组合式一次风管对锅炉运行的影响分析  

Effects of Combined Type Primary Air Pipe on Operation Performance of the Boiler

作　　者：闫顺林[1] 韩韦[1] 王皓轩[1] 张永昇 刘洋[1] YAN Shunlin;HAN Wei;WANG Haoxuan;ZHANG Yongsheng;LIU Yang(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Baoding 071003,Hebei Province,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,河北保定071003

出　　处：《动力工程学报》2018年第9期695-705,共11页Journal of Chinese Society of Power Engineering

摘　　要：为了解决锅炉低负荷运行时一次风气流中煤粉浓度较低、燃烧不稳定的问题,提出了组合式一次风管的设计。运用Fluent数值模拟软件,采用煤粉燃烧综合模型和污染物排放模型,对某660 MW锅炉分别进行改造前后40%THA工况(THA表示额定工况)和30%THA工况的燃烧模拟和NO_x摩尔分数模拟。对比分析了采用组合式一次风管对锅炉空气动力场、着火稳燃情况和NOx摩尔分数的影响。结果表明:采用组合式一次风管时,只要燃烧器喷口改造合理,对空气动力场的影响较小;炉膛整体温度提高,特别是燃烧器区域,着火燃烧稳定性提高;大大降低锅炉低负荷运行时炉膛出口NO_x摩尔分数,提高了锅炉低负荷运行的安全性和经济性。To solve the problem of unstable combustion in low load operation of a boiler due to low concentration of pulverized coal,a retrofit scheme was put forward by adopting the design of combined type primary air pipe.Based on the comprehensive model of pulverized coal combustion and the model of pollutant emission,numerical simulations were conducted on the combustion status and NOx emission of a 660 MW boiler respectively under 40%THA and 30%THA condition before and after retrofit using Fluent software,so as to comparatively analyze the effects of combined type primary air pipe on the aerodynamic field,ignition condition and NOxemission of the boiler.Results show that when the combined primary air pipe is adopted,the aerodynamic field would be slightly influenced,as long as the nozzle of the burner is properly transformed;the overall temperature in the furnace,especially in the burner area,would be improved,resulting in increased combustion stability of the boiler;the NOx emission at furnace outlet would be reduced greatly in low load operation,in which case safety and economical operation would be obtained for the boiler.

关 键 词：组合式一次风管 稳燃 NOx 数值模拟 

分 类 号：TK227[动力工程及工程热物理—动力机械及工程]