In the two-year Re:Suede project, sports brand Puma has demonstrated that it can successfully turn an experimental version of its classic Suede sports shoe into compost under specific industrial conditions.

In 2021, Puma created 500 pairs of new Re:Suede shoes tanned with Zeology – a tanning agent  that is free of chrome, heavy metals and aldehyde – along with a TPE outer sole and hemp fibres.

The Re:Suede shoes were worn for half a year by volunteers in Germany to test their comfort and durability before Puma sent them to a specially equipped industrial composting area operated by its partner Ortessa Group in the Netherlands.

A special procedure had to be established to turn the shoes into compost. They were firstly shredded and mixed with other green household waste and placed into a composting tunnel and then sprayed with leaching-water from earlier composting. This contained nutrients and was naturally heated due to the biological activity and controlled air circulation in the tunnel. After approximately three and a half months, the materials that were below 10mm – small enough to pass through a sieve – were sold as Grade A compost for agricultural use, while the remaining materials were returned to the composting tunnel until they too had further broken down to the desired level. Ortessa Group adhered to all legal requirements for compost applicable at its facilities in the Netherlands during this process.

“While the Re:Suede shoes could not be processed under the standard operating procedures for industrial composting, they did eventually turn into compost,” said Anne-Laure Descours, chief sourcing officer at Puma. “We will continue to work with our partners to determine the infrastructure and technologies needed to make the process viable for a commercial version of the Re:Suede shoe, including a takeback scheme, in 2024.”

Puma will also share its insights in a detailed report, enabling peers and other interested stakeholders to learn from the experiment and apply the learnings to their own initiatives.

“We learned a lot during the Re:Suede trial about how to streamline our industrial composting process to include items that need longer to turn into compost,” said Marthien van Eersel, manager of materials and innovations at Ortessa. “While all Re:Suede materials can decompose, the soles required more pre-processing and additional time in the composting tunnel to completely break down.”

As a result of the feedback received from those who wore the Re:Suede shoes for six months, Puma will improve the comfort of future versions by enhancing the overall fit using a new material pattern for the upper and the sock liner.

www.Foreverbetter.com

www.ortessa.com