Heat it all the way
A key to success within thermal soil remediation is the ability to apply heat in a thorough, robust and predictable way. If you are not able to “heat it all the way” the chances for failure is increasing. For that reason we have chosen to work with two main technologies:
Thermal Conductive Heating (TCH)
In all its simplicity it is about transferring energy into the subsoil by thermal conduction. Heating of all kind of soils are highly predictable and efficient because the thermal conduction for the entire range of soils is almost equal. This allows uniform heating and effective remediation of fine-grained material like clay, silt as well as inhomogeneous deposits and even bedrock.
Thermal conduction this is the only heating technology that can heat the subsurface from low to high temperatures and hence treat a very broad specter of contaminants from VC to PAH, PCB and Dioxin.
Using electrical powered heater elements installed in traditional steel borings we are able to supply these with energy from renewable sources like wind- or hydro energy. Furthermore the electrical system deliver the energy to the subsurface with almost 100% efficiency.
We have since 2006 chosen to work with TerraTherm Inc. using their patented heating technology. We believe that TerraTherm’s approach to the thermal soil remediation is in line with our vision.
Steam Enhanced Extraction
At some sites there are portions of the sites that are very permeable and water yielding.
Whenever sites have high water yielding aquifers there might be challenges with reaching the treatment temperature because the flowing water removes more energy than injected. This is where we either use or supply the heating techniques with Steam Enhanced Extraction (SEE).
With SEE it is possible to inject significant more energy from fewer wells. With SEE you are even capable of creating a steam bubble that stops water from flowing into the treatment zone. Since SEE relies on hydraulic conduction it is more challenging and hence it is important to have the expertise and knowledge with hydrogeology to design and implement the technology. Combining TCH and SEE gives the most robust and successful thermal remediation approach capable of handling almost all situations.