1000MW超超临界机组降压法蒸汽吹管

Intermittent pressure steam purging for 1 000 MW ultra-supercritical units

介绍邹县电厂四期工程2×1 000 MW超超临界锅炉在采用或不采用炉水循环泵时不熄火降压吹管的情况。吹管时发现无炉水循环泵时锅炉上部水冷壁存在短时干烧现象,此时应减少燃料量;在有炉水循环泵时增加给水流量达到吹管蒸发量后干烧现象消失。不熄火降压吹管时锅炉水冷壁水动力工况稳定,受热面管壁不超温,其成功经验可为类似锅炉吹管提供参考。

The details on the intermittent pressure cycle purging for 2 × 1 000 MW ultra-supercritical units with or without the boiler circulating pump in the fourth-stage project of Zouxian Power Plant are presented. It was observed that the upper water-wall dried out when the purge control valve was open for a boiler without the circulating pump, and such phenomenon disappeared when the feed-water flow rate equaled to the purging steam flow rate with help of the circulating pump. The fuel should also be reduced to the lowest degree as dry-out occurred. The practice shows that the hydrodynamic performance in the water-wall is stable and the tube wall temperature of the heating surface is normal during intermittent pressure cycle purging with flame.