超低排放燃煤机组管式GGH吹灰系统改造技术研究

Study on soot-blowing system retro fitting for tubular gas-gasheater of a large capacity utility boiler

本文以浙江温州某电厂660MW超低排放机组管式GGH烟气冷却器的吹灰系统为研究对象,将部分模块的吹灰工质改为压缩空气,进行对比试验。改造后通过实测,发现蒸汽吹灰会导致烟气中的湿度明显升高,而压缩空气吹灰不存在该问题,烟气湿度反而略降低。在吹灰频次相同的情况下运行一年后,采用压缩空气吹灰的模块比采用蒸汽吹灰的模块,烟气阻力降低20~70 Pa,换热器温降提高1~2℃,换热管积灰也相对较少,说明压缩空气吹灰效果较好。

In this paper,the soot-blowing system retrofitting for tubular gas-gas heater of a 660 MW boiler in Wenzhou Zhejiang has been implemented.Compressed air is employed in the soot blowing system instead of steam.The measurement after retro fitting shows that the humidity of flue gas increases obviously when the steam soot blowing system is working,while the humidity is slightly reduced when the air soot blowing system is operating.After one year operation with the same frequency of soot-blowing,the pressure drops of the tubular gas-gas heater using air soot-blowing system are 20-70 Pa less than that uses steam soot blowing system,in addition,the temperature drops are 1~2℃ higher.The photos also show that mount of ash deposition on the heating surface using pressured air is less than that using steam.