大屯锡矿同步尾砂立式砂仓装砂过程数值模拟研究

Numerical simulation study on sand loading process of synchronous tailings vertical sand bin in Datun tin mine

为了确定立式砂仓装砂过程中,砂仓内各尾砂相浓密沉降规律及堆积过程中所用尾矿的浓密特性及各运行参数,利用Ansys-Fluent数值模拟软件建立立式砂仓的物理模型,采用Fluent数值模拟的方法,对立式砂仓内动态装砂过程进行模拟,模拟过程中对不同装砂高度上尾砂的总应力、各相的体积分数、体积浓度以及溢流浓度进行监测。结果表明:料质量浓度为38%、45%、50%时,当尾砂堆积装满整个砂仓时,最大装砂高度分别为25、24、22 m,砂仓底部砂浆尾砂所达到的极限体积浓度是一致的,都为54%,全尾砂在立式砂仓内部的沉降过程总体是大颗粒尾砂由于自身重力的优势可快速沉降,而135μm左右的颗粒相尾砂处于自身重力与上浮力近乎相等的情况,其分布相对均匀,30、33、42、59μm颗粒则最主要是分布在砂仓上部,一部分超细颗粒更是会溢流出仓。阐明了尾砂在砂仓内部的沉降规律,为矿山立式砂仓的实际作业提供一定理论依据。

To determine the density and settlement law of each tailings phase in the vertical sand bin during the sand loading process and the density characteristics and various operating parameters of the tailings used in the stacking process,the physical model of the vertical sand bin is established by using the Ansys-Fluent numerical simulation software.The dynamic sand loading process in the vertical sand bin is simulated by using the fluent numerical simulation method.In the simulation process,the total stress of the tailings at different sand loading heights and the volume fraction of each phase is calculated,volume concentration and overflow concentration shall be monitored.The results show that when the mass concentration of the material is 38%,45%,and 50%when the tailings pile up to fill the whole sand bin,the maximum filling height is 25 m,24 m,and 22 m respectively,and the maximum volume concentration of the mortar tailings at the bottom of the sand bin is the same,all of which are 54%.The settling process of the full tailings in the vertical sand bin is generally that the large tailings can settle rapidly due to their gravity,while 135μm grain phase tailings are in the condition that their gravity and buoyancy are nearly equal,and their distribution is relatively uniform,30,33,42,59μm grain phase tailings are mainly distributed in the upper part of the sand bin,and some of the ultra-fine particles will overflow out of the bin,which clarifies the settlement law of the tailings in the sand bin,and provides a theoretical basis for the actual operation of the vertical sand bin in the mine.