Definition - What does Injection Well mean?
An injection well is a device that helps to place fluids underground in porous rock formations like limestone and sandstone, or below the shallow soil layer. The fluids can be wastewater, brine, or water mixed with chemicals.
Deep injection wells are also known as class 2 underground injection wells. These wells are used to dispose of wastewater that contains salt, chemicals, radioactive materials or heavy metals.
Corrosionpedia explains Injection Well
The construction of an injection well depends upon the well's depth and the type of fluid being injected. Injection wells are constructed to offer multiple layers of protective cement and casing. Shallow wells, in contrast, usually have a simple construction.
Injection wells are used to enhance oil production, store carbon dioxide, dispose of wastewater and prevent saltwater intrusion. They are also used in mining.
There are two main types of injection:
- Gas - The imported gas or separated gas from the production wells is injected into the upper section of the reservoirs that contain gas.
- Water - Treated and filtered seawater is injected into the lower section of the reservoirs bearing water. Water injection wells are usually located at offshore sites.