For several decades, CO2 injection has been used as a successful recovery method in enhanced oil recovery. The main impact of CO2 is on lowering minimum miscibility pressure (MMP). Reaching the miscibility pressure is often limited by the reservoir pressure and temperature. Based on the earlier studies, lowering the temperature of the medium by the injection fluid may help in a decrease of MMP, resulting in miscible flooding. However, the proposed method should be determined by experimental procedures and numerical calculation. For the evaluation of MMP reduction and the limitations involved, the slimtube displacement experiments were used along with simulation runs. Then the results were compared with empirical correlations. The results showed that injection of low temperature CO2 (LCO2) has a direct impact on the MMP of a high temperature system. However, it limited when the injection temperature is below the critical temperature of CO2. A modification equation was presented to be applied on available empirical correlations. In terms of MMP, LCO2 injection is more beneficial than CO2 when it enters the reservoir at lower temperatures with respect to injection limitations.

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