From idea to innovation

PIR insulation boards are commonly used in walls, floors and roofs. Unilin has been able to mechanically recycle these boards for some time, using them in products like our Rezillo construction panels, but genuinely circular material use takes more: separating and reusing the two main components of PIR – polyol and MDI. That is exactly what Unilin Insulation set out to achieve, with a process that is now fully operational.

Three steps

"When I joined Unilin Insulation three and a half years ago, I got started on the initial studies almost immediately,” explains R&D engineer Arno Verlee. He developed the recycling process in three steps:

1. Grinding
2. Filtering
3. Chemical recycling

“That final stage uses glycolysis, which breaks the chemical bonds in the foam. It’s a known principle but it had to be fully tailored to our materials and processes. In the lab, things fell into place rather quickly but the real challenges hit when we started to scale up.”

Testing and adjustment

The first large-scale tests went far from smoothly. Mixing, dosing and filtering caused issues as the installation kept getting clogged. “We hit plenty of snags but we were always able to identify the cause and adjust the system,” says Thomas.

Turning point: innovation at the heart of the process

The major breakthrough came with a new mixing installation that was better suited to the new process. “That was the turning point when everything fell into place,” says Arno. “Even better, it happened within a respectable production time,” Thomas adds. Today the process is technically sound and that’s a first in the industry for Unilin.

A second life thanks to Recover

Moreover, the recycling process is also scalable and reliable. Initially, the installation processes production scrap from our own site in Desselgem but we have higher ambitions. Through the Unilin Recover programme, a take-back model is being actively developed to collect PIR waste from construction sites. This post-industrial waste is essential to feed the installation on a larger scale. Meanwhile, the team continues to place maximum emphasis on optimisation. “We want to increase the share of recycled polyol in the new insulation boards without compromising on quality. We’re currently exploring whether 100% is possible”, says Arno. Unilin is also participating in projects exploring how MDI – the other component of PIR, next to polyol – can be recycled. “The more we can recycle, the more sustainable, and the better for our planet,” Thomas concludes.

Discover more about sustainability at Unilin