高硫高砷金精矿三相流化床流动特征模拟

Simulation of Flow Characteristics of Three-phase Fluidized Bed for High-sulfur and High-arsenic Gold Concentrate

常温常压条件下基于欧拉模型,利用Fluent软件对高1.6m、内径0.09m的高硫高砷金精矿三相流化床流动特征进行了数值模拟。模拟过程以空气为气相且为连续相,液态水为液相,密度为3.2g/cm3、粒径为0.5mm的高硫高砷金精颗粒为固相。模拟结果显示,流场的压力从计算域的入口到出口逐渐降低,速度场的变化对气液固局部相含率的分布影响显著;在径向上,气含率(εg)从计算域中心往边壁降低,在轴向上也逐渐降低;固含率(εs)从计算域的入口到出口逐渐减小,从计算域中心向边壁εs增加。模拟结果与实验结果一致,可为合理设置气流速度以及金矿投放量提供依据。

The numerical simulation was conducted using the Fluent software based on the Euler model for the flow characteristics of three-phase fluidized bed （ 1.6 m in height and 0.09 m in internal diameter） of a high-sulfur and high- arsenic gold concentrate under normal conditions. In the simulation, air was taken as continuous gas phase, water as liquid phase and the high-sulfur and high-arsenic gold concentrate with particle size of 0.5 mm and density of 3.2 g/cm3 as solid phase. Results showed that pressure of the flow field reduced gradually from the entrance to the exit of the computational domain. The variation in the velocity field significantly affected the distribution of local phase holdups. The gas holdup （εg） decreased from the center to the edge of the computational domain in the radial direction and gradually decreased in the axial direction too. While the solid holdup （ε3） increased from the center to the edge of the computational domain, but gradually decreased from the entrance to the exit. The simulation results were consistent with the experimental results, which will be helpful for setting reasonable air velocitv and appropriate dosage of gold.