US3303088A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous liquid-phase rapid pulping
Assignee: Lummus Technology LLC
•
Filing: 1963-04-19
•
Granted: 1967-02-07
•
Expires: 1983-04-19
Abstract
No abstract record available.
Inventors
- 👤 Adolf W Gessner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:09
CPC Classifications
D; D21; D21C; D21C3/00; D21C3/22; D21C3/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
127 words
A PROCESS FOR PREPARING PULP BY THE CONTINUOUS DELIGNIFICATION OF CELLULOSIC MATERIAL AT SUPERATMOSPHERIC PRESSURE IN A DIGESTER HAVING AN IMPREGNATION ZONE, A DELIGNIFICATION ZONE AND A COOLING ZONE, WHICH COMPRISES: INTRODUCING A PREHEATED SLURRY OF CELLULOSIC MATERIAL AND COOKING LIQUOR INTO THE UPPER PORTION OF SAID DIGESTER; RAPIDLY HEATING SAID SLURRY TO A TEMPERATURE OF FROM ABOUT 240*F. TO ABOUT 280*F.; EFFECTING IMPREGNATION OF SAID CELLULOSIC MATERIAL IN SAID IMPREGNATION ZONE OF SAID DIGESTER; RAPIDLY HEATING SAID IMPREGNATED MATERIAL TO A TEMPERATURE OF FROM ABOUT 330*F. TO ABOUT 385*F.; EFFECTING DELIGINIFICATION OF SAID CELLULOSIC MATERIAL IN SAID DELIGNIFICATION ZONE OF SAID DIGESTER; COOLING SAID DELIGNIFIED A COOLING ZONE COMPRISED OF AT LEAST TWO SUB-STAGES IN SAID DIGESTER; AND WITHDRAWING SAID DILIGNIFIED MATERIAL FROM SAID DIGESTION ZONE.
Claim 2
Dependent Claim
127 words
A PROCESS FOR PREPARING PULP BY THE CONTINUOUS DELIGNIFICATION OF CELLULOSIC MATERIAL AT SUPERATMOSPHERIC PRESSURE IN A DIGESTER HAVING AN IMPREGNATION ZONE, A DELIGNIFICATION ZONE AND A COOLING ZONE, WHICH COMPRISES: INTRODUCING A PREHEATED SLURRY OF CELLULOSIC MATERIAL AND COOKING LIQUOR INTO THE UPPER PORTION OF SAID DIGESTER; RAPIDLY HEATING SAID SLURRY TO A TEMPERATURE OF FROM ABOUT 240*F. TO ABOUT 280*F.; EFFECTING IMPREGNATION OF SAID CELLULOSIC MATERIAL IN SAID IMPREGNATION ZONE OF SAID DIGESTER; RAPIDLY HEATING SAID IMPREGNATED MATERIAL TO A TEMPERATURE OF FROM ABOUT 330*F. TO ABOUT 385*F.; EFFECTING DELIGINIFICATION OF SAID CELLULOSIC MATERIAL IN SAID DELIGNIFICATION ZONE OF SAID DIGESTER; COOLING SAID DELIGNIFIED A COOLING ZONE COMPRISED OF AT LEAST TWO SUB-STAGES IN SAID DIGESTER; AND WITHDRAWING SAID DILIGNIFIED MATERIAL FROM SAID DIGESTION ZONE.
References Cited (Backward Citations)
US3097987A
Cited
US3200032A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-02-06 | 1970-08-08 | 1971-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-02-06 | 1974-08-08 | 1975-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-02-06 | 1978-08-08 | 1979-02-07 | $7700.00 | Window Closed / Lapsed |