动力工程学报
動力工程學報
동력공정학보
JOURNAL OF POWER ENGINEERING
2012年
11期
825-829,858
,共6页
段二朋%孙保民%郭永红%白涛%信晶
段二朋%孫保民%郭永紅%白濤%信晶
단이붕%손보민%곽영홍%백도%신정
超临界锅炉%低NOx改造%配风方式%氮氧化物%燃尽风%数值模拟
超臨界鍋爐%低NOx改造%配風方式%氮氧化物%燃儘風%數值模擬
초림계과로%저NOx개조%배풍방식%담양화물%연진풍%수치모의
supercritical boiler low NOx retrofit air distribution mode NOx%over-fire air numericalsimulation
针对某800MW超临界锅炉NOx排放量较高的问题,设计了配风方式不同的3种工况.利用CFD软件,对3种工况进行了炉内燃烧、传热及污染物排放等方面的数值计算,并分析了炉内的温度、NOx及cO组分的分布情况.结果表明:计算结果与实测数据吻合较好,空气分级燃烧使主燃区温度降低,CO体积分数升高,N0x质量浓度明显降低;燃尽风对燃料的燃尽率和炉膛出口烟温产生了不利影响,从而影响机组的经济性和安全性.通过对各个工况燃料的燃尽率及炉膛出口烟温进行综合比较分析,得出工况3为较理想的改造方案.
針對某800MW超臨界鍋爐NOx排放量較高的問題,設計瞭配風方式不同的3種工況.利用CFD軟件,對3種工況進行瞭爐內燃燒、傳熱及汙染物排放等方麵的數值計算,併分析瞭爐內的溫度、NOx及cO組分的分佈情況.結果錶明:計算結果與實測數據吻閤較好,空氣分級燃燒使主燃區溫度降低,CO體積分數升高,N0x質量濃度明顯降低;燃儘風對燃料的燃儘率和爐膛齣口煙溫產生瞭不利影響,從而影響機組的經濟性和安全性.通過對各箇工況燃料的燃儘率及爐膛齣口煙溫進行綜閤比較分析,得齣工況3為較理想的改造方案.
침대모800MW초림계과로NOx배방량교고적문제,설계료배풍방식불동적3충공황.이용CFD연건,대3충공황진행료로내연소、전열급오염물배방등방면적수치계산,병분석료로내적온도、NOx급cO조분적분포정황.결과표명:계산결과여실측수거문합교호,공기분급연소사주연구온도강저,CO체적분수승고,N0x질량농도명현강저;연진풍대연료적연진솔화로당출구연온산생료불리영향,종이영향궤조적경제성화안전성.통과대각개공황연료적연진솔급로당출구연온진행종합비교분석,득출공황3위교이상적개조방안.
According to the problem of high NOx emission existing in an 800 MW supercritical boiler, retro fit schemes with three air distribution modes were designed, based on which the infurnace combustion, heat transfer and NOx emission were numerically simulated using CFD method, while the temperature field, NOx concentration distribution and CO concentration distribution analyzed. Results show that the calculated results agree well with actual measurements. In the modes of stagedair combustion, the tem perature reduces in primary combustion zone, where the CO concentration rises and the NO, emission drops significantly. Overfire air may have unfavorable influence on the burnoff rate and outlet gas tem perature, which will reduce the security and efficiency of the unit. The results of comprehensive compari son and analysis on the burnoff rate and outlet gas temperature prove the retrofit scheme with air distribu tion mode three to be the most optimal one.