MgO对高碱度烧结矿强度的影响及机理
来源期刊：中南大学学报(自然科学版)2012年第9期
论文作者：范晓慧 李文琦 甘敏 陈许玲 袁礼顺 季志云 余志元 黄晓贤 苏道
文章页码：3325 - 3330
关键词：MgO；高碱度烧结矿；液相生成特性；微观结构；成矿特征；转鼓强度
Key words：MgO; high basicity sinter; liquid phase formation characteristics; microstructure; mineralization characteristics; tumbler index
摘 要：研究MgO质量分数的提高对高碱度烧结矿转鼓强度的影响规律并揭示其作用机理。结果表明：当碱度为2.0的烧结矿MgO质量分数从1.15%提高到3.5%时，转鼓强度从71.33%降低到61.13%；随着MgO质量分数的增大，液相生成温度提高，液相量减少，MgO质量分数太高将造成烧结矿液相量不足；Mg2+主要固溶在磁铁矿中，Mg2+进入磁铁矿晶格，提高磁铁矿的稳定性，不利于磁铁矿氧化，使得烧结矿中磁铁矿质量分数增大，且针状铁酸钙黏结相质量分数减少；烧结液相量较少以及具有良好强度的针状铁酸钙质量分数降低是MgO降低烧结矿强度的主要原因；白云石的成矿能力比石灰石的弱，随着白云石用量增大，熔剂与铁矿石之间的反应能力下降，因此，烧结矿转鼓强度降低。
Abstract: The influence and mechanism of MgO on the tumbler index (TI) of high basicity sinter were studied. The result shows that TI of sinter decreases from 71.33% to 61.13%，while MgO mass fraction increases from 1.15% to 3.5%. The mechanism research shows that the temperature of liquid formation of sintering mix increases and the mass fraction of liquid phase decreases with the increase of MgO content. And Mg2+ mostly dissolves in magnetite which diffuses into crystal lattice of magnetite and makes the magnetite more stable. Therefore, the mass fraction of magnetite in sinter increases and needle-like calcium ferrite decreases due to the retarding of magnetite oxidation, which is the main reason why MgO deteriorates TI of sinter. Experiments also indicate that the mineralization ability of dolomite is weaker than that of limestone. TI of sinter can be improved by optimizing the size distribution of dolomite which can facilitate the mineralization of dolomite.
范晓慧，李文琦，甘敏，陈许玲，袁礼顺，季志云，余志元，黄晓贤，苏道
(中南大学 资源加工与生物工程学院，湖南 长沙，410083)
摘 要：研究MgO质量分数的提高对高碱度烧结矿转鼓强度的影响规律并揭示其作用机理。结果表明：当碱度为2.0的烧结矿MgO质量分数从1.15%提高到3.5%时，转鼓强度从71.33%降低到61.13%；随着MgO质量分数的增大，液相生成温度提高，液相量减少，MgO质量分数太高将造成烧结矿液相量不足；Mg2+主要固溶在磁铁矿中，Mg2+进入磁铁矿晶格，提高磁铁矿的稳定性，不利于磁铁矿氧化，使得烧结矿中磁铁矿质量分数增大，且针状铁酸钙黏结相质量分数减少；烧结液相量较少以及具有良好强度的针状铁酸钙质量分数降低是MgO降低烧结矿强度的主要原因；白云石的成矿能力比石灰石的弱，随着白云石用量增大，熔剂与铁矿石之间的反应能力下降，因此，烧结矿转鼓强度降低。
关键词：MgO；高碱度烧结矿；液相生成特性；微观结构；成矿特征；转鼓强度
FAN Xiao-hui, LI Wen-qi, GAN Min, CHEN Xu-ling, YUAN Li-shun, JI Zhi-yun, YU Zhi-yuan, HUANG Xiao-xian, SU Dao
(School of Minerals Processing & Bioengineering, Central South University, Changsha 410083, China)
Abstract:The influence and mechanism of MgO on the tumbler index (TI) of high basicity sinter were studied. The result shows that TI of sinter decreases from 71.33% to 61.13%，while MgO mass fraction increases from 1.15% to 3.5%. The mechanism research shows that the temperature of liquid formation of sintering mix increases and the mass fraction of liquid phase decreases with the increase of MgO content. And Mg2+ mostly dissolves in magnetite which diffuses into crystal lattice of magnetite and makes the magnetite more stable. Therefore, the mass fraction of magnetite in sinter increases and needle-like calcium ferrite decreases due to the retarding of magnetite oxidation, which is the main reason why MgO deteriorates TI of sinter. Experiments also indicate that the mineralization ability of dolomite is weaker than that of limestone. TI of sinter can be improved by optimizing the size distribution of dolomite which can facilitate the mineralization of dolomite.
Key words:MgO; high basicity sinter; liquid phase formation characteristics; microstructure; mineralization characteristics; tumbler index
