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US3034580A Expired / Lapsed US ⏱️ 0.0 years remaining

In situ combustion of lignite

Assignee: Phillips Petroleum Co
•
Filing: 1959-08-31
•
Granted: 1962-05-15
•
Expires: 1979-08-31
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Abstract

No abstract record available.

Inventors

  • 👤 Frederick E Frey
  • 👤 Francis W Crawford
  • 👤 John W Marx

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 15:01
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24; E21B43/243

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 120 words
A PROCESS FOR PRODUCING FUEL GASED AND LIQUIDS FROM A LIGNITE STRATUM CONTAINING AT LEAST 10 WEIGHT PERCENT OXYGEN AUTOGENOUS IN SITU COMBUSTION WHICH COMPRISES PROVIDING A WALL EXTENDING FROM GROUND LEVEL INTO SAID STRATUM AND A TUBING STRING IN SAID WELL FORMING AN ANNULUS WITH THE WALL OF SAID WELL; IGNITE THE LIGNITE ADJACENT SAID WELL BY HEATING SAME TO IGNITION TEMPERATURE AND INJECTING COMBUSTION-SUPPORTING GAS THRU ONE OF SAID ANNULUS AND SAID TUBING SO AS TO CONTACT THE HEATED LIGNITED WITH SAID GAS AND ESTABLISH A COMBUSTION ZONE, IN SAID LIGNITE; AFTER INGINITION IS EFFECTED, TERMINATING THE FLOW OF SAID GAS AND SUBMITTING THEREFOR AN O2-FREE FLUSHING GAS TO REMOVE FROM SAID WELL FLUIDS PRODUCE BY THE COMBUSTION.

References Cited (Backward Citations)

US2786660A Cited
US2584605A Cited
US2780449A Cited
US2761512A Cited
US2917112A Cited
US2952450A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1965-05-14 1965-11-13 1966-05-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1969-05-14 1969-11-13 1970-05-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1973-05-14 1973-11-13 1974-05-15 $7700.00 Window Closed / Lapsed

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