五轮山矿区煤层含气性与煤层气理论抽采率

Coal Seam Gas-bearing Properties and Theoretical CBM Recoverable Ratios in Wulunshan Mine Area, Guizhou

基于钻孔煤心解吸数据和煤样等温吸附实验结果,对贵州省五轮山矿区煤层含气性和煤层气理论抽采率进行了研究。结果显示：煤层气解吸率为7.30%-84.48%,平均28.97%,不同煤层解吸率变化较大,3号煤层最高,16号煤层最低;煤层甲烷含量为6.26-32.30m^3/t,平均17.51m^3/t,在平面上表现出＂东高西低、南高北低、深高浅低＂的分布格局,具有向斜控气的特征,不同相邻主煤层之间的含气量梯度呈波动式变化;煤层气理论加权平均抽采率在枯竭压力0.70MPa条件下为27.54%,在0.50MPa条件下为38.49%。结合矿区煤层原生结构完整、煤层埋藏较浅等特点,认为五轮山矿区煤层气具有可观的开发潜力。

Based on borehole coal core desorption data and coal sample isothermal adsorption tested results, studied coal seam gas- bearing properties and theoretical recoverable ratios of CBM. Results demonstrated that the CBM desorption ratios are from 7.30% to 84.48%, average 28.97% and vary from seam to seam, the No.3 coal seam is the highest, No.16 the lowest. Coal seam methane contents are from 6.26-32.30m^3/t, average 17.51m^3/t, horizontally showing ＂high east, low west; high south, low north＂ and ＂high deeper part, low lower part＂ distribution patterns, with synclinal gas-control characteristics. Gas content gradients present fluctuating between neighboring main coal seams. CBM theoretical weighted average recoverable ratios are 27.54% and 38.49% under the depletion pressures of 0.70MPa and 0.50MPa respectively. Considering characteristics of mine area coal seam integrated primary structure and shallower buried depths, reckoned that there is considerable exploitation potential of CBM in the Wulunshan mine area.