天然气再燃降低NO_x的化学动力学及影响因素分析

Analysis on the kinetic mechanism and key parameters of NO_x reduction with natural gas reburning

对天然气再燃降低NOx(氮氧化物)的化学动力学及其主要影响因素进行了分析,描述了再燃区温度、停留时间、过量空气系数以及混合状况对降低NOx排放的影响,并对天然气再燃在我国电力行业的应用前景进行了预测.

Reburning is a process whereby a hydrocarbon fuel is injected immediately into the downstream combustion zone to establish a fuel-rich zone in order to convert NOx to N2. The kinetic mechanism of NOx reduction with natural gas reburning is analyzed. The key parameters influencing the reburn process are described. It has been found that to achieve a relatively high NOx reduction, proper values should be selected as regards the following parameters: temperature, residence time, stoichiometric ratio in reburning zone, as well as an optimal position of natural gas injection. It is predicted that there is a potential for wide application of natural gas reburning technology in coal-fired utility boilers in China.