煤热解挥发分还原NO的反应过程分析

ANALYSIS OF NO REDUCTION MECHANISM BY VOLATILES FROM COAL PYROLYSIS

采用详细的化学反应动力学机理对烟煤快速热解挥发分气体还原NO过程进行了数值模拟.根据实际反应条件确定模拟条件为0.1 MPa,1273～1573 K,煤质为准格尔烟煤。首先应用FG-DVC模型模拟得到了热解条件下的气体成分和含量,然后将该气体作为再燃燃料,选取化学当量比为0.6、1.0和1.2进行还原NO的计算.通过敏感性分析和生成速率分析,发现了控制NO生成和还原的关键步骤.只有CH_3、N_2O、NH_i、HCN和H_2CN才可以将NO还原成N_2。

The NO reduction by volatiles from bituminous coal pyrolysis was simulated by adopting detailed chemical kinetics mechanism.The reaction condition was determined under 0.1MPa and 1273-1573 K,and the coal is Zhunger bituminous coal.FG-DVC was first adopted to determine the composition and the contents of the volatiles from coal pyrolysis.Then NO reduction was simulated under the stoichiometric ratio of 0.6,1.0 and 1.2 respectively,by using the volatiles from the pyrolysis calculation.The key steps of NO formation and reduction were put forward by the analysis of sensitivity and the rate of production.The results also indicated that only CH3,N2O,NHi,HCN and H2CN enable to reduce NO to N2.