材料期刊网

原地浸矿回收稀土资源时,因注液不当等原因,容易引发滑坡等地质灾害.选择陡坡开采矿块,现场实验研究裸脚式稀土矿山的原地浸矿渗流过程及其引起的边坡变形规律,得到如下结论.实验矿块的浸润面接近临界水位时,仍有26.5％的矿层处于非饱和状态,因而影响了离子交换效率和资源回收率,是造成“复灌”回收龙南类型离子型稀土资源的一个主要原因.实验矿块矿层饱和体积比为65.0％时,原地浸矿的渗流场进入平衡期,在平衡期之前,注液强度增加6天后裂缝宽度才有明显变化;进入平衡期之后,裂缝宽度变化滞后注液强度增加3天,滞后注液强度减小2天.对于坡度均一的陡坡,如果原地浸矿前期注液强度过大,易引发推移式滑坡,剪出口出现在半山腰以上,后期注液强度过大,易引发牵引式滑坡,剪出口出现在山脚下;对于上陡下缓的陡坡,原地浸矿易引发推移式滑坡.

Geological disasters such as landslides may occur for reasons like unsuitable liquid injection during in-situ leach mining of ion-absorbed rare-earth mineral.To study the seepage process and the deformation rule of slope in rare earth mine during in-situ leach mining,the in-situ leach mining tests have done in a steep slope of ore block.It is found that the unsaturated zone proportion of the whole rare earth deposit is still up to 26.5％ when the phreatic surface of ore block reaches nearly the critical groundwater table.The unsaturated zone reduces the ion-exchange efficiency and the rare-earth recovery rate,which is a main reason why the reperfusion method was used in the ion-absorbed rare earth mineral of Longnan type to recover the rare earth again.When the saturated volume ratio of rare earth deposit in test area is 65.0％,the seepage field of in-situ leach mining is in the balance period.Before the balance period,after 6 days' increase of the liquid injection intensity,the crack width is changed.After the balance period,the crack width will be changed when increasing the liquid injection intensity for 3 days or decreasing the liquid injection intensity for 2 days.For the gradient of steep slope is steady,the oversized liquid injection intensity in early stage may easily trigger the thrust load caused landslide,and the shear opening appears on the mountainside.The oversized liquid injection intensity in later period can trigger pull landslide,and shear opening appears on the foot of the mountain.If the slope is steep in upper part and gentle in lower part,the thrust load caused landslide easily occurrs.