Long core physical simulation for CO2 flooding in low permeability reservoir

CO 2 flooding is a proven great method to be used for enhancing injection capacity and increasing oil production in low permeability reservoir. In this paper, based on the natural cores and crude oil of Jilin oilfield, three sets of long core tests were conducted to study oil recovery, GOR and pressure variations during water flooding and CO 2 flooding. The performance of advanced CO 2 injection, simultaneous CO 2 injection and water injection were compared to optimise injection opportunity and injection pattern for low permeability reservoir. Results indicate that advanced CO 2 injection is better in maintaining reservoir pressure and improving displacement efficiency. It is considered that advanced CO 2 injection before oil production supply valuable opportunity for CO 2 to fully contact with oil which could help decrease oil viscosity and interfacial tension, swell oil volume and increase injection rate effectively.