A gas drainage method for low-level and multi-stage through-bed drilling holes for coal-rock interbedded coal seams

Abstract

The present invention relates to a low-level multi-stage perforated drilling method for gas drainage in coal-rock interbedded coal seams. (Right) A 0.3-1m slope downhill (3) penetrating into the bottom rock layer (2) of all coal-rock interbeds (2) is constructed on the side of the slope, and a length × width × height = 3.0m × 2.5m × 2m low-level drilling site (4), in which several low-level multi-stage through-layer drilling holes (5) are constructed obliquely upward along the roadway excavation direction to the mining layer, and inserted into multiple Step bushings (6‑1), (6‑2), (6‑3), use Ф120mm rubber hose (11) to connect the bushings (6‑1) with multi-pass, and connect with the gas pump in the roadway The mining pipelines (12) are connected and converged, and the low-level multi-stage cross-layer drilling (5) is connected to the gas extraction operation. The invention effectively drains the coal seam floor gas, is safe and efficient, and can be used for the implementation of outburst prevention measures on the working face.

Description

technical field [0001] The invention relates to a gas drainage method for low-level multi-stage perforated drilling holes in coal-rock interbedded coal seams. Background technique [0002] my country is a country where coal is the main energy source. At present and in the next 20 years, coal will still account for a large proportion of my country's primary energy structure. Coal and gas outburst is an extremely complex phenomenon of gas dynamic disaster, which is extremely sudden and destructive. According to statistics, in 2010, there were 2,197 high-gas mines in my country, accounting for 17% of the national coal mines, and 1,044 coal and gas outburst mines, accounting for 8.1% of the total number of coal mines in the country. Mine gas disasters have become the number one killer of coal mines. seriously affect the safety production of coal mines. my country is one of the countries with the worst disasters in the world. In-depth understanding of the law, characteristics a...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the characteristics of coal-rock interbedded coal seam roadway excavation and mining of the working face, the amount of abnormal gas emission at the bottom is large, and it is difficult to drill holes for gas drainage on the negative slope of the working face when the construction is inclined downward. Drill sticking, clamping, and easy hole collapse after the drilling is withdrawn make it impossible to construct long-distance drilling, and it is difficult to eliminate the danger of coal and gas outburst during roadway excavation and working face mining. Through the implementation of low-level multi-level penetration Borehole gas drainage eliminates the risk of coal seam area (or local) outburst, improves the efficiency of fully mechanized roadway excavation, and solves the problem of coal seams with interbedded coal seams during roadway excavation and working face recovery. , the problem that gas is difficult to control, the present invention provides a coal-rock interbedded coal seam anti-outburst gas extraction method for low-level multi-stage through-bed drilling

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