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2011 | 32 | 2 | 155-169
Article title

Changes in total active centres on particle surfaces during coal pyrolysis, gasification and combustion

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Abstracts
EN
In the paper, on the basis of our studies and the available literature data, a model of changes in the number of active centers corresponding to the structure of the reactive coal particle has been developed. A new distribution function that links the specific surface area of a particle with its porosity and reaction degree has been proposed. An equation for estimation of changes in this parameter during the reaction, on the basis of the initial value, has been presented. In the range of our data and the analysis of the literature data, the model, with satisfactory accuracy, describes internal structural changes of coal and coal char particles. The present results may constitute a basis for complex modelling of coal conversion processes.Based on the results it was found that the total active centres are related to the internal surface area and porosity of the particle. For a specific coal type, this value depends on the porosity, true density and size of the particle. Changes in total active centres, when these structural properties during thermal conversion of coal are considered, are described in equations.
Keywords
Publisher

Year
Volume
32
Issue
2
Pages
155-169
Physical description
Dates
published
1 - 6 - 2011
online
11 - 7 - 2011
Contributors
  • Department of Metallurgy, Group of Process Energy, Silesian University of Technology, ul. Krasinskiego 8, 40-019 Katowice, Poland
author
  • Department of Metallurgy, Group of Process Energy, Silesian University of Technology, ul. Krasinskiego 8, 40-019 Katowice, Poland
  • Department of Metallurgy, Group of Process Energy, Silesian University of Technology, ul. Krasinskiego 8, 40-019 Katowice, Poland
References
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Document Type
Publication order reference
Identifiers
YADDA identifier
bwmeta1.element.-psjd-doi-10_2478_v10176-011-0012-8
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