Application of deep borehole blasting on fully mechanized hard top-coal pre-splitting and gas extraction in the special thick seam

• Published in: International journal of mining science and technology Vol. 25; no. 5; pp. 755 - 760
• Main Authors: Liu, Jian, Liu, Zegong, Xue, Junhua, Gao, Kui, Zhou, Wei
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2015; School of Energy and Safety, Anhui University of Science & Technology, Huainan 232001, China; State Key Laboratory of Deep Coal Mining & Environmental Protection, Huainan 232001, China; Key Laboratory of Safety and High-efficiency Coal Mining, Ministry of Education, Anhui University of Science & Technology, Huainan 232001, China%State Key Laboratory of Deep Coal Mining & Environmental Protection, Huainan 232001, China; Key Laboratory of Safety and High-efficiency Coal Mining, Ministry of Education, Anhui University of Science & Technology, Huainan 232001, China%School of Energy and Safety, Anhui University of Science & Technology, Huainan 232001, China
• Subjects: Deep borehole blasting; Fully mechanized mining; Gas extraction; Hard thick coal seam; Top-coal pre-splitting; 应用; 深孔爆破; 特厚坚硬煤层; 特厚煤层; 瓦斯抽放; 瓦斯预抽; 综放工作面; 预裂; Gas extraction; Deep borehole blasting; Top-coal pre-splitting; Hard thick coal seam; Fully mechanized mining
• ISSN: 2095-2686
• DOI: 10.1016/j.ijmst.2015.07.009

In order to solve the problems of top-coal inadequate destruction and large amounts of gas emission in mining extra thick and hard coal seam,this study investigated the pre-splitting for deep borehole blasting and gas pre-draining technologies on top coal.The mechanism of the technologies was systematically expounded based on hard top-coal cracks development obtained by numerical simulation and theoretical analysis.The results show that explosive blasting in the hard rock results in a large number of cracks and large displacement in the rock mass due to the effect of explosion stress.Meanwhile,the thick top-coal caves,and desorbing gas flows along the cracks improve gas extraction.Finally,the pre-splitting for deep borehole blasting and gas pre-draining technologies was applied in No.3802 working face of Shui Liandong Coal Mine,which increases monthly output in the face to 67.34 kt and the drained gas concentration to 86.2%.The drained gas average concentration from each borehole reaches 40%,and the effect is remarkable.