Behavior and mechanism of pre-oxidation improvement on fluidization in the fluidized reduction of titanomagnetite  

作　　者：Haoyan Sun Ajala Adewole Adetoro Zhiqiang Wang Qingshan Zhu 

机构地区：[1]State Key Laboratory of Mesoscience and Engineering,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China [2]School of Chemical Engineering,University of Chinese Academy of Sciences,Beijing 100049,China [3]Data Science,AI modeling Centre,University of Hull,Hull HU67RX,UK

出　　处：《International Journal of Minerals,Metallurgy and Materials》2024年第11期2458-2465,共8页矿物冶金与材料学报（英文版）

基　　金：grateful for financial support from the National Natural Science Foundation of China(Nos.22378405 and 51974287);the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA29040100);the National Key Research and Development Program of China(No.2023YFC2908002).

摘　　要：The direct reduction process is an important development direction of low-carbon ironmaking and efficient comprehensive utilization of poly-metallic iron ore,such as titanomagnetite.However,the defluidization of reduced iron particles with a high metallization degree at a high temperature will seriously affect the operation of fluidized bed reduction.Coupling the pre-oxidation enhancing reduction and the particle surface modification of titanomagnetite,the behavior and mechanism of pre-oxidation improvement on fluidization in the fluidized bed reduction of titanomagnetite are systematically studied in this paper.Pre-oxidation treatment of titanomagnetite can significantly lower the critical stable reduction fluidization gas velocity to 0.17 m/s,which is reduced by 56%compared to that of titanomagnetite reduction without pre-oxidation,while achieving a metallization degree of>90%,Corresponding to the different reduction fluidization behaviors,three pre-oxidation operation regions have been divided,taking oxidation degrees of 26%and 86%as the boundaries.Focusing on the particle surface morphology evolution in the pre-oxidation-reduction process,the relationship between the surface morphology of pre-oxidized ore and the reduced iron with fluidization properties is built.The improving method of pre-oxidation on the reduction fluidization provides a novel approach to prevent defluidization by particle surface modification,especially for the fluidized bed reduction of poly-metallic iron ore.

关 键 词：FLUIDIZATION direct reduction PRE-OXIDATION TITANOMAGNETITE iron whisker 

分 类 号：TF55[冶金工程—钢铁冶金]