Stripped fluid expansion filling mining method for below middle thick coal seam

Abstract

The invention which relates to a stripped fluid expansion filling mining method for a below middle thick coal seam belongs to the filling field of coal mining. The method is suitable for the coal seam with the thickness of below 2m. According to the method, a coal-mining working face and a production system thereof are arranged according to a long-wall back-mining technology, and the caving strap width and the filling strap width are respectively determined on the basis of a coal seam main roof initial caving span and a key layer theory according to principles that the caving strap width is less than the safe strap of the key layer or the composite key layer and the filling strap width is less than the main roof initial caving span; a fluid expansion material is used to fully fill the gob of the filling strap; and the filling body is used to control the movable deformation of a rock layer on the filling strap, and the key layer or the composite key layer is used to control the movable deformation of the rock layer on the caving strap. Compared with various present long-wall filling mining technologies which use materials of spoil, pastes and the like to fill, the method of the invention allows the land face settlement to be controlled in an allowable minimum degree, so the recovery rate of the mining field is substantially improved.

Description

technical field [0001] The invention relates to a strip-type fluid expansion filling and mining method for coal seams below medium thickness, which is suitable for coal seams with a thickness below 2 meters and belongs to the field of coal mining and filling. Background technique [0002] At present, the filling and mining methods adopted by the coal industry can be summarized as follows: first, according to the type of filling material, it can be divided into four types: water and sand, gangue, fly ash, and tailings; second, according to the physical form of the filling material, It can be divided into four types: solid, paste, paste-like, and fluid; the third is according to the mining technology of the coal mining face, it can be divided into three types: longwall, strip, and roadway; the fourth is according to the transportation method of filling materials , can be divided into two types: mechanical and artesian. The key elements for evaluating the filling effect mainly...

AI Technical Summary

Problems solved by technology

These methods, firstly, because the full filling (that is, complete roofing) cannot be realized in the vertical direction, although the surface subsidence brought about by the mining of the coal seam can be effectively controlled, it is difficult to control it within the minimum allowable degree; Because the filling material is conveyed mechanically, there are many unfavorable factors such as complex filling process, high operating cost, and low filling efficiency.

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