高铁铝土矿还原过程中的碱耗机理

采用化学分析,XRD,SEM和EDS等方法研究Na2O在产物中的分布及赋存状态,分析影响碱耗的因素和机理,有助于制定合理的工艺条件,降低成本和保护环境。从Na2CO3晶体的结构和能量变化角度研究熔融促进Na2O扩散的机理。研究结果表明:扩散损失的Na2O占总损失的87.76%,其中,43.60%属于固相扩散,56.40%属气相扩散。固相扩散量随物料与容器间的Na2O质量分数差的增加而显著提高,而气相扩散则不受到影响。还原性气氛增强、还原时间延长、温度升高以及物料含Fe2O3和Al2O3会导致Na2O扩散量增加。

Alkali consumption mechanism on ferrous bauxite reduction process

Research methods such as chemical analysis,XRD,SEM and EDS were used to study Na2O distribution and existing form in products.It was beneficial to analyze factors and mechanism influencing alkali consumption to improve process conditions,reduce cost,and protect environment.The mechanism of diffusion accelerated by fusion was also investigated from the term of the structure of the crystal and the variation of the energy.The experimental results show that 87.76% of the Na2O loss is by diffusion.In the diffusion part,43.60% is in solid(liquid) phase,and 56.40% is in gas phase.The Na2O mass fraction difference between raw-material mixture and crucible appreciably impacts solid(liquid) phase diffusion amount,but there is nothing to do with gas phase diffusion.In addition,the enhancing of reducing atmosphere,increasing time and temperature,and the existence of Fe2O3,Al2O3 made more Na2O loss.