Soil vapor extraction is a remediation method that establishes a vacuum in the subsurface soils. SVE method involves installing wells in the area of contamination. After installing the wells, the air from the blowers creates a vacuum on the wells.
The vacuum then creates the pressure that induces the flow of air and the removal of contaminants from the subsurface. The treatment of vapor recovered from the subsurface occurs above the ground, recovering or destroying the pollutants.
This method is appropriate for cleaning up volatile organic compounds such as gasoline. It often combines with other in-situ treatment technologies such as soil fracturing, air sparging, pump-and-treat.
There are various advantages of using SVE technology. As a non-intrusive method, it does not require site excavation or building demolition. However, the technology is highly dependent on the soil type.
Soil vapor extraction (SVE) is a cost-effective in-situ remediation technology used to clean up soil and shallow groundwater. This type of system is effective for cleaning up volatile organic compounds such as gasoline. Simply put, this technology applies a vacuum to the subsurface soils and sucks out the contaminants in the vapor phase for treatment above ground.
To start, SVE wells are installed in the area of contamination to a depth typically just above the high water table elevation. Once the wells are installed, they are connected to a blower which creates a vacuum on the wells. This vacuum induces air flow through the soil and causes the volatile organic contaminants to volatize or evaporate. This process can take anywhere from days to months to complete.
The vapors then enter an adjacent vapor treatment system where further remediation occurs.
This process reduces concentrations of volatile organic contaminants to levels that meet regulatory standards by controlling the movement and volatility of contamination and treating the contaminants as they escape from the soil.
Soil vapor extraction (SVE) is a remediation technology that can be used to control dissolved and volatile organic compounds in groundwater when coupled with others technologies such as air sparging. Air sparging bubbles air into the water table causing the dissolved contamination to volatize and migrate into the unsaturated soil where the SVE system removes and treats the contamination.
Vapor treatment systems may utilize activated carbon to filter out and adsorb the contamination. If the concentrations are too high for activated carbon, the contamination in the vapor stream can be destroyed using catalytic or thermal oxidizer units which basically burn off the contamination into carbon dioxide and water vapor.
One of the main advantages of using SVE technology is that the site does not need to be excavated allowing continued use of the property. Additionally, the contamination can be remediated underneath buildings without needing to demolish the building. The success of SVE technology is highly dependent on the soil type of the site and the contamination present and is not suitable for all sites.
