US3215587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous process and apparatus for delignification of cellulosic material
Assignee: Lummus Technology LLC
•
Filing: 1963-01-21
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Granted: 1965-11-02
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Expires: 1983-01-21
Abstract
No abstract record available.
Inventors
- 👤 Salvatore A Guerricri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:50
CPC Classifications
D; D21; D21C; D21C1/00; D21C1/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
A PROCESS FOR TREATING CELLULOSIC MATERIAL COMPRISING FORMING AN EXPANDED MASS OF CELLULOSIC MATERIAL, PREHEATING MATERIAL TO A TEMPERATURE SLIGHTLY BELOW THE BOILING POINT OF WATER IN A FIRST ZONE SO AS TO DRIVE OFF SURFACE MOISTURE FROM SAID MATERIAL, INTRODUCING THE PREHEATED MATERIAL INTO A SECOND HEATED SECOND ZONE, REMOVING PART OF THE AIR AND MOISTURE AND OCCLUDED GASES IN THE PORES OF THE MATERIAL AS OVERHEAD VAPORS, MAINTAINING THE MATERIAL IN AN EXPANDED MASS CONDITION WITHIN THE SECOND ZONE, AND VACUUM DEGASSING THE MATERIAL IN A THIRD ZONE TO SUBSTANTIALLY ALL MOISTURE AND GASES FROM SAID MATERIAL.
Claim 2
Dependent Claim
114 words
APPARATUS FOR TREATING CELLULOSIC MATERIAL, COMPRISING A PREHEATER INCLUDING HEATING MEANS AND GAS-FEEDING MEANS IN THE LOWER REGION OF SAID PREHEATER TO MAINTAIN THE MATERIAL IN AN EXPANDED MASS CONDITION, A DRIER RECEIVING PREHEATED MATERIAL FROM SAID PREHEATER AND INCLUDING HEATING MEANS TO DRIVE MOISTURE OUT OF SAID MATERIAL AS AN OVERHEAD VAPOR, MEANS TO FORM THE MATERIAL WITHIN SAID DRIER INTO AN EXPANDED MASS, SAID LAST MENTIONED MEANS INCLUDING MEANS TO RECYCLE A PORTION OF THE OVERHEAD VAPOR TO A LOWER REGION OF SAID DRIER, A VACUUM TANK FOR DEGASSING SAID MATERIAL TO REMOVE AIR AND MOISTURE FROM THE MATERIAL, AND MEANS TO INTRODUCE SAID MATERIAL FROM SAID DRIER INTO SAID VACUUM TANK.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-01 | 1969-05-03 | 1969-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-01 | 1973-05-03 | 1973-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-01 | 1977-05-03 | 1977-11-02 | $7700.00 | Window Closed / Lapsed |