Gas extraction method based on mining-induced fracture circular rectangular half-space zone

Abstract

The invention relates to a gas extraction method based on a mining-induced fracture circular rectangular half-space zone. By analyzing dynamic evolution characteristics, a mechanical mechanism and influence factors of the mining-induced fracture zone, the open-off cut side bandwidth is obtained and is about a first weighting interval, the working face side bandwidth changes within 2-3 times of a periodic weighting interval, the bandwidth near a wind inlet lane and the bandwidth near a wind return lane are about the 0.7-0.8 time of the first weighting interval, the height of an inner half-space face and the height of an outer half-space face are controlled by a key stratum position and the deformation, fracture and instability states of a formed masonry beam structure, accordingly, arrangement parameters of end points of mining-induced pressure relief gas extraction drill holes are determined, the field effect test shows that as the gas extraction drill holes are formed in the mining-induced fracture circular rectangular half-space zone, the gas extraction concentration is improved greatly, synchronized advancement of coal mining on a working face and continuous pressure relief gas extraction is achieved, the mechanism of mining coal and gas together at a high-gas coal seam is obtained, and the gas extraction method based on the mining-induced fracture circular rectangular half-space zone is formed.

Description

technical field [0001] The invention relates to the field of mine safety engineering technology (gas drainage technology), in particular to a gas drainage method based on circular-rectangular terraces in mining cracks. It is applicable to the determination of gas drainage drilling parameters in the production process of high-gas coal mines in my country, which greatly improves the gas utilization efficiency in the production process of coal mines and reduces the probability of gas accidents. Background technique [0002] The coal seam occurs underground, and its upper overlying rock is an orderly combination of a series of rock layers, and one or several relatively hard thick rock layers in the layered combination play a major role in controlling the deformation and destruction of the entire overlying rock mass. This hard stratum is called a key stratum, and most overburdens have more than one key stratum. After the coal seam is mined, the overlying strata will undergo defl...

AI Technical Summary

Problems solved by technology

However, in the implementation process, the determination of drilling parameters for gas drainage is still at the level of judgment based on experience.

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