基于CBM-SIM的梨树煤矿瓦斯地面抽采数值模拟

Numerical simulation of surface gas extraction based on CBM-SIM in Lishu coal mine

  • 摘要: 针对煤矿准备区、规划区瓦斯抽采的时空接续要求不同,基于黑龙江鸡西梨树煤矿瓦斯地面抽采试验井,利用CBM-SIM数值模拟软件对已有试验井的生产数据进行历史拟合,实现了储层的精确表征。通过CBM-SIM软件模拟井组抽采5 a、10 a、15 a的产气情况,以及抽采5 a瓦斯含量动态变化情况,最终确定了不同区域的最佳井间距。模拟结果表明,准备区和规划区最优井间距分别为200 m×250 m和300 m×300 m。准备区布井7口,规划区布井64口;准备区抽采5 a采收率为32.30%~38.20%,瓦斯含量可降至8 m3/t以下,满足矿井安全生产。规划区抽采5 a,采收率为30.00%~39.05%;抽采10 a,采收率为41.78%~52.06%,除规划区Ⅲ、Ⅴ以外,其他区域瓦斯含量均可降低至8 m3/t以下;抽采15 a,采收率为48.20%~62.04%,除规划区Ⅴ以外,其他区域瓦斯含量均可降低至8 m3/t以下。研究成果可为梨树煤矿及其东北其他矿区深部薄煤层区的煤与瓦斯协同共采提供借鉴。

     

    Abstract: To meet different requirements of time and space for gas extraction in preparation and planning area, based on the coalbed methane well test in Lishu coal mine, coalbed methane simulation software CBM-SIM was used to do history match and achieve precise reservoir parameters. For vertical wells in rectangular pattern, CBM-SIM was applied to predict gas rate for 5 years, 10 years and 15 years for 7 diffrent kinds of well spacing, and the dynamic change of gas content for 5 years, eventually determine the best well spacing in different area. Based on the above conclusion, considering all factors, wells were drilled in Lishu coal mine, and gas extraction was predicted by simulation. The results of the study show that the optimal well spacing for preparation areas is 200m×250m and 300 m×300 m for planning areas. 7 wells were placed in preparation areas and 64 wells in planning areas; the recovery ratio for 5 years in the preparation area will be 32.30%~38.20%, the gas content can be reduced to below 8 m3/t, meeting the requirements for safe production in the mine; the recovery ratio in the planning area will be 30.00%~39.05% for 5 years, 41.78%~52.06% for 10 years. Except the planning areas and Ⅲ Ⅴ, the gas content can be decreased to below 8 m3/t in other areas, for extraction for 15 years, the recovery ratio will be 48.20%~62.04%. The research results provide reference for the coal and gas co-extraction in Lishu coal mine and other mining areas of the deep thin coal seam in Northeast China.

     

/

返回文章
返回