Parallel operation coal mining method of pressure relief gas drainage and top coal caving in huge thick and hard coal seam

Abstract

The invention discloses a parallel operation coal mining method of pressure relief gas drainage and top coal caving in a huge thick and hard coal seam, and belongs to the technical field of top coal caving mining. The parallel operation coal mining method comprises the steps that a top coal caving working face is arranged along the bottom of the huge thick and hard coal seam, a lower connection roadway and an upper connection roadway are separately arranged in an inclined mode from a transportation roadway of the top coal caving working face and a return airflow roadway of the top coal cavingworking face to reach the top of the huge thick and hard coal seam; a group of high order position process roadways which are arranged in parallel are drilled at the top of the huge thick and hard coal seam at intervals, and a connection roadway penetrates through the high order position process roadways; adjusting air windows are arranged in the connection roadway to control ventilation, high order position gas drainage pipes and drill sites are arranged in the high order position process roadways, and the drill sites are used for construction of drilling downwards; and liquid carbon dioxideblasting generators are arranged in boreholes, and the carbon dioxide blasting generators are arranged ahead of the top coal caving working face. According to the parallel operation coal mining methodof the pressure relief gas drainage and the top coal caving in the huge thick and hard coal seam, safe mining of the working face is realized, and the production efficiency is high; and at the same time, liquid carbon dioxide is used for blasting, the blasting process is intrinsically safe, and the migration and drainage of gas to the high order position process roadways is facilitated.

Description

Technical field: [0001] The invention relates to the technical field of top-coal caving mining, in particular to a coal mining method for parallel operation of top-coal caving for pressure relief and drainage of huge thick hard coal seams. Background technique: [0002] The geological conditions of my country's coal seams are complex. As a high-yield and efficient mining technology, top-coal caving mining has been popularized and applied to a certain extent. However, the low coal recovery rate of the top-coal caving mining method and the difficulty of gas control in the working face are the constraints that affect its development. Especially when the top coal caving is mined under the condition of extremely thick and hard coal seam, the problem is particularly prominent. [0003] At present, the technical methods of coal seam enhancement and pressure relief proposed by domestic scholars mainly include explosive deep hole pre-splitting blasting, hydraulic fracturing, hydraulic...

AI Technical Summary

Problems solved by technology

Due to the defects of some anti-reflection technologies and process methods, the effect of many technical measures is not ideal

[0004] Patent document CN201610263144.5 discloses a method for caving top-coal in weakened hard coal seams based on carbon dioxide blasting, which uses carbon dioxide blasting to weaken the hard top-coal, so that the top-coal release rate is increased by 20% to 30% compared with that before roof fracturing , but the drilling at the roof between the two hydraulic support beams near the coal wall has a greater impact on the production of the working face

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