RECYCLING, A FOUR-STAGE PROCESS

The plastic material obtained from selective waste collection is taken to sorting centres.

The first step is to remove irrelevant plastic items, such as large objects, anything that is either not made of plastic or made of non-recyclable plastic. Certain obvious items (bags, pipes, chairs, sunshades) are removed before entering the facilities.

Then the articles enter a conveyor belt, where they are checked again and any foreign body is removed. Only certain products are sent to the landfill site, while others, such as fruit crates, are recovered in each type of plastic.

After the unsuitable objects have been removed, the material is sorted by size, getting rid of the smallest and lightest pieces first. A rotary screen removes small pieces and separates types of bottles (water, soft drink, detergent bottles, etc.). A second screening machine separates flat elements (films) and those with hollow parts (bottles, cans).

This stage mainly recovers a mixture of films.

The material from which small, light particles and films have been removed reaches a third stage, where the PET is separated from metals and other bottles. Metals are extracted from the flow of materials by means of a magnet and an eddy current conveyor belt for non-ferrous metals (aluminium). An optical sensor separates PET bottles from the others. The purpose of this stage is to recover metals (iron and aluminium), high-density polyethylene (HDPE) and low-density polyethylene (LDPE).