电站锅炉掺烧劣质煤屏式过热器防结焦研究

Investigation on Anti-coking of Platen Superheater in Utility Boiler burning Blended Inferior Coal

针对某电厂600 MW锅炉掺烧劣质煤频繁掉焦情况,使用监测屏底烟温结合常用主力煤种与特定掺烧劣质煤种的特性对其掺烧比例进行研究,并提出一种屏式过热器底部防结焦系统。综合考虑锅炉的安全性与经济性,该机组在590 MW负荷下,锅炉燃烧伊泰煤中掺烧纳源煤最佳比例为17%。优先考虑锅炉经济性,可接受锅炉屏底出现轻微结焦时,这一掺烧比例最大为27%。屏式过热器底部防结焦系统能满足锅炉安全运行监测并控制锅炉屏式过热器结焦,有利于防止锅炉屏式过热器底部出现严重结焦,保证火电厂安全运行。

Burning blended inferior coal in a coal-fired power plant produces frequent slag dropping. In view of this situation, this study combines monitoring the temperature in bottom section of platen superheater with commonly used coal to blend with a specific inferior coal to analyze the blending ratio, and presents a system for anti-coking of the bottom section of platen superheater. Comprehensively considering security and economy of boiler, the unit is under load of 590MW, the optimal blending ratio of Nayuan coal is 17% when burning Yitai coal with blending the inferior coal of Nayuan. The maximum blending ratio of Nayuan coal is 27% when it gives priority to the cost economy of boiler and slight coking is acceptable for the bottom section of platen superheater. The system for anti-coking of the bottom section of platen superheater can meet boiler safety operation monitoring and control of coking of platen superheater, which avoids coking seriously in the bottom section of platen superheater for the safety operation of thermal power plant.