Claims
- 1. A method to increase the throughput of a recovery boiler equipped with at least primary and secondary levels of injection of air, the method comprising operating the recovery boiler with a third level of oxidant injection below or at the same level as the secondary level, and oxygen enrichment applied to at least the secondary level and said third level.
- 2. Method in accordance with claim 1 wherein the third level is placed at or close to a level where black liquor injection ports are positioned in the boiler.
- 3. Method in accordance with claim 1 comprising injecting the third level at the same level as the secondary level of injection of air, using new oxidant nozzles.
- 4. Method in accordance with claim 1 wherein the third level is operated at a level lower than a level where black liquor injection ports are positioned in the boiler and higher than the primary level of injection of air.
- 5. Method in accordance with claim 1 wherein the recovery boiler has oxygen concentrations up to 30% in at least the secondary level of injection of air.
- 6. A method in accordance with claim 1 wherein the third level of oxidant injection is at a level lower than a level of injection of black liquor but higher than the primary level of injection of air.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 08/937,290, filed Sep. 26, 1997, now U.S. Pat. No. 5,992,337, which is incorporated by reference herein in its entirety.
US Referenced Citations (11)
Foreign Referenced Citations (5)
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May 1994 |
EP |
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Non-Patent Literature Citations (2)
Entry |
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Continuations (1)
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Number |
Date |
Country |
Parent |
08/937290 |
Sep 1997 |
US |
Child |
09/392418 |
|
US |