusetts, Missouri, New York, North Carolina, North Dakota, Ohio, Pennsylvania, West Virginia, and Wisconsin, and possibly in other States. During the past few months, occupational-disease legislation (largely silicosis) has been considered in some form in Arkansas, California, Delaware, Idaho, Maryland, Kansas, Massachusetts, Michigan, Minnesota, Montana, Nebraska, New Jersey, Ohio, Pennsylvania, Tennessee, Utah and Washington. It will be surprising if comparatively comprehensive occupational-disease legislation is not on the statute books of nearly every State in the Union within the next 5 years. With this situation confronting him, the farsighted industrialist who has the interest of his organization at heart, if he has not already done so will immediately start to "put his house in order" by studying possible occupational disease hazards to his employees and promptly applying known remedial measures or attempting to devise such measures if none exist. Unquestionably, one of the most important of the surveys to be made relates to dust occurrence, as State laws on occupational disease are almost certain to contain provisions, on silicosis and, with almost equal certainty, the provisions of any State law are not likely to be particularly similar to those of other States.

Jan 1, 1938

This Bureau of Mines report on underground mine communications addresses methods and equipment to meet the communication requirements of working sections and places of coal and metal-nonmetal mines. A review of the status of trapped miner detection is also presented.

Jan 1, 1977

By W. L. Cooley

The report provides a detailed analysis of 23 electrical accident countermeasures contemplated for use in the metal/non-metal mining industry. The costs and potential benefits of implementing groups of these countermeasures are estimated, and methods arc outlined by which the operator ran choose countermeasures in an effective manner. The analysis is based largely on an extensive electrical accident event tree which is developed in detail. For those countermeasures which are not currently technically feasible, several prototype devices were developed to help speed development. These included a trolley arc eliminator and a safer mine electricians multimeter.

Jan 1, 1982

By W. J. McConnell, C. P. Yaglaglou

"IntroductionThis paper on the kata thermometer is issued by the Bureau of Mines on account of the general interest in this instrument and the fact that it is frequently used in studies of mine ventilation conditions with regard to comfort and health of miners. It has been used in the studies being conducted along this line by the Bureau of Mines on the effects of high temperatures and humidities of air in mine working on the comfort conditions, as well as in studies of atmospheric conditions in mine, railway and vehicular tunnels.The study of the various physiological responses of the human body to different degrees of temperature combined with different percentages of relative humility in still and in moving air, now being conducted at the Pittsburgh experiment station of the bureau in the research laboratory of the American Society of Heating and Ventilating Engineers, cooperating with the Bureau of and the U. S. Public Health Service, presents an added opportunity of investigating the instruments that have been devised to measure atmospheric conditions as they affect the comfort and health of human beings.The ordinary mercury thermometer, as pointed out by Heberden3 almost hundred years ago is a very inadequate instrument for measuring the physiological effects of atmospheric conditions. It merely accounts for that part of the body heat lost by raliation and convection, while as a matter of fact greater part of the body heat resulting from the metabolic process within the body is eliminated by means of evaporation from the surface of the body."

Jan 1, 1924

By E. J. Gleim

In the mining of coal the trend is toward more and more mechanization. This increased use of machinery to replace hand labor is assuming many new forms and presents a constantly changing aspect. Safety engineers must be alert if the many electrical problems resulting from these new installations are to be handled safely. Some of these problems present possible electrical hazards that may be overlooked by the safety engineer unless they are called to his attention by one who has made a special study of the conditions. The foregoing is especially true of conveyor systems of mining. The terms "conveyor systems" and "conveyor mining" as used in this paper refer to those systems in which various types of conveyors are employed to transport coal away from the working place. In some mines this means complete elimination of track, cars, and locomotives. In others it means that conveyors take the coal from the working place to a convenient loading point, from which transportation is completed by cars and locomotives.

Jan 1, 1941

By J. G. Walters

In 1928, the Coal Carbonization Section of the Federal Bureau of Mines, in cooperation with the American Gas Association, began a survey of the carbonizing properties of American coals. A standard test method for evaluating the carbonizing properties of coals that met the following conditions was developed: To yield products similar to those obtained in commercial operations. To produce yields sufficient to permit analyses and tests of quality. To be laboratory size. To be convenient to operate. To permit reproducible control of test conditions and results. This test method has become known as the Bureau of Mines-American Gas Association (BM-AGA) test (53),3/ and more coals of greater variety have been tested in this apparatus than in any other of similar scale.

Jan 1, 1961

By Frank D. Lamb, D. A. Woodard

"INTRODUCTION The iron-ore deposits near Cranberry, N. C., were worked as early as 1820, and records show that to date at least 1,500,000 tons of ore has been mined.. The early operators depended on selective mining and hand cobbing to yield a product containing 40 to 50 percent iron. Later, a magnetic concentrator was erected by the Cranberry Furnace Co. and was operated periodically until 1930. The magnetic cobbing method employed yielded satisfactory concentrates, but the plant was shut down because costs were too high. 4/Early in 1944, in connection with the sponge-iron program of the Bureau of Mines, North Carolina and Tennessee were surveyed for the purpose of finding a readily available source of high-grade iron ore for use in the experimental production of sponge iron at Salisbury, N. C., and samples from various sources were tested in the laboratory. The Cranberry ore proved to be best with respect to grade of magnetite concentrates produced, and it was decided that a pilot mill should be built on the Cranberry mine property and that the concentrate made there should be shipped to Salisbury for direct-reduction tests in a commercial brick kiln."

Dec 1, 1946

By J. D. Kalasky, Stephen Krickovic

A degasification experiment was conducted in a Pocahontas No. 3 coalbed mine in Virginia. It involved (1) drilling holes in the coalbed in the out- side headings of a set of five being developed in virgin area, and (2) conducting a methane emission rate study as mining progressed and additional holes were drilled. Degasification from all drill holes except the longest in each of the outside headings and the first three drilled (excluding the in-situ pressure hole), was erratic and inconsequential in methane emission rates. The two longest holes liberated 66 and 79 cfm of methane, which is significant for the coalbed, but such quantity lasted a relatively short time; the first three were uniform but low in methane emission.

Jan 1, 1972

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions3 issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor; if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1968

By E. L. Rawlins

The Bureau of Mines, with the cooperation of the Natural Gas Association of America, has conducted a study of leakage losses from natural-gas transmission lines. This study has shorn that surveys to determine the leakage from transmission lines lead to line repair work that not only aids in the conservation of gas, but can be made to show financial returns of large magnitude.2 In order to conduct the study, it was necessary to develop accurate and reliable methods of determining the actual leakage from pipe lines. METHODS OF TESTING Three methods that were developed and used to determine the leakage losses from high-pressure natural-gas transmission lines are: (1) The "pressure-drop" method, (2) The "metering-in and metering-out" method. (3) The "metering-in" method.

Jan 1, 1926

By Ruth F. Brinkley

This circular summarizes the research and technologic activities and publications of the Federal Bureau of Mines Division of Explosives Technology4/ during fiscal year 1959 (July I) 1958-June 30, 1959). Part I briefly describes the programs that were active during the report period and presents a summary of some of the information not published elsewhere. In many instances the results are only preliminary and are subject to revision on the basis of continuing investigations. Detailed reports of all programs not security classified will be made later. Part II lists and describes briefly the publications of the Division during fiscal year 1959. If the published material has some bearing on activities still current during the report period, this is indicated by references in Part I.

Jan 1, 1961

By C. C. Furnas

Despite the fact that a great many industrial processes depend on efficient contact between a gas stream and a bed of broken solids for their operation, the data in the literature are very meager. Several investigations3 have been undertaken, but the work has been limited in scope and application. BUREAU OF MINES PROGRAM OF RESEARCH For the past 10 years the United States Bureau of Mines has been engaged in research with the object of formulating a more or less complete quantitative theory of the workings of the iron blast furnace. Obviously, in order to do this one of the essentials is to have considerable definite information on the laws of gas flow through beds of broken solids. This report in a brief summary of the experimental work on the problem which has been done at the North Central Experiment Station. The complete report with more detailed tabulation of the data and explanations of the experimental procedure is in process of publication in the form of a bulletin.

Jan 1, 1928