烧结中使用钢渣磁选尾渣替代部分烧结熔剂的实验研究

摘要

Fundamental characteristics of magnetic separation tail slags were studied by chemical analysis,X-ray diffraction analysis,optical microscope analysis and other analysis methods.The microstructure and metallurgical properties of the sinter were studied,while magnetic separation tail slags were added into sintering material with 0,2.5％,5.0％ and 10.0％,respectively.The results show that when the mass fraction of tail slags in the sintering material is less than 5.0％,with the increase of tail slags content,calcium ferrite content in the sinter tends to increase,the sinter yield elevates,strength and drum strength both improve.Then all these metallurgical performances tend to decrease,while the mass fraction of tail slags continues to increase.However,the vertical sintering speed and productivity of sintering decrease if the content of tail slags in sintering increases.The reducibility index of sinter and the low temperature reduction degradation index can be improved with the increase of the slag content.And these performances decrease when the mass fraction of tail slags is more than 5.0％.With the increase of tail slags content,the high free flow temperature and soften-melting temperature of sinter make softening temperature intervals expand,and worsen the softening-melting properties of sinter.%通过化学分析、X线衍射分析、光学显微分析等方法对钢渣磁选后剩余尾渣进行基础特性分析,并将其按照质量分数0,2.5％,5.0％和10.0％的比例分别配入烧结原料中,研究其代替部分烧结熔剂对烧结矿显微结构、质量及冶金性能的影响.研究结果表明:当烧结原料中尾渣配入量小于5.0％时,随着尾渣配入量的增加,烧结矿中铁酸钙含量增加,烧结矿的成品率、落下强度及转鼓强度均逐渐增大,之后均开始降低,而垂直烧结速度及烧结利用系数则一直逐渐降低.烧结矿的还原度及低温还原粉化性能随着尾渣配入量得到改善,但当尾渣配入量大于5.0％时开始下降.尾渣的配入会提高烧结矿的自由流动及完全熔化温度,扩大软熔区间,使得烧结矿软熔性能变差.