Patent US3622443A successfully refreshed from Google Patents.
US3622443A
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Chemical recovery system for use in a pulping process
Assignee: OI Glass Inc
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Filing: 1970-03-04
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Granted: 1971-11-23
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Expires: 1990-03-04
Abstract
Abstract A method for the utilization and recovery of sodium and sulfur values used in pulping processes which method includes contacting a first portion of a bisulfite sulfite solution with the smelt product of the recovery furnace with a resultant solution after clarification that can be employed as a cooking liquor. The bisulfite sulfite solution is produced by scrubbing sulfur dioxide with a sodium carbonate solution having a molar concentration of from 0.1 to 1.0. The second portion of the bisulfite sulfite solution has a molar ratio of 4 to 1 and a pH of about 6.8 to 7.0 and is recycled and combined with the sodium carbonate scrubbing solution.
Inventors
- 👤 Sergio F Galeano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:01
CPC Classifications
C; C01; C01D; C01D5/00; C01D5/14; D; D21; D21C; D21C11/00; D21C11/06; Y; Y10; Y10S; Y10S423/00; Y10S423/03
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
137 words
A process for recovery of sodium and sulfur base cellulosic pulping chemicals in a spent pulping liquor wherein the process consists essentially of intimately contacting and simultaneously scrubbing a gas containing sulfur dioxide flowing at the rate of 2100 cubic feet a minute to 3300 cubic feet a minute with a 0.1 to 1 molar solution of sodium carbonate at a rate of 2 gallons per minute to 10 gallons per minute to produce a sodium bisulfite sodium sulfite solution with a molar ratio of 4 to 1 and a pH of 6.8 to 7.0 recycling a portion of said sodium bisulfite sodium sulfite solution to said contacting step and then contacting the other portion of said sodium bisulfite sodium sulfite solution with spent pulping liquor smelt to produce a pulping liquor suitable for pulping cellulosic materials.
References Cited (Backward Citations)
US1870944A
Cited
US3003908A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-22 | 1975-05-24 | 1975-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-22 | 1979-05-24 | 1979-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-22 | 1983-05-24 | 1983-11-23 | $7700.00 | Window Closed / Lapsed |