Reservoir heterogeneity controls of CO_(2)-EOR and storage potentials in residual oil zones:Insights from numerical simulations  

作　　者：Yan-Yong Wang Xiao-Guang Wang Ren-Cheng Dong Wen-Chao Teng Shi-Yuan Zhan Guang-Yong Zeng Cun-Qi Jia 

机构地区：[1]College of Energy,Chengdu University of Technology,Chengdu,610059,Sichuan,China [2]State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu,610059,Sichuan,China [3]Engineering Research Center of Geothermal Resources Development Technology and Equipment,Ministry of Education,Jilin University,Changchun,130026,Jilin,China [4]The University of Texas at Austin,Austin,TX,78712,USA [5]Department of Energy Resources Engineering,Stanford University,Stanford,CA,94305,USA [6]State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu,610059,Sichuan,China

出　　处：《Petroleum Science》2023年第5期2879-2891,共13页石油科学（英文版）

基　　金：the support from Science&Technology Department of Sichuan Province(Grant Nos.2021ZYCD004,2022YFSY0008,2022NSFSC1023);National Natural Science Foundation of China(Grant Nos.42102300,52204033);the Engineering Research Center of Geothermal Resources Development Technology and Equipment,Ministry of Education,Jilin University(Grant No.22003).

摘　　要：Residual oil zones(ROZs)have large potential for CO_(2)enhanced oil recovery(EOR)and geologic storage.During CO_(2)injection,the migration of CO_(2)in ROZs controls the performance of both EOR and storage.However,it has not been clearly visualized and understood that how geological heterogeneity factors control the transport of CO_(2)in ROZs.In this study,the oil recovery performance and geologic storage potential during continuous CO_(2)injection in a representative ROZ are studied based on geostatistical modelling and high-fidelity three-phase flow simulation.We examined the influence of autocorrelation length of permeability,global heterogeneity(DykstraeParsons coefficient),and permeability anisotropy on cumulative oil recovery and CO_(2)retention fraction.Simulation results indicate that,as the permeability autocorrelation length increases,the cumulative oil recovery and CO_(2)storage efficiency decrease.This results from the accelerated migration of CO_(2)along high permeability zones(i.e.,gas channeling).The increase in global heterogeneity and permeability anisotropies can lead to low oil recovery and poor CO_(2)sequestration performance,depending on the degree of CO_(2)channeling.The net utilization ratio of CO_(2)(CO_(2)retained/oil produced)unfavorably increases with both autocorrelation length and Dykstra eParsons coefficient,but decreases with the increase in kv/kh.Such a decrease is attributed to enlarged swept volume induced by gravity override.The study provides important implications for fieldscale CO_(2)EOR and storage applications in ROZs.

关 键 词：Residual oil zones CO_(2)injection Enhanced oil recovery Geologic sequestration 

分 类 号：TE348[石油与天然气工程—油气田开发工程]