College of Mining Technology,Taiyuan University of Technology,Taiyuan　 030024,China

拓宽浮选粒度上限是浮选领域挑战的难题之一。应用三相流化床技术,在上升水流中引入气泡流,对比有无气泡对煤炭颗粒床层膨胀度的影响,得出气泡流的引入能够加强低密度颗粒的流化。并在单独上升水流、上升水流+气泡流和上升水流+气泡流+捕收剂(煤油)3种水流条件下,进行煤炭分选实验。结果表明,气泡流的引入,能够大幅减少低密度级颗粒悬浮所需的上升水流速度,气泡流对低密度级颗粒的影响强于高密度级,气泡的存在强化了颗粒密度、弱化了粒度对分选的影响;在上升气泡流中添加捕收剂后,低密度级颗粒与气泡形成颗粒-气泡结合体,低密度级颗粒便能够在较低的上升水流速度下进行分选,低速上升水流稳流度较低,保证了大颗粒与气泡的稳定性。添加捕收剂后,各粒级颗粒分选所需上升水流速度较为接近,各粒级精煤灰分在10%左右。

One of the challenges in the flotation is the top size of the particles. Application of three phase fluidized bed technology,introduction of air bubbles rising water flow,and comparison with and without air bubbles on the influence of coal particle bed expansion degree were used to conclude that the introduction of bubble flow can strengthen the flu- idization of low density particles. And,under three kinds of flow conditions including rising flow in rising water flow on- ly,rising bubble flow and water flow,and bubble flow+collector (kerosene),a coal separation experiment was carried out. Results show that the introduction of bubble flow can significantly reduce the rising flow required for the level of low density particles suspended velocity,the bubble flow’s influence on the level of low density particles is better than that on high density coal particles,the existence of the bubble strengthens the coal density,and weakens the effect of particle size on separation. Adding collection agent in the rising bubble flow,the low density particles and bubble form a particle-bubbles combination,low density particles can be separated in a low rise water speed,in a low speed upward water,its steady flow degree is low which can guarantee the stability of the large particles and bubbles. With the addi- tion of the collection agent,the speed of the water flow will be closer for each grain grade particle separation,and the ash of each grain grade will be about 10% .

WANG Dongdong,WANG Huaifa. Experimental study on the wide size coal particles in three phase fluidized bed[ J]. Journal of China Coal Society,2017,42(12):3305-3312.