Combustion characteristics of low-rank coal chars in O2/CO2, O2/N2 and O2/Ar by TGA

SHEN Guo-dong; WANG Zhi-qi; WU Jing-li; HE Tao; LI Jian-qing; YANG Jing; WU Jin-hu

Volume 44 Issue 9

Sep. 2016

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Article Navigation > Journal of Fuel Chemistry and Technology > 2016 > 44(9): 1066-1073

SHEN Guo-dong, WANG Zhi-qi, WU Jing-li, HE Tao, LI Jian-qing, YANG Jing, WU Jin-hu. Combustion characteristics of low-rank coal chars in O2/CO2, O2/N2 and O2/Ar by TGA[J]. Journal of Fuel Chemistry and Technology, 2016, 44(9): 1066-1073.

Citation:

SHEN Guo-dong, WANG Zhi-qi, WU Jing-li, HE Tao, LI Jian-qing, YANG Jing, WU Jin-hu. Combustion characteristics of low-rank coal chars in O₂/CO₂, O₂/N₂ and O₂/Ar by TGA[J]. Journal of Fuel Chemistry and Technology, 2016, 44(9): 1066-1073.

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Combustion characteristics of low-rank coal chars in O₂/CO₂, O₂/N₂ and O₂/Ar by TGA

1.
Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
2.
University of Chinese Academy of Sciences, Beijing 100049, China

Funds:

Strategic Pilot Scientific & Technological Project of Chinese Academy of Sciences XDA0705100

More Information

Corresponding author: WANG Zhi-qi, Tel: 0532-80662764, E-mail: wangzq@qibebt.ac.cn
Received Date: 2016-04-07
Rev Recd Date: 2016-06-24

Available Online: 2021-01-23

Publish Date: 2016-09-10

Abstract

Abstract

The combustion reactivity of two chars prepared from two low-rank coals in Northwest China were studied using a thermogravimetric analyzer (TGA). The effects of different atmospheres (O₂/CO₂, O₂/N₂ and O₂/Ar) and different oxygen concentrations on the combustion characteristics were investigated. The results indicate that both atmosphere and oxygen concentration show effectiveness on combustion of char. Compared with N₂ and Ar, CO₂ could significantly promote the reaction. When combustion atmosphere changes from O₂/CO₂ to O₂/Ar, the burnout temperature increases by 63.7 and 68.8℃ for the two chars respectively. Meanwhile, when the combustion atmosphere changes from O₂/CO₂ to O₂/N₂, that is 135.9 and 129.6℃, respectively. An increase in concentration of oxygen can also improve the combustion performance of chars in the test. At the same time, kinetic analysis of the combustion profiles of the chars reveals that both the apparent activation energy E and the pre-exponential factor A increased with increasing oxygen concentration and the compensation effect exists between activation energy E and pre-exponential factor A of chars' combustion.
- low-rank coal char,
- combustion characteristic,
- thermogravimetric analysis,
- O₂/N₂, O₂/CO₂ and O₂/Ar atmosphere,
- different oxygen concentration,
- kinetics analysis

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References(34)

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