US3248169A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of regenerating sodium sulfite waste liquors
Assignee: —
•
Filing: —
•
Granted: 1966-04-26
•
Expires: 1983-04-26
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:07
CPC Classifications
D; D21; D21C; D21C11/00; D21C11/02; Y; Y10; Y10S; Y10S423/00; Y10S423/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
139 words
A METHOD OF TREATING SPENT SULFITE LIQUOR OBTAINED FROM COOKING CELLULOSE MATERIALS WITH A SULFITE COOKING LIQUOR WHICH COMPRISES THE STEPS OF: EVAPORATING WATER FROM SAID SPENT LIQUOR TO FORM A CONCENTRATING LIQUOR; BURNING THE CONCENTRATED LIQUOR IN A COMBUSTION FURNACE TO FORM A SULFUR DIOXIDE CONTAINING COMBUSTION GAS AND A SMELT CONTAINING SODIUM AND SULFUR; DISSOLVING THE SMELT TO OBTAIN A SOLUTION CONTAINING SODIUM SULFIDE AND SODIUM CARBONATE; PRECIPITATING THE SODIUM CARBONATE AND SEPARATING THE SODIUM CARABONATE FROM THE SOLUTION OF SODIUM SULFIDE; PASSING THE SULFIDE SULFUR CONTENT OF SAID SOLUTION TO THE COMBUSTION FURNACE WITHOUT APPRECIABLE REACTION OF SAID SULFUR CONTENT WITH THE SULFUR IN THE SPENT LIQUOR WHEREIN A PORTION OF THE SULFUR SO PASSED IS CONVERTED TO SULFUR DIOXIDE; AND ABSORBING THE SULFUR DIOXIDE SO PRODUCED IN A SOLUTION PREPARED FROM THE PRECIPITATED SODIUM CARBONATE.
Claim 2
Independent Claim
139 words
A METHOD OF TREATING SPENT SULFITE LIQUOR OBTAINED FROM COOKING CELLULOSE MATERIALS WITH A SULFITE COOKING LIQUOR WHICH COMPRISES THE STEPS OF: EVAPORATING WATER FROM SAID SPENT LIQUOR TO FORM A CONCENTRATING LIQUOR; BURNING THE CONCENTRATED LIQUOR IN A COMBUSTION FURNACE TO FORM A SULFUR DIOXIDE CONTAINING COMBUSTION GAS AND A SMELT CONTAINING SODIUM AND SULFUR; DISSOLVING THE SMELT TO OBTAIN A SOLUTION CONTAINING SODIUM SULFIDE AND SODIUM CARBONATE; PRECIPITATING THE SODIUM CARBONATE AND SEPARATING THE SODIUM CARABONATE FROM THE SOLUTION OF SODIUM SULFIDE; PASSING THE SULFIDE SULFUR CONTENT OF SAID SOLUTION TO THE COMBUSTION FURNACE WITHOUT APPRECIABLE REACTION OF SAID SULFUR CONTENT WITH THE SULFUR IN THE SPENT LIQUOR WHEREIN A PORTION OF THE SULFUR SO PASSED IS CONVERTED TO SULFUR DIOXIDE; AND ABSORBING THE SULFUR DIOXIDE SO PRODUCED IN A SOLUTION PREPARED FROM THE PRECIPITATED SODIUM CARBONATE.
References Cited (Backward Citations)
CA504057A
Cited
US1689534A
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US2320294A
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US2351780A
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US2730445A
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US2824071A
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US2849292A
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US2792350A
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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) | 1969-04-25 | 1969-10-25 | 1970-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-04-25 | 1973-10-25 | 1974-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-04-25 | 1977-10-25 | 1978-04-26 | $7700.00 | Window Closed / Lapsed |