Study on CO2 EOR and its geological sequestration potential in oil field around Yulin city

Abstract

Abstract Ordos Basin is enriched with oil and gas resources. It is the first largest low permeability petroliferous onshore basin in China with proved reserves more than 10×10 8 t. While most oil fields are suitable for applying CO 2 EOR and storage techniques, it provides good opportunity to reduce the country's energy intensity and amount of CO 2 emissions into the atmosphere. This study aimed at assessing the potential of CO 2 EOR and storage in Yulin surrounding areas within 300 km range based on the data of mature oil reservoirs. The Assessments including regional geology assessment, storage site screening, CO 2 EOR method, reservoir screening for CO 2 EOR and EOR potential and storage capacity calculations. The evaluation results demonstrate that oil fields in Yulin surrounding areas have good geographical and geological conditions for CO 2 storage. Of all 17 reservoirs, nine are suitable for CO 2 immiscible flooding and eight are suitable for CO 2 miscible flooding. The average incremental oil recovery ratios for immiscible and miscible flooding are 6.44% and 12% respectively. Total EOR potential is 8×10 7 t and CO 2 storage capacity could reach 1.3×10 8 t.