瓦斯抽采钻孔解堵修复装备的研制与应用

Development and application of gas drainage borehole plug removal and repair equipment

煤层瓦斯抽采是解决煤矿瓦斯灾害的主要技术措施,而失稳坍塌和煤渣积聚造成的钻孔堵塞失效严重影响瓦斯抽采效果。为了解决上述问题,利用高压水射流在破孔透孔和疏通排渣方面的技术优势,研制了轻型气动水力化解堵修复装备,确定了该系统装备的水力参数,包括系统阻力损失、水力破煤岩参数和钻孔修复喷头结构参数,实现了对钻孔堵塞段的疏通解堵,形成了经济、高效的瓦斯抽采钻孔修复技术工艺。在石壕煤矿南五区3#瓦斯巷应用结果表明,试验穿层钻孔23个,修复后效果显著的钻孔达91.3%,修复完成后45 d内单孔平均抽采瓦斯浓度和纯流量由36%和0.0035 m^(3)/min提升至60%和0.0082 m^(3)/min,分别提高了67%和134%,解堵修复效果较好,有效提高了瓦斯抽采钻孔的利用率和抽采效率。

Coal seam gas drainage is the main technical measure to solve coal mine gas disasters,and the failure of drilling blockage caused by instability collapse and coal slag accumulation seriously affects the gas drainage effect.In order to solve the above problems,based on the technical advantages of high pressure water jet in the aspects of hole breaking,hole penetrating and slag discharging,a light pneumatic hydraulic plug removal and repair equipment is developed.The hydraulic parameters of the system equipment are determined,including the system resistance loss,hydraulic coal rock breaking parameters and the structural parameters of the rotating nozzle.It realizes the dredging and unplugging effect on the blocked section of the drilling,forming an economical and efficient drilling repair technology for gas extraction.The application results in No.3 gas lane in the south 5th district of Shihao Coal Mine show that,23 test drillings are drilled through the strata,and 91.3%of the drillings with significant effect after repair are completed.Within 45 d after the completion of repair,the average gas density and pure flow rate of a single hole are increased from 36%and 0.0035 m^(3)/min to 60%and 0.0082 m^(3)/min,which are increased by 67%and 134%,respectively.The effect of plug removal and repair is good,which effectively improves the utilization rate and drainage efficiency of the extraction drilling.