摘要
针对某亚临界600MW机组锅炉NOx排放量较高的问题,提出了沿炉膛高度垂直方向空气分级和主燃烧区域水平方向空气分级的复合空气分级改造方案。利用数值模拟软件Fluent,分析了不同分离燃尽风高度和间距对炉内燃烧温度、CO浓度及NOx排放量的影响。结果表明:数值模拟结果能够很好地反映炉内燃烧情况;空气分级燃烧使主燃烧区温度降低,炉膛出口温度升高,CO体积分数升高,NOx排放浓度明显降低;通过对4个模拟工况NOx排放、炉膛出口烟温及锅炉效率的对比分析,得出C2工况为最佳布置方式。
To solve the problem of high NOxemission in a 600 MW subcritical controlled circulation boiler,compound air staging technology retrofit schemes with vertical air staging along furnace height direction and horizontal air staging in main combustion zone were proposed.The numerical simulation software Fluent was employed to investigate the influence of SOFA elevation and spacing on combustion temperature,CO concentration and NOxemission.The results show that,the simulation results can well reflect the actual combustion situation.In the scheme of air staging combustion,the temperature of primary combustion zone reduced,while that at the furnace outlet increased.The CO concentration at the furnace outlet rose and the NOxemission decreased significantly.The results of comprehensive comparison and analysis on the NOxemission,furnace outlet gas temperature and boiler efficiency proved the C2 condition was be the optimum arrangement.
出处
《热力发电》
CAS
北大核心
2014年第8期120-124,130,共6页
Thermal Power Generation
