Methane drainage with cross-measure boreholes on a retreat longwall face

Conference · Sat Oct 01 04:00:00 EDT 1983 · Prepr., Soc. Min. Eng. AIME; (United States)

OSTI ID:6399542

Thakur, P D; Cervik, J; Lauer, S D

Methane drainage by cross-measure boreholes on retreat longwall faces can be a viable alternative to the vertical gob degas boreholes under favorable circumstances. The research was done in a mine working Pittsburgh Coal seam in Northern West Virginia under U.S.B.M. Co-operative Agreement No. 14-09-0050-3252. The study was the first application of this technique to Pittsburgh coal seam. A total of fourteen, small diameter, inclined boreholes were drilled over a retreat longwall panel from gate roads, to intersect the overlying coal seams. All boreholes were manifolded to a pipeline and the gob gas was extracted by an exhaust fan on surface. The methane capture ratio was poor at 7 to 18% at various stages of the longwall panel. A vertical gob degas borehole captured an additional 20% gas. Poor results were due to premature failures of the cross-measure boreholes leading to air leakage. For better performance the boreholes should be drilled from a point 30 to 45 m from longwall pillar over the largest chain pillar, the standpipe should be grouted for at least 6 m, and the entry containing boreholes and the pipeline must be supported to ensure access for maintenance, and optimization of methane capture. Coursing the ventilation air around longwall such that it forces methane-migration towards cross-measure boreholes can further improve methane capture. The optimum vertical inclination is 45/sup 0/ + or - 10/sup 0/.

• Research Organization: Conoco Inc., Morgantown, WV
• OSTI ID: 6399542
• Report Number(s): CONF-831009-
• Conference Information: Journal Name: Prepr., Soc. Min. Eng. AIME; (United States) Journal Volume: 83-398
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010900* -- Coal
Lignite
& Peat-- Environmental Aspects
012000 -- Coal
Lignite
& Peat-- Mining
AIR POLLUTION CONTROL
AIR QUALITY
ALKANES
BLOWERS
BOREHOLES
CAVITIES
COAL DEPOSITS
COAL SEAMS
CONTROL
DEGASSING
DIRECTIONAL DRILLING
DRILLING
ENVIRONMENTAL QUALITY
FEDERAL REGION III
FLUID FLOW
GAS FLOW
GEOLOGIC DEPOSITS
HYDROCARBONS
INCLINATION
LONGWALL MINING
METHANE
MINERAL RESOURCES
MINING
NORTH AMERICA
OPTIMIZATION
ORGANIC COMPOUNDS
PIPELINES
POLLUTION CONTROL
REMOVAL
RESEARCH PROGRAMS
RESOURCES
UNDERGROUND MINING
USA
WEST VIRGINIA