PET bottle recycling

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 into landfills. 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: chemical recycling and mechanical recycling.

Mechanical recycling

High contamination levels by other materials causes great deterioration of post-consumer 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 minimizes the moisture content of the PET flakes. Drying reduces the hydrolytic degradation effect and leads to higher R-PET melt strength.

Bottle-to-bottle-recycling

PET bottle-to-bottle recycling leads to high decontamination levels of the recycled PET bottles. Technologies in this market segment have been designed to process and produce PET for re-use in food-grade bottle production

PET Recycling Associations

Many trade and non-profit associations worldwide dedicate their work to the subject of PET recycling.