基于溶胀–熟化机理的疏水缔合聚合物速溶压裂液技术

An Instantly Dissolving Fracturing Fluid Technology Using Hydrophobic Associating Polymers Based on Swelling-Curing Mechanisms

吕振虎 邬国栋 郑苗 杨建强 向英杰

LYU Zhenhu WU Guodong ZHENG Miao YANG Jianqiang XIANG Yingjie

中国石油新疆油田分公司工程技术研究院，新疆克拉玛依 834000 中国石油新疆油田分公司勘探开发研究院，新疆乌鲁木齐 830001

Engineering Research Institute, PetroChina Xinjiang Oilfield Company, Karamay, Xinjiang, 834000, China Research Institute of Exploration and Development, PetroChina Xinjiang Oilfield Company, Urumqi, Xinjiang, 830001, China

针对疏水缔合聚合物配制压裂液时分散性能差、溶胀时间长和不适合现场连续混配的问题，综合机械与化学方法，研究了疏水缔合聚合物速溶压裂液技术。通过优化助溶剂加量，减小配液用水的溶度参数，利用负熵因素加快聚合物溶胀速率；同时，设计了同轴双向搅拌装置，提高了固液混合物紊流程度，缩短了聚合物熟化时间。试验结果表明：溶度参数与溶胀胶团直径是影响聚合物溶胀与熟化的关键因素；4%助溶剂可使疏水缔合聚合物的溶胀率在4 min内达到92%；搅拌速率对疏水缔合聚合物熟化时间的影响较小，搅拌方式是影响疏水缔合聚合物熟化速度的主要因素，同轴双向搅拌6 min时的溶胀率达到86%；形成的疏水缔合聚合物速溶压裂液在90 ℃条件下的抗剪切性能大于180 mPa·s，满足现场施工要求。疏水缔合聚合物速溶压裂液技术实现了聚合物压裂液连续混配，降低了聚合物压裂液残液、余液对环境的影响，为大规模体积压裂工厂化作业提供了技术支撑。

Due to hydrophobic associating polymers fracturing fluid have problems, such as poor dispersing performance, a long swelling time and which was unsuitable for continuous mixing at the wellsite. Thus, an instantly dissolving fracturing fluid technology using hydrophobic associating polymer has been developed by comprehensively combining mechanical and chemical methods. The solubility parameter for fluid preparing was reduced through the development of a cosolvent, and the swelling time of polymer was accelerated by utilizing the negative entropy factor. The coaxial bi-directional stirring device was designed to improve the turbulent flow of solid-liquid mixture and to shorten the curing time of the polymer. Experiments showed that the solubility parameter and the swelling micelle diameter were the key factors affecting the swelling and curing of polymer. The swelling ratio of hydrophobic associating polymer reached 92% in 4 min by adding 4% cosolvent. We found that the stirring rate has little effect on the curing time of such polymer, and further, the stirring method is the main factor affecting the curing speed of polymer. The swelling ratio of the coaxial bi-directional stirring method reached 86% in 6 min, and the developed instant dissolving hydrophobic associating polymer fracturing fluid system have the shear resistance of greater than 180 mPa·s at 90 °C, which satisfies the field requirements. The new fracturing fluid technology could achieve the continuous mixing of polymer fracturing fluid, and reduce the influence of residual fluids on the environment, which provided technical support for the implementation of large-scale volumetric fracturing in factory mode.

中国石油天然气股份有限公司油气开发重大科技项目“新疆油田和吐哈油田勘探开发关键技术研究与应用”课题14“降本提效试油及采油关键技术研究与应用”（编号：2017E-0414）资助

https://doi.org/10.11911/syztjs.2019018