US4113447A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of conditioning flue gas
Assignee: Ecolab Inc
•
Filing: 1977-05-02
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Granted: 1978-09-12
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Expires: 1997-05-02
Abstract
Abstract The collection characteristics of particles entrained in a particle-laden gas for collection by an electrostatic precipitator are improved by injecting finely divided sodium bisulfate into a particle-laden gas stream formed by the burning of coal while the gas has a temperature of 200°-900° C. Sufficient sodium bisulfate is injected to provide 75-1250 grams per metric ton of coal burned to form the gas. After injection, the stream is directed through a heat exchange means and finally into the precipitator to collect the particles therein.
Inventors
- 👤 Robert P. Bennett
- 👤 Alfred E. Kober
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:21
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/01; B03C3/013
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
61 words
A method of conditioning a particle-laden gas formed by the burning of coal comprising forming a mixture of: (A) the particle-laden gas at a temperature of 200°-900° C., and (B) finely divided sodium bisulfate; said mixture containing 75-1250 grams of sodium bisulfate per metric ton of coal burned to form said gas; and thereafter passing the mixture through an electrostatic precipitator.
Claim 2
Independent Claim
61 words
A method of conditioning a particle-laden gas formed by the burning of coal comprising forming a mixture of: (A) the particle-laden gas at a temperature of 200°-900° C., and (B) finely divided sodium bisulfate; said mixture containing 75-1250 grams of sodium bisulfate per metric ton of coal burned to form said gas; and thereafter passing the mixture through an electrostatic precipitator.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein said gas is at a temperature of 350°-750° C. at the time said sodium bisulfate is mixed therewith.
Claim 4
Dependent Claim
42 words
The method of claim 2 wherein said sodium bisulfate is mixed with said gas in the form of an aqueous solution and in sufficient quantity to provide 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 5
Dependent Claim
24 words
The method of claim 2 wherein said mixture contains 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein said sodium bisulfate is mixed with said gas in the form of an aqueous solution.
Claim 7
Dependent Claim
24 words
The method of claim 5 wherein said mixture contains 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 8
Dependent Claim
23 words
The method of claim 5 wherein said aqueous solution comprises about 10-40 parts of sodium bisulfate and 60-90 parts by weight of water.
Claim 9
Dependent Claim
18 words
The method of claim 7 wherein said sodium bisulfate is injected in the form of a dry powder.
Claim 10
Dependent Claim
23 words
The method of claim 8 wherein 200-1000 grams of sodium bisulfate are injected per metric ton of coal burned to form said gas.
Claim 11
Dependent Claim
17 words
The method of claim 1 wherein said sodium bisulfate is in the form of a dry powder.
Claim 12
Dependent Claim
24 words
The method of claim 10 wherein said mixture contains 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 13
Dependent Claim
24 words
The method of claim 1 wherein said mixture contains 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 14
Dependent Claim
42 words
The method of claim 1 wherein said sodium bisulfate is mixed with said gas in the form of an aqueous solution and in sufficient quantity to provide 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 15
Dependent Claim
17 words
The method of claim 1 including the additional step of passing said mixture through heat exchange means.
Claim 16
Dependent Claim
42 words
The method of claim 14 wherein said sodium bisulfate is mixed with said gas in the form of an aqueous solution and in sufficient quantity to provide 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 17
Independent Claim
98 words
A method of improving the collection characteristics of particles entrained in a stream of particle-laden gas formed by the burning of coal for collection by and electrostatic precipitator, comprising the steps of: (A) injecting finely divided sodium bisulfate into said stream of particle-laden gas while said gas has a temperature of 200°-900° C., sufficient sodium bisulfate being injected to provide 75-1250 grams of sodium bisulfate per metric ton of coal burned to form said gas; and (B) after said injection, directing said gas stream through a heat exchange means into an electrostatic precipitator to collect said particles therein.
Claim 18
Independent Claim
98 words
A method of improving the collection characteristics of particles entrained in a stream of particle-laden gas formed by the burning of coal for collection by and electrostatic precipitator, comprising the steps of: (A) injecting finely divided sodium bisulfate into said stream of particle-laden gas while said gas has a temperature of 200°-900° C., sufficient sodium bisulfate being injected to provide 75-1250 grams of sodium bisulfate per metric ton of coal burned to form said gas; and (B) after said injection, directing said gas stream through a heat exchange means into an electrostatic precipitator to collect said particles therein.
Claim 19
Dependent Claim
20 words
The method of claim 16 wherein said gas is at a temperature of 350°-750° C. at the point of injection.
Claim 20
Dependent Claim
23 words
The method of claim 17 wherein 200-1000 grams of sodium bisulfate are injected per metric ton of coal burned to form said gas.
Claim 21
Dependent Claim
39 words
The method of claim 16 wherein said sodium bisulfate is injected in a form of an aqueous solution and in sufficient quantity to provide 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 22
Dependent Claim
39 words
The method of claim 17 wherein said sodium bisulfate is injected in a form of an aqueous solution and in sufficient quantity to provide 200-1000 grams of sodium bisulfate per metric ton of coal burned to form said gas.
Claim 23
Dependent Claim
18 words
The method of claim 16 wherein said sodium bisulfate is injected in the form of an aqueous solution.
Claim 24
Dependent Claim
23 words
The method of claim 21 wherein said aqueous solution comprises about 10-40 parts of sodium bisulfate and 60-90 parts by weight of water.
Claim 25
Dependent Claim
23 words
The method of claim 21 wherein 200-1000 grams of sodium busulfate are injected per metric ton of coal burned to form said gas.
Claim 26
Dependent Claim
23 words
The method of claim 16 wherein 200-1000 grams of sodium bisulfate are injected per metric ton of coal burned to form said gas.
Claim 27
Independent Claim
62 words
A method of conditioning a particle-laden gas formed by the burning of coal comprising forming a mixture of: (A) a particle-laden gas at a temperature of 200-900° C., and (B) finely divided sodium bisulfate; said mixture containing 2.45-41.1 kilograms of said sodium bisulfate per million cubic meters of said gas at 649° C.; and thereafter passing said mixtue through an electrostatic precipitator.
Claim 28
Independent Claim
62 words
A method of conditioning a particle-laden gas formed by the burning of coal comprising forming a mixture of: (A) a particle-laden gas at a temperature of 200-900° C., and (B) finely divided sodium bisulfate; said mixture containing 2.45-41.1 kilograms of said sodium bisulfate per million cubic meters of said gas at 649° C.; and thereafter passing said mixtue through an electrostatic precipitator.
Claim 29
Dependent Claim
25 words
The method of claim 25 wherein said mixture contains 6.56-32.9 kilograms of said sodium bisulfate per million cubic meters of said gas at 649° C.
Claim 30
Independent Claim
91 words
A method of improving the collection characteristics of particle entrained in a particle-laden gas stream for collection by an electrostatic precipitator, comprising the steps of: (A) injecting finely divided sodium bisulfate into a stream of particle-laden gas while said gas has a temperature of 200-900° C., sufficient sodium bisulfate being injected to provide 2.46-41.1 kilograms of sodium bisulfate per million cubic meters of said gas at 649° C.; (b) after said injection, directing said gas stream through a heat exchange means and into and electrostatic precipitator to collect said particles thereon.
Claim 31
Independent Claim
91 words
A method of improving the collection characteristics of particle entrained in a particle-laden gas stream for collection by an electrostatic precipitator, comprising the steps of: (A) injecting finely divided sodium bisulfate into a stream of particle-laden gas while said gas has a temperature of 200-900° C., sufficient sodium bisulfate being injected to provide 2.46-41.1 kilograms of sodium bisulfate per million cubic meters of said gas at 649° C.; (b) after said injection, directing said gas stream through a heat exchange means and into and electrostatic precipitator to collect said particles thereon.
Claim 32
Dependent Claim
24 words
The method of claim 27 wherein 6.56-32.9 kilograms of said sodium bisulfate are injected per million cubic meters of said gas at 649° C.
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) | 1981-09-11 | 1982-03-13 | 1982-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-11 | 1986-03-13 | 1986-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-11 | 1990-03-13 | 1990-09-12 | $7700.00 | Window Closed / Lapsed |