Effect of operating conditions on release and transformation of sodium during CFB gasification of Zhundong coal

YANG Zi-jian; GUO Shuai; WANG Xiao-fang

doi:10.1016/S1872-5813(23)60348-2

Volume 51 Issue 9

Sep. 2023

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Article Navigation > Journal of Fuel Chemistry and Technology > 2023 > 51(9): 1232-1239

YANG Zi-jian, GUO Shuai, WANG Xiao-fang. Effect of operating conditions on release and transformation of sodium during CFB gasification of Zhundong coal[J]. Journal of Fuel Chemistry and Technology, 2023, 51(9): 1232-1239. doi: 10.1016/S1872-5813(23)60348-2

Citation:

YANG Zi-jian, GUO Shuai, WANG Xiao-fang. Effect of operating conditions on release and transformation of sodium during CFB gasification of Zhundong coal[J]. Journal of Fuel Chemistry and Technology, 2023, 51(9): 1232-1239. doi: 10.1016/S1872-5813(23)60348-2

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Effect of operating conditions on release and transformation of sodium during CFB gasification of Zhundong coal

doi: 10.1016/S1872-5813(23)60348-2

YANG Zi-jian^{1, 2, #
,},
GUO Shuai^{1, #
,
,},
WANG Xiao-fang^1
,

1.
Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
2.
China University of Petroleum (Beijing), Beijing 102249, China)

Funds: The project was supported by the National Natural Science Foundation of China (22008236)

More Information

Corresponding author: Tel/Fax: 13522312096, E-mail: guoshuai@iet.cn
Received Date: 2023-01-06
Accepted Date: 2023-02-03
Rev Recd Date: 2023-01-31

Available Online: 2023-03-14

Publish Date: 2023-09-30

Abstract

Abstract

To provide some useful suggestions to the operation of circulating fluidized bed (CFB) gasifier, the effect of gasification temperature, residence time and agent on the release and transformation of sodium was studied by using a fixed bed reactor combined with Factsage software. The results indicated that gasification temperature was the significant factor to the release and transformation of sodium. For the promoting effect of sodium release, it was ascribed to the intense of sodium volatilization and competitive reaction between lime and meta-kaolin. Meanwhile, the high temperature promoted the formation of nepheline and slag. The threshold temperature of latter was near 950 °C. It was interesting to find that the release of sodium could be divided into two stages: coal pyrolysis and char gasification. In coal pyrolysis, part of organic and water-soluble sodium was released. The remainder either combined with char structure, or reacted with minerals. In char gasification, Sodium, combined with char structure, was released along with char gasification. Due to the decrease of melting temperature and the formation of NaOH, steam showed a promoting effect on the sodium release. Oppositely, oxygen and nitrogen presented an inhibiting effect. The former was ascribed to the formation of Na₂SO₄, while the latter was caused by the chemical binding and physical wrapping effect of char.
- Zhundong coal,
- gasification,
- sodium,
- release and transformation

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References(24)

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