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http://dx.doi.org/10.15231/jksc.2017.22.4.019

Deriving the Rate Constants of Coal Char-CO2 Gasification using Pressurized Drop Tube Furnace  

Sohn, Geun (School of Mechanical Engineering, Sungkyunkwan University)
Ye, Insoo (School of Mechanical Engineering, Sungkyunkwan University)
Ra, Howon (Clean Fuel Department, Korea Institute of Energy Reasearch)
Yoon, Sungmin (Clean Fuel Department, Korea Institute of Energy Reasearch)
Ryu, Changkook (School of Mechanical Engineering, Sungkyunkwan University)
Publication Information
Journal of the Korean Society of Combustion / v.22, no.4, 2017 , pp. 19-26 More about this Journal
Abstract
This study investigates the gasification of coal char by $CO_2$ under high pressures in a drop tube furnace(DTF). The rate constants are derived for the shrinking core model using the conventional method based on the set reactor conditions. The computational fluid dynamic(CFD) simulations adopting the rate constants revealed that the carbon conversion was much slower than the experimental results, especially under high temperature and high partial pressure of reactants. Three reasons were identified for the discrepancy: i) shorter reaction time because of the entry region for heating, ii) lower particle temperature by the endothermic reaction, and iii) lower partial pressure of $CO_2$ by its consumption. Therefore, the rate constants were corrected based on the actual reaction conditions of the char. The CFD results updated using the corrected rate constants well matched with the measured values. Such correction of reaction conditions in a DTF is essential in deriving rate constants for any char conversion models by $H_2O$ and $O_2$ as well as $CO_2$.
Keywords
Carbon conversion; Char; Coal gasification; Shrinking core model;
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Times Cited By KSCI : 2  (Citation Analysis)
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