200MW四角切圆燃烧锅炉改造工况数值模拟  

NUMERICAL SIMULATION OF COMBUSTION PROCESS IN A 200MW TANGENTIALLY FIRED FURNACE TO STUDY FURNACE RECONSTRUCTION

作　　者：潘维[1] 池作和[1] 斯东波[1] 阮涛[1] 岑可法[1] 

机构地区：[1]浙江大学热能工程研究所能源清洁利用与环境教育部重点实验室

出　　处：《中国电机工程学报》2005年第8期110-115,共6页Proceedings of the CSEE

基　　金：国家 863 专项经费项目(2002AA527053);国家重点基础研究发展规划项目(G1999022204-3)。~~

摘　　要：煤粉再燃是降低NOx排放的一项新技术。利用CFD软件平台,采用数值模拟方法对某电厂200MW 四角切圆燃烧锅炉改造前后炉内燃烧状况进行研究。改造方案1 采用空气分级,方案2 在1 基础上,增加细粉再燃。计算结果表明:改造后在最上面一层一次风喷口的高度区域,温度骤然下降,而CO 浓度很高,形成一个相对低氧,低温的还原性气氛区域。再燃降低NOx 48.9%左右。改造后煤粉燃尽率下降且燃尽所需时间也增加,降低了电厂的经济性。煤粉颗粒在炉内运动具有很大随机性,停留时间差异很大。平均而言,煤粉喷入高度越高,停留时间也越短。Coal reburning is a new technique to reduce nitrogen oxides (NOx) emission. Numerical simulation of combustion process in a 200 MW tangentially fired furnace is performed on CFD (Computational Fluid Dynamics)software platform. Air staging technique is applied in reconstruction project 1 and coal reburning is applied in project 2. Results show that after furnace reconstruction, at 5.26m furnace height, temperature drops to a low lever and so does oxygen concentration but carbon monoxide concentration is the highest. Deoxidization zone is formed. Micronized coal reburning can reduce NOx emission up to 48.9%. Coal burnout ratio reduces after reconstruction that decreases furnace economy. Coal particle movements in furnace are random. Averagely, particles residence time is longer if they are injected from a higher height position.

关 键 词：四角切圆燃烧 200MW 锅炉改造 CFD软件平台 工况 低NOX排放 数值模拟方法 还原性气氛 煤粉再燃 燃烧状况 空气分级 改造方案 计算结果 CO浓度 煤粉颗粒 时间差异 停留时间 一次风 燃尽率 经济性 随机性 炉内 电厂 高度 

分 类 号：TM621.2[电气工程—电力系统及自动化] TQ054[化学工程]