超临界600 MW机组CFB锅炉NOx排放分布特性实炉试验

Real tests on NOx emission distribution characteristics of a supercritical 600 MW CFB boiler

为了进一步研究循环流化床(CFB)锅炉NOx排放分布特性及变化规律,有针对性地进行设计优化、技术改造及运行调整等,本文在某台超临界600 MW机组CFB锅炉上进行了NOx排放分布特性实炉试验,得到了锅炉炉膛、分离器等部位NOx质量浓度的分布及变化规律,提供了炉内复杂气氛条件下NOx排放的基础数据,并提出了合理控制运行风量及给煤量,优化一、二次风配比,提高二次风口位置,以及采用烟气再循环和低过量空气系数运行等降低NOx原始排放质量浓度的技术措施,可为大型CFB锅炉设计、改进及运行等提供参考。

In order to further study the distribution characteristics and change law of NOx emission from circulating fluidized bed(CFB)boilers and carry out targeted design optimization,technical transformation and operation adjustment,real furnace test on a supercritical 600 MW CFB boiler was conducted.The distribution and change law of NOx concentration inside the furnace,separator and other parts of the boiler were obtained.The basis data of NOx emission in complex atmospheres inside the furnace were also gotten.Moreover,technical measures to reduce the NOx emission concentration were put forward,such as reasonably controlling the operating air volume and feed coal quantity,optimizing the ratio of the primary air to secondary air,raising the secondary air port,and employing the flue gas recirculation and low excessive air coefficient.It provides a good practical reference for the design,improvement and operation of large scale CFB boilers.