NOx release of char in constant temperature combustion under O2 / CO2 atmosphere
WANG Chunbo,YUE Shuang,XU Xubin,LI Yipeng
利用恒温热重-燃烧污染物在线测量系统,研究了O2/CO2气氛下,温度与反应气氛等对煤焦燃烧过程中NO与NO2释放规律的影响。结果表明:温度升高能显著缩短NOx析出时间,提高NO释放速度,降低NO2释放总量,并通过反应动力学参数的变化对该现象进行了解释;提高氧气浓度会导致NO瞬时释放量增加,同时有利于NO向NO2的氧化反应;水蒸气的存在造成CO2与H2O发生协同气化作用,导致煤焦燃烧过程因素更加复杂,一定浓度范围的水蒸气有助于促进NO与NO2的释放;空气气氛下NO瞬时释放量明显高于富氧气氛下,但NO2释放特性差别不大。
In order to study the NOx release characteristics of char under oxygen-enriched atmosphere,the effect of temperature and reaction atmosphere on the release characteristics of NO and NO2 during its combustion was tested by using a constant temperature thermogravimetry-combustion pollutant measurement system. The results showed that the release time was shorten for NOx ,the release rate of NO was increased and the release amount of NO2 was reduced by raising temperature in O2 / CO2 atmosphere. And the results explained and verified by the conversion rate and kinetic parameters of the reaction further. The instantaneous release amount of NO was raised with O2 concentration,and it al- so promoted the oxidation of NO to NO2 ;the addition of water vapor made CO2 and H2 O happen synergistic gasifica- tion,and it made the steam gasification more complex,some water vapor could help to stimulate the release of NO2 and NO;the instantaneous release amount of NO in air was higher than that in O2 / CO2 atmosphere,but the difference of re- lease characteristics of NO2 was a little.
O2 / CO2 ;release characteristics;NOx ;char;constant combustion
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会