Until a few years ago, reports suggested there was no effective solution to the problem of discarded mattresses: 60% ended up in landfills, and the remaining 40% were incinerated. Today, solutions are closer than expected.

The scenario proposed by PUReSmart is revolutionising traditional integrated systems of mattress production and recycling, moving from a conventional model to a more favourable style in terms of efficiency and material recovery.

Four years ago, the PUReSmart consortium set out to find ways to transition from the linear life cycle of polyurethane (PU) products to a circular economy model. PUReSmart suggested an optimal scenario from the outset; proper polyurethane recycling would have to start with a solid mechanical sorting process in favour of chemolysis.

At present, the results speak for themselves. Redwave now offers the first NIR sensor-based sorting solution to reuse flexible polyurethane foam. Near-infrared reflectance spectroscopy has proven to be a powerful tool for sorting of numerous thermoplastics (PET, PE…) and, for the first time in the industry’s history, it is being used to sort PU foams.

Redwave’s research and development team has developed a reliable solution for PU waste sorting, containing all necessary units for sorting flexible foam. Currently, the Redwave sorting machine can identify and sort between 20-30 different types of PU, such as MDI-based foam, Conventional foam and HR-based foam, as well as foams containing certain additives like flame-retardants.

The ongoing technological scope focuses on advanced sorting of EoL PU-based materials to recover the major PU building blocks – polyols and isocyanates – in the downstream chemical processes.

An innovative process for the chemolysis of end-of-life polyurethane is close to becoming a reality, as the development of an advanced recycling system takes priority in the PUReSmart project: the aim is to find a new PU-based chemistry that allows full recyclability of the material. Two technological approaches are integrated to achieve the result: Smart mechanical recycling and the chemolysis developed in PUReSmart.

By involving the chemical industry, it is possible to develop carbon-neutral production models, thus aligning both the ambitions of the plastics sector and its environmental objectives. In recent months, Recticel Engineered Foams, a member company of the PUReSmart consortium, has conducted various trials and experiments for valorising the upper phase and lower phase by polyurethane (PU) foaming based on recycled polyols and isocyanates obtained from Covestro’s pilot plant.

Source: Recycling Magazine