Surfactant enhanced oil recovery(EOR)includes surfactant flooding and surfactant stimulation.The main functions of surfactants are to reduce interfacial tension and wettability alteration.This paper is to review the E...Surfactant enhanced oil recovery(EOR)includes surfactant flooding and surfactant stimulation.The main functions of surfactants are to reduce interfacial tension and wettability alteration.This paper is to review the EOR technology related to surfactant injection.The reviewed topics include the following:Surfactant EOR mechanismsFactors affecting interfacial tension Trapping numberScreening criteriaLaboratory work Numerical simulation work Summary of pilot and large-scale applications Surfactants used Salinity gradientSurfactant EOR in carbonate reservoirs Surfactant EOR in shale reservoirs.展开更多
Coreflood,interfacial tension(IFT),contact angle,and phase behavior measurements were performed to investigate the viability of a hybrid of low-salinity water,surfactant,and CO_(2) flood enhanced oil recovery(EOR)proc...Coreflood,interfacial tension(IFT),contact angle,and phase behavior measurements were performed to investigate the viability of a hybrid of low-salinity water,surfactant,and CO_(2) flood enhanced oil recovery(EOR)process.Low-permeability carbonate reservoir cores were aged for eight weeks at reservoir temperature and pressure.Coreflood and contact angle between oil droplets and core surface measurements were performed.Additional contact angle measurements on sandstone and shale cores were also performed.The coreflood sequences were seawater flood,followed by low-salinity water flood,followed by surfactant floods until residual oil saturations to each flooding sequences and finally CO_(2) injection.Coreflood in low-permeability carbonate cores show that the hybrid EOR process produces incremental oil up to twenty-five percent beyond seawater flooding.Contact angle measurements on carbonate,sandstone and shale cores indicate that wettability alteration and IFT decrease are the main oil-mobilizing mechanisms in the hybrid EOR process.The hybrid EOR process mobilizes part of the residual oil because:(i)low-salinity brine improves wettability towards hydrophilic condition favorable for surfactant flooding;(ii)surfactant in lowsalinity water solubilizes some of the remaining oil as Winsor type IImicroemulsion and lowers IFT between oil and water;and(iii)CO_(2) will follow surfactant to mobilize more of the remaining oil in the wettability-improved condition.展开更多
文摘Surfactant enhanced oil recovery(EOR)includes surfactant flooding and surfactant stimulation.The main functions of surfactants are to reduce interfacial tension and wettability alteration.This paper is to review the EOR technology related to surfactant injection.The reviewed topics include the following:Surfactant EOR mechanismsFactors affecting interfacial tension Trapping numberScreening criteriaLaboratory work Numerical simulation work Summary of pilot and large-scale applications Surfactants used Salinity gradientSurfactant EOR in carbonate reservoirs Surfactant EOR in shale reservoirs.
基金The authors are grateful to Abu Dhabi National Oil Company(ADNOC)and the Petroleum Institute(PI)at Abu DhabiMarathon Center of Excellence for Reservoir Studies(MCERS)and Center for Earth Materials,Mechanics,Characterization(CEMMC)at Colorado School of Mines(CSM)for their support of this study.
文摘Coreflood,interfacial tension(IFT),contact angle,and phase behavior measurements were performed to investigate the viability of a hybrid of low-salinity water,surfactant,and CO_(2) flood enhanced oil recovery(EOR)process.Low-permeability carbonate reservoir cores were aged for eight weeks at reservoir temperature and pressure.Coreflood and contact angle between oil droplets and core surface measurements were performed.Additional contact angle measurements on sandstone and shale cores were also performed.The coreflood sequences were seawater flood,followed by low-salinity water flood,followed by surfactant floods until residual oil saturations to each flooding sequences and finally CO_(2) injection.Coreflood in low-permeability carbonate cores show that the hybrid EOR process produces incremental oil up to twenty-five percent beyond seawater flooding.Contact angle measurements on carbonate,sandstone and shale cores indicate that wettability alteration and IFT decrease are the main oil-mobilizing mechanisms in the hybrid EOR process.The hybrid EOR process mobilizes part of the residual oil because:(i)low-salinity brine improves wettability towards hydrophilic condition favorable for surfactant flooding;(ii)surfactant in lowsalinity water solubilizes some of the remaining oil as Winsor type IImicroemulsion and lowers IFT between oil and water;and(iii)CO_(2) will follow surfactant to mobilize more of the remaining oil in the wettability-improved condition.
