高铁赤泥钙化还原过程液相生成抑制机理  

Mechanism of inhibiting liquid phase formation in calcification reduction process of iron-rich red mud

作　　者：李靖[1] 郑富强 景涛[1] 代友训[1] 王洪阳 侯传兵 陈玉 LI Jing;ZHENG Fuqiang;JING Tao;DAI Youxun;WANG Hongyang;HOU Chuanbing;CHEN Yu(Zhongye Changtian International Engineering Co.,Ltd.,Changsha 410205,Hunan,China;Anhui University of Science&Technology,Huainan 232001,Anhui,China;Rizhao Steel Co.,Ltd.,Rizhao 276800,Shandong,China)

机构地区：[1]中冶长天国际工程有限责任公司,湖南长沙410205 [2]安徽理工大学,安徽淮南232001 [3]日照钢铁有限公司,山东日照276800

出　　处：《烧结球团》2024年第5期88-95,共8页Sintering and Pelletizing

基　　金：湖南省重点研发计划资助项目(2023SK2079);2022年长沙市“小荷”青年人才创新项目。

摘　　要：高铁赤泥中赋存大量铁资源难以回收利用,钙化还原—磨选方法可实现赤泥中铁、铝组分的高效分离。针对高铁赤泥钙化还原过程中易形成液相,导致物料熔化和设备黏结的问题,本文提出分段式钙化还原—磨选技术路线,研究不同温度制度下,高铁赤泥钙化还原产物的形态、金属化率、微观结构、金属铁晶粒的生长规律和相关磨选指标。结果表明:采用分段钙化还原焙烧,可在低温阶段完成铁氧化物还原至金属铁和钙铝化合物形成的反应过程,在高温阶段完成金属铁颗粒的聚集长大过程,将低熔点物形成和高温焙烧分离进行,抑制液相生成。采用第一段1 125℃焙烧30 min、第二段1 200℃焙烧40 min的分段焙烧制度,还原过程无明显液相生成,金属铁颗粒的平均粒度达到21.52μm。还原产物经磨选后,所获得的还原铁粉TFe质量分数和Fe回收率分别达到92.84%和78.68%。本文研究成果可为高铁赤泥的资源化利用提供理论依据。It is difficult to recycle a large amount of iron resources in iron-rich red mud,and the calcification reduction-grinding method can realize the efficient separation of iron and aluminum components in red mud.In order to solve the problem that the liquid phase is easy to form during the calcification reduction process of iron-rich red mud,which leads to the melting of materials and the adhesion of equipment,a segmented calcification reduction-grinding technology route is proposed;the morphology,metallization rate,microstructure,growth law of metallic iron grains and related grinding indexes of calcification reduction products of iron-rich red mud under different temperature regimes are studied.The results show that the segmented calcification reduction roasting can complete the reaction process of iron oxide reduction to the formation of metallic iron and calcium-aluminum compounds at low temperature,and the aggregation and growth process of metallic iron particles at high temperature,and the formation of low melting point and high-temperature roasting can be separated to inhibit the formation of liquid phase.The first stage is roasted at 1 125 ℃ for 30 min and the second stage is roasted at 1 200 ℃ for 40 min,without obvious liquid phase formation during the reduction process,and the average particle size of the metal iron particles reaches 21.52 μm.After grinding,the TFe mass fraction and Fe recovery rate of reduced iron powder are obtained up to 92.84% and 78.68%,respectively.The results can provide a theoretical basis for the resource utilization of iron-rich red mud.

关 键 词：高铁赤泥 钙化还原 还原铁粉 液相形成 磨矿磁选 

分 类 号：TF09[冶金工程—冶金物理化学]