Effect of residence time on feed utilization in a circulating fluidized bed boiler
Abstract
A key operating parameter for circulating fluidized bed boilers is the bed quality, which is influences operating characteristics such as temperature control and feedstock utilization. In order to extend our understanding of feedstock utilization at our Stockton circulating fluidized bed boiler, the composition of fly ash and bottom ash was analyzed as a function of particle size. Results for two coal and limestone feeds demonstrate that carbon burnout and limestone conversion depend strongly on particle size. Some of the findings are contrary to general understanding. The authors of this paper observed that the majority of free carbon is found not in the bottom ash, but as a dilute constituent of the finer particles of fly ash. Furthermore, small limestone particles are less effective for sulfur capture, despite their high surface-to-volume ratio. These observations are reconciled by quantifying the relationship between particle size and particle residence time in the boiler. The residence time is shown to vary over four orders of magnitude, and is the controlling feature for feed utilization.
- Authors:
-
- Air Products and Chemicals, Inc., Allentown, PA (United States)
- Publication Date:
- OSTI Identifier:
- 5084203
- Report Number(s):
- CONF-9104106-
Journal ID: ISSN 0097-2126; CODEN: PAPWA
- Resource Type:
- Conference
- Journal Name:
- Proceedings of the American Power Conference; (United States)
- Additional Journal Information:
- Journal Volume: 53; Conference: 53. annual American power conference, Chicago, IL (United States), 29 Apr - 1 May 1991; Journal ID: ISSN 0097-2126
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 20 FOSSIL-FUELED POWER PLANTS; 42 ENGINEERING; FLUIDIZED BED BOILERS; FUEL CONSUMPTION; OPERATION; FOSSIL-FUEL POWER PLANTS; ASHES; CIRCULATING SYSTEMS; LIMESTONE; PARTICLE SIZE; PARTICULATES; SULFUR; BOILERS; CARBONATE ROCKS; COMBUSTION PRODUCTS; ELEMENTS; ENERGY CONSUMPTION; NONMETALS; PARTICLES; POWER PLANTS; RESIDUES; ROCKS; SEDIMENTARY ROCKS; SIZE; THERMAL POWER PLANTS; 200108* - Fossil-Fueled Power Plants- Fuels- (1980-); 420400 - Engineering- Heat Transfer & Fluid Flow
Citation Formats
Lewnard, J J, Wong, K P, Tsao, T R, and Wang, S I. Effect of residence time on feed utilization in a circulating fluidized bed boiler. United States: N. p., 1991.
Web.
Lewnard, J J, Wong, K P, Tsao, T R, & Wang, S I. Effect of residence time on feed utilization in a circulating fluidized bed boiler. United States.
Lewnard, J J, Wong, K P, Tsao, T R, and Wang, S I. 1991.
"Effect of residence time on feed utilization in a circulating fluidized bed boiler". United States.
@article{osti_5084203,
title = {Effect of residence time on feed utilization in a circulating fluidized bed boiler},
author = {Lewnard, J J and Wong, K P and Tsao, T R and Wang, S I},
abstractNote = {A key operating parameter for circulating fluidized bed boilers is the bed quality, which is influences operating characteristics such as temperature control and feedstock utilization. In order to extend our understanding of feedstock utilization at our Stockton circulating fluidized bed boiler, the composition of fly ash and bottom ash was analyzed as a function of particle size. Results for two coal and limestone feeds demonstrate that carbon burnout and limestone conversion depend strongly on particle size. Some of the findings are contrary to general understanding. The authors of this paper observed that the majority of free carbon is found not in the bottom ash, but as a dilute constituent of the finer particles of fly ash. Furthermore, small limestone particles are less effective for sulfur capture, despite their high surface-to-volume ratio. These observations are reconciled by quantifying the relationship between particle size and particle residence time in the boiler. The residence time is shown to vary over four orders of magnitude, and is the controlling feature for feed utilization.},
doi = {},
url = {https://www.osti.gov/biblio/5084203},
journal = {Proceedings of the American Power Conference; (United States)},
issn = {0097-2126},
number = ,
volume = 53,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1991},
month = {Tue Jan 01 00:00:00 EST 1991}
}