非规则支撑剂团簇对裂缝导流能力的影响实验评价

Experimental evaluation of the influence of irregular proppant cluster on the fracture conductivity

明确脉冲压裂裂缝导流的控制因素与受控机制对优化压裂设计和提高压裂改造效果具有重要意义。针对脉冲压裂导流能力的评价研究忽略了支撑剂团簇的非规则形态与分布特征的影响,导致对脉冲压裂裂缝导流能力认识存在较大不足。以中国东海气田为目标,开展了脉冲压裂裂缝导流能力室内实验评价,深入研究了支撑剂团形状特征和排列方式对裂缝导流能力的影响规律。实验结果表明,小尺寸椭圆形支撑剂团分散铺置方式在高闭合压力下的团簇稳定性更好,团簇间的空隙率更大,流体流动路径连通性更优,有利于保持更高的裂缝导流能力。取得的研究认识对揭示脉冲压裂裂缝导流能力影响规律,完善脉冲压裂优化设计具有重要理论价值和现实意义。

It is of great signifance to define the controlling factors and the controlled mechanisms of fracture conductirity of pulse fracturing for optimizing the fracturing design and improving the fracturing reconstruction.In the light of the ignored influences by the evaluating study on the pulse fracturing conductivity in the irregular shape and distribution characteristics of the proppant clusters,there is a great lack of understanding of the pulse-fracturing fracture conductivity.Taking China Donghai gas field as the target,the indoor experimental evaluation of the fracture conductivity for the pulse fracturing was carried out and the influencing laws of the shape characteristics and arrangement of the proppant cluster on the fracture conductivity were deeply researched.The experimental results show that the dispersed placement of the small-sized elliptical proppant cluster can maintain better cluster stability under the high closing pressure and moreover can have larger porosity,thus the connectivity of the liquid flow path can be more optimized,and all these improvements are prone to maintain more higher fracture conductivity.The research understandings possess the important theoretical values and practical significances for revealing the influencing laws of the pulse-fracturing fracture conductivity and perfecting the pulse-fracturing optimization design.