一1000 MW机组低温省煤器应用浅析

Analysis on Application of Low Temperature Economizer for a 1 000 MW Unit

燃煤锅炉空预器出口烟气温度在120~150℃,烟气中所携带的大量热能没有被有效回收利用,造成能源浪费。应用低温省煤器可有效回收利用排烟余热加热凝结水,从而减少汽轮机的抽汽量,增强汽轮机的抽汽能力,同时还可有效减少脱硫用水,提高电除尘效率。介绍了低温省煤器在一1000MW燃煤机组中的实际应用,并针对应用中低温省煤器系统存在的振动、低温腐蚀、泄漏、积灰等问题进行了分析,提出了防范措施,给出了系统改进的方法及效果评价。

The outlet gas temperature of air preheater for coal-fired boiler is around 120-150℃,and a large amount of heat carried in the flue gas has not been effectively recycled and utilized,resulting in energy waste.The application of low temperature economizer can effectively recover and utilize exhaust waste heat to heat condensation water,so as to reduce the steam extraction of steam turbine and increase the extraction capacity of steam turbine.Meanwhile,it can also effectively reduce the water used for desulphurization and improve the efficiency of electric dust removal.This paper introduced the practical application of low-tem-perature economizer in a 1 000 MW coal-fired unit,and analyzed the problems of vibration,low-temperature corrosion,leakage and ash accumulation in the application of low temperature economizer system,put forward the preventive measures,and gave the method and effect evaluation of the system improvement.