空气分级燃烧对炉内NOx生成影响的数值模拟研究

现阶段国家对电厂污染物的排放标准制定越来越严格,电厂需降低NOx排放的幅度也越来越大,对烟气中NOx含量的控制将成为电厂今后控制污染物排放的重点。本文总结了现阶段比较常用的电站锅炉降低NOx排放的改造方法,针对电厂的实际情况,拟采用空气分级的方法,通过在主燃区的上部设置燃尽风来降低NOx排放。改造结果表明,降低主燃区内风量后,主燃区内氧量和温度水平有所下降,NOx在炉内的生成量明显降低。另外,由模拟结果可知,主燃区内氧量越低,愈有利于NOx的降低,但可能会造成飞灰含碳量的增大,燃烧效率的降低,这些都会影响电厂的经济性。在实际运行过程中,可通过提高煤粉细度、合理配风来调整。

Numerical Simulatiion Study of Staged Combustion Reducing NOx Emission

The stae constituted more rigorous to control the pollutant of power plant,and the power plant should reduce NOx emission much more,so controling NOx in the gas would be very important in pollutant control of the power plant in the furure.This paper analyzes the current commonly used methods of transformation of the furnace to reduce NOx and aims at the actual situatujion of power plant,adopts air classification method th reduce NOx emissions by arranging overfired air in the upper part of primary combustio...