燃用高硫煤锅炉空预器选型分析

Analysis on the selection of air preheater for high sulfur coal fired boiler

为有效解决2×660MW燃用高硫煤超超临界机组空预器堵塞问题,研究了回转式空预器和管式空预器特性,分析了机组特点,提出了回转式空预器和管式空预器两级换热器串联方案,并探究了该方案对机组锅炉效率的影响。研究表明,相比于常规回转式空预器方案,采用回转式空预器和管式空预器两级换热器串联方案时,回转式空预器的出口排烟温度高于烟气酸露点,有效解决了机组空预器腐蚀堵塞问题,同时在保证设备安全下使锅炉效率提高1%。

In order to solve the problem of blockage in the air preheater of high sulfur coal fired boiler of 2×660MW ultra-supercritical unit effectively,the characteristics of rotary air preheater and tubular air preheater are studied,the characteristics of the power unit are analyzed,and a two-stage heat exchanger series connection scheme of rotary air preheater and tubular air preheater is proposed,and the influence of this scheme on the boiler efficiency of unit is explored.The results show that,compared with the conventional rotary air preheater scheme,when the rotary air preheater and tubular air preheater two-stage heat exchanger are used in series,the outlet exhaust gas temperature of rotary air preheater is higher than the flue gas acid dew point,which solves effectively the problem of corrosion and blockage of the air preheater of unit,and further increases the boiler efficiency by 1%under the guarantee of equipment safety.