摘要
以某电厂3#660 MW超超临界二次再热机组锅炉为研究对象,针对锅炉冷灰斗高温腐蚀原因进行分析和调整。通过一次风速调平、降低一次风速、底层燃烧器二次风旋流强度、煤粉细度调整,冷灰斗区域壁面氛围中CO浓度和H2S浓度较调整前分别降低8000×10-6和140×10-6。优化调整可以改善高温腐蚀区域部分积粉问题,尤其对底层燃烧器和冷灰斗之间的水冷壁积粉问题改善明显,但无法从根本上解决底层燃烧器二次风量不足和冷灰斗区域高温腐蚀问题。提出通过在冷灰斗区域布置贴壁风口改善冷灰斗区域壁面氛围,降低冷灰斗高温腐蚀,底层燃烧器优化改造提高二次风量,改善一次风和二次风匹配性,延长二次风混入一次风时间,提高煤粉燃尽,减少煤粉沉积在冷灰斗区域。锅炉安全性得到提高,为同类型机组运行提供参考依据。
The cause of high temperature corrosion of cold ash hopper of boiler is analyzes and adjusted by taking the boiler of 3# 660 MW ultra-supercritical secondary reheating unit of a power plant as the research object. The primary air speed is leveled, the primary air speed is reduced, the secondary air swirl strength of the bottom burner is reduced, the fineness of the pulverized coal is adjusted, the concentration of CO and H2S in the wall surface atmosphere of cold ash hopper are reduced by 8000×10-6 and 140×10-6 respectively. The optimization and adjustment can improve the problem of the partial product of high-temperature corrosion area, especially the improvement of problem of water-cooled wall product powder between the bottom burner and the cold ash hopper, but it is not possible to fundamentally solve the problem of insufficient secondary air volume of bottom burner and the problem of high-temperature corrosion of the area of cold-hoppe. It is proposed that the wall atmosphere of the cold ash hopper area can be improved by arranging the wall tuyere in the cold ash hopper area, the high temperature corrosion problem of the cold ash hopper can be reduced, the secondary air volume can be improved, the matching between the primary air and the secondary air can be improved, the time of the secondary air mixing into the primary air can be prolonged, the pulverized coal will be burned out, and the pulverized coal deposition in the cold ash hopper area can be reduced. The safety of boiler has been improved, which provides a reference for the operation of the same type of unit.
作者
陈辉
戴维葆
蔡培
黄林滨
CHEN Hui;DAI Wei-bao;CAI Pei(Guodian Science And Technology Research Institute)
出处
《电站系统工程》
2021年第1期38-40,共3页
Power System Engineering
关键词
超超临界二次再热
冷灰斗
高温腐蚀
优化调整
ultra-supercritical secondary reheat unit
furnace hoppe
corrosion at high temperature
optimization adjustment
