Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosity
Based on physical simulation of water-flooding homogeneous reservoirs, the water-flooding characteristics of homogeneous reservoirs with different oil viscosity are examined at different oil recovery rate. Reservoirs with low-viscosity (<5 mPa·s) oil can be evenly swept, with thick streamline. Wi...
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| Format: | Article |
| Language: | English |
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KeAi Communications Co., Ltd.
2015-06-01
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| Series: | Petroleum Exploration and Development |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S187638041530029X |
| _version_ | 1818956452063084544 |
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| author | Lun ZHAO Xi CHEN Li CHEN Renyi CAO Xiangzhong ZHANG Jia LIU Fachao SHAN |
| author_facet | Lun ZHAO Xi CHEN Li CHEN Renyi CAO Xiangzhong ZHANG Jia LIU Fachao SHAN |
| author_sort | Lun ZHAO |
| collection | DOAJ |
| description | Based on physical simulation of water-flooding homogeneous reservoirs, the water-flooding characteristics of homogeneous reservoirs with different oil viscosity are examined at different oil recovery rate. Reservoirs with low-viscosity (<5 mPa·s) oil can be evenly swept, with thick streamline. With increasing oil recovery rate, water rush weakens along the reservoir bottom and sweeps the reservoir more evenly in the vertical direction; and the sweep efficiency difference between top and bottom of the reservoir decreases. In high-rate development of the low-viscosity oil reservoir, the water-free recovery percent is significantly higher than that in low-rate development, and the rising velocity of water cut is lower than that under low-rate development, which proved that such reservoirs are suitable for high-recovery-rate development. For reservoirs with medium-high viscosity (5−50 mPa·s) oil, the injected water fingers significantly in the water-flooding process, with thin streamline, the coverage is not swept completely, especially in area between streamlines, the sweep efficiency difference between top and bottom is great. As the oil recovery rate increases, the streamline becomes thinner, the coverage becomes more incomplete, and the sweep efficiency of top and bottom both decreases. Medium to high-viscosity oil reservoirs developed at high rate have a short water breakthrough time, and the recovery percent in the water-free period is much lower than that in low rate development, and the rising velocity of water cut is higher than that under low-rate development, so high-rate development is not adaptable for medium-high viscosity reservoirs. Key words: water-flooding experiment, homogeneous reservoir, oil viscosity, oil recovery rate, water-flooding law, injected water sweep characteristics, high-rate development adaptability |
| first_indexed | 2024-12-20T10:54:10Z |
| format | Article |
| id | doaj.art-41cb689d3ebe4896b54bdcce2a984662 |
| institution | Directory Open Access Journal |
| issn | 1876-3804 |
| language | English |
| last_indexed | 2024-12-20T10:54:10Z |
| publishDate | 2015-06-01 |
| publisher | KeAi Communications Co., Ltd. |
| record_format | Article |
| series | Petroleum Exploration and Development |
| spelling | doaj.art-41cb689d3ebe4896b54bdcce2a9846622022-12-21T19:43:11ZengKeAi Communications Co., Ltd.Petroleum Exploration and Development1876-38042015-06-01423384389Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosityLun ZHAO0Xi CHEN1Li CHEN2Renyi CAO3Xiangzhong ZHANG4Jia LIU5Fachao SHAN6PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China; Corresponding authorPetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, ChinaPetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, ChinaChina University of Petroleum (Beijing), Beijing 102249, ChinaPetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, ChinaChina University of Petroleum (Beijing), Beijing 102249, ChinaPetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, ChinaBased on physical simulation of water-flooding homogeneous reservoirs, the water-flooding characteristics of homogeneous reservoirs with different oil viscosity are examined at different oil recovery rate. Reservoirs with low-viscosity (<5 mPa·s) oil can be evenly swept, with thick streamline. With increasing oil recovery rate, water rush weakens along the reservoir bottom and sweeps the reservoir more evenly in the vertical direction; and the sweep efficiency difference between top and bottom of the reservoir decreases. In high-rate development of the low-viscosity oil reservoir, the water-free recovery percent is significantly higher than that in low-rate development, and the rising velocity of water cut is lower than that under low-rate development, which proved that such reservoirs are suitable for high-recovery-rate development. For reservoirs with medium-high viscosity (5−50 mPa·s) oil, the injected water fingers significantly in the water-flooding process, with thin streamline, the coverage is not swept completely, especially in area between streamlines, the sweep efficiency difference between top and bottom is great. As the oil recovery rate increases, the streamline becomes thinner, the coverage becomes more incomplete, and the sweep efficiency of top and bottom both decreases. Medium to high-viscosity oil reservoirs developed at high rate have a short water breakthrough time, and the recovery percent in the water-free period is much lower than that in low rate development, and the rising velocity of water cut is higher than that under low-rate development, so high-rate development is not adaptable for medium-high viscosity reservoirs. Key words: water-flooding experiment, homogeneous reservoir, oil viscosity, oil recovery rate, water-flooding law, injected water sweep characteristics, high-rate development adaptabilityhttp://www.sciencedirect.com/science/article/pii/S187638041530029X |
| spellingShingle | Lun ZHAO Xi CHEN Li CHEN Renyi CAO Xiangzhong ZHANG Jia LIU Fachao SHAN Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosity Petroleum Exploration and Development |
| title | Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosity |
| title_full | Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosity |
| title_fullStr | Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosity |
| title_full_unstemmed | Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosity |
| title_short | Effects of oil recovery rate on water-flooding of homogeneous reservoirs of different oil viscosity |
| title_sort | effects of oil recovery rate on water flooding of homogeneous reservoirs of different oil viscosity |
| url | http://www.sciencedirect.com/science/article/pii/S187638041530029X |
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