Impact of physical phenomena and cyclical reinjection in miscible CO2-WAG recovery in carbonate reservoirs

Carbonated reservoirs with high percentage of CO 2 have been discovered and produced in the Brazilian pre-salt cluster. Recovery techniques, such as CO 2 -WAG, have hence been evaluated and applied, as in the Lula field. Although studies demonstrate the advantages of this technique, it is still difficult to estimate an increase in oil recovery. Thus, this work presents a methodology to evaluate the impacts of the main phenomena that occur and how CO 2 recycling can benefit the management of these fields. The results showed an increase in recovery with the modeling of the main phenomena such as relative permeability hysteresis and aqueous solubility of CO 2 , accompanied by a significant increase in CO 2 injection. However, the recycling of the CO 2 produced was shown to be fundamental in the reduction in this injection and to increase the NPV. The results showed a 4% increase in oil production and 9% in NPV, considering a producer–injector pair.