摘要
研究硫酸钠和碳酸钠对高铝铁矿石还原焙烧铝铁分离作用机理的差异。结果表明:硫酸钠或碳酸钠均可显著改善高铝铁矿石的还原效果,添加硫酸钠可获得较好的铝铁分离效果,添加碳酸钠可获得较高的铁回收率。碳酸钠作用下,铁晶粒较小且与脉石矿物结合;而硫酸钠作用下金属铁颗粒长大,与脉石矿物界限分明,解离性能好,后者有利于铝铁分离。硫酸钠存在的还原体系形成新生相S、Na2S和FeS,在体系内以液相存在,为Fe2+离子的扩散提供液相环境,降低了Fe2+离子迁移的势垒,有利于Fe2+离子的扩散,从而为铁晶粒和铝硅酸钠的聚集提供有利途径;而碳酸钠存在的还原体系没有液相生成,Fe2+离子的迁移只能通过固相扩散进行,迁移阻力大,因此,铁晶粒与脉石矿物的界限不及添加硫酸钠时的分明。
The mechanism difference between Na2SO4 and Na2CO3 on the Al-Fe separation of the high aluminum iron ores was studied. The results indicate that Na2SO4 or Na2CO3 can improve the reduction effect of the high aluminum iron ores. Better Al-Fe separation effect can be obtained when using Na2SO4, and better iron recovery can be obtained when using Na2CO3. The size of metallic iron grains is relatively small, and the grains combine with gangue tightly as Na2CO3 is used. While the metallic iron grains grow large and the boundary between iron grains and gangue minerals is clear when reduced with sodium sulplate, which is benefit for the monomer liberation and obtains better Al-Fe separation effect. The sodium sulplate redox system forms new phases, such as S, Na2S and FeS, and they exist in the system in liquid form, which providing liquid environment for the spread of iron ions, thus decreasing the migration barrier of iron ion, which is benefit for the iron ion spread, and then providing beneficial way for the gathering of iron grains and gangue minerals. While there is no liquid phase forms in the sodium carbonate redox system, and the migration of iron ions is only through solid phase diffusion, then the migration resistance is large, so, the boundary between the iron grains and gangue minerals is less clearer than that of sodium sulphate.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2014年第8期2129-2136,共8页
The Chinese Journal of Nonferrous Metals
基金
国家杰出青年科学基金资助项目(50725416)
国家自然科学基金青年科学基金资助项目(51304055)
关键词
高铝铁矿石
硫酸钠
碳酸钠
铝铁分离
high aluminum iron ore
sodium sulplate
sodium carbonate
Al-Fe separation
