Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions

It is known that Victorian brown coal has higher reactivity for gasification because of catalysis of inherent AAEMspecies than high-rank coal. However, the experimental results of steam gasification of brown coal in a fluidised-bed/fixed-bed reactor at 800 C have suggested that the inhibitory effect...

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Main Authors: kajitani, Shiro, Tay, Hui-ling, Zhang, Shu, Li, Chun-Zhu
Format: Journal Article
Published: Elsevier Science Ltd 2013
Subjects:
Online Access:http://hdl.handle.net/20.500.11937/44757
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author kajitani, Shiro
Tay, Hui-ling
Zhang, Shu
Li, Chun-Zhu
author_facet kajitani, Shiro
Tay, Hui-ling
Zhang, Shu
Li, Chun-Zhu
author_sort kajitani, Shiro
building Curtin Institutional Repository
collection Online Access
description It is known that Victorian brown coal has higher reactivity for gasification because of catalysis of inherent AAEMspecies than high-rank coal. However, the experimental results of steam gasification of brown coal in a fluidised-bed/fixed-bed reactor at 800 C have suggested that the inhibitory effects of the volatile–char interactions on char gasification are not negligible. The mechanisms and kinetics model of the char gasification and volatile–char interactions were discussed to describe quantitatively the inhibition of char gasification by volatiles, in this study. The elementary reactions of the char gasification and volatile–char interactions, which are consist of the adsorption of free radicals from volatiles, the volatilisation of catalyst and the evolution of char structure affected by radicals from volatiles, were proposed. The L-H type reaction rate equations for brown coal gasification were determined, and the kinetics model was verified by the comparison with several series of experiments. The proposed kinetics model described the experimental results of the coal conversions and the concentrations of Na in char during steam gasification very well. This kinetics model would be useful in designing any industrial fluidised-bed gasifier for low-rank fuels and estimating their performance.
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institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T09:22:36Z
publishDate 2013
publisher Elsevier Science Ltd
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spelling curtin-20.500.11937-447572017-02-28T01:37:39Z Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions kajitani, Shiro Tay, Hui-ling Zhang, Shu Li, Chun-Zhu Victorian brown coal Volatile–char interactions Kinetics Gasification It is known that Victorian brown coal has higher reactivity for gasification because of catalysis of inherent AAEMspecies than high-rank coal. However, the experimental results of steam gasification of brown coal in a fluidised-bed/fixed-bed reactor at 800 C have suggested that the inhibitory effects of the volatile–char interactions on char gasification are not negligible. The mechanisms and kinetics model of the char gasification and volatile–char interactions were discussed to describe quantitatively the inhibition of char gasification by volatiles, in this study. The elementary reactions of the char gasification and volatile–char interactions, which are consist of the adsorption of free radicals from volatiles, the volatilisation of catalyst and the evolution of char structure affected by radicals from volatiles, were proposed. The L-H type reaction rate equations for brown coal gasification were determined, and the kinetics model was verified by the comparison with several series of experiments. The proposed kinetics model described the experimental results of the coal conversions and the concentrations of Na in char during steam gasification very well. This kinetics model would be useful in designing any industrial fluidised-bed gasifier for low-rank fuels and estimating their performance. 2013 Journal Article http://hdl.handle.net/20.500.11937/44757 Elsevier Science Ltd restricted
spellingShingle Victorian brown coal
Volatile–char interactions
Kinetics
Gasification
kajitani, Shiro
Tay, Hui-ling
Zhang, Shu
Li, Chun-Zhu
Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions
title Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions
title_full Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions
title_fullStr Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions
title_full_unstemmed Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions
title_short Mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions
title_sort mechanisms and kinetic modelling of steam gasification of brown coal in the presence of volatile–char interactions
topic Victorian brown coal
Volatile–char interactions
Kinetics
Gasification
url http://hdl.handle.net/20.500.11937/44757