二次再热机组锅炉三段吹管技术研究

Technical Study on Three-Staged Pipe-Blowing Method Used in Double Reheat Unit

二次再热技术因其较高的热效率和较低的污染物排放正得到越来越广泛的应用。针对新机组的蒸汽吹管工艺亟待探讨,以二次再热超超临界660 MW锅炉为研究对象,在传统一段吹管、二段吹管方法的基础上,结合大容量超超临界二次再热锅炉受热面布置的实际,提出三阶段降压法蒸汽吹管工艺,较好地适应了新机组新技术的变化。实际靶板检验结果表明:斑痕数均少于5点,斑痕粒径均小于0.5 mm,完全符合国家规范要求,吹洗质量优良。提出并成功运用的三阶段降压法吹管工艺可为后续二次再热机组吹管提供实际参考。

Due to the higher thermal efficiency and the lower pollutant emissions,the double-reheat cycle technology is getting moreapplied in the industry..Therefore,the steam blowing process for the new units with double-reheat cycle calls for urgent study.In this paper,an ultra-supercritical 660 MW double-reheat boiler is taken as the study object.Based on the routine one-staged and two-staged pipe-blowing techniques,the three-staged pipe-blowing with pressure-reduction steam is proposed in accordance with the arrangement of the boiler heating surfaces.The results of the target plate test show that the number of the flushed spots are less than 5 and the diameters of the spots are all smaller than 0.5 mm,which completely meets the requirements of the national codes.The three-staged pressure-reduction pipe-blowing method,which produces good blowing quality,can provide practical reference for subsequent units with double reheat technology.