A method to determine the pre -exhausting gas bandwidth of the coal mining of the coal mine

Abstract

The invention relates to a method for measuring the widths of the tunnel gas pre-discharge zone of a coal mine working face.The method is characterized in that in a mining-area tunnel closest to the working face, 5 gas injecting holes are constructed starting from a position 10m away from a crossheading entrance, the depths of the holes are respectively 40m, 35m, 25m and 20m, and cement is injected into the holes to seal the same; tracer gas SF6 is injected into the gas injecting holes, measuring is continuously performed for 300 days at the 5 testing points through SF6 testers, and the widths of the tunnel gas pre-discharge zone of the coal seam of a coal mine at different tunnel exposure time are obtained according to the relation graph of measured data.The method has the advantages that the blank of the method for measuring the widths of the tunnel gas pre-discharge zones of different coal mines at different coal seam tunnel exposure time is filled up, the features of stable diffusion and easiness in capture of the tracer gas SF6 are utilized, the widths of the coal seam tunnel gas pre-discharge zone are measured accurately while the normal production of the coal mine is unaffected, the method is simple to operate, low in cost, capable of measuring the widths by the technical capacity of the coal mine, and quite good in economical efficiency and universality.

Description

technical field [0001] The invention relates to the field of prediction of gas emission in a coal mine mining face, in particular to a method for measuring the width of a roadway pre-discharging gas belt in a mining face. Background technique [0002] Gas prevention technology in coal mine mining face includes two aspects: gas emission prediction and gas drainage. Only by judging the different sources and quantities of gas through gas emission prediction can gas drainage be effectively guided. The main sources of gas in the production process of the coal mining face are: the local coal seam, adjacent layers and surrounding rocks, among which the gas in the local coal seam is the main source that affects safe production. Coal mines must predict the amount of gas emission in the coal seam before mining, so as to carry out targeted gas drainage measures. [0003] China's coal mines adopt the national standard "Coal Mine Gas Emission Prediction Specification" (AQ1018-2006) for ...

AI Technical Summary

Problems solved by technology

China's coal mines are widely distributed, and the coal formation and occurrence conditions of coal are very different. Since there is no way to directly measure this parameter, we can only use different coal qualities to estimate the width of the roadway pre-drainage gas belt, which leads to the predicted value of gas emission in this coal seam. large error

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