摘要
油藏CO_2驱过程中,CO_2与地层水和岩石矿物发生化学反应,影响地层物性和CO_2的埋存形式。基于吉林油田某高温油藏的地层及流体性质,建立考虑地层水蒸发、水中CO_2溶解扩散、CO_2-地层水-岩石地化反应和孔渗关系的CO_2驱及埋存综合模拟模型,分析不同阶段的地化反应特征和CO_2埋存形式,研究CO_2注入方式对提高采收率和埋存效率的影响。结果表明:在CO_2驱油阶段,地化反应对储层孔隙度和渗透率产生一定影响,但对采收率的影响较小,CO_2主要以构造形式埋存于油藏内;在后续埋存阶段,气态CO_2通过地化反应不断转化为矿物形式,造成地层压力下降;水气交替注入方式可提高原油最终采收率和CO_2一次埋存效率,应为首选注入方式;对于其CO_2埋存量的不足,可在CO_2驱后注入一定的CO_2进行补充,同时起到维持地层压力的作用。
Geochemical reactions among CO2-fromation water-rocks can occur and affect the physical properties of the reser-voir and the CO2trapping mechanisms during CO2EOR process.In this paper,based on the properties of the reservoir andfluids in a typical high-temperature oil reservoir in Jilin Oilfield,a comprehensive model was established to simulate the CO2EOR and the subsequent storage,processes,in which formation water evaporation,dissolution and diffusion of CO2in water,CO2-water-rock geochemical reactions and variations of porosity and permeability were considered.The geochemical reactionsand various CO2trapping forms in different stages were analyzed using the model,and the influences of different CO2injec-tion methods on EOR and CO2storage were evaluated.The results show that,though the geochemical reactions can changereservoir porosity and permeability,their effect is not significant and most of the injected CO2can be trapped as supercriticalgas during CO2EOR process.During CO2storage,gaseous CO2can be continuously converted into mineral forms due to geo-chemical reactions,which results in a reduction of reservoir pressure.A WAG(water alternative gas injection)method can be applied to enhance oil recovery and increase CO2storage efficiency.Further injection of CO2after CO2EOR process canincrease the CO2storage capacity,and simultaneously maintain the reservoir pressure.
作者
崔国栋
张亮
任韶然
章杨
CUI Guodong;ZHANG Liang;REN Shaoran;ZHANG Yang(School of Petroleum Engineering in China University of Petroleum, Qingdao 266580, China;Oil Production Technology Institute, Dagang Oilfield Company, Tianjin 300280, China)
出处
《中国石油大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2017年第6期123-131,共9页
Journal of China University of Petroleum(Edition of Natural Science)
基金
国家自然科学基金项目(51674282)
中央高校基本科研业务费专项(17CX06006)
中国石油大学(华东)研究生创新工程项目(YCX2017022)
"十三五"国家油气重大专项(2016ZX05056004-003)
关键词
高温油藏
CO2驱
CO2埋存
地化反应
埋存效率
high-temperature oil reservoir
CO2 displacement
CO2 storage
geochemical reactions
storage efficiency
