在保护层开采及卸压瓦斯抽采技术的实施过程中,由于受煤层倾角、层间距、卸压角和区段煤柱等因素的影响,存在被保护层上的保护范围小于保护层工作面的开采范围、被保护层沿倾向无法连续开采和远距离倾斜煤层群条件同水平的保护层无法完全保护到同水平的被保护层等技术难题。通过研究,采用下列方法可解决上述技术难题:①在走向上对扩界区采用密集钻孔瓦斯抽采的方式,可将走向卸压角由56°~60°提高到90°;②在倾向上采用2个保护层工作面保护1个被保护层工作面;③对于远距离的倾斜下保护层开采,通过下延保护层开采深度,便可实现同水平被保护层的完全保护。在淮南、淮北矿区的应用表明,上述方法可解决保护层开采过程中面临的技术难题,进而实现被保护层工作面与保护层工作面的等长、等宽布置及被保护层在倾向上的连续开采。 During the implementation of the technology of gas extraction and pressure relief in the protective layer, the protection range on the protected layer is less than that of the protective layer due to the influence of coal seam dip angle, layer spacing, pressure relief angle and section coal pillar. Of the mining range, the protected layer along the trend can not be continuous mining and long-distance tilt coal seam group conditions with the same level of protection can not be completely protected to the same level of protection and other technical problems. Through the research, the following technical problems can be solved by adopting the following methods: (1) adopting the method of dense gas drainage by drilling in the expansion zone, the pressure relief angle can be increased from 56 ° to 60 ° to 90 °; (2) On the use of two protective layer face protection of a protected surface; (3) for long-distance tilt of the protective layer mining, by extending the protective layer mining depth, we can achieve the same level of complete protection of the protected layer. The application in the mining areas of Huainan and Huaibei shows that the above method can solve the technical problems in the mining process of the protective layer and realize the equal length and width distribution of the working face of the protected layer and the protective layer, Continuous mining.