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

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。

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

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, 1928 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.