循环流化床锅炉水冷壁管束的磨损及预防

The Cause and Prevention of Erosion of Water-Cooled Wall of CFB Boiler

循环流化床燃烧技术是近二十年迅速发展起来的一种洁净煤燃烧技术。循环流化床锅炉具有煤种适应性强、燃烧效率高、污染物排放低和负荷调节性能好等优点,是目前推广应用的炉型之一。但是,由于炉内有大量的床料及循环物料,煤在物化状态下低温循环燃烧,造成烟气中含有大量的飞灰颗粒,这些灰粒高速冲刷水冷壁管、对流受热面等部位,使其壁面受到剧烈磨损,发生局部的严重破坏,甚至导致停炉事故。目前随着过热器和省煤器防护技术的成熟,磨损得到较好的控制,但是水冷壁管束的磨损控制还在摸索中。因此,了解飞灰磨损规律,找出主要磨损部位及原因,选择合理的防磨措施,进行合理的技术改造,保持锅炉最佳方式运行,使磨损损害减少到最小程度,无论从安全或经济上都是非常必要和及时的。

As a cleaning coal combustion technology, the Circulating Fluidized Bed（CFB） technology has been successfully used on boilers since 1980＇ s. The CFB boilers, characterized in good fuel flexibility, high combustion efficiency, low pollution and good capability of output, have been popularized all over the world. Material erosion of heating surface, because of mass circulating fluidized materials combusting at low temperature, is a very crucial problem of CFB boilers. The strive for being more reliable and economical has been the central line of the history of CFB combustion technology. The prevention of erosion of water-cooled wall is still in research while the erosion of other parts of heating surface is in controll.