LAUSR

Gas extraction to eliminate coal and gas outburst risk is important to ensure safe and efficient coal production for protective layer with coal and gas outburst risk. In this paper, Tonghua coal mine, China, is taken as an example to demonstrate the effects of gas disasters prevention using hydraulic fracturing (HF). The results show that: 1) HF can effectively improve the efficiency of gas extraction. The gas production increased by 62.12% with the borehole number of gas pre-drainage decreased by 45.66%, respectively; 2) efficient gas extraction reduces the occurrence of mine gas safety violations significantly with the gas accidents decreased by 89.3%; 3) the production efficiency of protective layer increased significantly with coal production increased by 49.5%; 4) gas was used for power generation instead of being vented to the atmosphere. This study could be used as a valuable example for other coal deposits being mined under similar geological conditions. [Received: December 4, 2017; Accepted: May 16, 2018]