沁水盆地南部注二氧化碳提高煤层气采收率微型先导性试验研究

Micro-pilot test for enhanced coalbed methane recovery by injecting carbon dioxide in south part of Qinshui Basin

在沁水盆地南部TL-003井进行了单井注入CO2提高煤层气采收率试验。采用间歇式注入方式,共向3号煤层注入192.8t液态CO2。生产和储层模拟评价结果表明,大部分CO2被煤层吸附,能显著提高单井产量和采收率。多井试验模拟显示,在沁南无烟煤煤层中注入CO2,能显著地提高煤层气采收率,同时实现了埋藏CO2的目标。

A new kind of technology for using CO2 injection was proposed to enhance coalbed methane （CBM） recovery and store CO2 in the non-mineable deep coal seams. The micro-pilot test for CO2 injection was performed in TL-003 Well of the southern Qinshui Basin. In the micro-pilot test, 192.8 tons of liquefied CO2 were intermittently injected into No. 3 coal seam. A set of high-quality data were obtained, including the injection rates, surface and bottom-hole pressures and temperatures during injecting CO2 period, the bottom-hole pressures and temperatures during shut-in period, and the bottom-hole pressures and temperatures, gas and water production rates, and gas composition during production period. The history match of the dataset from the micro-pilot test was successful with the CMG simulator. The multi-well simulation and numerical prediction indicated that CO2 was almost adsorbed into No. 3 coal seam, and the coalbed methane recovery increased markedly, while CO2 could be stored in No. 3 coal seam for a long term in south part of Qinshui Basin.