露天矿爆破扬尘规律及水炮泥配比优化

Blasting-dust diffusion rule and water stemming ratio optimization for open-pit mine

为简单有效解决露天矿台阶爆破产生的粉尘污染问题,解决目前大多数露天矿台阶爆破水炮泥使用效率不够理想的现状,研究爆破扬尘机理和水炮泥-固体炮泥最佳配比.以抚顺露天矿台阶爆破为工程背景,运用气固两相流及爆炸力学理论,采用Fluent软件数值模拟与现场测试相结合的方法,实现对爆破扬尘污染的实时模拟.研究结果表明:冲击运动阶段及蘑菇云形成阶段,爆生气体急速膨胀,大量的粉尘在爆破冲击动能的作用下,冲入开放的大气空间,随后扩散阶段,粉尘在无风条件下运移速度很低.粒径60~100μm的粉尘沉降缓慢,粒径在40μm以下粉尘由于受风流扰动强烈,自然沉降困难.推导出水炮泥-固体炮泥配比公式,既满足爆破效果的要求,又达到良好的降尘效果.

In order to reduce the pollution resulting from the blasting dust in a simple and effective way, and improve the dust suppression efficiency of water stemming for the most open-pit mine bench, the blasting dust diffusion law and the optimal ratio between water-stemming and solid stemming were studied. According to the theory of gas-solid two- phase flow and explosion mechanics, and by using Fluent numerical simulation combined with field test, the real-time simulation of blasting dust pollution was realized. The analysis results show that in the impact movement stage and mushroom cloud formation stage, the blasting air rapidly expands, and a large amount of blasting dust spreads into the open air space. The dust slowly sinks, whose particle size is 60-100 pro, and the dust whose particle size under 40 grn sinks very difficultly and continues to stay in the air due to wind disturbance. The water-stemming and solid stemming ratio formula was attained, meeting the requirements of both blasting effect and the idea suppression efficiency.