超临界锅炉烟温与汽温偏差热力计算与试验研究

Thermal calculation and experimental studies on flue gas and steam temperature deviation of supercritical boiler

针对大型电站超临界锅炉烟温与汽温偏差问题,结合国内首台600 MW超临界W型锅炉,重点研究不同负荷下汽水分离器出口汽温偏差,以及尾部受热面汽温偏差变化规律,并从优化汽温偏差出发,首次提出汽水分离器出口管道交叉布置结构,从而改变汽水流动方向,并结合锅炉热力计算,验证交叉布置结构减少汽温偏差的效果:当采用汽水分离器出口交叉布置结构后,屏式过热器入口左、右侧汽温偏差减小到原汽温偏差的1/2左右。

To solve the problems of flue gas and steam temperature deviation of supercritical boiler,the temperature deviation of the steam separator and the following heating surface are investigated in the domestic first 600 MW supercritical W-shaped flame boiler. Moreover,a special outlet cross layout structure of steam separator is designed and the role of the special outlet cross structure is investigated by thermal calculation. The results indicate that the steam temperature deviation of supercritical boiler is increased with the the flue gas temperature deviation and the growth of the following heating surface during actual operation.Meanwhile,the special outlet cross layout structure of steam separator has a remarkable effect on decreasing the steam temperature deviation,which has been reduced to half of the original level. Therefore,the special outlet cross layout structure of supercritical boiler steam separator is worthwhile to distinctly decrease the steam temperature deviation and increase the safe in operation of supercritical boil.