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Results 251 - 260 of 260
The use of a partially slotted 6.5-Inch-inside-diameter vertical pipe to remove methane from a longwall gob area at a depth of 2,260 feet in the Pocahontas No. 3 Coalbed was investigated. The value of gas removed by such a pipe under free-flow condition...
Methane-flow and pressure data taken from a mine in the Pocahontas No. 3 Coalbed are compared with flow rates from lump coal obtained in laboratory experiments. From this, it is concluded that the main source of gas is the intact coalbed rather than a "...
Methane Emission Rate Study in a Deep Pocahontas No. 3 Coalbed Mine in Conjunction With Drilling Degasification Holes in the CoalbedA degasification experiment was conducted in a Pocahontas No. 3 Coalbed mine in Virginia. It involved (1) drilling holes in the coalbed in the outside headings of a set of five being developed in virgin area and (2) conducting a methane emission rate st...
The method of moving averages was found useful in assessing the nature of methane emission in coal mines. Emission rates were influenced markedly by the presence of abandoned oil and gas wells in the vicinity of the mine. Such wells appeared to increase...
The Methane Migration and Storage Characteristics of the Pittsburgh, Pocahontas No. 3, and Oklahoma Hartshorne CoalbedsMethane flows and pressures were measured in mines in the Pittsburgh, Hartshorne, and Pocahontas No. 3 Coalbeds. From the data, the permeability of each of these coalbeds was computed.
1/1/1971 - Reports of InvestigationsThe purpose of this study was to determine the characteristics of methane emissions during coal extraction by a longwall mining system. The study was conducted over 22 consecutive shifts. The average methane emission rate from the Lower Kittanning coalb...
8/1/1970 - Technical Progress ReportsMethane emission rates were studied in a Pittsburgh coalbed mine in northern West Virginia. Air volumes and methane percentages were recorded, and time studies of the miner were made during five consecutive operating days, during which a complete cycle...
3/1/1969 - Technical Progress ReportsThe Bureau of Mines has conducted desorption work on fine coal particles at near atmospheric pressure. An apparatus has been developed that uses a capacitance manometer to measure desorption of methane from coal particles up to 2 inches in diameter and ...
1/1/1963 - Reports of InvestigationsTests were conducted in the Pocahontas No. 4 coalbed in southern West Virginia to determine if successful degasification techniques, developed during an earlier study in the Pittsburgh coalbed, would effectively remove methane from those usually more ga...
1/1/1962 - Reports of InvestigationsA 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 ...