Sustainability Evaluation of Pyrolysis of Waste Mattresses: A Comparison with Alternative End-of-Life Treatments

Abstract

There is a major push by governments and value chain partners to move towards circular options for difficult-to-recycle post-consumer products such as waste mattresses.[1] In the Netherlands alone ~1.5 million mattresses are discarded yearly, of which majority (>60%) is incinerated.[2] A sustainable solution to recycle waste mattresses is required to enable the Dutch industry meet the circular economy goals set by the Dutch government.[3] This paper shares major findings from the screening level life cycle assessment (LCA) of four End-of-Life (EoL) options for post-consumer mattresses: landfill, incineration with energy recovery, pyrolysis and mechanical recycling using powdering. The LCA was an important work package of a technology development project with the objective to quantify potential sustainability benefits of the pyrolysis of waste mattresses.[4] The emphasis of the pyrolysis process is on product recovery as chemical feedstock. The study showed that pyrolysis is a better option than incineration in terms of greenhouse gases (GHG) and cumulative energy demand (CED) for all the studied cases. Base case analysis showed that pyrolysis of waste mattresses can save approximately 526 kg CO2-eq. and approximately 5.1 GJ (24% savings) CED per ton waste mattresses compared to incineration. Finally, the study concluded that mechanical recycling can either be better or worse than pyrolysis depending on the processes and quality of recycled material.