Getting from a used bottle on a kitchen counter to a new one on a supermarket shelf involves a carefully orchestrated sequence of steps, each of which determines the quality of the final recycled material.

What is PET plastic and why is it so common?

PET (polyethylene terephthalate) is the plastic behind most water and soft drink bottles, and it is also one of the success stories of modern recycling. Lightweight, transparent and chemically stable, PET can be recycled multiple times into new bottles, textile fibres, strapping and a wide range of other products – which is exactly why it has become the default choice for beverage packaging worldwide.

How is PET plastic recycled?

The journey begins with collection, whether through kerbside recycling schemes, deposit return systems or commercial collection from businesses. PET bottles arrive at a recycling facility mixed with other plastics, packaging and contaminants – caps made of a different polymer, labels, residual liquids and sometimes other materials entirely that have been incorrectly placed in recycling bins.

The first major processing stage is sorting. This is where the material stream is separated by polymer type, colour and form. Optical sorting systems using near-infrared sensors scan the incoming material at high speed, identifying PET bottles and separating them from HDPE, polypropylene, films and other plastics, while also distinguishing between clear and coloured PET – an important distinction, since clear PET commands the highest value and is suitable for "bottle-to-bottle" recycling, while coloured PET is often directed to other applications such as fibre production.

Once sorted, PET bottles are typically baled and sent to a reprocessing facility, where they go through shredding into small flakes, followed by washing to remove labels, adhesives, dirt and any remaining liquid residues. A further separation step, often using flotation tanks, removes caps and label fragments made of polypropylene or polyethylene, which are less dense than PET and float to the surface, while clean PET flakes sink and are collected.

What can recycled PET become?

The resulting clean PET flake, often called rPET, can then be melted and extruded into new pellets, which manufacturers use to produce new bottles, food-grade packaging (subject to additional decontamination steps), polyester fibres for textiles and carpets, or other plastic products.

Challenges of PET recycling and future tech innovations

The purity of the rPET flake is critical: even small amounts of contamination from PVC, other polymers or coloured material can affect the clarity, colour and mechanical properties of the final recycled product, limiting the applications it can be used for. This is why the sorting stage at the very beginning of the process has such an outsized influence on the value of the entire chain. PICVISA's ECOPACK and ECOFLAKE systems are designed to deliver exactly this kind of high-purity separation – identifying PET by polymer type and colour, removing PVC and other contaminants, and producing the clean, well-characterised input streams that reprocessors need to manufacture high-quality rPET.

Tips for recycling PET plastics

At home, the most useful steps are simple: rinse bottles to remove residue, leave caps on (modern sorting systems are designed to separate them automatically), and avoid crushing bottles flat where possible, since shape can help optical sorters recognise them. By improving sorting accuracy at the front end, the entire PET recycling chain becomes more efficient, supporting a genuinely circular life cycle for one of the world's most widely used plastics.

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