C. How is the recycling process itself working? (Mechanical Recycling)

(HD)PE and PP – in different streams, but the process is the same:

• Shredding: the material into small pieces
• Washing: a bath with circulating water (ca. 40°C) removes most residuals, labels and adhesives
• Separation by density: Different plastics are separated by different density, so one is sinking and the other is floating. PE and PP have a density < 1 g/cm3, so it’s floating in water. The floating plastic will be separated.
  Density ranges may overlap (PE & PP), that makes it challenging to guarantee a material purity.
• Granulates: Flakes are further processed (melted) into granulates, that’s the recyclate.

PET clear, after sorting out any coloured or opaque PET:

• Shredding: the material into small pieces
• Washing: a bath with circulating water (ca. 40°C) removes most residuals, labels and adhesives
• Separation by density: Different plastics are separated by different density, so one is sinking and the other is floating. PET and PS have a density > 1 g/cm3, so it’s sinking. PE and PP have a density < 1 g/cm3, so it’s floating in water. The sank plastic is separated.
• Alkali hot-washing: Washing with alkali surfactants and water (ca. 85°C)
• Drying & sorting: the flakes will be sorted again by colour
• Granulates: Flakes are further processed (melted) into granulates, that’s the clear recyclate.