含铅锌难选赤褐铁矿还原焙烧及动力学  

Reduction Roasting of Refractory Hematite⁃Limonite Ore Containing Lead and Zinc Impurities and Its Kinetics Research

作　　者：罗立群[1,2] 雷严明 魏晨曦 叶远林 LUO Liqun;LEI Yanming;WEI Chenxi;YE Yuanlin(School of Resources and Environmental Engineering,Wuhan University of Technology,Wuhan 430070,Hubei,China;Hubei Key Laboratory of Mineral Resources Processing and Environment,Wuhan 430070,Hubei,China)

机构地区：[1]武汉理工大学资源与环境工程学院,湖北武汉430070 [2]矿物资源加工与环境湖北省重点实验室,湖北武汉430070

出　　处：《矿冶工程》2023年第2期86-90,96,共6页Mining and Metallurgical Engineering

基　　金：国家自然科学基金(51874219)。

摘　　要：针对含铅0.39%、含锌0.30%、全铁(TFe)含量47.04%的含铅锌难选赤褐铁矿,通过碳热还原焙烧实验,考察了还原焙烧过程中赤褐铁矿的还原效果和铅、锌杂质的脱除率;借助恒温热重分析,研究了还原焙烧过程反应分数、反应速率及动力学参数,探讨了难选赤褐铁矿碳热还原焙烧动力学。结果表明,在焙烧温度1200℃、还原剂碳氧比2.25、焙烧时间60 min条件下碳热还原焙烧,所得焙烧矿经弱磁选,可获得全铁品位89.63%、铁回收率86.09%的铁精矿,铅、锌杂质脱除率分别为98.97%、91.19%。含铁矿物主要转变为类球状金属铁颗粒,微区点含铁纯度可达99.4%以上。铁矿还原焙烧过程符合收缩边界控制反应机理和收缩球体模型,表观活化能为91.37 kJ/mol,指前因子为18.09 min^(-1),表明反应速率限制环节为固相扩散。研究结果可为类似矿石还原焙烧脱除有害杂质提供借鉴。A kind of refractory hematite⁃limonite ore containing 0.39%lead,0.30%zinc and 47.04%TFe was taken to perform carbothermic reduction roasting experiment,and the reduction effect of hematite⁃limonite ore and the removal rate of lead and zinc in the reduction roasting process were all investigated.The reaction fraction,reaction rate and kinetic parameters of the reduction roasting process were studied by means of thermogravimetric analysis at a constant temperature,and the kinetics of carbothermic reduction roasting of refractory hematite⁃limonite ore was also discussed.After 60⁃min roasting at 1200℃with the reducing agents of carbon and oxygen at a ratio of 2.25,the obtained roasted ore was subjected to low intensity magnetic separation,resulting in the yielded iron concentrate grading 89.63%TFe at 86.09%recovery and the removal rates of lead and zinc up to 98.97%and 91.19%,respectively.The iron minerals are mainly transformed into spherical metallic iron particles with iron purity over 99.4%in micro⁃zone.The reduction roasting process of iron ore follows the shrinkage boundary control reaction mechanism and shrinkage core model.The apparent activation energy is calculated to be 91.37 kJ/mol,and the pre⁃exponential factor is calculated to be 18.09 min^(-1),indicating that the rate⁃limiting reaction step is solid⁃state diffusion.This research can provide reference for removing harmful impurities from similar ores by reduction roasting process.

关 键 词：赤褐铁矿 还原焙烧 动力学 铅 锌 杂质 铁精矿 

分 类 号：TD981[矿业工程—选矿] TD982