EP0252893A2
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Method of reducing the content of nitrogen oxides in multiple bed combustion boilers
Assignee: ABB Stal AB
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Filing: 1987-07-08
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Granted: —
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Expires: 2007-07-08
Abstract
Abstract Method of supplying ammonia gas to boilers having at least two fluidized beds one above the other for reducing the content of nitrogen oxides in the flue gas wherein the ammonia gas is intermixed with secondary air or tertiary air before said air intermixed with flue gas from the lower fluidized bed is supplied to the upper fluidized bed or the upper fluidized beds, respectively, for fluidization equally distributed over the area of the bed or beds, respectively.
Inventors
- 👤 Jörgen Bergkvist
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 08:06
CPC Classifications
F; F23; F23C; F23C10/00; F23J; F23J7/00; F23C10/005; F23C10/18
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
103 words
Method of supplying ammonia gas to boilers having at least two fluidized beds, one located above the other, for reducing the content of nitrogen oxides in the flue gas, characterized in that the ammonia gas is intermixed with secondary air and/or tertiary air which is then supplied to a plurality of individual flue gas streams flowing from a lower fluidized bed from below into an upper fluidized bed, distributed over the area of the upper bed, said upper bed being fluidized by means of the gas streams consisting of flue gas and secondary air and/or tertiary air, respectively, having ammonia gas intermixed therewith.
Claim 2
Dependent Claim
103 words
Method of supplying ammonia gas to boilers having at least two fluidized beds, one located above the other, for reducing the content of nitrogen oxides in the flue gas, characterized in that the ammonia gas is intermixed with secondary air and/or tertiary air which is then supplied to a plurality of individual flue gas streams flowing from a lower fluidized bed from below into an upper fluidized bed, distributed over the area of the upper bed, said upper bed being fluidized by means of the gas streams consisting of flue gas and secondary air and/or tertiary air, respectively, having ammonia gas intermixed therewith.
Claim 3
Dependent Claim
26 words
Method as in claim 1 wherein the admixture of ammonia gas to the secondary air and/or tertiary air, respectively, is adapted to the prevailing air flow.
Claim 4
Dependent Claim
27 words
Method as in claim 1 wherein the admixture of ammonia gas to the secondary air and/or tertiary air, respectively, is adapted to the prevailing flue gas temperature.
Claim 5
Dependent Claim
31 words
Method as in claim 1 wherein the amount of admixed ammonia gas is adapted to the prevailing content of nitrogen oxides, the prevailing air flow, and the prevailing flue gas temperature.
Claim 6
Dependent Claim
25 words
Method as in claim 1 wherein the amount of admixed ammonia gas is limited by the residual amount of ammonia in the escaping flue gas.
References Cited (Backward Citations)
No citation records indexed.
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