为实现空气分级低NOx燃烧锅炉主燃烧区过剩空气系数的在线监控，提高该类燃烧系统的运行水平，以二次风挡板作为一次元件，利用二次风箱到炉膛出口的压降模型对二次风喷嘴的空气流量进行测量；在此基础上，根据锅炉冷热态试验数据，综合考虑颗粒燃烬、NOx排放量以及风机输送电耗等因素，建立空气分级低NOx燃烧锅炉炉内风粉分布的优化模型，在给定燃料喷嘴运行方式和炉膛出口过剩空气系数的条件下，对二次风挡板开度进行优化。一台300 MW锅炉的应用表明，炉膛配风优化后，烟气NOx排放和颗粒燃尽度得到良好协调，且在保证NOx排放量为255 mg/m3的情况下，优化后风箱-炉膛差压降低191 Pa，减少了风机电耗。

In order to achieve on-line measurement of the primary zone stoichiometric ratio in air staging combustion,and improve the operation of the low NOx combustion system,the pressure drop between wind-box and furnace outlet are modeled to measure the nozzle air flows with air baffles as primary components.On this basis,the combustion optimization model of the tangentially fired furnace with air staging is established to coordinate the particle burnout, NOx emission and fan power consumption by utilization of test data in both cold and hot state of the boiler,and the optimal openings of the airflow dampers are optimized under given operating mode of fuel nozzles and stoichiometric ratio in furnace outlet.The application in a 300 MW boiler shows that NOx emissions and particles burnout are well coordinated,and the differential pressure between the wind-box and the furnace outlet is significantly reduced to 191 Pa when the NOx emissions maintain at 255 mg/m3.

TK227.1