为提高高原山区两近三软煤层群瓦斯抽采效果，以小窑沟煤矿1805工作面为研究对象，采用分源预测法预测工作面瓦斯涌出量，并针对不同的瓦斯源确定有效的抽采方法，基于卸压瓦斯抽采理论和煤层瓦斯分源治理思想，提出了两近三软煤层群多邻近层采前、采中、采后预抽和卸压抽采相结合的综合瓦斯抽采方法。结果表明：两近三软煤层群上保护层开采时被保护层卸压瓦斯以自然排放为主，采空区瓦斯是保护层工作面瓦斯抽采的重点，采取综合瓦斯抽采措施后，回采过程中保护层工作面回风巷及上隅角瓦斯体积分数由1.7%降到0.5%~0.6%，瓦斯抽采量达到90.05万m3，抽采率由39.5%提高到63.59%，C8煤层开采后C9煤层瓦斯压力由0.95 MPa 降到0.18 MPa，瓦斯含量由12.51 m3/t 降到2.91 m3/t，保护范围内C9煤层突出危险性被消除。%In order to improve gas drainage effect of flat and contiguous seam groups with soft seam,soft roof and soft floor in plateau moun-tain area,taking No.1805 Coal Mining Face in Xiaoyaogou Mine as a study subject,the resources division prediction method was applied to predict the gas emission quantity of coal mining face. And the effective gas drainage method was determined according to different gas re-sources.Based on a pressure released gas drainage theory and seam gas resource division control idea,a comprehensive gas drainage method combined with pre-drainage and pressure released gas drainage was provided before mining,the mining and after mining in multi adjacent seams of flat and contiguous seam groups with soft seam,soft roof and soft floor.The results showed that during mining period of upper protec-tive seam in the flat and contiguous seam groups with soft seam,soft roof and soft floor,the pressure released gas in protected seam would be natural discharging mainly and the goaf gas drainage would be the key in the protective seam coal mining face. After the comprehensive gas drainage measures conducted,during mining process,the gas content in the air retuning gateway and the upper corner of the protective seam coal mining face was reduced from 1.7% to 0.5%~0.6%,the gas drainage volume reached to 900 500 m3 ,an average gas drainage rate was improved from 39.5% to 63.59%,after mining in C8 seam,the gas pressure in C9 seam was reduced from 0.95 MPa to 0.18 MPa,the gas con-tent was reduced from 12.51 m3/t to 2.91 m3/t and the outburst danger of C9 seam in the protection scope was eliminated.
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