基于磁介质设计实现下游捕收强化弱磁性矿物分选效率及其机理研究

提高我国弱磁性矿产资源利用效率，对保障国家工业发展所需原料供应具有重要意义。立环脉动高梯度磁选设备在弱磁性矿物的分选中应用广泛，但由于主要采用介质上游捕收，机械夹杂仍较严重。提高给矿速度实现介质下游捕收能够提高选择性，但矿物回收率会急剧降低。基于磁介质下游捕收能够大幅度减少机械夹杂的事实，本项目通过磁介质材质组合和结构设计，利用非磁性部分的引流及空间阻碍作用和磁性部分的磁捕收作用，以介质设计方法和矿物分选机理为研究对象，结合仿真分析、理论计算和试验研究等方法，进行单根介质设计消除磁性颗粒在介质上游的累积和强化磁性颗粒在介质下游的累积、磁性颗粒捕集行为和累积行为理论分析以及多根介质的下游捕收磁选效果及参数优化等研究，实现低给矿流速（常规流速）下介质下游的强化捕收，大幅度减少机械夹杂的同时强化细粒磁性矿物的捕收效率，解决高梯度磁选分选效率低的问题，为弱磁性矿物的高效加工利用提供新思路和新途径。

Increasing the utilization of weakly magnetic mineral resources is of great significance for ensuring the raw material supply demanded for industrial development of China. Although the vertical ring pulsating magnetic separators are widely applied in the processing of weakly magnetic minerals, the mineral particles are mainly captured at the upstream side of the matrices and serious mechanical entrainment still occurs, resulting in the low separation efficiency. That is a key factor restricting the utilization of weakly magnetic minerals. Increasing the slurry velocity can realize the downstream capture of the matrices and enhance selectivity, but the recovery of the magnetic minerals will decrease dramatically. In this project, based on the fact that the capture of magnetic particles by the downstream side of the matrices in the longitudinal configuration of high gradient magnetic separation (HGMS) can significantly increase selectivity, enhanced downstream capture under low slurry velocity (normal velocity) is to be realized to significantly decrease the mechanical entrainment of gangue minerals and enhance the capture of fine magnetic minerals through matrix’s material combination and structure design, utilizing the drainage and space hindrance effect of the nonmagnetic part and the magnetic capture effect of the magnetic part. Concerning the matrix design and separation mechanism of downstream capture, single wire design for decreasing and eliminating the particle capture at the upstream side of the matrix, single wire design for enhancing the particle capture at the downstream side of the matrix, theoretical analyses of the particle capture by the downstream side of the matrix and particle buildup at the downstream side of the matrix, the magnetic separation tests and parameter optimization of downstream capture of multi matrices are to be investigated through finite element simulation, theoretical derivation and experimental research. The aim of this project is to significantly increase the separation efficiency of weakly magnetic minerals and at the same time, to provide new mentality and approach for the efficient utilization of weakly magnetic minerals.