In-situ reduction mechanism of hematite by bastnaesite during suspension magnetization roasting  

悬浮磁化焙烧过程中氟碳铈矿对赤铁矿的原位还原机制

作　　者：Wen-bo LI Shao-kai CHENG Rui QU Ji-jia CHEN 李文博;程绍凯;瞿瑞;陈继佳(东北大学资源与土木工程学院,沈阳110819;难采选铁矿资源高效开发利用技术国家地方联合工程研究中心,沈阳110819)

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

出　　处：《Transactions of Nonferrous Metals Society of China》2025年第3期965-974,共10页中国有色金属学报(英文版)

基　　金：the financial support from the National Key R&D Program of China(No.2022YFC2905800);the National Natural Science Foundation of China(Nos.52174242,52130406)。

摘　　要：To explore the spontaneous magnetization of iron-bearing rare earth ores during suspension roasting,binary minerals containing hematite and bastnaesite were used to investigate the effects of the roasting temperature,roasting time,and bastnaesite-to-hematite mass ratio on in-situ reduction of hematite in a N_(2) atmosphere.Relevant analytical tests were used to explore the mineral phase evolution during roasting,the magnetism and microstructure of the roasted products,the phase composition,and the surface element valence of concentrate.It was found that magnetic separation of the iron concentrate afforded an iron grade of 68.87% and a recovery of 93.18% under the optimum roasting conditions.During roasting,bastnaesite decomposed to generate CO_(2) and CO,and the compact structure of hematite was gradually destroyed,resulting in microcracks.Subsequently,the CO entered the surface of the hematite through the microcracks and reacted to form a magnetite shell,and the magnetite-encapsulated hematite particles were recovered via low-intensity magnetic separation.为探究含铁稀土矿在悬浮焙烧过程中的自磁化,以赤铁矿与氟碳铈矿混合矿为研究对象,考察N_(2)气氛下焙烧温度、焙烧时间和氟碳铈矿与赤铁矿质量比对赤铁矿原位还原的影响。采用相关分析检测研究焙烧过程中的矿相演变、焙烧产品的磁性和显微组织、精矿的物相组成及表面元素价态。结果表明,在最佳焙烧条件下,获得铁品位为68.87%、铁回收率为93.18%的磁选铁精矿。在焙烧过程中,氟碳铈矿分解生成CO_(2)和CO,同时赤铁矿的致密结构逐渐被破坏,产生微裂纹。随后,生成的CO随着裂隙进入赤铁矿颗粒表层并与其发生反应,形成磁铁矿壳,且这种磁铁矿包裹赤铁矿的颗粒可被弱磁选回收。

关 键 词：BASTNAESITE HEMATITE magnetization roasting in-situ reduction 

分 类 号：P57[天文地球—矿物学]