离子型稀土浸矿过程中渗透性变化规律的试验研究

离子型稀土矿体的渗透性对浸矿工艺和浸矿引起边坡稳定变化具有重要影响,为此,采用室内柱浸试验研究渗流过程离子型稀土渗透性变化规律,通过对比原矿和筛分样的渗透系数变化,探讨了浸矿过程渗透系数的变化机理.研究结果表明:在清水渗流过程中,微颗粒迁移引起渗流稳定时间增长.渗流变化幅度增大,随着水力梯度的增大,流场稳定时间减小.流量变化幅度增加;浸矿过程中,离子吸附和离子交换使渗透系数减小,微颗粒迁移引起渗透系数增加,两种相反的作用同时存在,当水力梯度小于某一临界值时,引起渗透系数变化的主要原因是离子吸附和离子交换,当水力梯度大于某一临界值时,引起渗透系数变化的主要原因是微颗粒迁移,水力梯度增大,微颗粒迁移对渗透系数的变化影响增大;由于原矿级配良好,粒径大小相差悬殊,导致原矿比筛分样流场稳定时间更长. 

Permeability change rule of ion-adsorption rare-earth in ore leaching process

The permeability of ionic rare earth ore has a significant impact on leaching process and slope stability changes caused by leaching. Therefore , the indoor column leaching tests are used to study variation of rare earth ion permeability in percolation process. By comparing the permeability variation of ore and screening sample, the mechanism of permeability variation in leaching is explored . The results show that in water percolation process, micro-particles migration increases the seepage stability time and the range of seepage. With the increase of hydraulic gradient , the seepage field stable time decreases and flow range ability increases. In the process of leaching , the ion adsorption and the ion exchange reduces the permeability coefficient, micro-particles migrate increases the permeability coefficient , and two opposite effects coexist. When the hydraulic gradient is less than a critical value , Ion adsorption and ion exchange is the main reason changes permeability coefficient. When the hydraulic gradient is more than a critical value ,micro-particles migration is the main reason changes permeability coefficient. The impact of micro-particles migration on permeability coefficient increases with increasing of hydraulic gradient. As ore ’s particle size distribution is dispersed and graded better, the seepage filed of ore has longer stable time than screening sample.