Study On Upper Corner Gas Controlling In Working Face Of Spontaneous Combustion Coal Seam In Li Ya Zhuang Mine

With the gradually increasing of mine production and mining depth, coal seam gas emission is increasing at the same time; some part of the working face appears transfinite accumulation in upper corner. So, it is very important to strengthen the prevention and management control of coal mine. We should take effective measures to extract gas in order to providing security for the safety production of coal mine. However, preventing and controlling gas extraction and mined-out area coal of working face spontaneous combustion is a pair of contradiction. Then, it must research and analysis working face in spontaneous combustion of coal seam under specific case, finding the corresponding countermeasures, solving practical problems, making sure the safety of normal mine production.In2-226working face of Li Ya Zhuang coal mine, this paper studies on exploring how to governance corner gas of working face in spontaneous combustion coal, while governing corner gas extraction, taking spontaneous combustion in mined-out area into consideration. Though it is inevitable that gas accumulate in upper corner in U-shaped ventilation, governing corner gas overrun is achievable. It must research the three zones division of mined-out area under the condition of extraction, making the working face gas in upper corner not overrun and mined-out area spontaneous combustion does not occur again. So, we can design the location of extraction holes, quantity, scope of buried tube drainage and drainage negative pressure scientifically, achieving a good effect on gas extraction and reducing the influence of extraction of mined-out area’s combustion three zones.In this paper, the author studies on Li Ya Zhuang mine the2#coal seam, the coal dust with explosion risk; the mine is Class II spontaneous combustion coal seam. The gas emission of2-226working face is much bigger, belonging to high gas mine. Gas from mined-out area is the main sources of upper corner gas emission. So gas control in upper corner research will focus on the research on gas extraction method in mined-out area. Gas accumulation in upper corner has been the difficulty of gas control on the coal working face. By using numerical simulation theory analysis and calculation, field test in this paper, it analyzes the gas emission source and composition of the coal working face, distribution characteristics of mining-induced fractures, causes and laws of gas accumulation in upper corner in detail. Based on the study of the wind of the mining area and the spontaneous combustion three zones of mine-out area, in view of controlling gas in upper corner in U-shaped ventilation mining working face of the spontaneous combustion coal seam, it offers the method of combining the extraction of coal seam drilling in high fields and mined-out area buried tube staggered to extract gas. At the same time, it takes measure to check the negative pressure face, optimize the extraction technology parameters, check the effect of the working face extraction, and check the effect of preventing and controlling coal seam spontaneous combustion. It formulates the judgment basis of spontaneous combustion and its corresponding fire prevention measures. Finally, it concluded the working face extraction parameters for Li Ya Zhuang coal mine in similar conditions. It offers the method of combining the extraction of coal seam drilling in high fields and mined-out area buried tube staggered to extract gas, which suits controlling upper corner gas on the2-226coal working face in Li Ya Zhuang coal mine.Research for coal spontaneous combustion under the condition of high-gas coal mine gob gas extraction is not a lot, especially the law that how to get the mined area leakage, the oxygen concentration distribution and gas distribution in gas extraction process, studying the impact on the gas drainage to spontaneous combustion in mined-out area, and the results about how to reduce the impact of gas extraction on spontaneous combustion is not mature. From2-226working face of Li Ya Zhuang coal mine, this paper studies to explore how to governance corner gas of working face in spontaneous combustion coal, while governing corner gas extraction, taking spontaneous combustion in mined-out area into consideration.This paper formed a set of methods to govern the upper corner by studying the emission characteristics of the working face gas, analyzing the flowing of the wind in the stopping and gas distribution rules. It is proved that combined with high drilling field and staggered tube arrangement to govern the upper corner can overcome disadvantages method of the single high drilling field and the buried tubes. This method could draw on the advantages of each other and cooperates with each other. The industrial test proves this method is feasibility, effectiveness and economy of the technology, through quantitative controlling extraction negative pressure extraction optimization to achieve the goal of governing the upper corner, treating and preventing spontaneous combustion of mined-out area, ensuring the safety of stopping working face.