In situ steam extraction

Two types of in situ steam extraction systems, mobile and stationary, are available. The mobile system may have rotating cutter blades that release steam as they tunnel through the soil. This system treats small areas sequentially. The stationary system injects the steam into drilled wells, without disturbing the soil. 

The stationary in situ steam extraction system uses injection wells to introduce the steam, and recovery wells for removing it. Soil permeability is a major factor. Low-permeability soils require a far greater number of wells compared to high-permeable soil, driving up costs. To be effective... 

Steam extraction has been used for gasoline and diesel fuel. High-molecular-weight components of the diesel fuel cannot be removed easily, although a total removal of up to 91% is possible. When used to remove low-volatility compounds in a soil with a high percentage of clay, performance is expected to be ca. 85%. The mobile in situ steam extraction system can reduce VOCs in soils by more than 50% of their initial level. Based on pilot studies, the stationary steam extraction system is expected to have a 90% removal efficiency.54... 

The vendor for this technology is no longer in the environmental cleanup business. However, this technology is available from a number of vendors, and a summary of the technology in general is available in T0407, In Situ Steam Extraction—General. 

T0407 In Situ Steam-Enhanced Extraction—General... 

T0406 In Situ Soil Vapor Extraction (SVE)—General T0407 In Situ Steam-Enhanced Extraction—General... 

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