US2774666A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of cooking liquor from spent soda pulping liquors
Assignee: STWB Inc
•
Filing: 1954-06-24
•
Granted: 1956-12-18
•
Expires: 1974-06-24
Abstract
No abstract record available.
Inventors
- 👤 Daniel M Barton
- 👤 Eugene W Schoeffel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:17
CPC Classifications
D; D21; D21C; D21C11/00; D21C11/04; Y; Y02; Y02P; Y02P40/00; Y02P40/40
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
116 words
A PROCESS FOR THE RECOVERY OF SODA BASE COOKING LIQUOR WHICH COMPRISES: DIGESTING WOOD CHIPS WITH SODA BASE COOKING LIQUOR; SEPARATING A WASTE SODA LIQUOR AND OXIDIZING, IN THE LIQUID PHASE, THIS LIQUOR AT A TEMPERATURE OF BETWEEN 150 AND 372 DEGREES CENTIGRADE AND AT LEAST 400 POUNDS PER SQUARE INCH PRESSURE WITH AT LEAST SUFFICIENT OXYGEN TO CONVERT ALL THE CARBON TO CARBON DIOXIDE AND ALL THE HYDROGEN TO STEAM; TREATING THE LIQUID EFFLUENT CONTAINING SODIUM CARBONATE AND BISCARBONATE WITH SUFFICIENT ALKALINE EARTH HYDROXIDE TO CAUSE PRECIPITATION OF SUBSTANTIALLY ALL OF THE CARBONATES AND BICARBONATES; SEPARATING THE PRECIPITATED ALKALINE EARTH CARBONATES; AND, RECYCLING THE FILTRATE CONTAINING SODIUM HYDROXIDE TO TREAT SUBSEQUENT BATCHES OF WOOD CHIPS.
Claim 2
Dependent Claim
116 words
A PROCESS FOR THE RECOVERY OF SODA BASE COOKING LIQUOR WHICH COMPRISES: DIGESTING WOOD CHIPS WITH SODA BASE COOKING LIQUOR; SEPARATING A WASTE SODA LIQUOR AND OXIDIZING, IN THE LIQUID PHASE, THIS LIQUOR AT A TEMPERATURE OF BETWEEN 150 AND 372 DEGREES CENTIGRADE AND AT LEAST 400 POUNDS PER SQUARE INCH PRESSURE WITH AT LEAST SUFFICIENT OXYGEN TO CONVERT ALL THE CARBON TO CARBON DIOXIDE AND ALL THE HYDROGEN TO STEAM; TREATING THE LIQUID EFFLUENT CONTAINING SODIUM CARBONATE AND BISCARBONATE WITH SUFFICIENT ALKALINE EARTH HYDROXIDE TO CAUSE PRECIPITATION OF SUBSTANTIALLY ALL OF THE CARBONATES AND BICARBONATES; SEPARATING THE PRECIPITATED ALKALINE EARTH CARBONATES; AND, RECYCLING THE FILTRATE CONTAINING SODIUM HYDROXIDE TO TREAT SUBSEQUENT BATCHES OF WOOD CHIPS.
References Cited (Backward Citations)
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Cited
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Cited
US1795557A
Cited
US2429143A
Cited
US2516827A
Cited
US2686120A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-12-18 | 1960-06-18 | 1960-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-12-18 | 1964-06-18 | 1964-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-12-18 | 1968-06-18 | 1968-12-18 | $7700.00 | Window Closed / Lapsed |