摘要
Abstract
The reasonable mining and caving ratio,coal drawing interval and other process parameters is the premise of high yield and high efficiency in fully mechanized top coal caving mining,and plays an important role in improving the mining rate and coal quality.Based on the characteristics of loose medium in soft thick coal seams,No.3 coal seam in Sangbei Coal Mine was taken as the research object,PFC2D particle flow codes was used to establish a model of fully mechanized caving faces,six schemes of different mining heights and coal drawing interval was simulated.Comparative analysis was conducted on the effects of mining height and coal drawing interval on the top coal caving rate and gangue content rate.And a compre-hensive analysis was conducted on the impact of the two factors of mining height and coal caving distance on the comprehen-sive top coal caving rate and comprehensive gangue content.The results indicate that,the top coal release rate shows period-ic changes with the progress of the working face.When Two Mining and One Caving method is used,the fluctuation of the top coal release rate is smaller than that of One Mining and One Caving method,and the gangue content and its fluctuation of the top coal are significantly lower than that of One Mining and One Caving method.The comprehensive top coal release rate of Two Mining and One Caving scheme with a mining height of 2.4 meters is significantly higher than other schemes.There was a positive correlation between comprehensive gangue content of the top coal and mining height when the coal drawing interval is the same.When Two Mining and One Caving method is used,the difference of the comprehensive gangue content of the top coal with a mining height of 2.4 meters and 2.0 meters is not significant.Through engineering practice,the comprehensive caving process of"mining height of 2.4 meters,two mining and one caving,and multi shift interval se-quential caving"for No.3 coal seam of Sangbei Coal Mine was determined.关键词
松软厚煤层/采放比/放煤步距/数值模拟/顶煤放出率/顶煤含矸率Key words
soft and thick coal seam/mining and caving ratio/drawing interval/numerical simulation/top coal caving rate/gangue content of top coal分类
矿业与冶金
