纤维对压裂液携砂能力的影响

Effects of Fiber on the Proppant Carrying Capacity of Fracturing Fluid

刘玉婷管保山刘萍梁利程兴生邱晓慧

LIU Yu-Ting GUAN Bao-Shan LIU Ping LIANG Li CHEN Xing-Sheng QIU Xiao-Hui

稠化剂浓度的降低会导致压裂液的携砂性能变差，进而影响压裂改造效果。而基液中加入纤维可以在降低压裂液中稠化剂浓度的前提下，保证甚至提高压裂液的携砂能力。静态携砂实验结果表明，随着纤维加量和纤维长度的增加，支撑剂的沉降速度降低。加入质量分数大于0．2％、长度大于8mm的XW-3纤维即可有效改善压裂液的携砂能力，并且纤维对压裂液的耐温耐剪切性能没有影响。在变剪切实验中，随着纤维加量从O增至2．0％，黏度增值由335．9降为107．4mPa·s。加入纤维后，剪切速率的降低对压裂液黏度升高的影响变小。含有纤维的压裂液中，支撑剂的沉降遵循Kyneh定律。在长庆油田关X井的现场应用证实了纤雏改善压裂液携砂能力的可行性。图7表3参11

The decrease of gellant concentration would make the proppant carrying capacity of fracturing fluid become poor.Adding fiber in base fluid could reduce the concentration of gellant under the premise of ensuring the proppant pack stability.The effects of fiber to proppant pack stability were evaluated.Experiment results showed that the settling velocity of proppant decreased with increasing quantity and length of fiber.Fiber XW-3 with content of 0.2% and length of 8 mm could improve the proppant carrying capacity of fracturing fluid.And the addition of fiber was no influence on the temperature and shearing resistance to fracturing fluid.Rheological experiments showed that viscosity value increment reduced from 335.9 to 107.4 mPa · s when the dosage of fiber increased from 0 to 2.0%.Shear rate had smaller effect on the viscosity of fracturing fluid after adding fiber.Fracturing fluid containing fibers followed Kynch proppant sedimentation theory.The application of fracturing fluid in X well of Changqing oilfield on site indicated that fiber could improve the feasibility of fracturing fluid’s carrying capacity.