Flexible shield support excavation integrated supporting coal-pillar-free mining method of steep medium-thickness coal seam

Abstract

The invention discloses a flexible shield support excavation integrated supporting coal-pillar-free mining method of a steep medium-thickness coal seam. Flexible shield supports the same as those on a working face are used in a section drift for supporting; flexible shield supports of a section air return drift above the working face are naturally transited into the working face; flexible shield supports in the working face are naturally transited into a goaf below the working face to be maintained into a section transport drift which serves as an air return roadway of a lower section; the section air return drift is not tunneled any longer during recovery of the lower section; at the same time, a procedure of mounting and removing the flexible shield supports on the working face is canceled; mounting and removal of chambers and roadways related to subsidiary transport on the working face are canceled; the workload is reduced; the yield is increased; the advance speed of the mining working face is increased; normal replacement between the upper and lower sections is ensured; section coal pillars are canceled; a recovery ratio is increased; the natural fire danger in the goaf is reduced; and a reliable safety assurance is provided for the recovery work.

Description

technical field [0001] The invention relates to a coal mining method, in particular to a coal mining method with integrated support and no coal pillar for mining with a flexible cover support in a steeply inclined medium-thick coal seam. Background technique [0002] At present, there are few formal coal mining methods for steep slopes in the country, and the applicable conditions are very limited. Pseudo-inclined flexible cover support mining method is the preferred mining method for steeply inclined medium-thick coal seam mining. The pseudo-inclined flexible cover support coal mining method is suitable for steeply inclined coal seams with a coal seam dip angle of 40-90°, stable burial, and little change in coal seam thickness. In 1966, the Huainan Mining Bureau successfully used the pseudo-inclined flexible cover support coal mining method for the first time, and since then the pseudo-incline flexible cover support coal mining method has been promoted nationwide. In 1981...

AI Technical Summary

Problems solved by technology

[0013] This coal mining method also has certain limitations:

[0014] (1) Sectional coal pillars are left in the goaf, and the loss of coal pillars is about 30%. These coal pillars affect the recovery rate of the working face, and the coal pillars in the goaf are prone to spontaneous combustion

[0015] (2) The installation, evacuation and auxiliary transportation of the mining face require special tunnels. The construction of these tunnels increases unnecessary workload and affects the progress of mining, which in turn makes the working face yield lower

[0016] (3) The safety of coal-sliding holes and connecting inclined lanes is poor, which threatens the safety of workers in the process of pedestrians and transporting cover supports

[0017] (4) There is support pressure above the coal pillar, which makes the roof move irregularly, and it is easy to generate impact load

[0018] (5) At present, it is still difficult to realize mechanized operation on the working surface, and the labor intensity of workers is high

However, the workload is heavy, and the requirements for roof management are very strict. Due to safety factors, the country canceled the storage coal mining method at the end of 2008.

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