Green magnetization roasting technology for refractory iron ore using siderite as a reductant

• Published in: Journal of cleaner production 2019-01, Vol.206, p.40-50
• Main Authors: Sun, Yongsheng, Zhu, Xinran, Han, Yuexin, Li, Yanjun
• Format: Article
• Language: English
• Subjects: Decomposition; Green magnetization roasting; Phase conversation; Siderite
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2018.09.113

In the present study, a green magnetization roasting process was proposed by using siderite (FeCO3) as the reductant. The influences of the siderite dosage, roasting temperature and roasting time on the magnetization roasting process were investigated. The saturation magnetization of roasted samples was analyzed by a vibrating sample magnetometer (VSM), and the phase transformation was investigated by in situ X-ray diffraction (XRD). The optimal roasting conditions were determined to be a siderite dosage of 40% with a roasting temperature of 700 °C and a roasting time of 10.0 min. The saturation magnetization of the roasted product under optimal conditions was 70.19 A m2 kg−1. The siderite (FeCO3) was transformed to magnetite (Fe3O4) with the intermediate product of wustite (FeO) in the decomposition process. In the meantime, the hematite (Fe2O3) was reduced to magnetite (Fe3O4) by the carbon monoxide released from the decomposition of siderite. [Display omitted] •A green magnetization roasting process for refractory iron ore was proposed.•The optimal roasting temperature, siderite dosage and roasting time were identified.•Iron concentrate ore with 66.76% Fe content and 98.05% recovery was obtained by the proposed process.•The saturation magnetization of the roasted sample under the optimal condition was 70.19 A m2 kg−1.•The phase transformations of hematite reduction and siderite decomposition were investigated.