660MW旋流对冲锅炉低NO_x燃烧优化数值模拟  

Numerical Simulation of the Optimization of the Low NO_x Combustion of a 660 MW Swirling Opposed-firing Boiler

作　　者：钟用禄 曾过房 李海山[1] 方庆艳[3] 

机构地区：[1]国网江西省电力科学研究院,江西南昌330096 [2]中电投新昌发电有限公司,江西南昌330088 [3]华中科技大学煤燃烧国家重点实验室,湖北武汉430074

出　　处：《热能动力工程》2015年第1期108-112,168,共5页Journal of Engineering for Thermal Energy and Power

摘　　要：对一台660 MW旋流对冲锅炉在不同层燃烧器组合运行工况下进行了炉内流动、燃烧和NOx排放特性的数值模拟,模拟结果与试验值相对误差小于10%。模拟结果表明:额定负荷时,5层燃烧器运行,停前墙和停后墙同层燃烧器时NOx排放和飞灰含碳量基本相同;停上层燃烧器相比于停中层燃烧器,空气分级效果强化,煤粉颗停留时间增加,NOx和飞灰含碳量分别降低9.5%和9.8%,在锅炉实际运行过程中,停上层燃烧器更有利于降低NOx排放和提高燃烧效率。A numerical simulation of the in-furnace flow,combustion and NOxemissions characteristics of a 660 MW swirling opposed-firing boiler was conducted to optimize its low NOxcombustion operating condition under the condition of burners in various layers operating in a combination mode. The relative error between the simulation results and the test values was less than 10%,indicating relatively good agreement. It has been found that at the rated load,when burners in all five layers are in operation,if the burners on the front and rear wall in the same layer are shut down respectively,the NOxemissions and the carbon content of flying ash are basically identical. When to shut down the burners in the upper layer is compared with to shut down the burners in the middle layer,the former has a better air staging effectiveness and a longer pulverized coal particle residence time and the NOxemissions and the carbon content of flying ash decrease by 9. 5% and 9. 8% respectively. In the practical operation of boilers,to shut down the burners in the upper layer will be favorable for reducing the NOxemissions and enhancing the combustion efficien-cy.

关 键 词：磨煤机组合 氮氧化物排放 燃烧 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]