A coal mining method for pre-mining layered and broken top coal in the middle of extra thick coal seam

Abstract

The invention provides a coal mining method for pre-mining layered broken top coal in the middle of an extra-thick coal seam, belonging to the field of coal mining. The method includes firstly arranging a longwall working face in the middle of the coal seam for pre-mining a 3-7m coal seam, then the coal body in the upper part of the coal seam is fully broken under the action of mine pressure and gravity, and the broken coal body falls on the unmined coal body in the lower part of the coal seam; In the future, reserve 2-3m top-coal at the lower part of the coal seam to arrange fully-mechanized caving working face for top-coal caving mining. The height of coal cutting is generally 3-5m, and the reserved 2-3m top-coal and broken caving The coal body in the upper part of the coal seam is released at the coal outlet of the hydraulic support of the fully mechanized caving face at the lower part of the coal seam, and is transported out of the working face by the conveyor behind the support. The thickness of the coal seam can reach 40m at one time. The method of the invention gives full play to the advantages of fully mechanized mining and fully mechanized caving mining, has the advantages of less layering, low roadway excavation rate, high recovery rate, and less times of moving and reversing the working face, and has important guidance for safe and efficient mining of extra-thick coal seams significance.

Description

technical field [0001] The invention belongs to the field of coal mining, and in particular relates to a coal mining method for pre-mining layered and broken top coal in the middle of an extra-thick coal seam. Background technique [0002] The occurrence of extra-thick coal seams in my country occupies a certain proportion, especially with the development of resources in western regions such as Xinjiang, the proportion of mining of such coal seams will gradually increase. For the mining of extra-thick coal seams, downward layered mining or upward filling mining are generally adopted. Upward mining currently adopted is aimed at short-distance coal seam groups. The tried-and-tested upward sequential coal mining method with thick coal seams layered and constant bottom has problems such as broken roof, severe mine pressure, and easy roof fall. The application is relatively limited. There is no other upward mining technology with wide applicability in a single thick coal seam. ...

AI Technical Summary

Problems solved by technology

Upward mining currently adopted is aimed at short-distance coal seam groups. The tried-and-tested upward sequential coal mining method with thick coal seams layered and constant bottom has problems such as broken roof, severe mine pressure, and easy roof fall. The application is relatively limited. There is no other widely applicable upward mining technology for a single thick coal seam

Although upward filling mining can realize the mining of extra-thick coal seams, the cost of filling materials is high, and the number of layers in these two methods is large, the number of times of moving and reversing is large, and the work efficiency is low

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