压实度对无底柱分段崩落法放矿效果的影响

Influence of Compaction Degree on Ore Drawing Effect of Non-pillar Sublevel Caving Method

无底柱分段崩落法因具有生产成本低、结构简单、安全程度高等优点而被广泛应用,但是该方法的放矿工作是在松散矿岩的覆盖条件下进行的,崩落矿岩散体因受到爆破及上覆岩石的挤压而产生不同的压实度,上覆岩石的厚度不同导致下部矿石的压实度不同,进而导致出矿过程中放矿效果受到影响。为研究压实度对无底柱分段崩落法放矿效果的影响,采用单分段、单进路物理放矿模型,对不同压实度所产生的放矿效果进行了研究。结果表明:放出纯矿石量、累计废石混入率以及矿石回采率随压实度的减小呈现规律性变化;适当改变矿石的压实度,散体之间的结构会向有利于放矿的方向改善,增加纯矿石的放出量,降低废石混入量,提高矿石的回采率。

Non-pillar sublevel caving method is widely used because of its low production cost, simple structure and high safety. However, the ore drawing work of this method was carried out under the condition of overlying loose ore rock. The bulk of the caved ore rock has different compaction degrees due to blasting and the extrusion of the overlying rocks. The different thickness of the overlying ore rock leads to different compaction degrees of the lower ore, which in turn affects the ore drawing effect during the ore drawing process. In order to study the influence of compaction degree on the ore drawing effect of non-pillar sublevel caving method, the ore drawing effects with different compaction degrees were studied by using physical ore drawing model with single sublevel and single approach. The results show that the amount of pure ore, cumulative mixing rate of waste rock and the ore mining rate change regularly with the decrease of compaction degree. By appropriately changing the compaction degree of the ore, the structure among the particles will be improved in the favor of ore drawing, thus increasing the amount of pure ore drawing, reducing the amount of mixed waste rocks, and increasing the ore mining rate.