Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities
Volatile-char interactions are an important consideration in the design and operation of a gasifier. This study aims to investigate the effects of volatile-char interactions on the in situ char–steam reactivity at 800 °C and the ex-situ char–O2 reactivity at 400 °C. A Victorian brown coal was gasifi...
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| Format: | Journal Article |
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Elsevier Science Ltd
2011
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| Online Access: | http://hdl.handle.net/20.500.11937/32417 |
| _version_ | 1848753657681543168 |
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| author | Zhang, Shu Hayashi, J. Li, Chun-Zhu |
| author_facet | Zhang, Shu Hayashi, J. Li, Chun-Zhu |
| author_sort | Zhang, Shu |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Volatile-char interactions are an important consideration in the design and operation of a gasifier. This study aims to investigate the effects of volatile-char interactions on the in situ char–steam reactivity at 800 °C and the ex-situ char–O2 reactivity at 400 °C. A Victorian brown coal was gasified in 15% steam at 800 °C in a one-stage novel fluidised-bed/fixed-bed quartz reactor, in which the extent of volatile-char interactions could be controlled. The chars after varying extents of volatile-char interactions and/or varying extents of char conversion in steam were also collected for the measurement of their reactivity with air at 400 °C in a thermogravimetric analyser. Our results show that the char–steam gasification reactions were greatly inhibited by the volatile-char interactions. It is believed that the H radicals generated from the thermal cracking/reforming of volatiles slowed the char gasification in three ways: occupying the char reactive sites, causing the char structure to re-arrange/condense and enhancing the release of catalytic species inherently present in the brown coal. The importance of volatile-char interactions to char–steam reactivity was further confirmed by the char–air reactivity. |
| first_indexed | 2025-11-14T08:28:00Z |
| format | Journal Article |
| id | curtin-20.500.11937-32417 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:28:00Z |
| publishDate | 2011 |
| publisher | Elsevier Science Ltd |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-324172017-09-13T15:24:21Z Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities Zhang, Shu Hayashi, J. Li, Chun-Zhu Volatile-char interactions are an important consideration in the design and operation of a gasifier. This study aims to investigate the effects of volatile-char interactions on the in situ char–steam reactivity at 800 °C and the ex-situ char–O2 reactivity at 400 °C. A Victorian brown coal was gasified in 15% steam at 800 °C in a one-stage novel fluidised-bed/fixed-bed quartz reactor, in which the extent of volatile-char interactions could be controlled. The chars after varying extents of volatile-char interactions and/or varying extents of char conversion in steam were also collected for the measurement of their reactivity with air at 400 °C in a thermogravimetric analyser. Our results show that the char–steam gasification reactions were greatly inhibited by the volatile-char interactions. It is believed that the H radicals generated from the thermal cracking/reforming of volatiles slowed the char gasification in three ways: occupying the char reactive sites, causing the char structure to re-arrange/condense and enhancing the release of catalytic species inherently present in the brown coal. The importance of volatile-char interactions to char–steam reactivity was further confirmed by the char–air reactivity. 2011 Journal Article http://hdl.handle.net/20.500.11937/32417 10.1016/j.fuel.2010.11.008 Elsevier Science Ltd restricted |
| spellingShingle | Zhang, Shu Hayashi, J. Li, Chun-Zhu Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities |
| title | Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities |
| title_full | Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities |
| title_fullStr | Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities |
| title_full_unstemmed | Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities |
| title_short | Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal. Part IX. Effects of volatile-char interactions on char–H2O and char–O2 reactivities |
| title_sort | volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of victorian brown coal. part ix. effects of volatile-char interactions on char–h2o and char–o2 reactivities |
| url | http://hdl.handle.net/20.500.11937/32417 |