Study On The Structural Control Characteristics Of Gas Occurrence And Application In Kongzhuang Coal Mine

Coal and gas outburst accident is the most important factor that restricts the safe production of coal mine.The mechanism of coal and gas outburst is so complicated and the influencing factors are so many that it cannot be predicted accurately at present.The most important prerequisite for coal and gas outburst is the presence of a large amount of gas in the coal.The gas content of coal seams in most mining areas in China is generally high,among which the gas content of deep coal seams is higher.In the process of the project,it is found that the gas content of deep coal seams of kongzhuang coal mine in datun mining area is relatively lower than that of the deep coal seams in its adjacent mining area Huaibei mining area through on-site measurement.In this paper,the gas geological condition of Kongzhuang coal mine is analyzed based on the regional geological structure characteristics,the sedimentary evolution characteristics of coal-measure strata,the characteristics of coalbed methane accumulation and the law of gas occurrence.In the process of geological structure evolution,the region where Kongzhuang coal mine is located is affected by multi-stage tectonic movement,which made the coal seam gas content far lower than the adjacent Huaibei mining area.In this paper,the gas bearing difference of Shandong mining area,Datun mining area and Huaibei mining area was analyzed from the stratigraphic difference and the stratigraphic uplift and subsidence difference.Four coal samples are selected in this paper from?3 and?5 mining area.Combined with the industrial analysis of coal,the sturdiness coefficient,the initial velocity of gas emission,the adsorption and desorption characteristics and the pore characteristics.The f values of coal samples from gongzhuang coal mine were 0.955,0.930,0.574 and 0.533,respectively.^?p were 4.5 mmHg,5.5 mmHg,11.2 mmHg and 11.5 mmHg.The adsorption constants were 16.8817 m³/t,17.1490 m³/t,17.9966m³/t and 21.6372 m³/t.The maximum BET specific surface area was 0.933 m²/g and the maximum micropore capacity was 0.02 ml/g.The experimental data show that the outburst risk of the?5 mining area is greater than that of the?3 mining area.According to the calculation of volatile fraction,the average maximum reflectance range of vitreous group of coal in Kongzhuang coal mine is 0.66⁰.84,and the type of coal is gas coal,fat coal and 1/3 coking coal.The experimental results show that the coal seam gas capacity is poor,the gas adsorption capacity is poor,the gas occurrence space is small and the outburst risk is low.Through the summary and analysis of the original data such as gas pressure/content and gas emission volume at different elevations in several mining areas,combined with field-measured data.Using multiple linear regression equation of Kongzhuang coal mine gas content and to forecast the gas emission,and draw the corresponding contour map,as well as the gas weathered zone division.Through the theoretical prediction and actual measured values of contrast analysis,the results show that?5 mining area exists abnormal gas occurrence area,presents the characteristics of"high pressure,low levels".Combining the gas occurrence law of the mining area?5 of Kongzhuang coal mine and the actual situation on the spot.In order to achieve the purpose of effectively controlling the gas occurrence abnormal area in the mining area,the roadway excavation period,the coal mining face of the mining area and the mining face Partial treatment measures during the mining period,supplemented by strengthened management to ensure safe and efficient production of the mine.