某330MW机组循环流化床锅炉脱硫效率分析

Analysis on desulfurization efficiency of a 330MW unit circulating fluidized bed boiler

针对某330MW机组CFB锅炉低床压运行时存在的脱硫效率下降,床内结焦风险增大等问题,在不同工况下对该机组脱硫效率进行测试,分析运行床压、石灰石粒径、操作水平、石灰石输送系统出力等控制参数对脱硫效率的影响。结果表明:造成该锅炉脱硫效率下降的原因是石灰石输送系统出力不足及石灰石粒径过小。对此,提出加大石灰石输送系统出力,适当增大石灰石的粒径,提高运行氧量和一次风量,增大高位二次风量等措施,以提高该锅炉脱硫效率,进而提高锅炉效率及环保水平。

During low bed pressure running of a 330 MW unit circulating fluidized bed （CFB）boiler,the de-sulphurization efficiency decreased and the slagging problem seemed getting serioud.Against this,perform-ance tests were carried out,under various working conditions.The effects of control parameters,such as the bed pressure,the particle size of limestone,the operational level,and the output of limestone conveying sys-tem in the running process,on desulfurization efficiency of the CFB boiler were investigated.The results show that,insufficient output of the limestone conveying system and undersize of limestone particles were major reasons for the low desulphurization efficiency of this unit.On this basis,several countermeasures were put forward,like increasing the output power of the limestone conveying system,enlarging the parti-cle size of limestone,increasing the operational oxygen content and the primary air volume,raising the sec-ondary air volume at higher locations,and others.