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Results 201 - 210 of 259
1/1/1982 - Reports of InvestigationsThe Bureau of Mines has developed several techniques for draining methane from coalbeds in advance of mining. Drilling long horizontal holes from an underground location is one such technique, which was successfully demonstrated in the Pittsburgh and Su...
The Bureau of Mines investigated coal storage silos to determine how gassy coal must be for methane accumulations in a silo to become hazardous and where such accumulations are likely to occur. Methane concentrations were measured in the open space abov...
The Bureau of Mines has completed an underground degasification project in which an underground piping system was used to transport methane from the coalbed to the surface. In a 10-month period four horizontal holes were drilled to an average depth of 1...
Describes a simple, inexpensive test to measure the methane content of coal samples obtained from exploration cores. The results of tests are summarized in tabular form. These results include data on the gas content of 125 coalbeds in 15 states.
The face ventilation measurement method developed by the Bureau of Mines involves releasing a small volume of tracer gas (SF6) on the off-curtain side of the working face at the start of the mining cycle.
The Bureau of Mines has designed and put into operation a fail-safe control system for use in underground coal mines equipped with methane drainage pipelines. This control system can detect certain unsafe conditions and respond by automatically shutting...
The use of vertical surface degasification boreholes with bleeder systems and the use of a timbered bleeder system to degasify gob areas were studied by the Bureau of Mines. This report describes three gob degasification studies conducted in the Pittsbu...
1/1/1980 - Information CircularsReviews underground methane drainage programs being conducted in various coalbeds. Equipment used in drainage programs such as drills, underground pipelines, and methane monitoring systems is described.
Drainage of Methane From the Overlying Pocahontas No. 4 Coalbed From Workings in the Pocahontas No. 3 Coalbed1/1/1979 - Reports of InvestigationsThe Bureau of Mines conducted an experimental degasification project in Island Creek Coal Company Virginia Pocahontas No. 5 Mine. Methane from the overlying Pocahontas No. 4 Coalbed was entering mine workings in the Pocahontas No. 3 Coalbed through frac...
1/1/1979 - Reports of InvestigationsThe Bureau of Mines developed data on the methane content of the Hartshorne coalbed, Haskell and Le Flore Counties, Oklahoma. The methane content is calculated to be between 1.1 and 1.5 trillion cubic feet. Methane increases with depth, but the rate of ...