超临界CO_(2)压裂缝内支撑剂运移规律  

Proppant Migration in Fracture Fractured with Supercritical CO_(2) Fracturing Fluid

作　　者：郭兴 孙晓 穆景福 乔红军 罗攀 李恒 GUO Xing;SUN Xiao;MU Jingfu;QIAO Hongjun;LUO Pan;LI Heng(Research Institute of Shaanxi Yanchang Petroleum(Group)Company Limited,Xi’an,Shaanxi 710065;Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery,Xi’an,Shaanxi 710065;Peking University,College of Engineering,Beijing 100871)

机构地区：[1]陕西延长石油(集团)有限责任公司研究院,西安710065 [2]陕西省二氧化碳封存与提高采收率重点实验室,西安710065 [3]北京大学工程学院,北京100871

出　　处：《钻井液与完井液》2022年第5期629-637,共9页Drilling Fluid & Completion Fluid

基　　金：陕西省创新能力支撑计划项目“CO_(2)压裂井筒温压及地层波及规律研究”(2019KJXX-023);国家科技重大专项“延安地区陆相页岩气勘探开发关键技术”课题四“非均质陆相页岩气储层压裂改造配套工艺技术”(2017ZX05039-004)。

摘　　要：为了优化超临界CO_(2)压裂工艺技术和施工参数,考虑超临界CO_(2)压裂液中支撑剂颗粒之间相互作用,采用欧拉-拉格朗日方法中的多相质点网格方法,建立超临界CO_(2)压裂缝内支撑剂运移数学模型,通过室内水力压裂支撑剂运移物模实验验证模型准确性,进行超临界CO_(2)压裂缝内支撑剂运移规律计算和分析。研究表明:未增黏CO_(2)由于黏度低,携砂效果极差,优化其他参数对携砂效果影响不大;CO_(2)黏度增加到2.5 mPa·s即可有效提高携砂效果,采用超轻支撑剂与细尺寸颗粒组合,携砂效果与增黏到10 mPa·s效果相差不大;优化支撑剂密度比尺寸对携砂效果提高更为明显;增大排量可以提高携砂效果,但排量继续增大,其携砂效果变化较小;流体滤失对CO_(2)携砂效果影响变化不大。该研究为解决CO_(2)携砂性能差的问题提供了技术支撑,对超临界CO_(2)压裂设计优化及现场施工具有重要指导意义。In order to optimize the supercritical CO_(2) fracturing technology and construction parameters,considering the interaction between proppant particles in supercritical CO_(2) Fracturing Fluid,the multiphase particle grid method in Euler Lagrange method is used to establish the mathematical model of CO_(2) fracturing proppant migration.The accuracy of the model is verified by indoor hydraulic fracturing proppant migration model experiment,and the supercritical CO_(2) fracturing proppant migration law is calculated and analyzed.Research shows:Due to the low viscosity of non tackifying CO_(2),the sand carrying effect is very poor,and the optimization of other parameters has little effect on the sand carrying effect;When the viscosity of CO_(2) increases to 2.5 mPa·s,the sand carrying effect can be effectively improved.The combination of ultra-light proppant and fine particles has little difference between the sand carrying effect and the viscosity increasing to 10 mPa·s;Optimizing the density ratio of proppant to size can improve the sand carrying effect more obviously;Increasing the displacement can improve the sand carrying effect,but if the displacement continues to increase,the sand carrying effect changes little;Fluid filtration has little effect on CO_(2) sand-carrying effect.This study provides technical support for solving the problem of poor sand carrying performance of CO_(2),and has important guiding significance for supercritical CO_(2) fracturing design optimization and field construction.

关 键 词：超临界CO_(2) 压裂 裂缝 支撑剂 运移 

分 类 号：TE357[石油与天然气工程—油气田开发工程]