磨料特性对磨料气体射流破煤影响的实验研究

Experimental study on influence of abrasive characteristics on coal breaking by abrasive gas jet

针对磨料气体射流,基于气固两相流理论分析影响磨料速度的因素,在一定喷嘴结构基础上,通过实验研究磨料特性对破煤效果的影响。通过理论分析发现,影响磨料速度的主要因素有磨料密度和磨料粒径。实验结果表明:在射流压力一定条件下,石英砂、石榴石和棕刚玉3种磨料中棕刚玉破煤深度最大,在80,120,200和280目4种不同目数磨料中,120目磨料破煤效果最优。通过分析磨料特性的影响,得出磨料硬度对破煤的影响最大,其次是磨料密度。开展磨料气体射流破煤实验,确定了磨料气体射流中最优射流靶距为70 mm,最佳破煤磨料为120目的棕刚玉磨料。

Aiming at the abrasive gas jet, the influence factors of abrasive velocity were analyzed according to the theory of gas - solid two - phase flow. The influence of abrasive characteristics on the coal breaking effect was studied by expe - riment on the basis of a certain nozzle structure. Through the theoretical analysis, it showed that the main influence factors of abra- sive velocity were the abrasive density and the abrasive particle size. The experimental results showed that under the same jet pressure, the depth of coal breaking was the largest for brown corundum among three abrasives, including quartz sand, garnet and brown corundum. The effect of coal breaking was the best for the abrasive with 120 mesh among four types of abrasives with different mesh number, including 80, 120,200 and 280 mesh. Through analyzing the influence of abrasive characteris- tics, it showed that the abrasive hardness had the largest influence on the coal breaking, and the secondly was the abrasive density. Through the experiments on coal breaking by abrasive gas jet, the optimum jet target distance was determined to be 7 cm, and the best abrasive for coal breaking was the brown corundum with 120 mesh in the abrasive gas jet.