Zhang Erhui, Zhu Hongqing, Sui Longkun, Gao Jinghong
School of Safety Engineering, North China Institute of Science and Technology, Yanjiao, 065201, Hebei, China.
School of Emergency Management and Safety Engineering, China University of Mining and Technology Beijing, Ding 11, Xueyuan Road, Haidian District, Beijing, 100083, China.
Environ Sci Pollut Res Int. 2025 May;32(24):14550-14572. doi: 10.1007/s11356-025-36501-5. Epub 2025 May 26.
The spatial patterns of gases released for pressure relief are investigated to guide the accurate and efficient extraction of such gases within the mining working face. The work focused on a coal mining face in Inner Mongolia, specifically the 42,205 fully-mechanized mining face. The purpose was to analyze the spatial distribution patterns of pressure-relief gases in both the 42,205 fully-mechanized coal mining working face and the goaf by measuring gas concentration at the mining face and simulating gas migration. A well-organized gas drainage system was implemented based on the distribution characteristics of gases to ensure the accurate and efficient drainage of pressure-relief gases during mining. Certain patterns were observed in gas concentration distribution on the mining face according to the 3D grid method and inverse distance interpolation. Spatially, higher locations on the measurement planes exhibited smaller low gas concentration areas compared to lower locations on the same planes. Both the maximum and minimum gas concentration was located on the goaf's sides on a single measurement plane. Gas concentration behind hydraulic support was significantly higher than that in front of hydraulic support. The horizontal distribution of porosity and permeability demonstrated a concave pattern in the porous media of the goaf. Goaf's sides, especially near the tunnels, had higher porosity and permeability, while the central region had lower values. A noticeable decline existed in both porosity and permeability with the increased distance from floor in the vertical direction. The gas volume fraction was relatively small but with a steep gradient in the shallow part of the goaf. There was a gradual reduction in the gradient of the gas volume fraction as the goaf extended deeper, while its numerical value stabilized after increasing. Gas levels in the upper corner of the 42205 mining face consistently ranged from 0.13 to 0.94% through the monitoring and analysis of continuous on-site gas drainage. Gas concentration ranged from 0.21 to 0.86% in the return airway, and they varied from 0.22 to 0.92% in the mining face. The maximum gas concentration was consistently below 1%, remaining within the safety range and meeting the safety standards outlined in the Coal Mine Safety Regulations. This confirmed the rationality and effectiveness of the arrangement and parameters of the gas drainage system for effective drainage. The results can be applied to engineering and technical personnel and guide the gas control in fully mechanized coal mining faces.
研究了卸压释放气体的空间分布规律，以指导在采煤工作面内准确高效地抽采此类气体。该工作聚焦于内蒙古的一个采煤工作面，具体为42205综采工作面。目的是通过测量采煤工作面的瓦斯浓度并模拟瓦斯运移，分析42205综采工作面和采空区内卸压瓦斯的空间分布规律。基于气体分布特征实施了完善的瓦斯抽采系统，以确保采煤过程中卸压瓦斯的准确高效抽采。根据三维网格法和反距离插值法，在采煤工作面上观察到瓦斯浓度分布呈现一定规律。在空间上，测量平面上较高位置的低瓦斯浓度区域比同一平面上较低位置的小。在单个测量平面上，瓦斯浓度的最大值和最小值均位于采空区两侧。液压支架后方的瓦斯浓度明显高于前方。采空区多孔介质中孔隙率和渗透率的水平分布呈凹形。采空区两侧，尤其是靠近巷道处，孔隙率和渗透率较高，而中心区域较低。在垂直方向上，随着离底板距离的增加，孔隙率和渗透率均显著下降。采空区浅部瓦斯体积分数相对较小但梯度较大。随着采空区深度增加，瓦斯体积分数梯度逐渐减小，其数值在增加后趋于稳定。通过对现场连续瓦斯抽采的监测与分析，42205采煤工作面上隅角瓦斯浓度始终在0.13%至0.94%之间。回风巷瓦斯浓度在0.21%至0.86%之间，采煤工作面瓦斯浓度在0.22%至0.92%之间。瓦斯浓度最大值始终低于1%，处于安全范围内，符合《煤矿安全规程》规定的安全标准。这证实了瓦斯抽采系统布置及参数对于有效抽采的合理性和有效性。研究结果可供工程技术人员参考，指导综采工作面的瓦斯治理。
