Al_2O_3质量分数对高碱度烧结矿软熔滴落性能影响  

Influence of Al_2O_3 content on softening-melting property of high basicity sinter

作　　者：王喆[1] 张建良[1] 左海滨[1] 高冰[1] 李峰光[1] 王润博[1] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083

出　　处：《钢铁》2015年第7期20-25,76,共7页Iron and Steel

基　　金：国家重点基础研究发展(973)计划资助项目(2012CB720401)

摘　　要：对Al2O3质量分数不同的高碱度烧结矿进行了荷重软化熔滴试验,并通过对不同温度下烧结矿微观结构和矿物组成的分析,进行了Al2O3质量分数对烧结矿软熔滴落性能影响机制的探讨。试验结果表明:Al2O3质量分数增加促进了还原过程中钙铝黄长石(2Ca O·Al2O3·Si O2)和浮士体共晶相(2Ca O·Si O2-2Ca O·Al2O3·Si O2-Fe O)等低熔点富铝相的生成,导致高Al2O3烧结矿在较低温度下出现开气孔孔隙封闭,从而降低了压差陡升温度。在熔融滴落阶段,高Al2O3烧结矿中渣相的Al2O3质量分数较高。存在于金属铁颗粒之间渣相的液相线和黏度随Al2O3质量分数增加而提高,在一定程度上降低金属铁颗粒的聚合,使得烧结矿的滴落温度提高。同时,高Al2O3烧结矿具有较宽的熔滴区间,使得熔融滴落区间的透气性较差。Softening and melting tests under load of sinter with varying Al2O3 content were carried out. In addition,microstructure and mineral composition of sinter at different temperatures were also analyzed and the mechanism that the effect of Al2O3 content on sinter softening and melting property was elucidated. Results showed that the increase of Al2O3 content in sinter favored the formation of Al2O3-rich slag phase with lower melting point,such as gehlenite（2CaO·Al2O3·SiO2）and the eutectic（2CaO·SiO2-2CaO·Al2O3·SiO2-FeO）,resulting in the blockage of open pore. During melting-dripping process,slag phase of high Al2O3 sinter had a relative higher Al2O3 content. With the increase of Al2O3 content,the liquidus temperature and viscosity of slag phase existing between metallic iron particles was deteriorated. It decreased the concentration of metallic iron and then increased the dripping temperature. Meanwhile,high Al2O3 content sinter was associated with a thicker melting-dripping zone,leading to the deterioration of sinter bed permeability.

关 键 词：烧结矿 Al2O3质量分数 软化熔滴性能 开气孔结构 烧结矿微观结构 

分 类 号：TF046.4[冶金工程—冶金物理化学]