Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

NIOSHTIC-2 Publications Search

Search Results

Degasification of virgin Pittsburgh coalbed through a large borehole.

Authors
Fields-HH; Krickovic-S; Sainato-A; Zabetakis-MG
Source
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 7800, 1973 Jan; :1-27
NIOSHTIC No.
10000671
Abstract
The Bureau of Mines is in the process of degasifying a virgin area in northern West Virginia from the base of an 839-foot-deep vertical borehole. An in situ gas pressure hole 199 feet long, and seven degasification holes ranging in depth from 500 to 850 feet (average 618 feet) were drilled in an 8-foot-thick virgin Pittsburgh coalbed from the enlarged (14-foot diameter) bottom of this borehole. The in situ pressure at the back end of the hole and the range of gas and water flows from degasification holes as they were completed and closed off were 203 psi, 79,000 to 257,000 cfd (average 160,000 cfd), and 5 to 8 gpm per hole (average 6.8 Gpm), respectively. Twenty-four hours after the seven holes were connected through individual water traps to a common collector for natural venting of the gas through pipes to the atmosphere, the total gas and water flows and the in situ pressure dropped, respectively, to 971,000 cfd, 1.3 Gpm, and 18 psi. Eighty days later the corresponding values dropped to 529,000 cfd, 0.50 Gpm, and 13 psi. After 180 days of degasification, 91 million cubic feet of gas had been removed from the affected virgin area. This represents 60 to 70 percent of the gas calculated to be contained in the area of coal affected by the holes.
Keywords
Mine-gases; Mining-industry; Methanes; Methane-drainage; Methane-control; Explosive-gases; Explosive-atmospheres; Underground-mining; Coal-mining; Control-technology; Engineering-controls
CAS No.
74-82-8
Publication Date
19730101
Document Type
IH; Report of Investigations
Fiscal Year
1973
NTIS Accession No.
PB-224570
NTIS Price
A03
Identifying No.
RI-7800
NIOSH Division
PRC
Source Name
Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 7800
State
PA; WV
TOP