Artificial Lift

Artificial lift involves the use of artificial means to increase the flow of liquids, such as crude oil or water, to the surface of a production well. Generally this is achieved by a mechanical device inside the well, such as a pump; decreasing the weight of the liquid/gas mixture via high pressure gas; or improving the lift efficiency of the well via velocity strings. Artificial lift is needed in wells when there is insufficient pressure in the reservoir to lift the liquid to the surface, but often used in naturally flowing wells (which don't technically need it) in order to increase the flow rate above what would flow naturally. The produced fluid can be oil and/or water, typically with some amount of gas included. The artificial lift provides additional energy to the system such that the fluids can be lifted to surface.
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