关键词: 高铁铝土矿, 铁, 氧化铝, 直接还原, 碱耗

Abstract: Low alumina-silica ratio ferric bauxite is difficult to be processed for its poor quality.Direct reduction is an effective method to utilize this type ores.The hematite is reduced to iron which can be recovered by magnetic separation, and the Al₂O₃ is translated into sodium aluminates which can be recovered from the solution.Analyzing distribution of Na₂O in final products and implementing recycling use of Na₂O are beneficial to reduce processing cost and protect environment.The experiment results show that 87.76% of the Na₂O loss is diffusion loss, among which 68.69% spread to pot,43.60% was in solid (liquid）phase and 56.40% in gas phase.The Na₂O content difference between raw-material and crucible affected the diffusion amount of Na₂O, appreciably.There is little Na₂O diffusion when the content difference is below 22%.The amount of Na₂CO₃ loss is increase with the accelerant content and the reducing atmosphere.  

Key words: Ferric bauxite, Iron,Alumina direct reduction, Direct reduction, Alkali consumption