基于模型试验的散装铁精矿流态化细观规律

Mesoscopic Mechanism of Fluidization for Bulk Iron Ore Concentrates Based on Model Test

摘要:

利用室内振动台模型试验，对散装铁精矿流态化细观规律进行了研究.基于细观图像采集分析系统，研究了铁精矿在流态化演化过程中颗粒间及颗粒与水分间的相互作用，分析了颗粒长轴方向、平均接触数、平面孔隙率等演化规律，探讨了铁精矿流态化细观规律及其与宏观现象间的联系.结果表明：水分迁移在铁精矿流态化演化过程中至关重要，其宏观表现是水液面上升；细观组构是控制铁精矿宏观力学行为的重要参数，其所反映的规律与宏观现象一致.

关键词:铁精矿; 流态化; 细观组构; 配位数; 模型试验

Abstract:

A shaking table model test was carried out to study the mesoscopic mechanism of fluidization for iron ore concentrates in bulk under dynamic loading. By means of micro visualization system, meso evolutions of granular fabric were investigated including orientation of particle long axis, average coordination numbers and porosity. And the interaction between particles and water during the fluidization was analyzed. Then, the connection between meso mechanism and macro phenomenon was discussed. The results show that the water transfer, namely, the rising of water level, is important in the fluidization of iron ore concentrates. The mesoscopic fabric of iron ore concentrates, which is consistent with macro phenomenon, is an important parameter for the control of macroscopic mechanical behavior of iron ore concentrates.

Key words:iron ore concentrates; fluidization; meso fabric; coordination number; model test