US4042348A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of conditioning flue gas to electrostatic precipitator
Assignee: Ecolab Inc
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Filing: 1976-08-02
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Granted: 1977-08-16
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Expires: 1996-08-02
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 ammonium bisulfate into a particle-laden gas stream formed by the burning of coal while the gas has a temperature of 590-900° C. Sufficient ammonium 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
- 👤 Matthew J. O'Connor
- 👤 Alfred E. Kober
- 👤 Ira Kukin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:13
CPC Classifications
B; B03; B03C; B03C3/00; B03C3/01; B03C3/013
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
92 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 an electrostatic precipitator, comprising forming a mixture of A. the particle-laden gas at a temperature of 590°-900° C., and B. finely divided ammonium sulfate; said mixture containing 75-1250 grams of ammonium sulfate per metric ton of coal burned to form said gas, and C. after forming said mixture, directing said gas stream through a heat exchange means and into an electrostatic precipitator to collect said particles therein.
Claim 2
Independent Claim
92 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 an electrostatic precipitator, comprising forming a mixture of A. the particle-laden gas at a temperature of 590°-900° C., and B. finely divided ammonium sulfate; said mixture containing 75-1250 grams of ammonium sulfate per metric ton of coal burned to form said gas, and C. after forming said mixture, directing said gas stream through a heat exchange means and into an electrostatic precipitator to collect said particles therein.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein said mixture contains 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 4
Dependent Claim
42 words
The method of claim 1 wherein said ammonium bisulfate is mixed with said gas in the form of an aqueous solution and in sufficient quantity to provide 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 5
Dependent Claim
24 words
The method of claim 1 wherein said gas is at a temperature of 590°-750° C. at the time said ammonium bisulfate is mixed therewith.
Claim 6
Dependent Claim
42 words
The method of claim 4 wherein said ammonium bisulfate is mixed with said gas in the form of an aqueous solution and in sufficient quantity to provide 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 7
Dependent Claim
24 words
The method of claim 4 wherein said mixture contains 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein said ammonium bisulfate is mixed with said gas in the form of an aqueous solution.
Claim 9
Dependent Claim
23 words
The method of claim 7 wherein said aqueous solution comprises about 20-50 parts of ammonium bisulfate and 50-80 parts by weight of water.
Claim 10
Dependent Claim
24 words
The method of claim 7 wherein said mixture contains 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 11
Dependent Claim
17 words
The method of claim 1 wherein said ammonium bisulfate is in the form of a dry powder.
Claim 12
Dependent Claim
24 words
The method of claim 10 wherein said mixture contains 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 13
Dependent Claim
17 words
The method of claim 1 including the additional step of passing said mixture through heat exchange means.
Claim 14
Dependent Claim
42 words
The method of claim 12 wherein said ammonium bisulfate is mixed with said gas in the form of an aqueous solution and in sufficient quantity to provide 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 15
Independent Claim
99 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 an electrostatic precipitator, comprising the steps of: A. injecting finely divided ammonium bisulfate into said stream of particle-laden gas while said gas has a temperature of 590°-900° C., sufficient ammonium bisulfate being injected to provide 75-1250 grams of ammonium 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 and into an electrostatic precipitator to collect said particles therein.
Claim 16
Independent Claim
99 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 an electrostatic precipitator, comprising the steps of: A. injecting finely divided ammonium bisulfate into said stream of particle-laden gas while said gas has a temperature of 590°-900° C., sufficient ammonium bisulfate being injected to provide 75-1250 grams of ammonium 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 and into an electrostatic precipitator to collect said particles therein.
Claim 17
Dependent Claim
39 words
The method of claim 14 wherein said ammonium bisulfate is injected in the form of an aqueous solution and in sufficient quantity to provide 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 18
Dependent Claim
20 words
The method of claim 14 wherein said gas is at a temperature of 590°-750° C. at the point of injection.
Claim 19
Dependent Claim
23 words
The method of claim 16 wherein 150-600 grams of ammonium bisulfate are injected per metric ton of coal burned to form said gas.
Claim 20
Dependent Claim
39 words
The method of claim 16 wherein said ammonium bisulfate is injected in the form of an aqueous solution and in sufficient quantity to provide 150-600 grams of ammonium bisulfate per metric ton of coal burned to form said gas.
Claim 21
Dependent Claim
18 words
The method of claim 14 wherein said ammonium bisulfate is injected in the form of an aqueous solution.
Claim 22
Dependent Claim
23 words
The method of claim 19 wherein said aqueous solution comprises about 20-50 parts of ammonium bisulfate and 50-80 parts by weight of water.
Claim 23
Dependent Claim
23 words
The method of claim 19 wherein 150-600 grams of ammonium bisulfate are injected per metric ton of coal burned to form said gas.
Claim 24
Dependent Claim
18 words
The method of claim 14 wherein said ammonium bisulfate is injected in the form of a dry powder.
Claim 25
Dependent Claim
23 words
The method of claim 22 wherein 150-600 grams of ammonium bisulfate are injected per metric ton of coal burned to form said gas.
Claim 26
Dependent Claim
23 words
The method of claim 14 wherein 150-600 grams of ammonium bisulfate are injected per metric ton of coal burned to form said gas.
Claim 27
Independent Claim
89 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 an electrostatic precipitator, comprising forming a mixture of A. the particle-laden gas at a temperature of 590°-900° C., and B. finely divided ammonium sulfate; said mixture containing 2.46-41.1 kilograms of said ammonium sulfate per million cubic meters of said gas at 649° C., and thereafter directing said gas stream through a heat exchange means and into an electrostatic precipitator to collect said particles therein.
Claim 28
Independent Claim
89 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 an electrostatic precipitator, comprising forming a mixture of A. the particle-laden gas at a temperature of 590°-900° C., and B. finely divided ammonium sulfate; said mixture containing 2.46-41.1 kilograms of said ammonium sulfate per million cubic meters of said gas at 649° C., and thereafter directing said gas stream through a heat exchange means and into an electrostatic precipitator to collect said particles therein.
Claim 29
Dependent Claim
25 words
The method of claim 25 wherein said mixture contains 4.93-19.71 kilograms of said ammonium bisulfate per million cubic meters of said gas at 649° C.
Claim 30
Independent Claim
92 words
A method of improving the collection characteristics of particles entrained in a particle-laden gas stream for collection by an electrostatic precipitator, comprising the steps of: A. injecting finely divided ammonium bisulfate into a stream of particle-laden gas while said gas has a temperature of 590°-900° C., sufficient ammonium bisulfate being injected to provide 2.46-41.1 kilograms of ammonium bisulfate per million cubic meters of said gas at 649° C.; and B. after said injection, directing said gas stream through a heat exchange means and into an electrostatic precipitator to collect said particles therein.
Claim 31
Independent Claim
92 words
A method of improving the collection characteristics of particles entrained in a particle-laden gas stream for collection by an electrostatic precipitator, comprising the steps of: A. injecting finely divided ammonium bisulfate into a stream of particle-laden gas while said gas has a temperature of 590°-900° C., sufficient ammonium bisulfate being injected to provide 2.46-41.1 kilograms of ammonium bisulfate per million cubic meters of said gas at 649° C.; and B. after said injection, directing said gas stream through a heat exchange means and into an electrostatic precipitator to collect said particles therein.
Claim 32
Dependent Claim
24 words
The method of claim 27 wherein 4.93-19.71 kilograms of said ammonium 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) | 1980-08-15 | 1981-02-14 | 1981-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-15 | 1985-02-14 | 1985-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-15 | 1989-02-14 | 1989-08-16 | $7700.00 | Window Closed / Lapsed |