摘要
受复杂矿物组成与特殊嵌布特征的限制,针对鲕状赤铁矿的传统选矿工艺难以实现理想的分离指标。为探究高磷鲕状赤铁矿的可还原性及直接还原过程中有害杂质元素的行为,本文以湖北宜昌地区长阳鲕状赤铁矿为研究对象,分别采用煤炭、CO及H_(2)三种还原剂开展直接还原试验,考察还原过程中铁、磷及铝等主要组分的矿物相变化与反应特征。长阳鲕状赤铁矿铁品位为50.53%,磷和铝质量分数分别为0.83%和3.87%,钙质量分数为6.73%,二元碱度为1.03。通过Factsage热力学软件计算,铁矿物分级还原过程中产生的FeO易与含铝矿物相反应生成难还原的铁铝尖晶石,从而抑制还原反应的深入进行。此外,鲕绿泥石等含铝物相在CaO熔剂存在下的还原行为得到显著改善,含磷物相中的磷元素则倾向于在较高温度下迁移并富集于还原产物中的金属铁相。在还原温度为1050℃、保温时间为90 min的条件下,采用煤炭、CO和H_(2)作为还原剂对该矿样进行直接还原处理,产物的金属化率分别为83.43%、88.90%和96.75%。通过分析球磨和磁选后的还原产物,三种还原方式在脱磷效果上差异较小,脱磷率均维持在约70%;而在铝的脱除方面,H_(2)还原产物表现出显著优势,其脱铝率达到68.33%,明显高于煤和CO还原所对应的45.71%和43.55%。对直接还原铁和磁选尾矿的XRD、SEM分析结果显示:H_(2)的还原效果最佳,能最大限度地破坏致密的鲕状结构,改善磁选工艺条件,提高金属化率。
Due to the limitations of complex mineral composition and special embedding characteristics,it is difficult to achieve the ideal separation index in the traditional beneficiation process for oolitic hematite.In order to explore the reducibility of high phosphorus osophyllum hematite and the behavior of harmful impurities in the process of direct reduction,in this paper,the Changyang oolitic hematite in Yichang area,Hubei province is used to carry out direct reduction experiments by using three reducing agents,namely coal,CO and H_(2),to investigate the mineral phase changes and reaction characteristics of the main components such as iron,phosphorus and aluminum during the reduction process.The Changyang oolitic hematite has an iron grade of 50.53%,a mass fraction of phosphorus and aluminum of 0.83%and 3.87%,a mass fraction of calcium of 6.73%,and a binary alkalinity of 1.03.Through Factsage thermodynamic software calculation,FeO produced during iron ore grading reduction easily reacts with aluminum-containing minerals to produce hard-to-reduce iron-aluminum spinel,thereby inhibiting the in-depth progress of the reduction reaction.In addition,the reduction behavior of aluminum-containing phases such as chamoisite is significantly improved in the presence of CaO flux,while the phosphorus elements in the phosphorus-containing phase tend to migrate at higher temperatures and are enriched in the metallic iron phase in the reduction products.Under the condition of reducing temperature of 1050℃and holding time of 90 min,coal,CO and H_(2) are used as reducing agents to directly reduce the ore sample,and the metallization rates of the products are 83.43%,88.90%and 96.75%,respectively.By analyzing the reduction products after ball milling and magnetic separation,the three reduction methods have little difference in dephosphorization effects,and the dephosphorization rate is maintained at about 70%;while in terms of aluminum removal,H_(2) reduction products show significant advantages,with its dealumination rate reaching 68.33%,which is significantly higher than the 45.71%and 43.55%corresponding to coal and CO reduction.XRD and SEM analysis results of direct reduced iron and magnetic separation tailings show that H_(2) has the best reduction effect,which could destroy the dense oolite structure to the greatest extent,improve the magnetic separation process conditions,and increase the metallization rate.
作者
周仙霖
陈仡煌
陈铁军
罗艳红
万军营
申跃洪
ZHOU Xianlin;CHEN Yihuang;CHEN Tiejun;LUO Yanhong;WAN Junying;SHEN Yuehong(Wuhan University of Science and Technology School of Resources and Environmental Engineering,Wuhan 430081;Wuhan University of Science and Technology Hubei Province Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources,Wuhan 430081,Hubei,China;Changyang Xinshougang Mining Co.,Ltd.,Yichang 443522,Hubei,China)
出处
《烧结球团》
北大核心
2025年第4期81-90,113,共11页
Sintering and Pelletizing
基金
湖北省重点研发计划资助项目(2022BCA062)
中国宝武低碳冶金创新基金资助项目(BWLCF202107)。
关键词
高磷鲕状赤铁矿
氢还原
直接还原铁
矿物相转变
high phosphorus osophyllum hematite
hydrogen reduction
direct reducted iron
mineral phase transformation
