Abstract: The effects of feed concentration on the separation performance and particle movement behavior of the cyclone separation column were investigated based on numerical experiments. The results show that the increase of feed concentration reduces the recovery of particles in the underflow， increases the cut size， and decreases the misplacement of fine particle in the underflow. However， an excessively high feed concentration results in coarse particles misplaced in overflow. A high feed concentration means that the particle aggregation degree in the cyclone separation column， and the amounts of particles moving with the internal swirling flow increase. The axial velocity of particles increases with the increase of feed concentration on the Z=-400mm plane. The internal swirling flow region that the particles moving towards the spigot need to pass through increases， causing the increase of the possibility of the coarse particles being trapped by the inner swirling flow. The increase of the feed concentration reduces tangential velocity of particles on the Z=-400mm plane， leading to the decrease of centrifugal force on particles and the increase of the possibility of particles migrating inward， further increasing the aggregation of particles in the internal swirling flow region.

Key words: cyclone separation column; feed concentration; numerical simulation; separation performance; particle movement behavior