Migration and transformation characteristics of zigzag char-N in lean oxygen environment

CHEN Ping; LI Ji-hua; GU Ming-yan; CHEN Guang

Volume 48 Issue 8

Aug. 2020

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CHEN Ping, LI Ji-hua, GU Ming-yan, CHEN Guang. Migration and transformation characteristics of zigzag char-N in lean oxygen environment[J]. Journal of Fuel Chemistry and Technology, 2020, 48(8): 920-928.

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CHEN Ping, LI Ji-hua, GU Ming-yan, CHEN Guang. Migration and transformation characteristics of zigzag char-N in lean oxygen environment[J]. Journal of Fuel Chemistry and Technology, 2020, 48(8): 920-928.

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Migration and transformation characteristics of zigzag char-N in lean oxygen environment

School of Energy and Environment, Anhui University of Technology, Maanshan 243002, China

Funds:

National Key Basic R & D Project of China 2017YFB0601805

ational Natural Science Foundation of China 51776001

Received Date: 2020-06-30
Rev Recd Date: 2020-07-24

Available Online: 2021-01-23

Publish Date: 2020-08-10

Abstract

Abstract

The migration and transformation of N in zigzag char-N with the presence of high concentration NO in the reduction zone is investigated by quantum chemistry method. Transformation characteristics of N in lean oxygen environment are systematically calculated from the molecular level by constructing a char-N model containing a hydroxyl group. The results show that NO in the reduction zone can combine with N in the char to form N₂; and the presence of oxygen enhances the char chemical activity and further promotes the release of N in the char. The co-existence of oxygen and NO in the reduction zone makes the release of N and the combustion of C occur simultaneously, which is manifested by NO and N in the char combining to form N₂, and at the same time oxygen and C in the char formation CO₂ or CO. The kinetic calculations of the rate-limiting step rate constants of the C combustion products show that C is easily oxidized to CO under low temperature and lean oxygen conditions, and with the temperature rise the CO₂ generation rate increases significantly and the high temperature is conducive to CO₂ formation.
- char-N,
- NO,
- hydroxyl group,
- CO,
- CO₂

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References(26)

References

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