Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its Challenges
Unlocking oil from tight reservoirs remains a challenging task, as the existence of fractures and oil-wet rock surfaces tends to make the recovery uneconomic. Injecting a gas in the form of a foam is considered a feasible technique in such reservoirs for providing conformance control and reducing ga...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-04-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/14/7/1998 |
| _version_ | 1797538748314943488 |
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| author | Haishan Luo Kishore K. Mohanty |
| author_facet | Haishan Luo Kishore K. Mohanty |
| author_sort | Haishan Luo |
| collection | DOAJ |
| description | Unlocking oil from tight reservoirs remains a challenging task, as the existence of fractures and oil-wet rock surfaces tends to make the recovery uneconomic. Injecting a gas in the form of a foam is considered a feasible technique in such reservoirs for providing conformance control and reducing gas-oil interfacial tension (IFT) that allows the injected fluids to enter the rock matrix. This paper presents a modeling strategy that aims to understand the behavior of near-miscible foam injection and to find the optimal strategy to oil recovery depending on the reservoir pressure and gas availability. Corefloods with foam injection following gas injection into a fractured rock were simulated and history matched using a compositional commercial simulator. The simulation results agreed with the experimental data with respect to both oil recovery and pressure gradient during both injection schedules. Additional simulations were carried out by increasing the foam strength and changing the injected gas composition. It was found that increasing foam strength or the proportion of ethane could boost oil production rate significantly. When injected gas gets miscible or near miscible, the foam model would face serious challenges, as gas and oil phases could not be distinguished by the simulator, while they have essentially different effects on the presence and strength of foam in terms of modeling. We provide in-depth thoughts and discussions on potential ways to improve current foam models to account for miscible and near-miscible conditions. |
| first_indexed | 2024-03-10T12:35:49Z |
| format | Article |
| id | doaj.art-7a02a2eca0554d7c910fa198371dbf38 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T12:35:49Z |
| publishDate | 2021-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-7a02a2eca0554d7c910fa198371dbf382023-11-21T14:15:03ZengMDPI AGEnergies1996-10732021-04-01147199810.3390/en14071998Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its ChallengesHaishan Luo0Kishore K. Mohanty1Center for Subsurface Energy and the Environment, The University of Texas at Austin, Austin, TX 78712, USACenter for Subsurface Energy and the Environment, The University of Texas at Austin, Austin, TX 78712, USAUnlocking oil from tight reservoirs remains a challenging task, as the existence of fractures and oil-wet rock surfaces tends to make the recovery uneconomic. Injecting a gas in the form of a foam is considered a feasible technique in such reservoirs for providing conformance control and reducing gas-oil interfacial tension (IFT) that allows the injected fluids to enter the rock matrix. This paper presents a modeling strategy that aims to understand the behavior of near-miscible foam injection and to find the optimal strategy to oil recovery depending on the reservoir pressure and gas availability. Corefloods with foam injection following gas injection into a fractured rock were simulated and history matched using a compositional commercial simulator. The simulation results agreed with the experimental data with respect to both oil recovery and pressure gradient during both injection schedules. Additional simulations were carried out by increasing the foam strength and changing the injected gas composition. It was found that increasing foam strength or the proportion of ethane could boost oil production rate significantly. When injected gas gets miscible or near miscible, the foam model would face serious challenges, as gas and oil phases could not be distinguished by the simulator, while they have essentially different effects on the presence and strength of foam in terms of modeling. We provide in-depth thoughts and discussions on potential ways to improve current foam models to account for miscible and near-miscible conditions.https://www.mdpi.com/1996-1073/14/7/1998foam injectionfractured rockoil-wet rockfoam modelgas compositionmiscible foam |
| spellingShingle | Haishan Luo Kishore K. Mohanty Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its Challenges Energies foam injection fractured rock oil-wet rock foam model gas composition miscible foam |
| title | Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its Challenges |
| title_full | Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its Challenges |
| title_fullStr | Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its Challenges |
| title_full_unstemmed | Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its Challenges |
| title_short | Modeling Near-Miscible Gas Foam Injection in Fractured Tight Rocks and Its Challenges |
| title_sort | modeling near miscible gas foam injection in fractured tight rocks and its challenges |
| topic | foam injection fractured rock oil-wet rock foam model gas composition miscible foam |
| url | https://www.mdpi.com/1996-1073/14/7/1998 |
| work_keys_str_mv | AT haishanluo modelingnearmisciblegasfoaminjectioninfracturedtightrocksanditschallenges AT kishorekmohanty modelingnearmisciblegasfoaminjectioninfracturedtightrocksanditschallenges |