CO2 assisted steam flooding in late steam flooding in heavy oil reservoirs

XI Changfeng,QI Zongyao,ZHANG Yunjun,LIU Tong,SHEN Dehuang,MU Hetaer,DONG Hong,LI Xiuluan,JIANG Youwei,WANG Hongzhuang

Fig. 4. Production dynamic curve of CO2-assisted steam flooding after steam flooding and perforation adjustment. ① Steam flooding at steam injection rate of 80 mL/min; ② CO2-assisted steam flooding at steam injection rate of 65 mL/min and CO2 injection rate of 200 mL/min; ③ CO2-assisted steam flooding at the steam injection rate of 50 mL/min and the CO2 injection rate of 250 mL/min for; ④ CO2-assisted steam flooding at the steam injection rate of 50 mL/min and the CO2 injection rate of 380 mL/min; ⑤ CO2-assisted steam flooding at the steam injection rate of 30 mL/min and CO2 injection rate of 380 mL/min.