US2923535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Situ recovery from carbonaceous deposits
Assignee: Svenska Skifferolje AB
•
Filing: 1955-02-11
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Granted: 1960-02-02
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Expires: 1975-02-11
Abstract
No abstract record available.
Inventors
- 👤 Ljungstrom Fredrik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:43
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24; E21B43/243; E21B43/2401; E21B43/30
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
THE METHOD OF TREATING IN SITU A SUBTERRANEOUS STRATUM OF CARBONACEOUS MATERAL OF ESSENTIALLY SOLID CHARACTER AND RELATIVELY IMPERMEABLE TO FLOW OF GAS THERETHROUGH WHICH INCLUDES THE STEPS OF PREHEATING ELECTRICALLY A LOCALIZED GAS IMPERMEABLE PORTION OF SAID STRATUM AT A TEMPERATURE OF FROM ABOUT 100*C. TO A TEMPERATURE BELOW THAT OF SUBSTANTIAL OIL VAPORIZATION WHILE CONTROLLING THE PRESSURE IN SAID PREHEATED PORTION WHEREBY GASES ARE PRO-
Claim 2
Independent Claim
67 words
THE METHOD OF TREATING IN SITU A SUBTERRANEOUS STRATUM OF CARBONACEOUS MATERAL OF ESSENTIALLY SOLID CHARACTER AND RELATIVELY IMPERMEABLE TO FLOW OF GAS THERETHROUGH WHICH INCLUDES THE STEPS OF PREHEATING ELECTRICALLY A LOCALIZED GAS IMPERMEABLE PORTION OF SAID STRATUM AT A TEMPERATURE OF FROM ABOUT 100*C. TO A TEMPERATURE BELOW THAT OF SUBSTANTIAL OIL VAPORIZATION WHILE CONTROLLING THE PRESSURE IN SAID PREHEATED PORTION WHEREBY GASES ARE PRO-
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-02-01 | 1963-08-03 | 1964-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-02-01 | 1967-08-03 | 1968-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-02-01 | 1971-08-03 | 1972-02-02 | $7700.00 | Window Closed / Lapsed |