摘要:
基于渗流理论,推导了瓦斯抽采过程中,煤层裂隙内负压分布模型,并首次提出了顺层钻孔均压封孔瓦斯抽放技术,该封孔技术采用双负压进行抽放,利用囊袋式封孔器在抽放钻孔内形成主、副抽放腔室,在主、副抽放腔室所产生负压的共同作用下,煤层裂隙内的抽放负压会二次分布,降低了主抽放腔室与外界的压差,同时副抽放腔室所产生的负压会产生屏蔽作用,阻止空气流向主抽放腔室,从而减少抽放过程中漏风,达到提高瓦斯抽放浓度、抽放效率的目的。在中岭煤矿12033运输巷进行了均压封孔瓦斯抽放技术现场试验,传统封孔工艺(聚氨酯封孔)初始5 d平均瓦斯浓度为30.67%,10 d平均瓦斯浓度为21.44%,均压封孔工艺0~50 d平均瓦斯抽放浓度为65.69%。
Abstract:
Based on the seepage theory, the distribution model of the negative pressure in the coal seam cracks during gas extraction is deduced, and the gas drainage technology of equalizing pressure and sealing holes in the borehole along the seam is proposed for the first time. The sealing technology adopts double negative pressure for pumping, and the main and secondary pumping chambers are formed in the drilling hole by using the bag-type sealing device, under the joint action of the negative pressure generated by the main and secondary pumping chambers, the negative pressure in the coal seam cracks will be distributed twice, which reduces the pressure difference between the main pumping chambers and the external environment. At the same time, the negative pressure generated by the auxiliary pumping chamber will have a shielding effect, which preventing air flow to the main pumping chamber, thus reducing air leakage in the pumping process, and achieving the purpose of improving gas drainage concentration and efficiency. The field test of gas drainage technology of equal-pressure sealing hole was carried out in 12033 transportation lane of Zhongling Coal Mine. The average gas concentration of the traditional pore sealing process (polyurethane pore sealing)was 30.67% at the initial 5 d, 21.44% at the 10 d, and 65.69% at the average gas drainage concentration at the 0 to 50 d.
百度学术
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