Results 101 to 110 of about 16,144,632 (222)
Methane and dust controls for longwalls : Pocahontas no.3 coalbed, Grundy, Virginia [PDF]
"The periphery of longwall panels in the Pocahontas No. 3 Coalbed is characterized by a zone of reduced permeability that inhibits the natural drainage of methane. A residual gas pressure of 105 psig was measured after 1 year in an isolated block of coal
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Removing methane (degasification) from the Pocahontas No. 4 coalbed in southern West Virginia [PDF]
"Tests 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 be effective in removing methane from those usually ...
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Methane control by isolation of a major coal panel : Pittsburgh coalbed [PDF]
"As one of its projects for degasification of major panels of coal prior to mining within them, the Bureau of Mines conducted methane emission studies during development of a set of three headings 1,800 feet in a major coal panel (2,700 by 3,500 feet ...
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Design of nonlinear sliding mode controller for hydraulic fracturing of coalbed methane
, 2016 For coordination and synchronous control problem of multi motors of water pump for hydraulic fracturing in coalbed methane exploit process, a method of nonlinear sliding mode control was proposed, design method of nonlinear sliding mode controller for ...
LI Feng, MA Tiehua, YAO Shuncai
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Removing methane (degasification) from the Pittsburgh coalbed in northern West Virginia [PDF]
"Tests 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 be effective in removing methane from those usually ...
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Analysis of Nozzle Flow under Low Pressure Non-Critical Flow in Coalbed Methane Well
Shiyou jixie, 2020 The law of nozzle flow is of great significance for establishing the law of reservoir and wellbore pressure and gas well production. In view of this, according to the theoretical calculation model of the on-site nozzle, the theoretical calculation model ...
He Dong +4 more
doaj
The composition of coalbed gas [PDF]
"Samples of gas were obtained directly from the coalbed during drilling of horizontal and vertical boreholes in six different formations. The samples were analyzed by gas chromatography for C1 to C5 hydrocarbons and for 02, N2, H2, He, and CO2.
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Methane emissions from an advancing coal mine section in the Pittsburgh coalbed [PDF]
"The methane emissions from an advancing coal mine section were continuously monitored for 120 days. During this time, the section advanced 2,000 feet into virgin Pittsburgh coalbed producing 54,565 tons of coal with a total methane emission of 91 ...
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Meikuang AnquanIn the area with complex hydrogeological conditions, the water abundance of surrounding rock and the amount of replenishment to the coal seam is of an important impact on the propagation speed of pressure in the coal seam during drainage, and are the key
Yafei ZHANG +4 more
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Stage Difference Analysis of Well Shutdown Failures in Coalbed Methane Horizontal Wells
ProcessesTo identify the main controlling factors of well shutdowns in different production stages of coalbed methane (CBM) horizontal wells, this study investigated the production parameters and pump inspection records of 25 horizontal wells in Huabei Oilfield. This paper first summarizes the types, causes, and impact degrees of well shutdown faults.
Liping Zhao +7 more
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