Postburn evaluation of the Hanna IV A and B UCG (underground coal gasification) experiments, Wyoming

Technical Report · Sun Jun 01 04:00:00 EDT 1986

OSTI ID:6829673

Oliver, R L; Sinks, D J; Berdan, G

Data from process monitoring, geophysical surveys, and postburn core studies were integrated to delineate the extent of affected coal and overburden at the Hanna IV A and B underground coal gasification experiment sites in southeastern Wyoming. The experiments were conducted from December 1977 to September 1979 in the Hanna No. 1 coal bed of the Eocene Hanna Formation. A postburn coring and well logging program was initiated in the fall of 1983. Well locations were selected using cavity boundary predictions determined by process monitor wells, a high-resolution seismic survey (June 1983). Detailed coal and overburden core studies were completed, including petrographic and scanning electron microscopy, X-ray analyses, strength tests, maceral analyses, vitrinite reflectance, fluorescence analyses, and proximate analyses. The Hanna IV A and B experiments apparently produced two distinct, temperature-stratified cavities separated by a fault zone of minor total displacement. Maximum coal consumption occurred near the west end of the IV A pattern, producing an asymmetrical cavity. Overburden collapse reached 45 ft. (14 m) above the top of the coal seam. Zones of maximum roof collapse are commonly bounded by minor faults that act as planes of weakness along which overburden fails. Override was a significant problem at the IV B pattern, primarily caused by faulting. A high percentage of calcite cement and sufficient porosity in the overburden contributed to limited roof collapse away from the faults. High-temperature mineral assemblages and fluorescence spectral parameters indicate that burn temperatures exceeded 2191/sup 0/F (1200/sup 0/C). The zone of reaction apparently is narrow (approx.6 in. (0.15 m)). 41 refs., 28 figs., 6 tabs.

• Research Organization: Western Research Inst., Laramie, WY (USA)
• DOE Contract Number: FC21-83FE60177
• OSTI ID: 6829673
• Report Number(s): DOE/FE/60177-2289; ON: DE87006392
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
& Peat-- Gasification
010600 -- Coal
Lignite
& Peat-- Properties & Composition
BOREHOLE LINKING
CAVITIES
COAL DEPOSITS
COAL GASIFICATION
COAL SEAMS
DATA
DIMENSIONS
DRILL CORES
ELECTRICAL SURVEYS
ELECTROMAGNETIC SURVEYS
ELECTRON MICROSCOPY
EVALUATION
EXPERIMENTAL DATA
FEDERAL REGION VIII
FIELD TESTS
FLUORESCENCE
GASIFICATION
GEOLOGIC DEPOSITS
GEOPHYSICAL SURVEYS
IN-SITU GASIFICATION
IN-SITU PROCESSING
INFORMATION
LUMINESCENCE
MACERALS
MAGNETOTELLURIC SURVEYS
MICROSCOPY
MINERAL RESOURCES
NORTH AMERICA
NUMERICAL DATA
OPTICAL PROPERTIES
OVERBURDEN
PETROGRAPHY
PHYSICAL PROPERTIES
PROCESSING
REFLECTIVITY
RESOURCES
ROOFS
SCANNING ELECTRON MICROSCOPY
SEISMIC SURVEYS
SURFACE PROPERTIES
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TESTING
THERMOCHEMICAL PROCESSES
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USA
VERY HIGH TEMPERATURE
WELL LOGGING
WYOMING