Mining area coal-pillar-free mining method

Abstract

The invention discloses a mining area coal-pillar-free mining method. The mining area coal-pillar-free mining method comprises the following steps that (1) partitioning, specifically, one wing of a mining area is divided into a first section and a second section; (2) tunneling, specifically, tunneling operation is conducted in the first section and the second section simultaneously, and each tunneling operation comprises tunneling of a rubber conveying gate road and a return air gate road, mining of coal pillar coal bodies between the rubber conveying gate road and the return air gate road and supporting and filling operation of a coal pillar open-roof area which are conducted alternately; and (3) stoping, specifically, stoping operation is conducted in the first section and the second section alternately. The mining area coal-pillar-free mining method has the advantages that the mining area coal-pillar-free mining method can be used for mining of thin coal seams, medium-thickness coal seams and thick coal seams, and no rigid requirement for lithology of coal seam roofs and coal seam floors exists; coal pillar recovery and concrete filling operation are completed alternately during tunneling of the rubber conveying gate road and the return air gate road, and the influence of large-area and high-stress mining dynamic pressure accompanying the mining process of a fully mechanized coal mining face is avoided; and concrete filling pillars are good in integrity and high in bearing performance.

Description

Technical field: [0001] The invention relates to the technical field of coal mining, in particular to a coal pillar-free mining method in a mining area. Background technique: [0002] In the existing underground coal mines, there are two main types of coal pillar-free mining in the mining area: [0003] The first is the roof cutting method, that is, a certain distance ahead of the coal wall of the fully mechanized mining face, and in advance in the rubber transportation channel roadway of the fully mechanized mining face, close to the side of the coal wall, a deep hole is drilled into the roof and the method of blasting and roof cutting is adopted. Pre-split the roof, or use special equipment to cut the roof, so that the roof of the rubber transportation trough and the roof of the fully mechanized mining face are no longer a whole; during the continuous advancement of the fully mechanized mining face, the roof of the gob continues to collapse; due to The roof of the rubber ...

AI Technical Summary

Problems solved by technology

[0005]However, there are following problems in adopting the above two mining methods without coal pillars: First, the mining dynamic pressure is strong during the mining of the above two methods, which will affect the coal seam top and bottom slate There is a high requirement for the performance of coal seams; and the influence of mining dynamic pressure on medium-thick coal seams is smaller than that of thick coal seams, and it is mostly used for mining medium-thick coal seams, not suitable for thick coal seams; in addition, the above two methods are suitable for the integrity of roof and floor lithology Good and stable coal seam, therefore, the applicable conditions of the above two methods are relatively harsh, and the universal applicability is poor;

[0006]Secondly, in the above two methods, after mining the fully-mechanized mining face on the side of the rubber transportation channel, due to the impact of mining dynamic pressure, it is necessary to The rubber transportation trough is strengthened for maintenance, and the remaining rubber transportation trough needs to be used as the return air trough of the next fully mechanized mining face adjacent to it. When the next fully mechanized mining face is recovered, it will still be subject to The influence of dynamic pressure; therefore, the requirements for the support strength of rubber transport along the channel are very high, and the requirements for the selection of roof support materials are higher, resulting in very high support costs and labor intensity;

[0007]Thirdly, in the current mining process of the working face, the side coal body on the side of the goaf is mined along the rubber transportation channel, and then the precast concrete wall is used to The reserved space is isolated from the goaf, and the roadway is reserved along the goaf; however, due to the slow progress of the fully mechanized mining face, after the coal is mined, it will take 3-6 months or longer for the rock formation above the goaf It will gradually stabilize after a period of time. During this period, the concrete wall has to bear the influence of the roof pressure and the dynamic pressure of the fully mechanized mining face before reaching the design strength after the concrete wall is built. As a result, the bearing effect of the cast-in-place concrete wall will be greatly affected. Influence;

[0008]Fourth, after the roadway is left along the goaf, the isolation formed by the direct roof of the goaf needs to be reinforced and sealed by spraying grout. The roof of the roadway still needs secondary support for maintenance, which complicates the on-site operation process and greatly increases the labor intensity; seriously affects the advancement speed of the fully mechanized mining face, and has a significant impact on the normal production organization of the fully mechanized mining face;

[0009]Fifth, after the roadway is left along the goaf, the surrounding rock deformation is obvious, and the maintenance cost of the roadway in the later period is relatively high. Due to the influence of dynamic pressure, the required reinforced support strength is higher;

[0010]Sixth, with the continuous advancement of the fully mechanized mining face, the isolation and cast-in-situ concrete walls formed by direct roofing in these two pillarless mining technologies are both Under the continuous impact of mining dynamic pressure, there are still cracks between the isolation formed by the roof connection. During the solidification of the cast-in-place concrete wall, it is also affected by the mining dynamic pressure, resulting in poor integrity, many cracks and small width; Air leakage in the goaf and relatively poor spontaneous combustion ability in the goaf are also not conducive to isolating water accumulation in the goaf, resulting in a relatively poor mining operation environment in the fully mechanized mining face

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