(1. 中南大学 资源加工与生物工程学院，长沙 410083；
2. 中南大学 冶金与环境学院，长沙 410083)
摘 要: 为了将锌焙砂中铁酸锌选择性地分解为ZnO和Fe3O4，研究在CO还原焙烧过程中铁酸锌的分解行为。采用HSC和Factsage软件计算铁酸锌在CO还原气氛下分解的热力学基础，再通过回转窑焙烧试验考察还原焙烧条件对铁酸锌分解行为的影响。结果表明:在适宜的温度和气氛下锌焙砂中的铁酸锌能选择性转化为ZnO和Fe3O4，CO浓度、p(CO)/p(CO+CO2)值、焙烧温度和时间是影响铁酸锌分解的主要因素，提高焙烧温度、延长时间、增加CO浓度和分压有利于铁酸锌的分解，也会促进FeO的生成；在最佳条件下，铁酸锌的分解率近70%，且过还原不严重。经XRD和SEM/EDS分析，产物主要以ZnO、Fe3O4、ZnS和Zn2SiO4为主，且颗粒粒度较小、疏松多孔及互相包裹严重。
关键字: 铁酸锌；锌焙砂；锌浸渣；还原焙烧；分解行为
（1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:In order to selectively decompose ZnFe2O4 contained in zinc calcine to ZnO and Fe3O4, the decomposition behavior of zinc ferrite during CO reduction roasting process was studied. The thermodynamic basis of ZnFe2O4 decomposition with CO was firstly calculated by HSC and Factsage software, then the effects of reduction roasting conditions on ZnFe2O4 decomposition behavior were investigated by reduction roasting test using rotary kiln. The results show that ZnFe2O4 can be selectively converted into ZnO and Fe3O4 at appropriate temperature and atmosphere. CO concentration, p(CO)/p(CO+CO2), roasting temperature and time have significant effects on the selective decomposition behavior, and increasing them are conducive to the decomposition of ZnFe2O4 and the generation of FeO. Under the optimum condition, the decomposition rate of ZnFe2O4 is nearly 70% without substantive over-reduction of iron. The roasting product mainly composes of ZnO, Fe3O4, ZnS and Zn2SiO4, and the particles are small, loose, porous and seriously mutual encapsulated according to XRD and SEM / EDS analyses.
Key words: zinc ferrite; zinc calcine; zinc residue; reduction roasting; decomposition behavior
