浮选过程颗粒输运行为数值模拟

摘要

浮选过程中颗粒相的输运行为对浮选效率有着直接的影响，根据颗粒间的相互作用理论，建立了浮选过程中待浮矿粒在气泡与液相中的输运方程。以实验室CPT浮选柱为研究对象，采用欧拉双流体模型计算气-液两相基本流场并耦合浮选过程矿粒输运的方法，获得矿粒在气-液两相中稳定的浓度场分布，实现浮选过程中气-液-固三相流动数值模拟。结果表明：实验室CPT浮选柱中发泡区域周围存在较大漩涡，具有较低的矿粒浓度，柱中气泡与矿粒的平均碰撞速率为2.156×108 m-3∙s-1，平均碰撞概率、捕获概率和脱附概率分别为0.017、0.904和0.097。%The transport behavior of the particle phase has a direct impact for flotation efficiency in the flotation process. Based on the theory of the interaction of particles, the transport equation for mineral particles to be floating in the bubbles and the liquid phase of the flotation process was conducted. The laboratory CPT flotation column was studied with Eulerian two­fluid model to calculate the gas­liquid two­phase flow, which was coupled with the method for mineral particles transport in flotation process to obtain concentration field distribution of the mineral particles in the gas­liquid two­phase. The gas­liquid­solid three­phase flow simulation in the flotation process was achieved with the methods above. The results show that large whirlpools are found around the flotation foam area in laboratory CPT column, and the flotation foam area has lower concentration of mineral particles, the average collision rate between bubbles and mineral particles in the column is 2.156×108 m-3∙s-1, and the average probabilities of collision, adhesion and detachment are 0.017, 0.904 and 0.097, respectively.