Community Research and Development Information Service - CORDIS

Decontaminating pesticides in soils

The decontamination of soils polluted with obsolete pesticides has become possible with the integrated Thermal Desorption Technology and biological revitalisation treatment.
Decontaminating pesticides in soils
The contamination of soils from complex compounds of obsolete pesticides is a common problem both at former production sites as well as improper storage facilities and their surroundings. These toxic substances accumulate, reaching increased levels of concentration, while they penetrate the soil matrix. Eventually, such pesticide contamination suspends utilisation of valuable land, decreasing agricultural production, while it pollutes groundwater, exposing humans and animals to toxicity dangers.

Furthermore, the complex nature of pesticides means that existing decontamination methods are not viable as they are not only costly, but also have unpredictable results.

For soil decontamination to be efficient a new method has been developed, involving low temperature thermal decomposition of the contaminated soil, which is processed in indirectly heated vessels. A mobile unit has been designed and constructed for field and full-scale demonstration with a throughput capacity of 1m3/h.

The developed process involves the following stages. Gentle removal of volatile contaminations is achieved with a truly reductive environment in a vacuum, that does not allow for the treated soils to be oxidised or for the inorganic components to be changed. Gas vapours are then burned at high temperature, off-gas is cleansed, while the solid phase is denaturalised by Thermal Desorption Technology Recycle-Reduce-Reuse Terra Humana (TDT-3R) integrated biological revitalisation by determined microbiological species for comprehensive post-processing. The main component of the TDT-3R is a specially designed, indirectly fired kiln reactor.

The main advantages of this method, which is still at the experimental development stage, with the laboratory prototype complete, involve the exact predictability and short time of the decontamination procedure. This allows fast capitalisation of the cleansed land as well as a solution to the owner’s legal responsibility for ground pollution, providing guaranteed results and corresponding full legal acceptance of the decontamination procedure. Finally, environmental benefits are greatest, as it provides an immediate solution to the pollution of the groundwater from obsolete pesticides.

Related information

Record Number: 80454 / Last updated on: 2005-09-18
Domain: Environment