Method for recovery of coal energy

Patent · Tue Dec 21 04:00:00 EST 1971

OSTI ID:6051315

Glass, E D; Rhoades, V W

Two or more wells are drilled into a coal seam. Each well is completed to isolate all other strata from the coal seam. A radial horizontally directed fracture is induced so as to connect the wells communicatively. The coal seam is ignited through at least one injection well and the combustion front propagated from one or more injection wells through the horizontal fractures to subsequent production wells by injection of a combustion supporting gas. Injection pressures utilized are sufficiently high to raise the overburden at the fractured surfaces and permit continued air injection during the combustion process. Regulation of the width of the fracture network and corresponding gas and liquid flow is achieved by the control of the injection pressure. The continued production of a flammable gas and coal tar liquids is thereby afforded. (9 claims)

• Assignee: Cities Service Oil Co.
• Patent Number(s): US 3628929
• OSTI ID: 6051315
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
& Peat-- Gasification
CHEMICAL REACTIONS
COAL DEPOSITS
COAL GASIFICATION
COAL SEAMS
COAL TAR
COMBUSTION
ENHANCED RECOVERY
GASIFICATION
GEOLOGIC DEPOSITS
IN-SITU COMBUSTION
IN-SITU GASIFICATION
IN-SITU PROCESSING
INJECTION WELLS
MINERAL RESOURCES
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXIDATION
PROCESSING
RECOVERY
RESOURCES
TAR
THERMAL RECOVERY
THERMOCHEMICAL PROCESSES
WELLS