底抽巷掘进过老巷瓦斯综合防治技术

Comprehensive Prevention Technology of Gas in Bottom Drainage Roadway Excavation Through Old Roadway

针对老巷残留瓦斯涌入新掘进底抽巷道,致使新巷道瓦斯超限的问题,从主动和被动两方面提出瓦斯综合防治方案,并对抽采主管内瓦斯浓度进行检测分析。结果表明:主管内瓦斯浓度由最初的20%下降至2%,整体下降速率呈“急剧—平稳”的态势。在最初的4 d内,瓦斯浓度明显下降,下降的瓦斯量占总体量的56%,平均每天下降3%;而后10 d内抽采主管瓦斯浓度平稳下降,平均速率为每天下降0.6%,最终达到2%。说明所采取的瓦斯综合治理措施有效,可为类似工程背景下巷道掘进期间瓦斯治理提供参考。

In view of the problem that the residual gas in the old roadway flows into the new excavation bottom pumping roadway,resulting in the gas overrun in the new roadway,the comprehensive prevention and controlplan of gas emission is proposed from both active and passive aspects,and the gas concentration in the extraction main pipe is detected and analyzed.The results show that the gas concentration in the main pipe decreases from the initial 20%to 2%,and the overall decline rate is'sharp-steady'.In the first 4 days,the gas concentration decreased significantly,and the amount of gas decreased accounted for 56%of the to-tal amount,with an average decrease of 3%per day.After that,the gas concentration in the main pipe of ex-traction decreased steadily within 10 days,with an average rate of 0.6%per day,and finally reached 2%.It shows that the comprehensive gas control measures taken are effective,which can provide reference for gas control during roadway excavation under similar engineering background.