In-Situ Thermal Technology
Fast and effective treatment of lasting contamination
In-Situ Thermal Remediation is often the most effective treatment for lasting contamination, achieving strict contaminant reduction targets faster than alternative technologies.
It works well on sites with complex geologies – such as fractured rock or where there are multiple sand lenses within clays – and on operational sites where excavation of soils is not viable.
Through our exclusive partnership with Canadian specialists McMillan-McGee Corp, we’re able to provide unrivalled in-situ thermal technology to UK projects.
Electro Thermal Dynamic Stripping Process (ET-DSP)
TM
How It Works
McMillan-McGee (Mc2)’s patented ET-DSPTM thermal heating process introduces electrical current into contaminated soil via electrodes, which are strategically placed throughout a contaminated zone.
Using three-phase power, it transfers current to each individual electrode and heats the subsurface.
The heat transfer mechanism volatilises contaminants in-situ or drives them to extraction wells via. a guided steam front.
Electrical heating increases the temperature of the soil and groundwater by conducting current through the interstitial water that fills the porosity voids in soil.
Why it’s more effective than rival technologies
ET-DSPTM benefits from the three dominant mechanisms of heat transfer:
- Conduction
- Convection
- Electrical heating
Application of convective heating, accomplished by injecting water at controlled rates into the ends of the electrodes where the electrical field has the highest density, makes ET-DSPTM more effective than rival technologies.
Without convective heat transfer, conventional remediation processes are limited by retardation of the contaminant in-situ, especially in fine sediments and clays.
This means primary technologies must be operated for long periods and may not achieve clean-up standards in low-permeability soils or where the vapor pressure of the contaminant is low.
The process can take years, whereas ET-DSPTM achieves a significant reduction in contaminant within 3 to 8 months. So far, it has been used successfully on >140 sites worldwide.