Survey on the Effect of Existent Impurities in Sour Gas Produced from Phases 6, 7 and 8 of South Pars Gas Complex in order to Inject to the Reservoir of Aghajari Oil Field

Since the pressure of hydrocarbon reservoirs drops due to production, in orderto keep the production rate constant or increase enhanced recovery, few methods are used. One of which is gas injection to the reservoir. On the other hand, due to reduction in oil production potential of Aghajari oil field, gas injection is highly required to pressurize and enhance oil recovery. There is a possibility to transfer a part of South Pars Common field produced gas to Aghajari oil district via pipeline to inject it into that reservoir. Produced gases of phases 6, 7 and 8 of South Pars gas reservoir contain impurities such as carbon dioxide (CO2), nitrogen (N2), hydrogen sulfide (H2S) and water vapor (H2O). In this research, the effect of injection of the produced sour gas from phases 6, 7 and 8 of South Pars Complex, on minimum miscibility pressure is investigated by compositional simulation method and using CMG software, considering sour gas composition. The yielded results show that minimum miscibility pressure will increase considerablyif both acidic gases, H2S and CO2 are stripped from the injected gas.