纤维压裂液携砂性能实验评价

Exprimental evaluation of the proppant carrying capacity of fiber fracturing fluid

为了研究纤维对纤维加砂压裂的影响,设计了大型可视裂缝模拟系统及相应的实验方案,通过室内实验,研究了纤维加入方式、纤维浓度、温度等对纤维携砂能力的影响。实验结果表明:先加入纤维,再加入交联剂,最后加入支撑剂配置的压裂液携砂能力最好;在一定温度范围内,纤维质量浓度越高,纤维与支撑剂颗粒间摩擦系数越大,形成的网状结构越稳定,纤维的悬砂性越好,但温度大于80℃时,纤维携砂能力变差;增大纤维质量浓度,砂堤形态变平缓,堤峰向裂缝深部推移,支撑剂在裂缝深部的沉降量增加,有利于增加裂缝的有效长度。

A large-scale visual fracture simulation system and experimental schedule have been designed with consideration of fiber adding method, fiber concentration, and temperature to study the effect of fiber on fiber fracturing. Experimental results show that fracturing fluid carrying capacity was the best through adding fiber, then crosslinking agent, and finally proppant. In a certain temperature range, the higher the fiber concentration, the more stable the network, and the carrying capacity was better, but it became worse when the temperature exceeded 80℃. With increasing of fiber concentration, the sand bank became flat, and the amount of proppant in deep fracture increased, leading to increase of the effective length of the fracture. This study may provide reference for the design of fiber sand fracturing.