A Simulation Approach for Screening of EOR Scenarios in Naturally Fractured Reservoirs

Abstract

Undoubtedly, plenty of hydrocarbon sources are located in carbonate rocks, particularly those which are naturally fractured that is still needed to study their characterization, because of their complex and unconventional behavior. Therefore, applying any processes that cause Enhancing Oil Recovery (EOR) from Naturally Fractured Reservoirs (NFR) seems necessary and useful. However, selecting the best developed scenario is always challenging. Screening criteria would determine the possibility of implementing an EOR process. While, utilizing trade marketing simulators can solve this problem. Moreover, simulation can evaluate other parameters such as water cut and gas-oil ratio. In this research, an aquifer-supported Iranian NFR with two parts that are separated to each other with a shale layer is considered in order to select the best EOR scenario. The fluid model is created using PVTi software. Various production scenarios included natural depletion, water flooding, miscible carbon dioxide injection, water-alternating-gas (WAG) injection, simultaneous water-alternating-gas (SWAG) injection, hybrid injection, and gas recycling are simulated in ECLIPSE Compositional (E300) and their recovery factor recorded as the target parameter. The developed scenarios are designed in a way that gives the optimized results, i.e. higher recovery factor, less water cut as well as the less gas-oil ratio. As a result, SWAG shows better conditions and is recommended for the further studies of the reservoir management plan in the future. Also, the role of the aquifer in the SWAG scenario is positive by creating a natural WAG in addition to the SWAG. Additionally, the average reservoir pressure through fractures reduces less in the SWAG than the other Scenarios, the oil and gas production rate reduce less in the SWAG and SWAG/ miscible gas respectively than the other scenarios. The maximum and the minimum water cut are related to the water flooding and SWAG, respectively.

Modeling Interfacial Tension of N2/CO2 Mixture + n-Alkanes with Machine Learning Methods: Application to EOR in Conventional and Unconventional Reservoirs by Flue Gas Injection

“…To produce crude oil from a reservoir, three methods are available: primary, secondary, and tertiary or enhanced oil recovery (EOR). EOR is a way to produce reducible oil in the reservoir which is defined as a set of techniques and processes that increases the amount of oil recovery by employing energy and the injection of materials [1][2][3]. Improved oil recovery (IOR) and EOR are used to increase the recovery factor of remained oil in reservoirs.…”

“…Herein, the reduction of interfacial tension (IFT) can help to increase EOR by removing the trapped oil. Moreover, it can increase the two-phase miscibility and improve oil recovery [2,3]. EOR is divided into several methods, such as gas injection, chemical EOR, thermal EOR, and other new technologies.…”