A model of coal particle drying in fluidized bed combustion reactor
Abstract
Experimental and theoretical investigation on drying of a single coal particle in fluidized bed combustor is presented. Coal particle drying was considered via the moist shrinking core mechanism. The results of the drying test runs of low-rank Serbian coals were used for experimental verification of the model. The temperature of the coal particle center was measured, assuming that drying was completed when the temperature equalled 100{sup o}C. The influence of different parameters (thermal conductivity and specific heat capacity of coal, fluidized bed temperature, moisture content and superheating of steam) on drying time and temperature profile within the coal particle was analyzed by a parametric analysis. The experimentally obtained results confirmed that the moist shrinking core mechanism can be applied for the mathematical description of a coal particle drying, while dependence between drying time and coal particle radius, a square law relationship, implicates heat transfer control of the process and confirms the validity of assumptions used in modeling.
- Authors:
- Natural Resources Canada, Ottawa, ON (Canada). CANMET, Energy Technology Centre
- Publication Date:
- OSTI Identifier:
- 20885779
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Energy Sources, Part A: Recovery, Utilization, and Environmental Effects; Journal Volume: 29; Journal Issue: 3
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 01 COAL, LIGNITE, AND PEAT; FLUIDIZED-BED COMBUSTORS; PARTICLES; COAL; DRYING; PARAMETRIC ANALYSIS; MATHEMATICAL MODELS; FLUIDIZED BEDS; BROWN COAL; LIGNITE
Citation Formats
Komatina, M., Manovic, V., and Saljnikov, A. A model of coal particle drying in fluidized bed combustion reactor. United States: N. p., 2007.
Web. doi:10.1080/00908310600688796.
Komatina, M., Manovic, V., & Saljnikov, A. A model of coal particle drying in fluidized bed combustion reactor. United States. doi:10.1080/00908310600688796.
Komatina, M., Manovic, V., and Saljnikov, A. Thu .
"A model of coal particle drying in fluidized bed combustion reactor". United States.
doi:10.1080/00908310600688796.
@article{osti_20885779,
title = {A model of coal particle drying in fluidized bed combustion reactor},
author = {Komatina, M. and Manovic, V. and Saljnikov, A.},
abstractNote = {Experimental and theoretical investigation on drying of a single coal particle in fluidized bed combustor is presented. Coal particle drying was considered via the moist shrinking core mechanism. The results of the drying test runs of low-rank Serbian coals were used for experimental verification of the model. The temperature of the coal particle center was measured, assuming that drying was completed when the temperature equalled 100{sup o}C. The influence of different parameters (thermal conductivity and specific heat capacity of coal, fluidized bed temperature, moisture content and superheating of steam) on drying time and temperature profile within the coal particle was analyzed by a parametric analysis. The experimentally obtained results confirmed that the moist shrinking core mechanism can be applied for the mathematical description of a coal particle drying, while dependence between drying time and coal particle radius, a square law relationship, implicates heat transfer control of the process and confirms the validity of assumptions used in modeling.},
doi = {10.1080/00908310600688796},
journal = {Energy Sources, Part A: Recovery, Utilization, and Environmental Effects},
number = 3,
volume = 29,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
-
In the second part, the model is applied to the study of an atmospheric fluidized-bed coal combustor. Case studies are investigated to show the effects of a number of parameters. Proper representation of the grid region and use of actual feed distributions are shown to be essential to the prediction of combustor performance. Better particle elutriation and single-particle combustion sub-models are found to be key requirements for improved combustor modelling.
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