By Luis Guijarro
It is already a ritual. You put it in the yellow bag, with the rest of the plastic containers, bricks, cans or what is the same, with the other bottles of milk, juice, water and soft drinks; with bottles of shampoo, gel, detergent and fabric softener. Right next to the bag that has the paper and cardboard. One will end up in the yellow container and the other in the blue one.
This gesture of collaboration and commitment to the environment is possible thanks to the fact that Spain has distributed 566,957 recycling containers. Of these, 366,339 are yellow and are destined for the recycling of plastic containers, cans and bricks; the other 200,618 blue ones are for paper and cardboard packaging.
Thanks to people like you and gestures like this one, in 2015 more than 1.3 million tons of light packaging (yellow container) and cardboard and paper containers (blue container) were recycled throughout the national territory, reaching a recycling rate 74.8%. This percentage places Spain among the first countries in Europe in this matter, exceeding the recycling targets set by the European Union by more than 19 points (55%).
After taking them to the container, the containers are no longer at home, but what happens next? Well, the city council of each locality, with the appropriate trucks, collects the light packaging deposited in the yellow and blue containers and there begins its journey to a new life.
1. Light packaging selection plant The first stop of the bottle is the light packaging selection plant. It is a facility specialized in the manual and / or mechanical classification of the different types of light packaging, from the selective collection carried out by citizens. In Spain there are 95 sorting plants (53 of them automatic), where light packaging is separated into at least three fractions: metals (steel and aluminum), plastics (PET, HDPE, Film and Mixed Plastic) and bricks. An example of PET plastic is the water bottle, metal is a can of preserves and plastic mix, a bag of potato chips.
2. Download. For this, trucks have to go through the scale. Upon entry and exit, its origin, registration, type of load and weight of the material are recorded. The waste is deposited in the discharge plant for homogenization. In large capacity plants the material is stored in pits for subsequent feeding by octopuses.
3. Primary feeder. The material is unloaded by the loader or grapple into the primary feeder, some conveyor belts, in charge of feeding and dosing the treatment line. In a first manual review, the most visible improprieties are removed. Even today there are many citizens who get confused and deposit, especially in the yellow container, improper waste that spoils everyone's effort. According to Ecoembes, although there has been a positive evolution regarding the deposit of improper, these are between 25 and 30%.
4. The bag openers. The bag openers open and empty the bags, homogenizing the flow that reaches the trommel (screening machine), which, as if it were a large centrifuge, performs a rotating sieve by dropping the bags and loose containers through its holes, separating them from the larger ones.
5. The ballistic separator. With an oscillatory movement, this system filters and classifies by densities, forming three groups: planar (flatter containers), rolling and fine.
6. Five different separations The latest technology now helps to separate everything by materials. In pneumatic separation, the film material must be aspirated to facilitate the selection of the rest of the materials. This is followed by a large magnet that performs the magnetic separation, which selects the steel containers. Through optical separation, image sensors analyze waste in milliseconds selecting materials from PET, HDPE, CBA (cardboard containers for beverages and food, bricks) and other plastic containers that are propelled into different conduits by jets of air.
The time has come for separation by induction, a separator that removes the aluminum material, taking advantage of its behavior in the face of eddy currents. By opposing magnetic fields, the ferrous metals are separated from the non-ferrous ones, which are repelled and leave the tape from the rest of the materials. A final manual separation appears on the scene, because although the automated separation system is very precise, a quality control is carried out on all the previously selected containers, in case something improper has been cast.
7. To the silo. After phase six, the containers are separated in their corresponding silo. Reject material from the facility is sent to landfill or transformed into fuel by an external manager. The rest of the materials are led to a press to form the bales of the different materials.
8. Pressing. Plastics and CBA are pressed in the multimaterial press. The metals are pressed apart in a space according to their characteristics.
9. Transportation. The multi-colored bales are loaded into trailers that will transport them to different recycling companies.
10. A new life. Our milk bottle has undergone a transformation process. Now he is traveling to his corresponding recycler who can transform 40 PET bottles into a fleece lining and 80 soda cans into a bicycle tire.