低NO_x切向燃煤锅炉炉膛配风模拟

Simulation on Air-Fuel Distribution in Low NO_x Tangential Firing Boilers

为优化低NO_x切向燃烧锅炉炉内风粉分布,建立了切向燃烧锅炉炉内风粉分布的监测模型,得到炉膛主燃烧区和燃尽区等局部区域过剩空气系数与风箱-炉膛出口差压、二次风挡板开度以及磨煤机风煤流量等参数的关系;基于该模型,开发了炉膛风粉分配模拟系统,对一台实际运行锅炉的风粉分布状态进行了改进模拟,结果表明,改进后的配风方式有利于减少送风机电耗,提高煤粉的燃尽度。

To optimize the air-fuel distribution in the furnace of low NOx tangential firing boilers, the model for monitoring the furnace air and fuel distribution is established, in which the relationships are obtained between the local excess air coefficients in the primary combustion or the separated over fire air （SOFA） zones and the wind box-furnace outlet pressure discrepancy, the secondary air baffle opening, as well as the mill air-fuel flow and other parameters. Based on the model, a simulation system for the furnace fuel and air distribution is developed to improve the air-fuel distribution of a practical operating boiler. The results show that the improved air and fuel distribution is helpful to reduce the energy consumption of the forced draft fan and improve the coal powder burnout.