Morphology and structure evolution of flaky char particles during CO<sub>2</sub> gasification

MENG De-xi; ZHANG Ke-yi; DU Hao-yu; XU Jian-liang; CHEN Xue-li

Volume 46 Issue 7

Jul. 2018

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Article Navigation > Journal of Fuel Chemistry and Technology > 2018 > 46(7): 787-795

MENG De-xi, ZHANG Ke-yi, DU Hao-yu, XU Jian-liang, CHEN Xue-li. Morphology and structure evolution of flaky char particles during CO2 gasification[J]. Journal of Fuel Chemistry and Technology, 2018, 46(7): 787-795.

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MENG De-xi, ZHANG Ke-yi, DU Hao-yu, XU Jian-liang, CHEN Xue-li. Morphology and structure evolution of flaky char particles during CO₂ gasification[J]. Journal of Fuel Chemistry and Technology, 2018, 46(7): 787-795.

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Morphology and structure evolution of flaky char particles during CO₂ gasification

Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, Shanghai Engineering Research Center of Coal Gasification, East China University of Science & Technology, Shanghai 200237, China

Funds:

the National Key Research and Development Project 2016YFB060040202

More Information

Corresponding author: CHEN Xue-li, E-mail:cxl@ecust.edu.cn
Received Date: 2018-02-12
Rev Recd Date: 2018-04-29

Available Online: 2021-01-23

Publish Date: 2018-07-10

Abstract

Abstract

High temperature stage microscope was applied to observe morphology evolution of flaky char particles during gasification. Raman spectroscopy was used to analyze crystalline structures of gasification semicoke. Effect of gasification temperature (1000-1200℃) and initial equivalent diameter (1.00-1.60 mm) on morphology and structure evolution were examined. The results show that particle shrinkage in later stage of gasification is more intense than that in early stage. Within tested gasification temperature, the particle ASR (area shrinkage ratio) and VSR (volumetric shrinkage ratio) decrease with increasing temperature. The initial particle size of char has a significant effect on particle shrinkage. At 1100℃ the shrinkage trend of particle marks a turning point at initial diameter of 1.30 mm. The variation of char apparent density is dominated by carbon consumption. When the carbon conversion reaches 80%, the apparent density ratio linearly decreases below 0.4. At the same gasification temperature, with increasing carbon conversion the graphitization of char reduces first and then increases, while the amorphous carbon is opposite.
- flaky char,
- CO₂ gasification,
- morphology and structure evolution,
- high temperature stage microscope,
- Raman spectroscopy

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References(27)

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