OPTIMIZATION OF CARBON DIOXIDE SEQUESTRATION AND ENHANCED OIL RECOVERY IN OIL RESERVOIR

Carbon dioxide (CO2) storage into depleted or partially depleted oil reservoirs is an immediate option to reduce CO2 emissions into the atmosphere. This process, if implemented in depleted oil reservoirs, combines environmental benefits by reducing CO2 concentration in the atmosphere and economical benefits by maximizing oil recovery. CO2 oil recovery processes, to date, have attempted to minimize the amount of CO2 needed to recover each barrel of oil. For a sequestration process, however, the aim is to maximize both the amount of oil produced and the amount of CO2 stored. As part of this process, significant quantities of CO2 remain to be sequestered in the reservoir. If CO2 emissions are regulated, EOR process may therefore be able to earn sequestration credits in addition to oil revenues. This paper discusses the effects of several injection strategies and injection timing on optimization of oil recovery/CO2 storage capacity for a synthetic, three dimensional, heterogeneous reservoir models. A simulation study was completed using a 3‑D compositional simulator "ECLIPSE 300" in order to optimize oil recovery and CO2 storage. The simulation study proceeded through the following steps: 1) comparison of different injection schemes; 2) testing the effect of injection timing on the CO2 storage capacity. The results show that innovative reservoir engineering techniques are required for co‑optimizing CO2 storage and oil recovery.