The mechanism of hydraulic fracturing assisted oil displacement to enhance oil recovery in low and medium permeability reservoirs

作     者：LIU Yikun WANG Fengjiao WANG Yumei LI Binhui ZHANG Dong YANG Guang ZHI Jiqiang SUN Shuo WANG Xu DENG Qingjun XU He LIU Yikun;WANG Fengjiao;WANG Yumei;LI Binhui;ZHANG Dong;YANG Guang;ZHI Jiqiang;SUN Shuo;WANG Xu;DENG Qingjun;XU He

作者机构：Laboratory of Enhanced Oil Recovery of Education MinistryNortheast Petroleum UniversityDaqing 163318China Postdoctoral Res CtrDaqing Oilfield Company LimitedDaqing 163453China Downhole Services Company of Daqing Oilfield Company LimitedDaqing 163453China Exploration and Development Research Institute of Daqing Oilfield Company LimitedDaqing 163712China The NO.1 Production Plant of Daqing Oilfield Company LimitedDaqing 163712China 

出 版 物：《Petroleum Exploration and Development》 (石油勘探与开发（英文版）)

年 卷 期：2022年第49卷第4期

页      面：864-873页

核心收录：

学科分类：0820[工学-石油与天然气工程] 08[工学] 0708[理学-地球物理学] 082002[工学-油气田开发工程] 

基　　金：Supported by the National Natural Science Foundation of China(52074087,51804076) Postdoctoral Natural Science Foundation of China(2021M690528). 

主　　题：hydraulic fracturing chemical flooding formation energy enhancement remaining oil distribution oil displacement mechanism enhancing oil recovery 

摘      要：Aiming at the technology of hydraulic fracturing assisted oil displacement which combines hydraulic fracturing,seepage and oil displacement,an experimental system of energy storage and flowback in fracturing assisted oil displacement process has been developed and used to simulate the mechanism of percolation,energy storage,oil displacement and flowback of chemical agents in the whole process.The research shows that in hydraulic fracturing assisted oil displacement,the chemical agent could be directly pushed to the deeper area of the low and medium permeability reservoirs,avoiding the viscosity loss and adhesion retention of chemical agents near the pay zone;in addition,this technology could effectively enlarge the swept volume,improve the oil displacement efficiency,replenish formation energy,gather and exploit the scattered residual oil.For the reservoir with higher permeability,this measure takes effect fast,so to lower cost,and the high pressure hydraulic fracturing assisted oil displacement could be adopted directly.For the reservoir with lower permeability which is difficult to absorb water,hydraulic fracturing assisted oil displacement with surfactant should be adopted to reduce flow resistance of the reservoir and improve the water absorption capacity and development effect of the reservoir.The degree of formation energy deficit was the main factor affecting the effective swept range of chemical agents.Moreover,the larger the formation energy deficit was,the further the seepage distance of chemical agents was,accordingly,the larger the effective swept volume was,and the greater the increase of oil recovery was.Formation energy enhancement was the most important contribution to enhanced oil recovery(EOR),which was the key to EOR by the technology of hydraulic fracturing assisted oil displacement.