高含水油藏CO_(2)人工气顶驱油-封存适宜条件研究  

Suitable conditions for CO_(2) artificial gas cap flooding-sequestration in high water cut reservoir

作　　者：王军[1] 邱伟生 WANG Jun;QIU Weisheng(Research Institute of Exploration and Development,Sinopec East China Oil&Gas Company,Nanjing,Jiangsu 210019,China)

机构地区：[1]中国石化华东油气分公司勘探开发研究院,江苏南京210019

出　　处：《油气藏评价与开发》2024年第1期48-54,63,共8页Petroleum Reservoir Evaluation and Development

基　　金：江苏省项目“苏北地区二十万吨级CCUS重大科技示范工程”(BE2022603)。

摘　　要：针对水驱油藏开发进入高含水阶段后,剩余油常富集在构造高部位或厚油层顶部,井网控制不到的问题,利用油藏自身特点注CO_(2)形成气顶驱,可有效改善开发效果并实现CO_(2)封存,但什么样的油藏适宜开展气顶驱尚待研究。通过剖析典型高含水油藏CO_(2)气顶驱见效特征,分析气顶驱油过程中油气界面移动规律,结合数值模拟、物理模拟,以提高采收率幅度、换油率、到达极限气油比时间、存气率等为主要评价标准,研究地层倾角、原油密度、黏度、油藏封闭性、渗透率、水动力强弱等相关参数对CO_(2)气顶驱油-封存效果的影响。按照到达极限气油比时提高采收率的幅度大小,评价各参数对驱油--封存效果的影响程度,确定高含水期油藏的CO_(2)气顶驱油-封存筛选条件主要受油藏封闭性、地层倾角、原油黏度、油层渗透率及厚度影响,为拓展CO_(2)驱应用范围提供了依据。In the development of water-flooded oil fields entering the high water-cut stage,the remaining oil often accumulates at the top of structural high positions or thick oil layers,areas not effectively covered by the existing well network.Utilizing the intrinsic characteristics of the reservoir to inject CO_(2) and form a gas cap drive can effectively improve development outcomes and achieve CO_(2) sequestration.However,the suitability of specific reservoirs for gas cap drive development requires further study.This study delves into the effectiveness of CO_(2) gas cap drive in high water-cut reservoirs by examining the movement of the oil-gas interface during the gas cap drive process,using both numerical and physical simulations.Key evaluation metrics include enhanced oil recovery rate,oil displacement efficiency,time to reach the critical gas-oil ratio,and gas retention rate.The research assesses how various reservoir characteristics,such as formation dip angle,crude oil density,viscosity,reservoir confinement,permeability,and the strength of water drive,influence the efficiency of CO_(2) gas cap drive for both oil displacement and sequestration.Focusing on these main evaluation criteria,the study identifies that the suitability of CO_(2) gas cap drive in reservoirs during the high water-cut phase is significantly influenced by factors such as reservoir confinement,formation dip angle,crude oil viscosity,permeability,and reservoir thickness.These findings aim to provide a foundation for broadening the application of CO_(2) flooding techniques.crude oil viscosity,reservoir permeability,and thickness,to provide a basis for expanding the application range of CO_(2) flooding.

关 键 词：高含水 CO_(2)人工气顶 敏感性因素 地层倾角 水动力强弱 存气率 

分 类 号：TE32[石油与天然气工程—油气田开发工程]