Applying Thermal Desorption
A Mature Technology that Just Works
Operational experience of over 125 mobile soil remediation projects has allowed Midwest Soil Remediation to build an extensive database of treated soil residual concentrations. As a rule of thumb, most contaminants can be reduced to less than 1.0 mg/kg (ppm) if the starting level is less than 500 mg/kg. Another way to make a preliminary estimate is to assume a removal efficiency of 98 to 99.99%.
Typical Contaminant Reduction
- Most volatile organic compounds and solvents can easily be reduced to less than 0.1 mg/kg and frequently to below 0.01 mg/kg.
- Most semi-volatile compounds can be reduced to less than 1.0 mg/kg and frequently to less than 0.1 mg/kg.
- The various PCB Aroclors can be reduced to less than 2.0 mg/kg and frequently to less than 0.5 mg/kg.
- Most pesticides will have a 99.5 to 99.99% removal.
The treated soil is usually backfilled in to the excavation. The material compacts well and most compaction specifications can be met.
Basis for Selecting a Treatment System
Just about any media can be treated with thermal desorption to remove organic contaminants. So, thermal desorption will work in most cases, but is it the correct choice for your site? The following characteristics of a site will determine how suitable thermal desorption is for your project.
- Quantity of material requiring treatment
- Types and concentrations of contaminants
- Material classification – Hazardous, special waste, or non-hazardous
- Physical characteristics of the material
- Cleanup objectives
- Site logistics
Thermal desorption units come in various sizes and configurations. Once we understand the characteristics of a site, a suitable unit can be proposed. Thermal desorption units can be direct fired, indirect fired and either be continuous flow or a batch type processor.