- Diseases and injuries
- Equipment, tools, and parts
- Geographic regions
- Geologic conditions and events
- Hazard prevention and control
- Hazards and exposures
- Mine locations, excavations, and structures
- Mining types and methods
- Population groups
- Products and materials
- Research disciplines
- Research methods and measures
- Tasks and activities
- Document types
Results 241 - 250 of 260
1/1/1974 - Information CircularsThis Bureau of Mines survey of methane emissions indicates that total daily emissions have declined from 227 mm ft3 in 1971 to 214.7 mm ft3 in 1973. The highest average daily emissions in million cubic feet per day are detailed by state.
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) wh...
Geologic Factors Causing Roof Instability and Methane Emission Problems: The Lower Kittanning Coalbed, Cambria County, PaA geologic study of Mines 32 and 33 in Cambria County, Pennsylvania, was conducted as part of a methane control research program.
The applicability of the "direct method" for determining the methane content of virgin coalbeds was tested. Preliminary results indicate that the direct method, when applied to exploration cores, can be successfully used to estimate coalbed gas content ...
To determine if coals from mines which had no history of detectable gas emission contained adsorbed methane, samples of coal at the shaft bottom and at an active face were obtained and placed in sealed metal cylinders.
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.
7/1/1972 - Technical Progress ReportsAn oil well penetrating the Pittsburgh bituminous coalbed in northern West Virginia was plugged and safely mined through 3 months later. Effectiveness of the plugging in preventing reservoir gas from entering the mine through the well hole was verified ...
Methane Diffusion Parameters for Sized Coal Particles: A Measuring Apparatus and Some Preliminary Results1/1/1972 - Reports of InvestigationsA sorption apparatus for measuring the equilibrium sorption isotherm and the rate of diffusion of methane from fine-sized coal was designed and constructed. Preliminary work that used Pittsburgh and Pocahontas No. 3 Coal shows that the diffusion coeffic...
1/1/1972 - Information CircularsThis survey was conducted to determine the magnitude of the methane emission and control problem in U.S. bituminous coal mines. The resultant data indicate that the emission rate for any given coalbed depends primarily on the coal production rate and on...
1/1/1972 - Reports of InvestigationsThe effect of water infusion on the flow of methane and on the production of dust was investigated at an active face in the Pittsburgh coalbed. The average total flow of methane at the face decreased by approximately 79 percent, whereas the flow from th...