粉煤灰焙烧预处理对微波碱溶法溶出硅、铝的影响

摘要

Roasting pretreatment of fly ash and leaching of silicon and aluminum from the fly ash were researched .Effects of roasting temperature , roasting time ,and the mass ratio between fly ash and alkali on leaching of silicon and aluminum by microwave alkali dissolution were examined .The experimental results show that at the conditions of roasting temperature of 600 ℃ and the mass ratio of fly ash and alkali of 1∶1 ,fly ash is roasted for 1 .5 h ,then is leaching for 2 h using alkali solution of 300 g/L under temperature of 90 ℃ ,mass ratio between liquid and solid of 15∶1 ,leaching of silicon and aluminum reach 87 .5% and 44 .04% ,respectively .Compared with the direct microwave leaching , leaching of silicon and aluminum are higher .%研究了粉煤灰焙烧预处理、微波碱溶法溶出硅、铝，考察了焙烧温度、焙烧时间及灰碱配比对微波碱溶法溶出硅、铝的影响。试验结果表明：粉煤灰在600℃、物料配比1∶1、焙烧时间1．5 h条件下焙烧后，再用质量浓度为300 g/L的碱液，在90℃、液固体积质量比15∶1条件下溶出2 h ，硅溶出率达87．5％，铝溶出率达44．04％，相比不经焙烧直接微波溶出，硅、铝溶出率均提高1倍以上。