天然气再燃过程与排放特性数值研究  

Numerical study of process and emissions characteristics of natural gas reburning

作　　者：毕明树[1] 贾艳艳[1] 李芳[1] 

机构地区：[1]大连理工大学化工学院,辽宁大连116012

出　　处：《大连理工大学学报》2009年第1期48-54,共7页Journal of Dalian University of Technology

摘　　要：应用CFD计算软件FLUENT6.1,对煤粉炉天然气再燃烧过程进行了数值模拟.分析了不同再燃烧工况下,NOx、CO2、CO等污染物的排放量及飞灰含碳量与煤粉炉热效率之间的关系.结果表明,天然气再燃技术能够有效地降低NOx的排放量,且燃料燃烧充分,煤粉炉热效率较高.给出了在保证煤粉炉较高热效率前提下,有效降低NOx排放的天然气再燃量、天然气投射位置以及再燃烧区过量空气系数.NOx排放浓度的计算值与试验值的变化趋势基本保持一致,表明计算方法可用于工程实际.对现有锅炉进行一定的结构改造,通过天然气再燃可达到高效降低NOx排放的目的.The numerical simulation with CFD software FLUENT6.1 on natural gas reburning in coal-powder furnace was conducted to study the relationship between pollutants （NOx, CO2 and CO） emissions, unburned carbon in fly ash （UBC） and heat efficiency of coal-powder furnace. The results indicate that natural gas reburning can effectively reduce NO2 emission while keeping fuel fully burning and high heat efficiency. The optimum range of natural gas fraction, injection location of reburning fuel and stoichiometric ratio in rich zone are proposed. The computational results are in good agreement with the experimental ones, which indicates that the numerical calculation method has practical value of application in engineering. It is suggested that through a certain extent reconstruction to boilers, the gas reburning technology can reach a low level of NO2 emission.

关 键 词：热能动力工程 天然气 再燃 NOX脱除 数值模拟 

分 类 号：TK121[动力工程及工程热物理—工程热物理]