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Title: Modeling of multiphase flow and heat transfer in radiant syngas cooler of an entrained-flow coal gasification

Abstract

A comprehensive model has been developed to analyze the multiphase flow and heat transfer in the radiant syngas cooler (RSC) of an industrial-scale entrained-flow coal gasification. The three-dimensional multiphase flow field and temperature field were reconstructed. The realizable {kappa}-{epsilon} turbulence model is applied to calculate the gas flow field, while the discrete random walk model is applied to trace the particles, and the interaction between the gas and the particle is considered using a two-way coupling model. The radiative properties of syngas mixture are calculated by weighted-sum-of-gray-gases model (WSGGM). The Ranz-Marshall correlation for the Nusselt number is used to account for convection heat transfer between the gas phase and the particles. The discrete ordinate model is applied to model the radiative heat transfer, and the effect of ash/slag particles on radiative heat transfer is considered. The model was successfully validated by comparison with the industrial plant measurement data, which demonstrated the ability of the model to optimize the design. The results show that a torch shape inlet jet was formed in the RSC, and its length increased with the diameter of the central channel. The recirculation zones appeared around the inlet jet, top, and bottom of the RSC. The overallmore » temperature decreased with the heat-transfer surface area of the fins. The concentration distribution, velocity distribution, residence time distribution, and temperature distribution of particles with different diameters have been discussed. Finally, the slag/ash particles size distribution and temperature profile at the bottom of the RSC have been presented.« less

Authors:
; ; ; ;  [1]
  1. East China University of Science & Technology, Shanghai (China)
Publication Date:
OSTI Identifier:
21261648
Resource Type:
Journal Article
Resource Relation:
Journal Name: Industrial and Engineering Chemistry Research; Journal Volume: 48; Journal Issue: 22
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; MULTIPHASE FLOW; HEAT TRANSFER; SYNTHESIS GAS; COAL GASIFICATION; COOLING; HEAT EXCHANGERS; THREE-DIMENSIONAL CALCULATIONS; MATHEMATICAL MODELS; PARTICLES; RADIANT HEAT TRANSFER; ASHES; SLAGS; ENTRAINMENT

Citation Formats

Yu, G.S., Ni, J.J., Liang, Q.F., Guo, Q.H., and Zhou, Z.J. Modeling of multiphase flow and heat transfer in radiant syngas cooler of an entrained-flow coal gasification. United States: N. p., 2009. Web. doi:10.1021/ie901203d.
Yu, G.S., Ni, J.J., Liang, Q.F., Guo, Q.H., & Zhou, Z.J. Modeling of multiphase flow and heat transfer in radiant syngas cooler of an entrained-flow coal gasification. United States. doi:10.1021/ie901203d.
Yu, G.S., Ni, J.J., Liang, Q.F., Guo, Q.H., and Zhou, Z.J. Sun . "Modeling of multiphase flow and heat transfer in radiant syngas cooler of an entrained-flow coal gasification". United States. doi:10.1021/ie901203d.
@article{osti_21261648,
title = {Modeling of multiphase flow and heat transfer in radiant syngas cooler of an entrained-flow coal gasification},
author = {Yu, G.S. and Ni, J.J. and Liang, Q.F. and Guo, Q.H. and Zhou, Z.J.},
abstractNote = {A comprehensive model has been developed to analyze the multiphase flow and heat transfer in the radiant syngas cooler (RSC) of an industrial-scale entrained-flow coal gasification. The three-dimensional multiphase flow field and temperature field were reconstructed. The realizable {kappa}-{epsilon} turbulence model is applied to calculate the gas flow field, while the discrete random walk model is applied to trace the particles, and the interaction between the gas and the particle is considered using a two-way coupling model. The radiative properties of syngas mixture are calculated by weighted-sum-of-gray-gases model (WSGGM). The Ranz-Marshall correlation for the Nusselt number is used to account for convection heat transfer between the gas phase and the particles. The discrete ordinate model is applied to model the radiative heat transfer, and the effect of ash/slag particles on radiative heat transfer is considered. The model was successfully validated by comparison with the industrial plant measurement data, which demonstrated the ability of the model to optimize the design. The results show that a torch shape inlet jet was formed in the RSC, and its length increased with the diameter of the central channel. The recirculation zones appeared around the inlet jet, top, and bottom of the RSC. The overall temperature decreased with the heat-transfer surface area of the fins. The concentration distribution, velocity distribution, residence time distribution, and temperature distribution of particles with different diameters have been discussed. Finally, the slag/ash particles size distribution and temperature profile at the bottom of the RSC have been presented.},
doi = {10.1021/ie901203d},
journal = {Industrial and Engineering Chemistry Research},
number = 22,
volume = 48,
place = {United States},
year = {Sun Nov 15 00:00:00 EST 2009},
month = {Sun Nov 15 00:00:00 EST 2009}
}
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