球团气基还原联合高温熔分实现高磷铁矿脱磷的研究  

Research on the gaseous reduction of pellet followed by high-temperature melting separation for phosphorus removal from high-phosphorus iron ore

作　　者：候晓梅 于浩 唐惠庆 郭占成 HOU Xiaomei;YU Hao;TANG Huiqing;GUO Zhancheng(State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学钢铁冶金新技术国家重点实验室,北京100083

出　　处：《江西冶金》2023年第4期290-297,共8页Jiangxi Metallurgy

基　　金：国家自然科学基金资助项目(U1960205)。

摘　　要：针对高磷铁矿脱磷提铁的难题,文中提出了球团气基还原联合高温熔分的工艺路线。通过化学分析、X射线衍射(XRD)和扫描电子显微镜-能谱(SEM-EDS)分析了高磷铁矿球团的组成成分、矿相结构、微观形貌,探究了不同还原气氛(CO、H_(2))下球团的还原行为,并对金属化球团高温熔分获得低磷铁水的主要影响因素进行了研究。结果表明,鲕状高磷铁矿制备成球团,经过氧化焙烧后,原矿粉中的鲕粒结构被彻底破坏,球团中Fe^(2+)含量为0.69%;当还原温度为1 173 K时,高磷铁矿球团在H_(2)气氛下的还原性优于CO气氛,而在较优条件50%H_(2)-50%N_(2)(体积分数)气氛下进行还原焙烧后,球团的金属化率可达90%。熔分过程中,向金属化球团中添加CaO有利于获得低磷铁水,当金属化球团中CaO添加比例为15%(质量比),熔分后可以获得磷含量为0.35%的铁水,且铁回收率为88%。For the problem of phosphorus removal from the high-phosphate iron ore,a process route of the gaseous reduction of the pellet combined with high-temperature melting separation was proposed.The composition,mineral phase,and micromorphology of high-phosphorus iron ore pellets were analyzed by chemical analysis,Scanning Electron Microscopy-Energy Dispersion Spectroscopy(SEM-EDS),and X-ray diffraction(XRD).The reduction behavior of pellets under different reducing atmospheres(CO,H2)was analyzed.The major influencing factors for obtaining low-phosphorus molten iron by high-temperature melting of metalized pellets were investigated.The results show that the pellets could be prepared by oolitic high-phosphorus iron ore.After oxidation roasting,the oolitic structure in the original ore powder is destroyed,and the content of Fe2+in the pellets is 0.69%.At the reduction temperature of 1173 K,the reducibility of high-phosphate iron ore pellets under the H2 atmosphere is better than that under the CO atmosphere.The metallization ratio of pellets could reach 90%under an N2∶H2=1∶1(volume ratio)atmosphere.In the melting separation process,the addition of CaO to the metalized pellets is beneficial to obtain low-phosphorus molten iron.Adding 15%(mass fraction)CaO to the metalized pellets could obtain molten iron with a phosphorus content of 0.35%and iron recovery of 88%after melting.

关 键 词：高磷铁矿球团 气基还原 高温熔分 脱磷 

分 类 号：TF537[冶金工程—钢铁冶金]