Kinetic study on microwave-enhanced direct reduction of titanomagnetite concentrate with coal  

作　　者：Peng Liu Si-yu Gong Yu-wen Chao Bing-guo Liu Li-bo Zhang En-hui Wu 

机构地区：[1]State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming University of Science and Technology,Kunming 650093,Yunnan,China [2]Yunnan Provincial Key Laboratory of Intensification Metallurgy,Kunming 650093,Yunnan,China [3]National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology,Kunming 650093,Yunnan,China [4]Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,Yunnan,China [5]Key Laboratory of Unconventional Metallurgy,Kunming University of Science and Technology,Kunming 650093,Yunnan,China [6]Panzhihua University,Panzhihua 617000,Sichuan,China

出　　处：《Journal of Iron and Steel Research International》2023年第3期429-445,共17页

基　　金：National Key Research and Development Program of China(2018YFC1900500);Yunnan Province Special Key Project of Basic Research(202101as070014);Scientific Research Fund of Panzhihua University(XJ2022001301).

摘　　要：Titanomagnetite concentrate is one of the important titanium resources.The apparent activation energy(Ea)of the direct reduction of titanomagnetite concentrate was composed of two parts(average activation energy:E_(a)=E_(a-L)+E_(a-Step1),where E_(a-L) is the lattice energy of titanomagnetite concentrate,and is the activation energy of step 1 for the reduction of titanomagnetite concentrate in the route of.Fe^(3+)→^(Step1)Fe^(2+)→^(Step2)Fe_(2)O^(2)→^(Step3)Fe^(0)).Ea(583.43 kJ/mol),(426.4 kJ/mol),and(157.0 kJ/mol)were calculated by the model-free methods based on thermogravimetry and Dmol3 module.Combined with the analysis of activation energy fluctuation and the shifting trend of related mechanism functions,the reduction kinetic system with three main characteristics,namely nucleation,diffusion and concentration fluctuation,was established.In addition,the scanning electron microscopy comparison analysis of the samples from microwave reduction and conventional reduction shows that microwave heating could realize the microstructure Ti-Fe separation and reduce the lattice energy of the titanomagnetite concentrate,thus enhancing the reduction process by 7.68%from the perspective of activation energy.

关 键 词：TITANOMAGNETITE KINETICS Lattice energy REDUCTION MICROWAVE TITANIUM 

分 类 号：TF651[冶金工程—钢铁冶金]