煤炭解耦燃烧过程N迁移与转化Ⅲ:多组分气相化学反应实验

谢建军; 杨学民; 陈安合; 丁同利; 宋文立; 林伟刚

煤炭解耦燃烧过程N迁移与转化Ⅲ:多组分气相化学反应实验

1.
中国科学院过程工程研究所, 北京 100190;
2.
中国科学院研究生院, 北京 100049

基金项目: 国家自然科学基金(50576101)。

详细信息

通讯作者:
杨学民,Tel:010-82622893,Fax:010-82622893,E-mail:yangxm71@home.ipe.ac.cn。

中图分类号: TQ531
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出版历程
- 收稿日期: 2011-11-07
- 修回日期: 2012-02-27
- 刊出日期: 2012-10-31

Nitrogen transformation during coal decoulping combustion Ⅲ: NO and N₂O reduction with multi-component of pyrolysis gas

1.
Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
2.
Graduate University of Chinese Academy of Sciences, Beijing 100049, China

摘要

摘要: 在理想平推流反应器中进行了模拟热解气对模拟烟气中NO、N₂O的还原实验研究,考察了反应温度、过剩空气系数,模拟热解气中CH₄、CO、H₂、NH₃入口浓度与模拟烟气中NO、N₂O入口浓度对NO、N₂O与总氮转化率的影响。结果表明,向NH₃添加可燃气体CO、H₂、CH₄可使NO还原窗口向低温方向移动150~200 K,该温度窗口为1 073~1 223 K;但NH₃-CO-H₂-CH₄-O₂体系对NO、N₂O的还原分解作用依赖于体系的O₂浓度,仅在富燃料情形(过剩空气系数λ为0.6)下可分别达60.6%、100%的NO、N₂O脱除率;在反应温度1 073~1 223 K及过剩空气系数λ为0.6条件下,较高的热解气CH₄、CO、H₂浓度可增加NO排放,但有利于还原N₂O;增加NH₃入口浓度可增加NO分解率。
- 煤炭解耦燃烧 /
- NO /
- N₂O /
- 热解气 /
- NH₃
Abstract: Reduction of NO and N₂O with the simulated pyrolysis gas of NH₃-CO-H₂-CH₄-O₂ mixture was experimentally studied in an ideal plug flow reactor. The effects of temperature, excess air number λ, concentration of CH₄, CO, H₂, NH₃ in the simulated pyrolysis gas, concentration of NO and N₂O in the simulated flue gas on reduction of NO, N₂O and total nitrogen conversion efficiency were experimentally investigated. The results show that adding combustible or reducing species of CO, H₂, CH₄ into NH₃ can decease about 150~200 K of temperature range or window for reducing NO, the obtained optimal temperature range of reducing NO is in a range of 1 073~1 223 K. The excess air number λ or oxygen content in NH₃-CO-H₂-CH₄-O₂ mixture shows an important influence on reduction of NO and N₂O. When the excess air number λ is controlled as 0.6, i.e., similar to the case of fuel-rich, the maximum decomposition ratio of NO and N₂O in the simulated flue gas reaches 60.6% and 100%, respectively. When the excess air number λ is kept at 0.6 in a temperature range of 1 073~1 223 K, higher concentration of CH₄, CO, H₂ in the simulated pyrolysis gas can result in an effectively decomposition of N₂O, but lead to an increase of NO; however, higher conversion efficiency of NO can be achieved under the condition of increasing the concentration of NH₃ in the simulated pyrolysis gas.
- coal decoupling combustion /
- NO /
- N₂O /
- pyrolysis gas /
- NH₃

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参考文献(18)

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