Patent US4181506A successfully refreshed from Google Patents.
US4181506A
Expired / Lapsed
US
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Method for recovering concentrated sulphur dioxide from waste gases containing sulphur dioxide
Assignee: Svenska Flaktfabriken AB
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Filing: 1978-04-06
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Granted: 1980-01-01
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Expires: 1998-04-06
Abstract
Abstract Improved efficiency in recovering SO 2 from waste gases is obtained in a system where the SO 2 is absorbed into a solution which is then distilled. The method of this application entails compressing the steam-SO 2 mixture issuing from the still before condensing out the steam, so that the heat from the compressed steam-SO 2 mixture may be used in generating the steam for the still, and the condensate may be recycled through the still, preferably after reheating the same.
Inventors
- 👤 Sune Bengtsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:11
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/48; C01B17/50; C01B17/60
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
84 words
A method of recovering the concentrated sulphur dioxide from waste gases containing SO 2 , by treating the gas with water or aqueous solutions of substances binding sulphur dioxide in an absorption device, characterized by the steps of feeding the solution rich in absorbed SO 2 into a column still and distilling it with steam, compressing the steam-SO 2 mixture discharged from the still, and at least partially condensing the steam in a heat exchanger re-boiler where steam ingoing to the still is generated.
Claim 2
Independent Claim
84 words
A method of recovering the concentrated sulphur dioxide from waste gases containing SO 2 , by treating the gas with water or aqueous solutions of substances binding sulphur dioxide in an absorption device, characterized by the steps of feeding the solution rich in absorbed SO 2 into a column still and distilling it with steam, compressing the steam-SO 2 mixture discharged from the still, and at least partially condensing the steam in a heat exchanger re-boiler where steam ingoing to the still is generated.
Claim 3
Dependent Claim
25 words
A method according to claim 1, characterized in that the compression of steam-SO 2 mixture outgoing from the still is carried out in an ejector.
Claim 4
Dependent Claim
26 words
A method according to claim 1, characterized in that the compression of steam-SO 2 mixture outgoing from the still is carried out in a mechanical compressor.
Claim 5
Dependent Claim
21 words
A method according to claim 1, characterized in that the temperature in the still is maintained between 40° and 130° C.
Claim 6
Dependent Claim
27 words
A method according to claim 1, characterized in that the steam-SO 2 mixture is led from the reboiler to a cooler where the remaining system is condensed.
Claim 7
Dependent Claim
29 words
A method according to claim 5, characterized in that the condensate from re-boiler and cooler is combined with the SO 2 -containing solution which is fed to the still.
Claim 8
Dependent Claim
28 words
A method according to claim 1, characterized in that solution discharged from the still is heat exchanged with solution rich in SO 2 being fed into the still.
Claim 9
Dependent Claim
56 words
A method according to claim 7, characterized in that the temperature of fed solution going into the still is increased such that the temperature of the fed solution has a temperature substantially equal to the temperature prevailing at the bottom of the still after heat exchange of the fed solution with solution discharged from the still.
Claim 10
Dependent Claim
34 words
A method according to claim 1 or 8, characterized in that the temperature of the condensate from the re-boiler is increased and then is fed into the still with the SO 2 -containing solution.
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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) | 1982-12-31 | 1983-07-02 | 1984-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-31 | 1987-07-02 | 1988-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-31 | 1991-07-02 | 1992-01-01 | $7700.00 | Window Closed / Lapsed |