Perpustakaan Digital ITB

Injecting carbon dioxide (CO2-EOR) is an effective method to increase oil recovery while storing carbon underground. Using gas streams that still contain impurities helps eliminate the high cost of gas purification facilities. This study uses reservoir simulation in tNavigatorTM to evaluate how impure CO2 injection affects oil production and CO2 sequestration in the Norne Field. A compositional model using the Peng-Robinson Equation of State (PR-EOS) was developed and calibrated through history matching with an initial fluidin-place error below 1%. Minimum Miscibility Pressure (MMP) was tested for gas mixtures containing H2S, C1, and N2. The results show that reservoir pressure remained above the MMP in all cases, maintaining miscible displacement. Scenario 4 (85% CO2 & 15% H2????), which has the lowest MMP, achieved the highest oil recovery, and recovery factor decreased consistently with increasing MMP across all CO2 – based scenarios, except for one pair whose MMP difference falls within the uncertainty of the tieline method. Meanwhile, although Scenario 2 (100% CO2) stored the largest absolute volume of CO2, this was primarily because it injected the largest volume of CO2 overall; when normalized against the volume injected, Scenario 8 (85% CO2 & 15% N2) retained the largest fraction of CO2, with structural trapping and solubility trapping in oil acting as the two dominant trapping mechanisms across all scenarios. This study shows that oil production and carbon storage can be optimized together without needing expensive gas purification.