轧钢加热炉采用低氮燃烧法降低NO_(x)排放的改造与实践

Reformation and practice of low nitrogen combustion method to reduce NO_(x) emission in steel rolling reheating furnace

新中型轧线建设项目热试发现两座加热炉排放烟气NO_(x)浓度超标,为保证NO_(x)达标排放,研究出低氮燃烧法,通过燃烧器控制燃烧初期NO_(x)的生成。采用空气分级来减少燃料氮转化为,NO_(x)同时通过快速响应自动调节空燃比的控制措施,进一步减少热力型NO_(x)生成。实践表明,改造方案解决了NO_(x)浓度超标这一问题,满足了国家和地方相关环保标准中热处理炉NO_(x)排放浓度≤150mg/m^(3)的要求。

In the hot test of the new and medium-sized rolling line construction project,it was found that the NO_(x)concentration of flue gas from two reheating furnaces exceeded the standard.In order to ensure the NO_(x)emission up to standard,a low nitrogen combustion method was developed,and the NO_(x)generation at the initial stage of combustion was controlled by burners.Air classification is adopted to reduce the conversion of fuel nitrogen into NOX,and the thermal NO_(x)generation is further reduced by the control measures of quick response and automatic adjustment of air-fuel ratio.Practice shows that transformation solves the problem of NO_(x)concentration exceeding the standard,and meets the requirement of NO_(x)emission concentration of heat treatment furnace≤150mg/m3 in national and local environmental protection standards.