Polypropylene recovery of post- industrial carpet In association with Carpet Recycling UK Funded by Envirolink Northwest Andy Mail

Summary Project aims Method of recovery Trial results Project conclusions Next steps

Project aim 10,000 tpa of post- industrial carpet enters UK waste stream. Approx 50% is PP. Can this carpet be recycled on a commercial scale?

Two research tasks Post-consumer - identification and preparation for extrusion Post-industrial – bulk feeding and extrusion

Post-consumer identification

Size reduction and screening of post-consumer carpet Granulator sizes; 10, 15 and 20mm Screen sizes; 2, 4, 5.6, 8 and 11.2mm 80% yield when granulate at 20mm and screen at 2mm Work is currently ongoing Next stages include aggressive screening and air classification

Post-industrial recovery Baled post-industrial carpet 1.2m x 0.5m strips Tufted, PP with small contamination of PET ShreddingFeed extruderExtrusion

Size reduction and feeding the extruder 4 shaft shredder used with 25mm screen Approximately 150 kg/h Small particle size = easier to extrude Material ‘fluffs-up’ once shredded Caused bridging inside the feed hopper of extruder

Solutions 1.Increased shredder screen size 2.Compact material before extrusion within hopper 3.Pelletising mills Increased operating costs

Extrusion Extruded material was weak when transferring to pelletiser Possible cause: Blowing within the extruder Vacuum extraction should improve this

Trial results Physical properties test Units Post industrial carpet Virgin PP used for injection moulding MFI (at 230°C, 2.16kg) Tensile strengthMPa1732 Impact strengthkJ/m Yield%7.310 Break%15 Densityg/cm Ash%170

Trial results Few surface defects Physical properties match lab scale trial

Trial conclusions and next steps Successful recovery of PP at large scale Closely matches lab scale results Potential feedstock for injection moulding Next steps: Compact material in feed hopper Pelletise fibre prior to extrusion Vacuum extraction during extrusion

Axion Consulting Tudor House Meadway Bramhall SK2 2DG