注弱吸附性空气驱替低渗煤层瓦斯的试验研究  

Experimental Research on Gas Displacement of Low Permeability Coal Seam by Injecting Weakly Adsorbent Air

作　　者：董金发 严国超[1] 寇凯博 梁紫栋 丁宏强 相海涛 柳梧泽 DONG Jinfa;YAN Guochao;KOU Kaibo;LIANG Zidong;DING Hongqiang;XIANG Haitao;LIU Wuze(College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China;College of Safety and Emergency Management Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学矿业工程学院,太原030024 [2]太原理工大学安全与应急管理工程学院,太原030024

出　　处：《煤炭技术》2022年第7期105-109,共5页Coal Technology

基　　金：国家自然科学基金资助项目(51974195)。

摘　　要：我国煤层渗透性普遍较低,这一特点决定了我国煤层瓦斯促排、促抽难度大。注CO_(2)驱替煤层瓦斯是近年来一种新兴的高效促排、促抽瓦斯增产技术,其理论和应用技术已日趋成熟,考虑到煤层压注CO_(2)时,现场制取难度大,供气量难以满足现场需要。为此,从井下气源获取的角度考虑,提出了注弱吸附性空气驱替煤层瓦斯技术。通过分析注空气对煤层瓦斯置换、气流的稀释扩散以及煤层膨胀增透的多重作用,选择在山西常村煤矿3#煤层掘进工作面进行注空气强化瓦斯促排的现场试验。根据瓦斯浓度、流量等相关参数进行对比分析。现场实践表明:注空气3 h后,钻孔瓦斯浓度相比于注气前,下降幅度为60%~80%,钻孔纯瓦斯流量为注气前的1.33~2.15倍,井下煤层注空气促排瓦斯效果显著,可为高瓦斯低渗透性煤层快速促排瓦斯提供一种参考。The permeability of coal seams in China is generally low,which determines the difficulty of accelerating gas emission and drainage in coal seams in China.CO_(2) injection displacement of coal seam gas is an emerging and efficient technology to promote gas emission and gas drainage in recent years,and its theory and application technology have become increasingly mature,considering that when CO_(2) is injected into coal seam,it is difficult to make it on site,and the gas supply can not to meet the needs of the site.For this reason,from the perspective of underground gas source acquisition,the technology of injecting weak adsorptive air to drive coal seam gas is proposed.By analyzing the multiple effects of air injection on coal seam gas displacement,dilution and diffusion of gas injection flow and coal seam permeability improvement,the field test of air injection to enhance gas emission was carried out in No.3 coal seam heading face of Changcun coal mine in Shanxi province.Comparative analysis is carried out according to relevant parameters such as methane concentration and flow rate.The field practice shows that after air injection 3 hours,the gas concentration in the borehole is reduced by 60% to 80% compared to that before gas injection,and the pure gas flow increased by 1.33-2.15 times,the effect of underground coal seam air injection is remarkable,which can provide a reference for rapid promoting gas emission in high gas and low permeability coal seams.

关 键 词：低渗透性煤层 掘进工作面 注气 驱替瓦斯 

分 类 号：TD712[矿业工程—矿井通风与安全]