Explosion method for open-cast mining underground goaf position

Abstract

The invention provides an explosion method for an open-cast mining underground goaf position. The general form of the goaf is primarily mastered by the goaf detection technology; according to the detected goaf form, through holes are formed in a top plate in the center of the goaf and the surrounding turning points to obtain the accurate goaf form; the thickness of the top plate and the inner height of the goaf are mastered; according to the thickness of the top plate and the inner height of the goaf, the through holes and the non-through holes of the top plate of the goaf and the whole section height blast holes around the goaf are designed on the top and the surrounding positions of the goaf; the explosive quantity of the holes of the goaf position is calculated and corrected, construction of hole distribution and explosive charging are carried out; the whole section height blast holes are charged according to the explosive quantity of the non-goaf position; the explosive in the surrounding boundary holes is firstly detonated; then, the explosive in the goaf holes are successively detonated. According to the explosion method for the open-cast mining underground goaf position, which is disclosed by the invention, the explosion effect is greatly improved, the explosion product satisfies the requirement of the next working procedure, the block rate is lowered by 80%, the foundation is reduced by 50%, the explosion effect of the non-goaf position is achieved, the explosion quality is subjected to qualitative leap, and the huge difficulty restricting the outdoor production is solved.

Description

technical field [0001] The invention belongs to the technical field of blasting, in particular to a method for blasting underground goafs in open-pit mining. Background technique [0002] Due to the Japanese underground mining of rich ore in history and the disorderly mining and poaching of mineral resources by private enterprises and private mines in the late 1990s, there are a large number of unknown underground goafs in open pits. When there is no detailed information on the mining status of the goaf (including mining height, mining area, etc.), and the goaf does not have the conditions for manual exploration, it will seriously affect the effect of open-pit mining. Especially when an unknown underground goaf is encountered in open-pit mining, it not only brings safety hazards to operators and equipment, but also causes the blindness of the drilling rig due to the uncertainty of the goaf, that is, the blind penetration of the hole depth (goaf) If the area penetrates, re-a...

AI Technical Summary

Problems solved by technology

When there is no detailed information on the mining status of the goaf (including mining height, mining area, etc.), and the goaf does not have the conditions for manual entry and exploration, it will seriously affect the effect of open-pit mining

Especially when an unknown underground goaf is encountered in open-pit mining, it not only brings safety hazards to operators and equipment, but also causes the blindness of the drilling rig due to the uncertainty of the goaf, that is, the blind penetration of the hole depth (goaf) If the area penetrates, re-arrange the holes to ensure that the next hole does not penetrate; the non-penetrating part can only be penetrated according to the normal hole, and it is not clear whether it meets the hole depth requirements), and the blind layout of the hole network causes the hole network to be uneven (due to The perforation position is uncertain. Once the unknown part penetrates and needs to be changed, the position of the original planned hole network will change even more)

The blindness, error and uneven distribution of holes seriously restrict the blasting work

For example, according to the existing technology, technicians calculate the single-hole charge amount and packing height for unpenetrated holes according to the conventional (production site without underground mined-out area) line charge density, and then select single-point initiation and multi-row The conventional detonation sequence of differential extrusion blasting in the large hole area is connected to the line blasting, without considering that due to the different hole depths and different resistance line sizes, each single hole needs to overcome different resistance lines and need to choose different charges and different materials. The filling height does not take into account the fact that the detonation sequence in which the hole in the empty area is detonated first will cause the roof of the empty area to collapse first and increase the difficulty of detonating the holes around the empty area (increase in the resistance line), which will result in multiple explosions due to the excessive resistance line. If the filling is too high, a large number of large blocks exceeding the standard will be formed. The roof of the empty area will collapse first, or the blast holes on the roof of the empty area will fly off, resulting in the failure of blasting in the surrounding holes of the empty area. The results of blasting the foundation (many foundations), blasting large pieces (high proportion of large pieces), and even the roof hanging in the empty area have further increased the difficulty of the shoveling and transportation process, resulting in a substantial increase in production costs. Consumption is 0.35~0.48 kg / t

How to solve the blasting technical problems such as the amount of blasting charge in the goaf, the filling height, the charge amount of each hole in different parts, and the sequence of blasting in the blasting area are the key issues to improve the blasting effect and overcome production and safety problems. Related reports on blasting technology in underground goaf in open-pit mining

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