Goaf grouting treatment method for re-mining of old goaf of extra-thick coal seam

Abstract

The invention relates to a goaf grouting treatment method for secondary mining of an old goaf of an extra-thick coal seam. The method comprises the following steps: step 1, determining a plane boundary of a re-mining area; 2, calculating and determining a re-mining treatment vertical boundary; 3, determining the layout mode of ground directional drilling and underground drainage drilling, the probing layer position, the horizontal distance, the construction sequence and the drilling structure requirement; 4, parameters such as grouting materials, pressure, ending standards, grouting sequences and cooperation of grouting and drilling under different working conditions are determined; and 5, checking and reinforcing the grouting filling effect. The method effectively solves the problem of safe and efficient mining of multiple disasters such as water disasters, fire areas, harmful gases and broken roofs confronted by re-mining of residual coal in the extra-thick coal seam in a non-standard mining mode in the prior art, good effects of multi-disaster-source disaster control, space filling and coal rock consolidation in a re-mining area are achieved, and favorable conditions for safe mining are created for re-mining of residual coal in the extra-thick coal seam.

Description

technical field [0001] The invention relates to a method for controlling gobs through grouting in directional drilling areas to realize re-mining of extra-thick coal seams, belongs to the technical field of mine safety, and in particular relates to a gob grouting method for re-mining old goafs of extra-thick coal seams. Pulp management method. Background technique [0002] The re-mining of the extra-thick coal seam left coal area is faced with the threat of serious disasters such as water accumulation in the goaf, coal seam fire, harmful gas enrichment, and roof breakage. It has the characteristics of complexity, concealment, and uncertainty. The existence of the problem will seriously restrict the safe and efficient production in the coal-remaining area. [0003] At present, there are many treatments for gobs at home and abroad, usually based on grouting filling, and the main purpose of treatment is to ensure the stability of the foundation and prevent ground deformation a...

AI Technical Summary

Problems solved by technology

[0004] 1) The scope of grouting filling in the goaf is small, mainly in small areas such as linear and point-shaped areas, and the re-mining area of ​​the leftover coal area cannot be realized, and the re-mining area cannot meet the requirements of re-mining

[0005] 2) The method of grouting filling in the goaf is single, mostly straight holes on the ground, and the diffusion radius of grouting filling is limited. If the range of the gob is large, the comprehensive treatment project needs to evenly arrange the drill holes from the ground, and the drill hole spacing is generally 30m , large amount of work, high cost

[0006] 3) The grouting filling is mostly aimed at achieving ground subsidence reduction and grouting reinforcement, without considering the distribution of goafs, water damage, fire areas, gas and other disasters that must be faced in re-production. Relevant technologies for re-mining regional governance of leftover coal in thick coal seams

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