Research on Spatiotemporal Evolution Law of Developed Coal Seam Gas Drainage in Concealed Structures

In order to solve the challenges of low efficiency, long extraction cycle, and easy occurrence of coal and gas outbursts in developed coal seam gas drainage of deep concealed structures, taking the 29060 machine roadway bottom pumping roadway of Xuehu Coal Mine as the research object. Through monitoring parameters such as gas concentration, extraction negative pressure, standard condition extraction pure flow rate and others for 94 days from April 29 to July 31, 2024, the extraction data at different spatial locations during the same time period and different positions during different time periods are compared and analyzed, the spatiotemporal evolution law of developed coal seam gas drainage in concealed structures is revealed. The research found that concealed structures have a significant impact on parameters such as gas drainage concentration, flow rate, negative pressure and so on, and there are obvious differences in gas drainage effects of different extraction units; The gas drainage concentration in concealed structural areas exhibits a double peak characteristic, while in non-structural areas it exhibits a single peak characteristic. The first peak occurs on the 10 th day of extraction, and the second peak occurs on the 50 th day; The research conclusion provides theoretical basis and practical guidance for the gas governance of developed strong outburst coal seams in deep concealed structures.