风率分配对660 MW机组褐煤锅炉煤粉燃烧性能影响的数值研究  

Numerical investigation on effects of air distribution ratio on coal combustion performance in a 660 MW lignite-fired boiler

作　　者：刁保圣 彭彬彬 李子祥 王亚军 陈臻 DIAO Baosheng;PENG Binbin;LI Zixiang;WANG Yajun;CHEN Zhen(Taizhou Power Generation Co.,Ltd.,CHN ENERGY Investment Group,Taizhou 225327,China;East China Electric Power Design Institute Co.,Ltd.,China Power Engineering Consulting(Group)Corporation,Shanghai 200063,China;School of Mechanical and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]国家能源集团泰州发电有限公司,江苏泰州225327 [2]中国电力工程顾问集团华东电力设计院有限公司,上海200063 [3]上海交通大学机械与动力工程学院,上海200240

出　　处：《热力发电》2023年第9期195-204,共10页Thermal Power Generation

摘　　要：以660 MW机组墙式切圆锅炉为对象,采用数值模拟方式研究了风率分配对煤粉锅炉炉内燃烧、受热面传热及NOx转化特性的影响规律。结果表明:在固定的燃尽风率下,一次风率的增大使得煤粉燃烧性能呈现先明显恶化而后有所改善的“V字型”变化趋势;一次风率升高将导致燃烧初期生成较多燃料型NOx,并导致炉膛出口NOx排放增大;燃尽风率不会改变燃烧性能随一次风率的变化规律,但其升高将导致煤粉燃烧性能显著恶化的临界一次风率下降;风率分配变化带来的一、二次风射流动量的变化是影响锅炉性能的主要因素,二者动量接近时将导致炉内燃烧性能显著恶化。据此,在锅炉实际运行中应尽量避免一次风率的大幅升高,若必须提高一次风率,则应适当降低燃尽风率来减轻一次风率升高后带来的锅炉性能的恶化。Taking a 660 MW wall-tangentially fired boiler as the research object,the effects of air distribution ratio on the characteristics of in-furnace coal combustion and heat transfer processes and NOx transformation were numerically investigated.Results show that under the fixed SOFA ratio,the increase of primary air ratio makes the overall boiler performance changes in V type that deteriorates evidently at first and then gets improved somewhat.The increased in primary air ratio leads to the generation of more fuel-NOx at the initial combustion stage,which thus increases the final NOx emission at the furnace exit.SOFA ratio does not change the variation trend of combustion performance along with the primary air ratio,but its increase leads to the decrease of the critical primary air ratio at which coal combustion performance deteriorates significantly.The variation of primary and secondary airflow momentums caused by the air distribution ratio is the main factor affecting the overall boiler performance,and coal combustion performance deteriorates significantly when their momentums are too close.Based on this,the large increase in the primary air ratio should be avoided during the practical boiler operation process.If it is inevitable,the SOFA ratio should be decreased to alleviate the deterioration of boiler performance caused by the increased primary air ratio.

关 键 词：燃尽风率 主燃区 一、二次风率 燃烧特性 褐煤锅炉 

分 类 号：TM621.2[电气工程—电力系统及自动化]