MODEL-BASED OPTIMIZATION OF CYCLES OF CO2 WATER-ALTERNATING-GAS (CO2-WAG) INJECTION IN CARBONATE RESERVOIR

Pre-salt reservoirs are among the most important discoveries in recent decades due to large quantities of oil them. However, high levels uncertainties related its gas/CO2 production prompt a more complex management, including use alternating water and injection (WAG) as recovery mechanism increase from field. The purpose this work is develop methodology manage cycle sizes WAG/CO2, analyze impact other variables management producing wells during process. was applied benchmark synthetic reservoir model with pre-salt characteristics. We used five approaches evaluate optimum size under study, also assessing wells: (A) without closing producers gas-oil ratio (GOR) limit; (B) GOR limit fixed at value (1600 m³/m³) for all wells; (C) optimized per well; (D) joint optimization between values WAG cycles; (E) injector well an limit. results showed that depends on producers. Leaving open until end field's life (without based limit) or controlling restricted manner (with limit), led significant variation (optimal WAG/CO2 cycles). Our therefore, demonstrates control can change significantly these variables. This presents study aimed WAG-CO2 by optimizing obtain better economic performance within premises already established, such total reinjection produced, analyzing (management wells) along cycles.