Thin basic rock shallow buried coal seam longwall face water-retaining mining method

Abstract

A water-retaining mining method for longwall working faces in shallow coal seams, especially suitable for safe production and water resource protection in shallow coal seams. The mining working face is determined according to coal seam geological survey information data; large-scale long-wall working faces with a working face length of more than 200m are used as much as possible. Wall working face; the working face is supported by high-strength hydraulic supports above 8000kN; suitable supporting equipment for rapid advancement of the longwall working face is selected, and cycle operation is adopted to ensure that the daily advancing speed of the longwall working face is above 15m; Local filling or partial reduction of mining height in the vicinity of 10-50m to reduce the penetration of cracks in the mining overlying rock, so that the bedrock will not undergo overall dislocation failure; Reduce the mining height or local grouting within the corresponding range of influence on the surface to reduce the migration space of the overlying rock, so that the overlying rock forms a relatively stable masonry beam structure, and enhances the water blocking effect of the mined overlying rock. The method has good water resource protection effect, can produce safely, reduces waste, is environmentally friendly, and has a high recovery rate of coal resources.

Description

technical field [0001] The patent of the present invention relates to a water-retaining mining method for longwall working faces of thin bedrock shallow buried coal seams, especially suitable for safe production of shallow buried coal seams, protection of water resources in mining areas, ecological environment construction and improvement of coal resource recovery rate, especially for bedrock Shallow coal seams whose thickness is more than 10 times the mining height. Background technique [0002] The Shenfu-Dongsheng coalfield in the west of my country is located in the northern part of Shaanxi and the southern part of Inner Mongolia, with proven reserves of 223.6 billion tons, accounting for about 1 / 3 of the country's proven reserves. Production base. Since the coalfield is located on the edge of the Mu Us Desert, the thickness of the overlying loose layer is relatively large, ranging from 0 to 76.33m, with an average of 32m, and there is a large amount of phreatic water. T...

AI Technical Summary

Problems solved by technology

At the same time, in the process of mining shallow coal seams, many coal mines have experienced safety accidents such as roof infiltration, water infiltration and sand intrusion, which affect normal safe production. The problem of water retention and anti-collapse coal mining has always been a typical problem in the development of shallow coal seams in western my country.

However, for shallow coal seams where the bedrock thickness is more than 10 times the mining height (the bedrock thickness is generally greater than 50m), if the above-mentioned coal mining method is still used, the waste of coal resources will be very serious, which is a major problem that needs to be solved urgently on site