Potential of alkaline flooding to enhance heavy oil recovery through water-in-oil emulsification

► Alkaline flooding can improve sweep efficiency through water-in-oil emulsification. ► Improvement of sweep efficiency increases with the alkaline concentration. ► There is an optimum slug size that results in the highest tertiary oil recovery. ► The injection pattern is recommended to the continuous alkaline injection. ► There is an optimum injection rate that obtains the highest tertiary oil recovery.