氨再燃过程中NO还原及再生成机理

陈静怡; 杨卫娟; 史鹏聖; 朱晓宇; 何勇; 王智化

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中国环境科学 ›› 2024, Vol. 44 ›› Issue (6) : 3070-3077.

大气污染与控制

氨再燃过程中NO还原及再生成机理

陈静怡, 杨卫娟, 史鹏聖, 朱晓宇, 何勇, 王智化

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Mechanism of NO reduction and regeneration in ammonia reburning process

CHEN Jing-yi, YANG Wei-juan, SHI Peng-sheng, ZHU Xiao-yu, HE Yong, WANG Zhi-hua

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摘要

以氨再燃技术为应用背景,采用Chemkin软件选取Zhang机理在PFR反应器模型中进行NO/O₂/H₂O/N₂气氛下氨再燃的动力学模拟,考察了温度(1173~1573K)、氧浓度(0~4%)、再燃比(1%~30%)对再燃性能的影响.结果表明:在研究参数范围内,氨再燃脱硝效果显著,脱硝率可达97%以上,在1350~1469K温度窗口内能实现80%以上的脱硝率.并从反应路径角度对氨再燃过程中存在的NO还原区、平衡区、NO再生成区进行了分析.当氧浓度高于1.5%时,会出现NO再生成区,且氧浓度越高NO反弹越大最终NO浓度越高. 而再燃比的影响需要综合考虑脱硝率和未反应氨,在(10%±3%)范围内为佳.

Abstract

Aiming at the application background of ammonia reburning technology, the chemical reaction kinetics simulation of ammonia reburning was conducted under NO/O₂/H₂O/N₂ atmosphere in the PFR reactor model by using Chemkin software. The effects on reburning performance were investigated and revealed of temperature (1173~1573K), oxygen concentration (0~4%) and reburning ratio (1%~30%) by Zhang mechanism of ammonia reactions. The results showed that the denitration efficiency of ammonia reburning was remarkable in the range of the study range. The efficiencies could touch over 97% and it retained more than 80% in the temperature window of 1350~1469K. It was founded by an analyse from the perspective of reaction paths that the process of ammonia reburning comprised of the NO reduction region, equilibrium region and NO regeneration region. The NO regeneration region appeared visibly when the oxygen concentration was higher than 1.5%. Moverover the higher the oxygen concentration, the greater the rebound of NO and the higher the final NO concentration. The reburning ratio was preferable in the range of 10%±3% balancing between the denitration efficiency and the unreacted ammonia.

导出引用

陈静怡, 杨卫娟, 史鹏聖, 朱晓宇, 何勇, 王智化. 氨再燃过程中NO还原及再生成机理[J]. 中国环境科学. 2024, 44(6): 3070-3077

CHEN Jing-yi, YANG Wei-juan, SHI Peng-sheng, ZHU Xiao-yu, HE Yong, WANG Zhi-hua. Mechanism of NO reduction and regeneration in ammonia reburning process[J]. China Environmental Science. 2024, 44(6): 3070-3077

中图分类号： X511

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