煤矿井下长钻孔煤层瓦斯含量精准测试技术及装置

Accurate test technology and device for coal seam gas content in long boreholes in underground coal mines

针对煤矿井下大范围超前探测煤层瓦斯含量的实际需求,提出了煤矿井下煤层瓦斯含量测试密闭取心方法,设计并试制了适合于煤矿井下长钻孔煤层瓦斯含量精准测试的“三筒单动、球阀密闭”的密闭取心装置,装置外径89mm,采取煤心直径可达38mm;密闭能力达到11MPa以上,满足于煤矿井下煤层瓦斯含量测定密闭取样要求。井下工程试验结果显示,该装置的煤层密闭取心取样深度达到360.5m,5组密闭取心法测得的煤层瓦斯含量为常规取心法测值的1.26~3.07倍,平均2.25倍。该技术将为我国煤矿井下煤层瓦斯含量大范围精准探测、区域瓦斯治理及效果检测提供一种有效的技术手段。

In order to get actual gas content of underground coal mine during large-scale advanced detection,the sealed coring method for gas content was proposed.The sealed coring device of “three-cylinders,single motion and ball valve sealing” suitable for accurate test of gas content of long boreholes in underground coal mines was designed and trial-produced,the outer diameter of the device is 89 mm,and the diameter of the coal core can reach 38 mm,the pressure holding capacity of the sealed coring device is above 11 MPa,which satisfies the requirement of sealing sampling for the determination of coal seam gas content in underground coal mines.By using the sealed coring device to carry out the test of gas content determination of underground coal coring in typical coal mines in China,the depth of coal coring in coal coring reached 360.5 m.The coal seam gas content measured by 5 groups of sealed coring method was 1.26~3.06 times higher than that of conventional coring method,with an average of 2.25 times.This technology will provide an effective technical means for test of the effect of extensive accurate detection of gas content and regional gas control in underground coal mines in China.