The aim of the pre-treatment – for waste from both the organic and refuse containers – is to sort waste in four kinds of materials:
- Organic matter: it goes on to the biological treatment area, where the organic sorted at collection and the one coming from the refuse stream are also kept apart.
- Recyclable materials and bulky waste: are sorted according to materials, crushed and sent to recycling plants.
- Pre-solid recovered fuel: a mixture of non-recyclable plastics and paper or cardboard that is prepared to be used as alternative fuel in several industries; before using it as fuel, it'll have to be shredded into smaller fragments.
- Residue: the material that can't be used – the residue from the plant – is baled up or compacted to take it to Can Mata landfill.