A charging system for advanced rock breaking in open-pit mines

Abstract

The invention discloses a charge system for advance rock breaking of a surface mine. The designed blast hole depth L=H / sin alpha'+ h / sin alpha'+ delta h / sin alpha', wherein H is the height of open-air stages, alpha' is the dip angle of blast holes, h is the extra depth, and delta h is the increased depth. An advance primer cartridge (3) and an advance primer detonator (4) are arranged at the blast hole deepened position at the bottom of each blast hole, and the lower portion of each advance primer detonator (4) is located at the position 1 / 4 of the upper portion of the corresponding advance primer cartridge (3). An isolation section (5) is arranged at the blast hole deepened position of each blast hole (2). A main primer detonator (7) is located at the position 1 / 4 of the lower portion of each main charge (6). The in-hole micro-delay detonation technology that the advance primer cartridges (3) and the main charges (6) on the upper portions carry out detonation in sequence is adopted so that advance pre-damage of rock on the upper portions of the stages can be achieved, and the situation that the perforating and blasting work of the lower stages is influenced by excessive breaking of the rock can be effectively avoided.

Description

technical field [0001] The invention belongs to the technical field of blasting engineering in open-pit mines, and in particular relates to a blasting charge structure system, which is suitable for the early crushing of the rock mass at the top of the blast hole during step blasting in open-pit mines, so as to effectively reduce the large-block rate of blasting and significantly improve the blasting The effect is to reduce the cost of mining. Background technique [0002] Deep hole blasting is an important production process in open-pit mines. In the composition of ore costs, blasting costs account for about 15% to 20% of mine production costs. The quality of blasting directly affects the efficiency of mining, shovel loading and transportation operations. If the blasting large block rate is too high, it will increase the amount of secondary crushing and increase the cost of ore mining. [0003] High chunk rate in deep hole blasting is a common problem in open-pit mines. In...

AI Technical Summary

Problems solved by technology

However, the charging procedure is complicated and difficult to implement, which affects the improvement of production efficiency.

In addition, for the large pieces after blasting, hydraulic excavators and breakers are usually used for secondary crushing, which not only has low crushing efficiency, but also increases the cost of ore mining, which directly affects the economic benefits and production safety of the mine.

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