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Results 51 - 60 of 85
1/1/1978 - Reports of InvestigationsThe Bureau of Mines investigated factors that influence the formation of methane and other hydrocarbon gases in coal, which is an integral part of the coalification process.
1/1/1978 - Reports of InvestigationsThe Bureau of Mines investigated the presence and extent of methane accumulations in mine roof cavities using a full-scale mine model. Methane was released at a constant rate into the roof of a cavity built onto a 700-ft wind tunnel.
The Bureau of Mines estimated the methane content of a coal, which depends primarily upon rank and pressure, from the adsorption equation V = kPn, where k and n are constants related to rank.
The Bureau of Mines made laboratory absorption measurements on oil shale samples, which showed that the amount of methane absorbed is proportional to pressure and oil yield, and can be much larger than would be predicted based solely on porosity. Oil sh...
The Upper Freeport coalbed was studied in Fayette County, Pennsylvania. This coalbed lies about 650 feet below the Pittsburgh coalbed and contains the largest remaining reserves of any coalbed in the county.
The Beckley Mine is one of five new mines in a heretofore unmined portion of the Beckley coalbed. The remoteness of these new mines from prior mining and their greater overburden preclude applying methane emission experience obtained in the old mines. F...
The Bureau of Mines evaluated the hydraulic stimulation of a gob degasification borehole to determine if this procedure would aid in degasifying a longwall panel.
Two degasification test boreholes were drilled to depths of 1,238 and 1,212 feet on Bureau of Mines property at Bruceton, Pennsylvania, as part of the Bureau of Mines long-range coal degasification program.
1/1/1976 - Reports of InvestigationsThis report describes three coal mine ventilation studies by the Bureau of Mines in which sulfur hexafluoride (SF6) was used as a tracer gas.
Methane Gas Content of the Mary Lee Group of Coalbeds, Jefferson, Tuscaloosa, and Walker Counties, Ala.1/1/1976 - Reports of InvestigationsIt is estimated that more than 1 trillion cubic feet of methane is contained within the coals of the Mary Lee Group in Jefferson, eastern Tuscaloosa, and southern Walker Counties, Alabama. It is calculated that approximately 90 pct of the methane is at ...