煤层气井水力压裂裂缝导流能力实验评价

Experimental Evaluation on Conductivity of Hydraulic Fracturing in CBM Wells

本文主要围绕煤层气井压裂裂缝导流能力实验评价展开介绍。煤层气井水压裂裂缝导流能力实验表明,与砂岩地层不同,煤层的硬度较小,压裂中支撑剂嵌入情况较严重,导致导流能力降低,加大铺砂浓度能在很大程度上提高煤层裂缝的导流能力。实验中,煤层闭合压力是一个重要的参数,实验对比了在不同闭合压力下,支撑剂颗粒的破碎与嵌入、铺砂浓度、石英砂支撑剂粒径的选择等因素对煤层导流能力的影响。本文所得出的结论对今后煤层气的研究工作及现场施工具有一定的指导意义。

An all-round introduction is given mainly on experimental evaluations on the conductivity of hydraulic fracture .in CBM wells. Compared to sandstone, a coalbed features lower rigidity, leading to more serious proppant embedment in hydraulic fracturing and thus the descent of conductivity, which could be eased byincreasing the consistence of sand filling. Since the closure pressure of coalbed is a key parameter, the experimental comparison of influence on coalbed conductivity is made under different closure pressures between theproppant crashing and embedment, consistence of sand filling and quartz sand proppant diameter. The conclusions drawn in this paper can be used to guide the future study of CBM and field performance.