Coalbed methane (CBM) is an efficient energy source that mainly contains CH₄ and CO₂. Multibranch horizontal wells (MBHWs) are widely used in CBM extraction. In the study, CH₄ and CO₂ were employed to perform CBM extraction experiments by MBHWs. Based on the experiments, a phenomenon occurs wherein gas from the high‐pressure production layer enters the low‐pressure production layer during the initial stage. Reservoir pressure, temperature, permeability, and instantaneous flow rate exhibit similar evolution laws. Specifically, they initially increase sharply, then declining rapidly, and finally level off in the production layer with the minimum initial pressure. Increase in the adsorption capacity lowers the increase in reservoir pressure, although the phenomenon persists longer from appearance to disappearance. The moment of permeability recovery is related to the adsorption capacity, and the moment of permeability recovery under CO₂ conditions occurs after that under CH₄ conditions. The instantaneous flow rate curve is divided into three categories, namely steep flow rate increase curve, flow rate inhibition curve, and backflow curve. The results are useful for CBM extraction of multiple coal seams.

中文翻译：

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多分支水平井抽采煤层气中不同吸附气体对储层参数及产量的影响

煤层气（CBM）是一种高效能源，主要包含CH ₄和CO ₂。多分支水平井（MBHW）被广泛用于煤层气的开采。在研究中，CH ₄和CO ₂用MBHWs进行煤层气提取实验。根据实验，出现了一种现象，即在初始阶段，高压生产层的气体进入低压生产层。储层压力，温度，渗透率和瞬时流量表现出相似的演化规律。具体来说，它们最初急剧增加，然后迅速下降，最后以最小的初始压力在生产层中趋于平稳。吸附能力的增加降低了储层压力的增加，尽管这种现象从出现到消失一直持续较长时间。渗透率恢复的时刻与吸附能力有关，CO ₂条件下的渗透率恢复的时刻发生在CH _4下。情况。瞬时流量曲线分为三类，即陡峭的流量增加曲线，流量抑制曲线和回流曲线。该结果对于多个煤层的煤层气开采是有用的。