1. Selection of PET bottles.
2. Separation from other plastics.
3. Color sorting.
4. Crushing into flakes.
5. Washing and label removal.
6. Density-based separation.
7. Drying the flakes.
8. Sorting clear flakes.
9. Melting into strands and cutting into pellets.
10. Heating the pellets.
11. Producing polyester acoustic fiber.