Effect of heating rate on migration and transformation of N during pyrolysis of Shengli brown coal

ZHANG Shu; BAI Yan-ping; MI Liang; ZHENG Pan-pan; CHEN Xu-jun; XU De-ping; WANG Yong-gang

Volume 41 Issue 10

Oct. 2013

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Article Navigation > Journal of Fuel Chemistry and Technology > 2013 > 41(10): 1153-1159

ZHANG Shu, BAI Yan-ping, MI Liang, ZHENG Pan-pan, CHEN Xu-jun, XU De-ping, WANG Yong-gang. Effect of heating rate on migration and transformation of N during pyrolysis of Shengli brown coal[J]. Journal of Fuel Chemistry and Technology, 2013, 41(10): 1153-1159.

Citation:

ZHANG Shu, BAI Yan-ping, MI Liang, ZHENG Pan-pan, CHEN Xu-jun, XU De-ping, WANG Yong-gang. Effect of heating rate on migration and transformation of N during pyrolysis of Shengli brown coal[J]. Journal of Fuel Chemistry and Technology, 2013, 41(10): 1153-1159.

Citation:

ZHANG Shu, BAI Yan-ping, MI Liang, ZHENG Pan-pan, CHEN Xu-jun, XU De-ping, WANG Yong-gang. Effect of heating rate on migration and transformation of N during pyrolysis of Shengli brown coal[J]. Journal of Fuel Chemistry and Technology, 2013, 41(10): 1153-1159.

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Effect of heating rate on migration and transformation of N during pyrolysis of Shengli brown coal

1.
School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China;
2.
Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China

Received Date: 2013-01-28
Rev Recd Date: 2013-04-26
Publish Date: 2013-10-30

Abstract

Abstract

The effects of heating rate on migration, transformation and occurring forms of nitrogen during pyrolysis of Shengli brown coals were studied in a fixed-bed/fluidised-bed quartz reactor. The results indicate that the yields of NH₃ and HCN from the fast pyrolysis were much higher than those from the slow pyrolysis. The difference in the yields of NH₃ and HCN between the fast and slow heating rates increases with the increasing pyrolysis temperature. The maximum productions of NH₃ and HCN mostly occur at 973K, which is attributed to the enhanced condensation and secondary reactions with the increasing pyrolysis temperature. The release rate of char-N is faster than the weight loss rate of char itself at fast heating rate. The results from X-ray photoelectron spectroscopy (XPS) analysis imply that the pyrolysis process has facilitated the transformation of pyrrolic (N-5) to quaternary type nitrogen (N-Q) and pyridinic (N-6). It seems that the fast heating rate favors the formation of N-6 while the content of N-Q in char is relatively high at the slow heating rate.
- brown coal,
- pyrolysis,
- heating rate,
- nitrogen transformation

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References(32)

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