PET bottle recycling: Difference between revisions

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== PET bottle recycling ==

[[PET (Polyethylenterephthalate)]] bottles can be recycled to reuse the material out of which they are made and to reduce the amount of waste going intolandfills. PET is semiporous and absorbs molecules of the food or beverage contained, and the residue is difficult to remove. Using PET bottle flakes to successfully produce higher value products needs improved flake production methods, suitable quality control tools, suitable conversion processes and the right processing equipment. Unlike virgin material, the processing of bottle flakes to the different intermediates and final products needs specific attention, depending on the process or final products that are selected.

In oder to recycle post-consumer PET bottles, two major processes have been applied: chemi-

cal recycling and mechanical recycling.

=== Mechanical recycling ===

High contamination levels by other materials causes great deterioration of POSTC-PET during processing. Mechanical recycling of post-consumer-PET consists of contamination removal by sorting and washing, drying and melt processing.

==== Sorting and washing ====

Contaminant removal in this step consists of several processes in which POSTC-PET bottles are sorted, ground and washed. PET bottles are separated from PVC, polyethylene and other plastic containers. PVC can be removed manually from PET bottle scrap before the grinding process. While no 100% separation of PVC is reported yet, efficient separation of PVC from mixed PVC/PET bottles scrap can be achieved using methods based on the difference between the physical or chemical properties of PVC and PET. After sorting, post-consumer PEt is ground into flakes. PET flakes are washed following grinding.

==== Drying ====

Drying is minimizing the moisture content of the PET flakes and hence reduces the hydrolytic degradation

effect and leads to higher R-PET melt strength.

=== Bottle-to-bottle-recycling ===