Patent US2922735A successfully refreshed from Google Patents.
US2922735A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing pulping liquor
Assignee: Texas Gulf Sulphur Co
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Filing: 1956-12-18
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Granted: 1960-01-26
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Expires: 1976-12-18
Abstract
No abstract record available.
Inventors
- 👤 Henry F Johnstone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:13
CPC Classifications
D; D21; D21C; D21C3/00; D21C3/04; D21C3/06; Y; Y10; Y10S; Y10S423/00; Y10S423/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
185 words
A PROCESS OF PRODUCING SULFITE COOKING LIQUOR FOR A PULPING OPERATION COMPRISING REMOVING SULFUR DIOXIDE FROM FLUE GAS BY SCRUBBING FLUE GAS WITH AN AQUEOUS AMMONIACAL SOLUTION, SEPARATING THE SCRUBBER EFFLUENT INTO A FIRST PORTION AND A SECOND PORTION, REMOVING INSOLUBLE IMPURITIES FROM SAID FIRST AND SECOND PORTIONS, CONVERTING THE AMMONIUM SULFITE IN SAID FIRST PORTION TO SOLID CALCIUM SULFITE PRECIPITATE BY REACTION WITH CALCIUM COMPOUND SELECTED FROM THE GROUP CONSISTING OF CALCIUM OXIDE, CALCIUM HYDROXIDE AND CALCIUM CARBONATE INTRODUCED THEREIN FILTERING THE SOLID CALCIUM SULFITE PRECIPITATE FROM THE REMAINING AMMONIACAL SOLUTION, RETURNING THE FILTRATE TO FLUE GAS SCRUBBING SOLUTION, REMOVING WATEWR SOLUBLE IMPURITIES FROM THE RETAINED CALCIUM SULFITE PRECIPITATE BY WASHING THE PRECIPITATE WITH WATER, THEREAFTER DISPERSING THE CALCIUM SULFITE IN WATER TO FORM AN AQUEOUS SLURRY, CONVERTING THE SLURRY TO COOKING LIQUOR BY CONTACT WITH GAS CONTAINING SULFUR DIOXIDE, ADDING SULFURIC ACID TO SAID SECOND PORTION OF SAID SCRUBBER EFFLUENT TO CONVERT AMMONIUM SULFITE CONTAINED THEREIN TO AMMONIUM SULFATE AND SULFUR DIOXIDE, STRIPPING SULFUR DIOXIDE FROM THE SOLUTION BY PASSING STEAM THROUGH SAID SOLUTION IN CONTACT THEREWITH, RECOVERING AMMONIUM SULFATE FROM THE RESIDUAL
Claim 2
Dependent Claim
185 words
A PROCESS OF PRODUCING SULFITE COOKING LIQUOR FOR A PULPING OPERATION COMPRISING REMOVING SULFUR DIOXIDE FROM FLUE GAS BY SCRUBBING FLUE GAS WITH AN AQUEOUS AMMONIACAL SOLUTION, SEPARATING THE SCRUBBER EFFLUENT INTO A FIRST PORTION AND A SECOND PORTION, REMOVING INSOLUBLE IMPURITIES FROM SAID FIRST AND SECOND PORTIONS, CONVERTING THE AMMONIUM SULFITE IN SAID FIRST PORTION TO SOLID CALCIUM SULFITE PRECIPITATE BY REACTION WITH CALCIUM COMPOUND SELECTED FROM THE GROUP CONSISTING OF CALCIUM OXIDE, CALCIUM HYDROXIDE AND CALCIUM CARBONATE INTRODUCED THEREIN FILTERING THE SOLID CALCIUM SULFITE PRECIPITATE FROM THE REMAINING AMMONIACAL SOLUTION, RETURNING THE FILTRATE TO FLUE GAS SCRUBBING SOLUTION, REMOVING WATEWR SOLUBLE IMPURITIES FROM THE RETAINED CALCIUM SULFITE PRECIPITATE BY WASHING THE PRECIPITATE WITH WATER, THEREAFTER DISPERSING THE CALCIUM SULFITE IN WATER TO FORM AN AQUEOUS SLURRY, CONVERTING THE SLURRY TO COOKING LIQUOR BY CONTACT WITH GAS CONTAINING SULFUR DIOXIDE, ADDING SULFURIC ACID TO SAID SECOND PORTION OF SAID SCRUBBER EFFLUENT TO CONVERT AMMONIUM SULFITE CONTAINED THEREIN TO AMMONIUM SULFATE AND SULFUR DIOXIDE, STRIPPING SULFUR DIOXIDE FROM THE SOLUTION BY PASSING STEAM THROUGH SAID SOLUTION IN CONTACT THEREWITH, RECOVERING AMMONIUM SULFATE FROM THE RESIDUAL
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) | 1963-01-25 | 1963-07-27 | 1964-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-25 | 1967-07-27 | 1968-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-25 | 1971-07-27 | 1972-01-26 | $7700.00 | Window Closed / Lapsed |