The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 28, 1976
Filed:
Jan. 22, 1976
Applicant:
Inventors:
Robert E Pennington, Baytown, TX (US);
Michael A Gibson, Houston, TX (US);
George T Arnold, Baytown, TX (US);
Assignee:
Exxon Research and Engineering Company, Linden, NJ (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B / ; E21B / ;
U.S. Cl.
CPC ...
166259 ; 48DI / ; 166260 ; 166261 ; 166263 ; 166266 ;
Abstract
Coal liquids and gases are recovered from a thick underground coal seam by drilling one or more boreholes from the earth's surface into the lower part of the seam, burning out the coal over a limited area near the bottom of the seam, collapsing the overlying coal to form a rubblized zone extending vertically to a point near the upper boundary of the seam, driving a flame front vertically through the rubblized zone to liberate hydrocarbon liquids and produce gases, and recovering the liquids and gases from the rubblized zone.
Published as:
US3999607A; BE849005A; DE2652213A1; FR2338987A1; ZA766355B; AU1868976A; CA1056302A; GB1558381A; FR2338987B1;