Reaction behavior and non-isothermal kinetics of suspension magnetization roasting of limonite and siderite  

作　　者：Qiang Zhang Yongsheng Sun Yuexin Han Yanjun Li Peng Gao 

机构地区：[1]School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,China [2]National-local Joint Engineering Research Center of High-efficient exploitation technology for Refractory Iron Ore Resources,Shenyang 110819,China [3]State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2023年第5期824-833,共10页矿物冶金与材料学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.51874071 and 52022019)。

摘　　要：In order to develop limonite and decrease CO_(2) emissions,siderite is proposed as a clean reductant for suspension magnetization roasting(SMR) of limonite.An iron concentrate(iron grade:65.92wt%,iron recovery:98.54wt%) was obtained by magnetic separation under the optimum SMR conditions:siderite dosage 40wt%,roasting temperature 700℃,roasting time 10 min.According to the magnetic analysis,SMR achieved the conversion of weak magnetic minerals to strong magnetic minerals,thus enabling the recovery of iron via magnetic separation.Based on the phase transformation analysis,during the SMR process,limonite was first dehydrated and converted to hematite,and then siderite decomposed to generate magnetite and CO,where CO reduced the freshly formed hematite to magnetite.The microstructure evolution analysis indicated that the magnetite particles were loose and porous with a destroyed structure,making them easier to be ground.The non-isothermal kinetic results show that the main reaction between limonite and siderite conformed to the two-dimension diffusion mechanism,suggesting that the diffusion of CO controlled the reaction.These results encourage the application of siderite as a reductant in SMR.

关 键 词：reaction behavior non-isothermal kinetics suspension magnetization roasting SIDERITE LIMONITE CO_(2)emissions 

分 类 号：TG307[金属学及工艺—金属压力加工]