US4364915A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for recovery of carbon dioxide from flue gas
Assignee: Procon International Inc
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Filing: 1981-05-21
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Granted: 1982-12-21
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Expires: 2001-05-21
Abstract
Abstract A process for the recovery of carbon dioxide from a flue gas stream containing residual oxygen is disclosed. A combustible fuel, such as methane, is admixed with the flue gas stream and the flue gas stream is then passed into a combustion zone in which it may be contacted with a catalyst which promotes the consumption of the residual oxygen in a combustion reaction. Preferably, the heat liberated in the combustion reaction is recovered for use in heating flue gas to combustion supporting conditions and in downstream carbon dioxide recovery steps. The purpose of the combustion reaction is to lower the oxygen content of the flue gas stream, which is then contacted with a lean carbon dioxide absorbing amine solution. The low oxygen content reduces the degradation of the amine solution and the corrosiveness of the amine solution thus allowing the use of high strength amine solutions and very high absorbent liquid loadings.
Inventors
- 👤 Russell C. Proctor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:27
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/343; B01D53/14; B01D53/1456; B01D53/1475; C; C01; C01B; C01B32/00; C01B32/50; Y; Y02; Y02C; Y02C20/00; Y02C20/40; Y02P; Y02P20/00; Y02P20/151
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
96 words
A process for recovering carbon dioxide from a flue gas stream which comprises the steps of: (a) admixing a combustible fuel into a flue gas stream; (b) passing the flue gas stream through a combustion zone in which the combustible fuel is reacted with oxygen originally present in the flue gas stream; (c) cooling the flue gas stream; (d) contacting the flue gas stream with a lean absorber liquid comprising an aqueous amine solution which absorbs carbon dioxide at carbon dioxide absorbing conditions in a contacting zone; and, (e) recovering carbon dioxide from the absorber liquid.
Claim 2
Dependent Claim
96 words
A process for recovering carbon dioxide from a flue gas stream which comprises the steps of: (a) admixing a combustible fuel into a flue gas stream; (b) passing the flue gas stream through a combustion zone in which the combustible fuel is reacted with oxygen originally present in the flue gas stream; (c) cooling the flue gas stream; (d) contacting the flue gas stream with a lean absorber liquid comprising an aqueous amine solution which absorbs carbon dioxide at carbon dioxide absorbing conditions in a contacting zone; and, (e) recovering carbon dioxide from the absorber liquid.
Claim 3
Dependent Claim
28 words
The process of claim 1 further characterized in that the flue gas stream is heated prior to the admixture of the combustible fuel into the flue gas stream.
Claim 4
Dependent Claim
36 words
The process of claim 2 further characterized in that the flue gas stream is heated by indirect heat exchange against at least a portion of the flue gas stream which has passed through the combustion zone.
Claim 5
Dependent Claim
37 words
The process of claim 3 further characterized in that the combustion zone does not contain a bed of a combustion catalyst and in that the oxygen content of the flue gas stream is reduced by thermal deoxidation.
Claim 6
Dependent Claim
19 words
The process of claim 3 further characterized in that the combustion zone contains a bed of a combustion catalyst.
Claim 7
Dependent Claim
25 words
The process of claim 1 further characterized in that the flue gas stream contains less than 200 ppm oxygen after passage through the combustion zone.
Claim 8
Dependent Claim
25 words
The process of claim 4 further characterized in that the flue gas stream contains less than 100 ppm oxygen after passage through the combustion zone.
Claim 9
Dependent Claim
21 words
The process of claim 1 further characterized in that the flue gas stream is passed through two combustion zones in series.
Claim 10
Dependent Claim
25 words
The process of claim 8 further characterized in that the flue gas stream is cooled and admixed with additional fuel between the two combustion zones.
Claim 11
Dependent Claim
19 words
The process of claim 1 further characterized in that the aqueous amine solution contains at least 20 wt.% monoethanolamine.
Claim 12
Dependent Claim
14 words
The process of claim 10 further characterized in that the absorber liquid comprises monoethanolamine.
Claim 13
Dependent Claim
23 words
The process of claim 1 further characterized in that the flue gas stream entering the process contains more than 2 mole percent oxygen.
Claim 14
Dependent Claim
158 words
A process for recovering carbon dioxide from a flue gas stream which comprises the steps of: (a) heating a flue gas stream by indirect heat exchange against a hereinafter characterized relatively hot gas stream; (b) admixing a combustible fuel into the flue gas stream; (c) passing the flue gas stream through a combustion zone in which the flue gas stream is contacted with a combustion catalyst at combustion-promoting conditions and thereby reducing the oxygen content of the flue gas stream to less than 200 ppm; (d) cooling at least a portion of the flue gas stream by indirect heat exchange as the previously specified relatively hot gas stream of step (a); (e) contacting the flue gas stream with a lean carbon dioxide absorbing liquid comprising an aqueous amine solution in an absorption zone operated at absorption-promoting conditions and thereby forming a rich carbon dioxide absorbing liquid; and, (f) recovering carbon dioxide from the rich carbon dioxide absorbing liquid.
Claim 15
Dependent Claim
158 words
A process for recovering carbon dioxide from a flue gas stream which comprises the steps of: (a) heating a flue gas stream by indirect heat exchange against a hereinafter characterized relatively hot gas stream; (b) admixing a combustible fuel into the flue gas stream; (c) passing the flue gas stream through a combustion zone in which the flue gas stream is contacted with a combustion catalyst at combustion-promoting conditions and thereby reducing the oxygen content of the flue gas stream to less than 200 ppm; (d) cooling at least a portion of the flue gas stream by indirect heat exchange as the previously specified relatively hot gas stream of step (a); (e) contacting the flue gas stream with a lean carbon dioxide absorbing liquid comprising an aqueous amine solution in an absorption zone operated at absorption-promoting conditions and thereby forming a rich carbon dioxide absorbing liquid; and, (f) recovering carbon dioxide from the rich carbon dioxide absorbing liquid.
Claim 16
Dependent Claim
15 words
The process of claim 13 further characterized in that the aqueous amine solution comprises monoethanolamine.
Claim 17
Dependent Claim
18 words
The process of claim 13 further characterized in that the amine solution contains at least 20 wt.% monoethanolamine.
Claim 18
Dependent Claim
33 words
The process of claim 13 further characterized in that the flue gas stream is passed through two combustion zones in series and is admixed with additional combustible fuel between the two combustion zones.
Claim 19
Dependent Claim
14 words
The process of claim 16 further characterized in that the combustible fuel comprises methane.
Claim 20
Dependent Claim
14 words
The process of claim 16 further characterized in that the combustible fuel comprises propane.
Claim 21
Dependent Claim
15 words
The process of claim 20 further characterized in that the combustible fuel comprises carbon monoxide.
Claim 22
Dependent Claim
48 words
The process of claim 13 further characterized in that at least a portion of the heat expended in the recovery of carbon dioxide from the rich carbon dioxide absorbing liquid is obtained from the flue gas stream after the flue gas stream has passed through the combustion zone.
Claim 23
Dependent Claim
52 words
The process of claim 14 further characterized in that carbon dioxide is recovered by passing the rich carbon dioxide absorbing liquid into a regeneration zone which is reboiled with heat recovered by indirect heat exchange against the flue gas stream at a point downstream of the initial cooling performed in step (d).
Claim 24
Dependent Claim
119 words
A process for recovering carbon dioxide from a flue gas stream which comprises the step of: (a) heating a flue gas stream by indirect heat exchange; (b) admixing a combustible fuel into the flue gas stream and passing the flue gas stream through a combustion zone maintained at thermal deoxidation conditions and thereby reducing the oxygen content of the flue gas stream; (c) cooling the flue gas stream by indirect heat exchange; (d) contacting the flue gas stream with a lean carbon dioxide absorbing liquid comprising an aqueous amine solution in an absorption zone operated at absorption-promoting conditions and thereby forming a rich carbon dioxide absorbing liquid; and, (e) recovering carbon dioxide from the rich carbon dioxide absorbing liquid.
Claim 25
Dependent Claim
119 words
A process for recovering carbon dioxide from a flue gas stream which comprises the step of: (a) heating a flue gas stream by indirect heat exchange; (b) admixing a combustible fuel into the flue gas stream and passing the flue gas stream through a combustion zone maintained at thermal deoxidation conditions and thereby reducing the oxygen content of the flue gas stream; (c) cooling the flue gas stream by indirect heat exchange; (d) contacting the flue gas stream with a lean carbon dioxide absorbing liquid comprising an aqueous amine solution in an absorption zone operated at absorption-promoting conditions and thereby forming a rich carbon dioxide absorbing liquid; and, (e) recovering carbon dioxide from the rich carbon dioxide absorbing liquid.
Claim 26
Dependent Claim
43 words
The process of claim 22 further characterized in that the flue gas stream is heated prior to passage into the combustion zone by indirect heat exchange against at least a portion of the flue gas stream which has passed through the combustion zone.
Claim 27
Dependent Claim
26 words
The process of claim 23 further characterized in that the flue gas stream comprises less than 200 ppm oxygen after having passed through the combustion zone.
Claim 28
Dependent Claim
23 words
The process of claim 22 further characterized in that the carbon dioxide absorbing liquid comprises an aqueous solution comprising 20 wt.% of monoethanolamine.
References Cited (Backward Citations)
CA504620A
Cited
USRE18958E
Cited
US2593530A
Cited
US2668748A
Cited
US3317278A
Cited
US3690816A
Cited
US3959170A
Cited
US3820965A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-20 | 1986-06-21 | 1986-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-20 | 1990-06-21 | 1990-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-20 | 1994-06-21 | 1994-12-21 | $7700.00 | Window Closed / Lapsed |