In times when the reallocation of brownfield sites is at least an equivalent alternative to using greenfield sites, soil remediation is more crucial than ever. During the removal of any contaminated soil, activated carbon can play an essential role in controlling air pollution and odour emissions. Desotec recently proved this with a project in France.

To give sites of former industrial factories a new purpose, environmental experts first and foremost look at the composition of the soil. It is often contaminated with chemical components. Therefore, remediation companies approach such projects with caution and surround themselves with specialised partners. They are also essential to nip the odour emissions that may arise during the remediation process in the bud.

Some time ago, a remediation company in France was commissioned to clean the soil of a former industrial site. The analysis of the soil determined that it was mainly contaminated with trichloroethylene (TCE). This product was once popular with dry cleaners that wanted to remove stains from carpets and clothing. Before it became known that the substance also had hazardous properties, it was regularly used as gas for anaesthesia.

During the remediation work on-site, the remediation company decided to use a tent installation. It was essential to properly protect the users inside the tent as well as the surrounding area, and further crucial to enable proper filtration of the air flows. This was also required since the concentration of trichloroethylene was more than 2,000 ppm, while it could not exceed 2 ppm for the work at the construction site to continue.

The company had previously collaborated with Desotec for effective water and air treatment in remediation projects and once again decided to avail themselves of Desotec's services for this case. After a thorough analysis, the decision was taken to install two AIRCON H filters in series. This offers more flexibility during the treatment of the air flows and ensured an attained efficiency of more than 99.9%, which is sufficient to achieve the required values. This was also absolutely essential because the site was close to a residential area, which meant there was zero tolerance for odours and contamination.

AIRCON H was shown to be the right solution because the system can be easily installed without foundations. The series set-up has now been in use for approximately a year, functions optimally and handles a flow rate of 18,000 m³/h.

At DESOTEC’s facilities, all used carbon is analysed so the right measures can be taken for handling and removing the saturated carbon out of the mobile filters. All molecules that were adsorbed on the activated carbon at the customers’ site, are desorbed inside DESOTEC’s reactivation furnaces. These contaminants are then fully destroyed, in accordance with National and European legislation, by an incineration and neutralisation setup. The entire installation and it's emissions are under continuous on-line monitoring, which guarantees that only harmless water vapour is seen exiting the chimney.