Method for mining coal through cooperation of crack filling and remained coal seam in uplink re-mining tool post remnant mining region

Abstract

The invention belongs to the technical field of coal mining and discloses a method for mining coal through the cooperation of crack filling and a remained coal seam in an uplink re-mining tool post remnant mining region. The method comprises the following steps: prospecting and finding out the distribution condition of a tool post remnant mining region below an overhead coal seam, and determiningthe position of a rock-covered main key layer; tunneling a transportation drift and a wind return drift along a base plate of the overhead coal seam; respectively vertically tunneling one-open-end drifts at an interval of 90m-120m in the transportation drift and the wind return drift, and forming inlet wells towards the tool post remnant mining region on the lower side along the base plate of theoverhead coal seam in the one-open-end drifts; (S4) simultaneously pouring slurry into the tool post remnant mining region from the inlet wells until the tool post remnant mining region is full; (S5)after the poured slurry is hardened to acquire carrying capacity, forming fracture drill holes from the surface of the ground right above each one-open-end drifts towards the main key layer, and pouring water through the fracture drill holes so as to fracture the main key layer; and (S6) distributing a working plane of the overhead coal seam, and carrying out uplink mining. The invention is suitable for the safe mining of the overhead coal seam covering the tool post remnant mining region.

Description

technical field [0001] The invention belongs to the technical field of coal mining, and in particular relates to a coal mining method combining crack filling and upward re-mining of the remaining coal seam in the residual mining area of ​​the knife column, which is mainly suitable for safe mining of the overlying empty coal seam in the residual mining area of ​​the knife column. Background technique [0002] Restricted by backward support technical conditions in the past, and faced with the problem of hard roof control, mining areas such as Datong, Changzhi, and Yangquan widely used the knife pillar coal mining method from the 1950s to the 1990s. Advance 20-30m and leave 5-10m knife column coal pillars to support the overlying strata. The application of this method, on the one hand, has a low resource recovery rate, and on the other hand, due to the stress concentration at the coal pillar of the cutter column, it brings serious challenges to the safe mining of the adjacent u...

AI Technical Summary

Problems solved by technology

However, the upward mining of the cutter column goaf is a dynamic process. The advancement of the upward working face will inevitably cause the redistribution of the mining support pressure, resulting in further concentration of the stress of some cutter column coal pillars. In extreme cases, it may cause local cutter column coal pillar instantaneous Instability and damage are extremely unfavorable to upward mining

Images