For over a century, Differdange has lived to the rhythm of its steelworks, from the historic Hauts-Fourneaux et Aciéries de Differdange (HADIR) to the modern-day ArcelorMittal. For decades, red flames and black dust dominated the landscape. New investments, however, are poised to significantly clean the air breathed by local residents.
As part of a broader effort to make its production more environmentally friendly, the ArcelorMittal group is investing in a major new dust extraction system at its Differdange site.
The system uses imposing pipes to extract 1.2 million cubic metres of air per hour from the plant. This air is then filtered in a large, repurposed unit that was previously used in Florange, France, until its closure in 2013. Over the past two years, the unit has been refurbished, expanded, and transferred to Differdange.
Project manager Cleison Webber explained the filtration process. “There are more than 4,600 filter bags”, he stated, likening them to seven-metre-long socks that collect dust on their outer surface. Periodically, an automatic cleaning cycle – referred to as “bag shaking” – causes the accumulated dust to fall into collection hoppers. Once fully operational, the system will have a capacity to filter one tonne of dust per day.
The installation targets specific areas within the steelworks identified as major dust sources during production. One key location is an oversized chamber where large containers from the steel furnace are cleaned.
Pierre Collin, production manager at the Differdange steelworks, explained the challenge: “These operations are generally carried out with oxygen lances and generate a large amount of dust, intensely but for a short period.” He detailed the solution: “The aim of the project was therefore to try to contain this space as much as possible and place it under negative pressure. We extract the air from this box and thus capture all the dust emitted during this operation.”
A few metres away, a large flue has been installed above one of the furnaces. In a subsequent phase, the fumes and dust generated during the rolling of steel beams will also be channelled into this system.
Pierre Jacobs, CEO of ArcelorMittal Long Products Luxembourg, summarised the project’s scope: “This is a €23 million project to capture, that is, to extract, 85% of all dust produced here at the Differdange site.”
The expected result is a major reduction in emissions. The investment is designed to significantly reduce dust exposure for the plant’s own workers and should also improve the quality of life for residents in the immediate vicinity of the steelworks.
The project is not yet standard in Europe and has received public backing, with the Luxembourg state contributing €6 million to the new facility.
