In this work, a green self-magnetization roasting technology for producing magnetite was proposed without adding additional. The regulatory mechanisms of the main factors (siderite dosage, roasting temperature, and roasting time) on the self-magnetization roasting process were investigated. In-situ kinetic of the self-magnetization roasting process was analyzed by the infrared gas analyzer, and the phase transformation was investigated by in-situ X-ray diffraction and Mössbauer. Under the optimal roasting conditions of 30% siderite dosage, 730 °C, and 7.5 min, the iron concentrate with Fe grade 68.82% and Fe recovery 99.48% was obtained. The kinetic and phase transformation results indicated that the self-magnetization roasting process was divided into two stages: siderite pyrolysis in the prophase stage, and hematite reduced to magnetite by reductant (FeO and CO) from siderite pyrolysis in the anaphase stage. The SEM analyses showed that the newborn magnetite crystals were mainly coarse-grained and needles, which fitted the kinetics characteristics for the Nucleation model. Using self-magnetization roasting technology, siderite and hematite would promote mutual reduction to improve product magnetism and roasting efficiency without adding reductant. Also, self-magnetization roasting will enhance the utilization rate of siderite, and it contributes to energy conservation and CO₂ emission reduction.

本工作提出了一种绿色自磁化焙烧生产磁铁矿的工艺，无需添加添加剂。研究了主要因素（菱铁矿用量、焙烧温度和焙烧时间）对自磁焙烧过程的调控机制。通过红外气体分析仪分析了自磁化焙烧过程的原位动力学，并通过原位 X 射线衍射和穆斯堡尔研究了相变。在菱铁矿用量30%、730℃、7.5 min的最佳焙烧条件下，得到Fe品位68.82%、Fe回收率99.48%的铁精矿。动力学和相变结果表明，自磁化焙烧过程分为两个阶段：前期菱铁矿热解，赤铁矿被后期菱铁矿热解的还原剂（FeO和CO）还原为磁铁矿。SEM分析表明新生磁铁矿晶体主要为粗粒和针状，符合成核模型的动力学特征。菱铁矿和赤铁矿采用自磁化焙烧技术，促进相互还原，提高产品磁性和焙烧效率，无需添加还原剂。此外，自磁焙烧会提高菱铁矿的利用率，有利于节能和CO 菱铁矿和赤铁矿在不添加还原剂的情况下促进相互还原，提高产品磁性和焙烧效率。此外，自磁焙烧会提高菱铁矿的利用率，有利于节能和CO 菱铁矿和赤铁矿在不添加还原剂的情况下促进相互还原，提高产品磁性和焙烧效率。此外，自磁焙烧会提高菱铁矿的利用率，有利于节能和CO₂减排。