Polymer flooding enhances oil recovery from an oil reservoir by
Show Hint
- increasing the mobility ratio
- reducing the mobility ratio
- reducing the viscous fingering
- increasing the viscous fingering
The Correct Option is B
Solution and Explanation
- The primary objective is to increase the viscosity of water, thereby improving the mobility ratio.
- The mobility ratio is the ratio of displacing fluid mobility (water) to displaced fluid mobility (oil). A high mobility ratio means water moves faster than oil, bypassing much of the oil.
- By adding polymers, water becomes more viscous, which reduces the mobility ratio, leading to more uniform displacement of oil.
- This also helps in reducing viscous fingering, where water channels through oil zones unevenly, leaving behind unrecovered oil.
- Therefore, polymer flooding works by (B) reducing the mobility ratio and (C) reducing viscous fingering.
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