含锰磁铁矿球团氧化固结机理分析  

Analysis on oxidative consolidation mechanism of manganese-containing magnetite pellets

作　　者：付旭刚 马轲 巨建涛[2] 邢相栋[2] FU Xu-gang;MA Ke;JU Jian-tao;XING Xiang-dong(Ironmaking Plant,Gansu Jiugang Steel Group Hongxing Iron and Steel Co.,Ltd.,Jiayuguan 735100,Gansu,China;School of Metallurgical Engineering,Xi′an University of Architecture and Technology,Xi′an 710055,Shaanxi,China)

机构地区：[1]甘肃酒钢集团宏兴钢铁股份有限公司炼铁厂,甘肃嘉峪关735100 [2]西安建筑科技大学冶金工程学院,陕西西安710055

出　　处：《中国冶金》2022年第7期80-86,共7页China Metallurgy

摘　　要：为促进含锰磁铁矿在球团上的应用,通过造球试验,并借助X射线衍射和扫描电子显微镜等检测手段,系统地分析了Mn_(3)O_(4)对球团矿氧化固结机理的影响。结果表明,随着Mn_(3)O_(4)质量分数从0%增加至7%,球团抗压强度从2458 N/个降到1810 N/个,孔隙率从22.7%增大至26.2%。随着Mn_(3)O_(4)的增加,在赤铁矿晶界和硅酸盐相中形成新的MnFe_(2)O_(4)固熔体,固熔体扩大了基体中的裂纹,破坏了赤铁矿的连续结晶;硅酸盐含量增加也极大地抑制了赤铁矿晶粒的生长,使含锰球团的基体由致密变为多孔,球团矿强度降低。故对生产企业来说,Mn_(3)O_(4)对球团的固结强化有负面影响,其适宜的质量分数应在3%以内。In order to promote the application of manganese-containing magnetite in pellets,the effect of Mn_(3)O_(4) on the oxidative consolidation mechanism of pellets was systematically analyzed by means of pelletizing tests and detection methods such as X-ray diffraction and scanning electron microscopy.The results show that when the mass fraction of Mn_(3)O_(4) increases from 0%to 7%,the compressive strength of the pellets decreases from 2458 N/piece to 1810 N/piece,and the porosity increases from 22.7%to 26.2%.With the increase of Mn_(3)O_(4),a new MnFe_(2)O_(4) solid solution is formed in the hematite grain boundary and silicate phase.The solid solution expands the cracks in matrix and destroys the continuous crystallization of hematite.The increase of silicate content greatly inhibits the growth of hematite grains,which makes the matrix of manganese-containing pellets change from dense to porous,and its strength of pellets decrease.Therefore,for production enterprises,Mn_(3)O_(4) has a negative impact on the consolidation and strengthening of pellets,and its appropriate mass fraction should be within 3%.

关 键 词：球团矿 磁铁矿 Mn_(3)O_(4) 抗压强度 固结机理 

分 类 号：TF046.6[冶金工程—冶金物理化学]