Physical simulation of exploiting fractured-vuggy carbonate gas condensate reservoirs by water injection

Due to the development of fissures and cavities with different sizes and shapes, fractured-vuggy carbonate gas condensate reservoirs are distinct from the general sand gas condensate reservoirs, hence are characterized by strong heterogeneity and complicated flow regularity. To these reservoirs, it is a question of concern that which developing strategy is benefit to maximize the recoveries of oil and gas. As a mature technology, water injection possesses advantages such as lower cost, better gas-water mobility ratio, and higher sweep efficiency. Taking well TZ86 as a target, we accomplished a physical simulation research under initial reservoir conditions (140.6 ℃,58 MPa) by using an artificial fractured-vuggy full-diameter core which was made from an outcrop of carbonate rock. The experimental results show that the effectiveness of exploiting fractured-vuggy carbonate gas condensate reservoirs by water injection is significant. The factors such as the connectivity pattern between fissure and cavern, the pressure maintenance level of water injection, and cavern whether or not filling have effects on the recovery of condensate oil.