Abstract
In South China Sea, the geological reserve of CO2 is huge. With the unanimous agreement of a series of problems caused by CO2 emissions, as an effective method to consume CO2, CO2 injection for enhanced oil recovery (EOR) has been investigated and reported by many researchers.
An extensive review of previous reported CO2-EOR projects is provided in this paper. According to exploring and analyzing the factors influencing CO2-EOR, and combined with the specialty of offshore conditions, reservoir evaluation of China offshore CO2-EOR is suggested in this paper. Based on the evaluation suggestion, the Chinese offshore oilfields were screened and the South China offshore oilfield close to CO2 reserve was conformable. This paper also describes the feasibility of CO2-EOR in the South China offshore oilfield from fundamental studies. The relationship of reservoir oil and CO2 showed that reservoir oil had good dissolving capacity to CO2. CO2 could effectively dissolve in and displace residual oil. The experimental results show that under reservoir conditions, CO2 could be in the one-contact miscible at 20 MPa, a slight higher than the formation pressure of 17.27 MPa. CO2 and oil could be in near miscible under formation conditions. The lab research work funded a further investigation on application of CO2-EOR in China offshore oilfield.