松散冲积层下提高煤层群开采上限研究

Study on Upper Limit Increased of Seam Group Mining under Incompact Alluvium

林南仓井田范围内覆盖有140～440m松散冲积层,通过对东一、西一采区主要地质钻孔进行综合统计,研究分析了第四系松散层厚度的分布特征、松散层中含隔水层分布。通过数值模拟确定了近距离煤层群开采后覆岩的导水裂隙带高度。在对导高进行充分预计的基础上,确定了合理的防水煤岩柱的垂高,煤8-1、煤9、煤11和煤12四层煤分别提高开采上限30m、30m、30m和15m,提高开采上限后,增加可采储量为372.6万t。

Within the scope of Linnancang Minefield there was an incompact alluvium with a thickness of 140~440m.With comprehensive statistics conducted on the main geological drillings in the East No.1 Bloock and West No.2 Block,the paper studied and analyzed the thickness distribution features of the Quaternary incompact alluvium and the water insulated strata distribution in the incompact stratum.The numerical simulation was applied to determine the height of the water flow cracking zone in the overburden strata after the mining of the close distance seam group.Base on the full prediction of the water flow height,the rational vertical height of the water prevention coal and rock pillars was determined.The up mining limits of the No.8-1 seam,No.9 seam,No.11 seam and No.12 seam were increased as 30m,30m,30m and 15m individually.After the up mining limits increased,the mineable coal reserves would be increased with 3.726 million t.