In view of solving the problems of large top coal loss and low recovery rate in the traditional caving process of horizontal section fully mechanized caving mining, taking the fully mechanized caving face of steeply inclined and extra-thick coal seam in Yimen Coal Mine as the engineering background and the research method of numerical simulation and field measurement was used to study the coal gangue flow characteristics under different coal caving directions and different number of coal caving ports at the bottom plate side, revealing the mechanism of top coal loss and proposing the technology to improve the recovery rate. The results show that the action time of top gangue and the ‘ rotation ‘ of coal gangue flow in the triangle coal area jointly promote the release of triangle coal in the bottom plate, which makes the coal gangue interface steeper and the release rate higher when the coal is released in the lateral direction of the bottom plate; adjusting the number of opening coal mouths when the initial coal caving at the floor side can coordinate the top coal caving speed, gangue down-channeling speed and the closing time of the coal caving mouth. When the first coal caving opens two coal caving mouths, the recovery rate of bottom triangular coal is the highest. Yimen Coal Mine adopted the floor lateral roof side caving and double-mouth caving technology. Compared with the original scheme, the top coal recovery rate of the working face increased by 3%, and the top coal recovery rate of the floor triangle area increased by 7%.

【摘要】：针对解决水平段综放开采传统放顶过程中顶煤损失大、采收率低的问题,以易门煤矿大倾角特厚煤层综放工作面为工程背景和数值模拟与现场测量的研究方法，研究了不同放煤方向和底板侧放煤口数量下的煤矸石流动特性，揭示了顶煤损失机理，提出了技术提高回收率。结果表明，顶矸作用时间和三角煤区煤矸石流的“旋转”共同促进了底板三角煤的释放，使煤矸石界面更陡峭，在底板横向放煤时放出率更高；调整底板侧初放煤时的开煤口数量，可以协调放顶煤速度、矸石下窜速度和放煤口关闭时间。第一次放煤打开两个放煤口时，底三角煤的回收率最高。易门煤矿采用底板侧向顶板侧放法和双口放顶技术。与原方案相比，工作面顶煤回收率提高3%，底三角区顶煤回收率提高7%。调整底板侧初放煤时的开煤口数量，可以协调放顶煤速度、矸石下窜速度和放煤口关闭时间。第一次放煤打开两个放煤口时，底三角煤的回收率最高。易门煤矿采用底板侧向顶板侧放法和双口放顶技术。与原方案相比，工作面顶煤回收率提高3%，底三角区顶煤回收率提高7%。调整底板侧初放煤时的开煤口数量，可以协调放顶煤速度、矸石下窜速度和放煤口关闭时间。第一次放煤打开两个放煤口时，底三角煤的回收率最高。易门煤矿采用底板侧向顶板侧放法和双口放顶技术。与原方案相比，工作面顶煤回收率提高3%，底三角区顶煤回收率提高7%。底三角煤的回收率最高。易门煤矿采用底板侧向顶板侧放法和双口放顶技术。与原方案相比，工作面顶煤回收率提高3%，底三角区顶煤回收率提高7%。底三角煤的回收率最高。易门煤矿采用底板侧向顶板侧放法和双口放顶技术。与原方案相比，工作面顶煤回收率提高3%，底三角区顶煤回收率提高7%。