Protecting health and removing odours in remediation work

With brownfield sites increasingly favoured over greenfield for construction projects, land remediation is more crucial than ever. The excavation of soil may release air emissions that require treatment on health, environmental and odour grounds. DESOTEC’s sustainable mobile filtration solutions are playing an essential role in controlling these emissions at construction sites across Europe, including at this project in France.

The problem

This remediation company was commissioned to remediate the soil at a former industrial site in France that is located next to a residential area.

Soil analysis determined that it contained trichloroethylene (TCE): a product formerly used by dry cleaners to remove stains from carpets and clothing. Before TCE’s hazardous properties became known, it was regularly used as an anaesthetic gas as well.

During the remediation work, the company installed a tent over the soil excavation site. To protect workers inside the tent, avoid causing an odour nuisance for those living nearby, and keep air quality high, there was a zero-tolerance approach to emissions. The concentration of TCE was more than 2 000 ppm, and needed to be reduced to below 2 ppm for the work to continue.

The solution

Remediation companies are always eager to surround themselves with specialist partners when a quick solution is needed. This company had already worked with DESOTEC on air and water treatment projects in the past, and approached us again for support.

After a thorough analysis, we recommended the installation of two Aircon H mobile activated carbon filters in series to handle a flow rate of 18 000 m³/ h.

This set-up offered greater flexibility during the treatment of the air flows. It also ensured a reduction in TCE of more than 99.9% - sufficient to meet the required limits.

The results

DESOTEC’s Aircon H filters have been in use for over a year and continue to function optimally, protecting the health of workers, and minimising disruption for neighbours.

Our mobile filtration solutions are ideal for remediation projects. They have a small footprint and do not require special foundations, making them easy to install at busy construction sites.

Filtration set-ups are modular, capable of flexing in line with changing requirements. They are supplied on a rental basis, so may be simply removed when remediation work is complete.

As our filters are modular, they may be installed rapidly if contamination is discovered unexpectedly during building work. This helps ensure that complex construction projects continue on schedule.

Furthermore, safe and sustainable filtration waste handling is included in DESOTEC’s full-service solution. When carbon is saturated, filters are exchanged in a swift and simple process. The old filters are transported to DESOTEC’s facilities, where carbon samples are analysed. Adsorbed molecules are destroyed in our furnaces, which are under continuous online monitoring to ensure that only harmless water vapour exits the chimney. Wherever possible, carbon is reactivated. This circular model keeps costs down, and contributes to a greener construction sector.