关键词: 沁水盆地, 煤层气, 二氧化碳, 注入方式, 提高采收率, 先导试验

Abstract: 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.

Key words: Qinshui Basin, coalbed methane, carbon dioxide, injection mode, enhanced recovery, pilot test