液态添加剂对CFB锅炉SNCR脱硝的影响

为提高SNCR脱硝技术在低温下的脱硝效率,选取乙醇、NaCl、Na OH三种液态物质作为添加剂,在小型机理脱硝实验台和中等规模脱硝实验台上开展了研究。研究结果表明,小型实验台上,650℃、添加剂加入比例0~0.6条件下,乙醇可将脱硝效率从5%提升到45%,微量的(20×10-6)NaCl可以提高800℃以上的脱硝效率。在中等规模脱硝实验台上,乙醇因具有最佳的混合条件不同温度下对脱硝的促进作用差异明显,NaCl,NaOH因床料含有Na对脱硝无明显促进作用。添加剂与还原剂混合条件、床料成分等会使添加剂在CFB锅炉实际使用过程中产生与机理实验相差较大的结果。

Effect of liquid additives on SNCR denitrification process in CFB boiler

In order to improve the denitration efficiency under low temperature，ethanol/NaCl/NaOH were selected as liquid additives and the experiment was carried out on both a small scale denitration experimental system and a medium scale denitration experimental system.In the small scale denitration experimental system，ethanol can improve the denitration efficiency from 5% to 45%，trace amounts of (20×10-6），NaCl improves the denitration efficiency from 800 ℃.In the medium scale denitration experimental system，different additives enhance the denitration process differently.Because of the best mixing condition，at different temperatures ethanol has different effects under different amounts.As the bed material containing Na，NaCl/NaOH does not have obvious effect on enhancing denitration process.The mixing condition between additives and flue gas，the composition of bed material，etc.make big differences in using additives in CFB boiler and the experimental result.