Germany – A collaboration between BASF, KrausMaffei, Rampf and Remondis is looking at how the rigid polyurethane insulation from end-of-life refrigeration can be used to make new materials.
Once an old refrigerator has been disposed as prescribed in the EU directive on waste electrical and electronic equipment (WEEE), the rigid PU foam insulation ends up as regrind. Until now, this has typically been used for energy purposes rather than remaining in the material chain. This typically only recovers about 30% of the energy that was used to produce it.
The four partners in the collaboration will be using a depolymerisation process to regenerate a polyol. This recycled polyol can then be used to make new polyurethane materials, closing the material cycle.
Previously, such chemical recycling processes for PU have largely focused on post-industrial waste, where the waste stream is typically homogeneous, making recycling easier. Post-consumer waste, as is the case with the rigid foam from old refrigerators, is far more difficult, being heavily with other plastics and metals. Initial trials have been promising.
BASF Polyrethanes in Lemförde is responsible for the chemical testing and qualitative evaluation of the recycled material. ‘The chemical recycling process of PUR waste from refrigerator recycling that will be developed during this collaboration must be economically and ecologically sustainable, while also meeting BASF’s high product quality requirements,’ said Joerg Krogmann, who works in chemical development for the company.
Remondis Electrorecycling, based in Lünen, Germany, is working at the start of the process, ‘We are the first step in the sustainable supply of raw materials,’ said Remondis sales manager Sebastian Schormann. ‘A basic prerequisite for an innovative waste equipment recycling route is that the waste management industry makes the appropriate waste material available to the other players in the recycling chain according to the correct specifications and in industrial quantities.’
Pirmansens-based Rampf is contributing its skills in the chemical recycling of PU to the project. ‘We want to establish innovative process technologies that are better able to deal with increased levels of foreign substances in post-consumer materials,’ said Rampf plant manager Michael Kugler.
Machinery manufacturer KraussMaffei, meanwhile, is developing the technology required for the plant engineering. ‘Together with our partners, we want to advance technologies for the chemical recycling of polyurethane materials in this project,’ said Munich-based trend scouting manager at KraussMaffei Technologies. ‘Recycling plastics has a great future – and it requires the right technologies and machines.’