Volume 25: Accelerated Energy Innovations and Emerging Technologies

Optimization and Evaluation of CO2 Storage and Enhanced Oil Recovery in Low Permeability Reservoir Xiaochen Wang, Xinwei Liao, Kang Tang, Peng Dong

Abstract

In low permeability reservoirs, poor water injection development effect, high water injection pressure, formation energy can not be effectively supplemented and other problems often lead to unsatisfactory development effect, so it is a big problem to change the development mode to improve oil recovery. The injection of carbon dioxide into the reservoir and geological storage of the injected CO2 can greatly reduce the viscosity of crude oil, improve the fluidity of the oil, and reduce the oil seepage resistance, thus improving the development effect and enhancing the oil recovery. Yesanbo oilfield is located in the south of Dagang oilfield, which is a typical low permeability reservoir. Considering the dual advantages of carbon dioxide geological storage and enhanced oil recovery, this paper chooses this area for reservoir numerical simulation study. Based on the mechanism model, the number of injection Wells, injection velocity, Ratio of vertical to horizontal permeability (Kv/Kh), The influence of critical water saturation value on carbon capture ， utilization and storage (CCUS) scheme operation. The results show that a horizontal well with two straight gas injection Wells is the best. The higher the gas injection rate, the greater the carbon storage and cumulative oil production. When Kv/Kh value increases, the carbon storage decreases, and the cumulative oil production increases. Critical water saturation value increases cumulative oil production and carbon storage decreases. The CCUS scheme constructed in Yesanpu oilfield has dual functions of oil displacement and carbon sequestration, which significantly improves oil recovery and deposits a considerable amount of carbon dioxide into the reservoir. This study provides a scientific basis for the operation of CCUS in the oilfield.

Keywords geological storage of carbon dioxide, enhanced oil recovery, low permeability reservoir