O_2/N_2、O_2/CO_2和O_2/CO_2/NO气氛下煤粉燃烧NO_x排放特性

NO_x emission characteristics of pulverized coal combustion in O_2/N_2,O_2/CO_2 and O_2/CO_2/NO atmospheres

利用滴管炉研究了O2/N2、O2/CO2和O2/CO2/NO气氛下煤燃烧过程中NOx的排放特性。实验结果表明,在O2/N2和O2/CO2气氛下,高温或高O2浓度均使NO排放量增加。O2/CO2气氛下NO排放量比O2/N2气氛下NO排放量低大约30%-40%。在O2/CO2/NO气氛下,温度不同时,O2浓度变化对NO排放量的影响规律不同,对循环NO降解的影响规律也不同。高温不利于循环NO降解。随停留时间的延长NO排放量出现两个峰值。

NOx emission characteristics during pulverized coal combustion in O2/CO2, O2/N2 and O2/CO2/ NO atmospheres were studied by using a drop tube furnace. The results showed that in the O2/N2, atmosphere NO emission increased with the increase of O2 concentration or temperature. The same tendency of NOx emission was also found in the O2/CO2 atmosphere. However, the NOx emission in the O2/CO2 atmosphere was 30%- 40% lower than that in the O2/N2 atmosphere. In the O2/CO2/NO atmosphere, the effects of O2 concentration on NO,, emission as well as on recycled-NO reduction were different at different temperatures. High temperature did not favor recycled-NO reduction. There were two peak values of NOx emission with the increase of residence time.