超超临界机组直流锅炉水冷壁节流孔圈结垢堵塞超温防范对策

锅炉水冷壁管因超温经常出现爆管的问题,为此,以引进日本三菱技术设计制造的超超临界机组为例,从其结构入手分析引起爆管的原因,指出直流锅炉水冷壁管因在设计上大量使用垂直节流孔圈,受孔圈结构特点、给水电位差及pH值等因素的影响,其附近容易产生结垢聚集,影响给水流量,降低了冷却效果,从而引起管壁超温,导致超温爆管,提出用气动高频扰动技术进行防范的措施。

Countermeasures against Superheat due to Fouling-blocked Theittling Orifice of Water Wall of Concurrent Boiler in Ultra-supercritical Units

Pipe burst always occurs due to superheat of water wall of boiler. Therefore, by taking ultra-supercritical unit made with Mitsubishi technology as an example, the paper analyzes causes for pipe burst in terms of structure and points out that massive vertical theittling orifice designed and such influences as orifice structure, potential difference of feedwater and pH value may result in fouling, which influences feedwater flow, reduces the cooling, and therefore causes superheat of pipe wall and pipeburst. The paper proposes the countermeasure of pneumatic high-frequency disturbance technology.