高磷赤铁矿直接还原过程中不同添加剂脱磷的性能对比及分子动力学模拟研究  

Comparison of Dephosphorization Performance of Different Additives in Direct Reduction of High⁃Phosphorus Hematite and Molecular Dynamics Simulation

作　　者：钟志刚 李宗蔚 杨备[1] 罗良飞[1] ZHONG Zhigang;LI Zongwei;YANG Bei;LUO Liangfei(Changsha Research Institute of Mining and Metallurgy Co Ltd,Changsha 410012,Hunan,China)

机构地区：[1]长沙矿冶研究院有限责任公司,湖南长沙410012

出　　处：《矿冶工程》2024年第2期83-87,共5页Mining and Metallurgical Engineering

基　　金：国家重点研发计划项目(2021YFC2902504)。

摘　　要：通过试验对比了高磷赤铁矿直接还原焙烧过程中不同添加剂CaCO_(3)、Na_(2)CO_(3)、CaF_(2)的脱磷性能,结果表明,Na_(2)CO_(3)的脱磷性能更好,CaCO_(3)次之。利用分子动力学模拟统计计算使用3种不同添加剂后体系在焙烧过程中的桥氧分布和氧原子均方位移,查明了高磷赤铁矿直接还原过程中CaCO_(3)、Na_(2)CO_(3)、CaF_(2)的脱磷机制,结果表明,添加剂脱磷的作用机制是提高体系中自由氧含量或提高体系中氧原子的均方位移,减少体系中Si、P共用氧原子,从而抑制磷灰石的还原;添加剂脱磷性能与体系中氧原子均方位移呈正相关的规律。Experiments were carried out to compare dephosphorization performance of CaCO_(3),Na_(2)CO_(3)and CaF_(2)in direct reduction roasting process of high⁃phosphorus hematite.It is found that Na_(2)CO_(3)presents the best dephosphorization performance,followed by CaCO_(3).The molecular dynamics simulation was conducted to calculate the distribution of bridging oxygen and the mean square displacement(MSD)of oxygen atoms during the roasting process of the system with three different additives respectively,and the dephosphorization mechanism of CaCO_(3),Na_(2)CO_(3),CaF_(2)during the direct reduction process of high⁃phosphorus hematite was explored.The results show that the mechanism of dephosphorization by additives is to inhibit reduction of apatite by increasing the content of free oxygen or the MSD of oxygen atoms in the system and reducing the oxygen atoms shared by Si and P in the system.It is found that the dephosphorization performance of additives is positively correlated with the MSD of oxygen atoms in the system.

关 键 词：分子动力学模拟 直接还原 高磷赤铁矿 脱磷 脱磷剂 磷灰石 自由氧 均方位移 

分 类 号：TD925[矿业工程—选矿]