What is better for recycling: PET granules or flex
19.12.2022

PET packaging for bottling and distributing liquid foods and drinking water is becoming increasingly popular. In this regard, environmental problems are increasingly felt due to too much accumulation of plastic in nature and its negative impact on the environment. The problem can be solved by recycling – thermoplastic processing. First, PET granules or flexes are obtained from waste, and then this raw material is used for the production of goods. Recycled PET is used for the manufacture of packaging and technical films, polyester fibers, preforms and much more. Let's find out which raw materials can be used more profitably in the PET recycling process: flakes or granules.

What are flexes

The most common type of recycling of plastic bottles is the production of small pieces from them – flexes. The process does not require plasticization of PET waste. It goes through several stages:

  1. Sorting plastic from other types of plastic containers.
  2. Shipping.
  3. Washing and cleaning of labels, glue and dirt.
  4. Agglomeration.

Flexes – small pieces of plastic of different colors and shapes. In the future, they are used for the production of secondary materials and packaging or recyclable materials – granulate. Flexes are stored and transported in plastic bags weighing from 420 to 930 kg.

What is a granulate

The second method of recycling plastic bottles – this is the manufacture of PET granulate from them. This raw material is obtained by grinding and plasticizing polymeric materials. The granulate formed as a result of waste processing is small colorless or colored granules or grains no larger than 12 mm in size. Such recycled materials cost 1.5 times cheaper than primary granulate. In the future, it goes to the production of new plastic bottles, technical films, synthetic fibers.

How granules are made

For the production of granules from sorted and prepared plastic, special equipment is needed – granulator. In it, raw materials (flexes) are processed in order to rid them of moisture and internal impurities. The process looks like this:

  1. Recyclable materials enter the loading hopper, where they are separated from metal inclusions.
  2. Under the influence of high temperature and vacuum, plastic flakes get rid of moisture and impurities.
  3. In the extruder, the raw material is melted and goes through another purification stage.
  4. Next, the elements are cut into granules and crystallized.   

The output is a material in the form of grains, well cleaned and with increased viscosity characteristics.

Benefits of PET granulate

To understand which type of recyclable material is better to use for the production of goods, it is enough to compare their technical characteristics. Flexes have a number of disadvantages in comparison with PET granulate. The main ones are:

  • Poorly cleaned, which leads to third-party inclusions getting into finished products, due to which products are of poor quality . The granules go through several stages of purification and do not have this drawback.
  • Damp and clumpy. The granules are less hygroscopic and do not stick together, so the percentage of residual moisture in them is small. 
  • 3 times lighter than granules, so transporting large volumes is several times more expensive than granules.

If we compare the technical characteristics of these two types of recyclable materials, it turns out that PET granulate is a higher quality type of material. It is more suitable for recycling and making industrial products. In addition, the productivity of equipment for the production of granules is 40-60% higher than the capacity of equipment for flex.

Product range of Preform Factory

Preform Factory Company successfully sells ready-made PET containers of various sizes and preforms for plastic bottles. The key to the success of the company – use of high-quality raw materials, modern equipment and innovative developments in the field of manufacturing PET containers. The plant's product range is extremely wide: there are plastic bottles of various shapes, sizes and volumes, as well as various preforms (blanks) for blowing plastic bottles. Using the products of the company «Preform Plant» will allow you to build a profitable and successful business.