1021 t/h四角切圆锅炉低NO_x燃烧器优化设计  

Optimal design of low NO_x burner in a 1021t/h tangentially-fired boiler and discharge

作　　者：吕太[1] 吴红峰 吴昱 王泽民[1] 

机构地区：[1]东北电力大学能源与动力工程学院,吉林吉林132012 [2]华电电力科学研究院,浙江杭州310030

出　　处：《兰州理工大学学报》2016年第2期62-67,共6页Journal of Lanzhou University of Technology

摘　　要：针对某电厂1021t/h四角切圆锅炉NO_x排放质量浓度高、炉内结渣严重的问题,提出基于多空气分级低氮燃烧技术的燃烧器改造方案,运用Fluent软件对改造前后炉内燃烧状况进行数值模拟,并利用试验优化运行参数.对比分析计算和试验结果表明:改造后煤粉气流对水冷壁冲刷减弱,结渣现象明显改善;炉内整体温度降低,最高温度下降80℃左右,有效抑制了热力型NO_x的生成;主燃区CO质量分数增大,炉内还原性气氛增强,很大程度抑制了燃料型NO_x的生成;改造后NO_x排放质量浓度降幅达47%左右,浓相一次风反切角度取值宜在15°左右.Aimed at the problems in a 1021t/h tangentially-fired boiler of a power plant such as high mass-concentration of NOxdischarging and serious slogging in boiler chamber,a reconstruction option of boiler burner was presented on the basis of combustion technique with multi-staged air jets and low nitrogen discharge.By using software Fluent,the combustion condition in boiler burner before and after reconstruction was numerically simulated and by means of experiment,the operational parameters were optimized.It was shown by comparing and analyzing both the computational and experimental results that after burner reconstruction,the washing of the pulverized coal flow against the water-cooling wall would be weakened and the phenomenon of slogging improved remarkably.The temperature in entire burner was decreased and the maximum temperature was dropped by about 80 ℃,restraining thermal-type NOxformation effectively.The mass-fraction of CO in main combustion zone was increased and the reduction atmosphere in the burner was enhanced,restraining the formation of fuel-type NOxto a great extent.The NOx discharging mass-concentration declined by about 47%.The reverse tangential angle of dense-phase primary air-jet should be chosen as about 15°.

关 键 词：锅炉燃烧 低NOX 空气分级 改造 数值模拟 

分 类 号：TK224.1[动力工程及工程热物理—动力机械及工程]