Improving limestone utilization in a commercial-scale circulating fluidized bed boiler through ash reactivation and recycle
From earlier bench-scale and pilot-scale studies, it has been recognized that the partially reacted sorbent present in the ash can be further utilized by various ash recycle processes, such as dry ash recycle or reactivated ash recycle. The ash hydration process, simply mixing ash and water together, has been one of most feasible methods to reactivate the spent sorbent. The hydration process increases the accessibility of the unused calcium oxide in sorbent particle to sulfur dioxide. Field tests on the hydrated ash recycle were conducted in a Foster Wheeler commercial-scale circulating fluidized bed boiler. The effect of hydrated ash vs. dry ash recycle and fly ash vs. bottom ash recycle on boiler efficiency, limestone consumption and NO{sub x} emissions were investigated. Test results in these field tests showed that about 10--20% limestone saving can be achieved without any negative effect on boiler efficiency. It also demonstrated that the ash hydration process can be done with a very simple system without any ash handling and environmental concerns.
- Research Organization:
- Foster Wheeler Development Corp., Livingston, NJ (US)
- OSTI ID:
- 20006793
- Report Number(s):
- CONF-990534-; TRN: IM200008%%400
- Resource Relation:
- Conference: 15th International Conference on Fluidized Bed Combustion, Savannah, GA (US), 05/16/1999--05/19/1999; Other Information: 1 CD-ROM. Operating system required: Windows 3.x; Windows 95/98/NT; Macintosh, Power Macintosh; UNIX. All systems need 2X CD-ROM drive.; PBD: 1999; Related Information: In: Proceedings of the 15th national conference on fluidized bed combustion, by Reuther, R.B. [ed.], [1800] pages.
- Country of Publication:
- United States
- Language:
- English
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