The IEG-LNAPL removal system (FLE) is applied to remove LNAPL from the groundwater. It is not necessary to pump groundwater from the recovery well in order to create a cone a depression which makes a separate and expensive groundwater treatment obsolete.
Description of Method:
Negative pressure created by a blower is applied to a specially designed well. Soil air being pulled into the recovery well and the negative pressure in and around the well lead to a transport of the LNAPL towards the recovery well. To facilitate the movement of soil air and LNAPL active or passive injection well can be placed around the recovery well. In the recover well a floating phase-separating filter is positioned, which separates the LNAPL from the groundwater. The LNAPL is sucked from the LNAPL/water interface and collected in a collection vessel. This collection vessel also acts as an oil-water separator to separate small droplets of water that are occasionally also being pulled in. The off-gas is treated with activated carbon or other filter devices.
Advantages of the IEG-LNAPL Removal System (FLE):
- To mobilize the LNAPL towards the recovery well no groundwater extraction is necessary, no groundwater treatment or disposal is needed
- Contamination of deeper portions of the aquifer by the creation of a cone of depression can be avoided
- When the LNAPL is being pulled to the surface, emulsions are not formed, small droplets of water that are also lifted up settle gravitationally
