The second life of plastic
Do you know what happens to your plastic waste?
Most of it is recycled so that the waste has a new life. The rest is simply reused after reconditioning.
Rigid plastics
Plastic lends itself quite well to recycling, provided that the different types are sorted correctly (HDPE, PVC, PET, etc.). These types must be recycled separately in order to obtain an impeccable end product.
The plastic is first sorted to separate the different polymers from each other. This is usually done manually on a conveyor belt. Each load of plastic is washed and crushed.
The crushed plastic is then sorted again by means of flotation. Thanks to this method, the polymers can be separated depending on their density: heavy polymers sink, light polymers keep floating on the surface.
The polymers are also sorted by colour thanks to an optical NIR sensor (NearInfrared).
The last stage differs on a case-by-case basis:
- Either the polymers are melted and extruded (injection moulding): they are pushed out through a tube by a screw and come out homogeneously in the form of a “sausage”. These “sausages” are then cut to make granules.
- Or the polymers are ground into agglomerates.
These granulates and agglomerates are then used in new production processes.
In other cases, recycling companies make their own products and no intermediate extrusion is required.
Nothing is lost, everything is reused
Granulates and agglomerates resulting from recycling can then serve as raw materials for the production of new plastics. Polymers retain their properties and can therefore be reused.
This form of recycling is profitable if the source is properly sorted. A high-quality product is only obtained if the granulate and the agglomerate of the polymers are sufficiently pure and homogeneous.
Plastic drums and IBC
Plastic drums and IBCs (1000-litre drums on a pallet in a metal frame) are very often reusable after “reconditioning”.
Plastic drums and IBCs are reconditioned in various stages:
- The processor starts by removing stoppers, taps and lids. The IBC drums are detached from the pallet and the cage.
- Afterwards, the drums are checked and if necessary, repaired. The drums which cannot be repaired are recycled or valorised for energy recovery.
- The drums and containers are then cleaned (in an automated manner or manually). After this stage, the inside of the drum is completely clean and there are no labels adhering to the outside anymore.
- After a leak test, the drums are ready for reconditioning.
Reconditioning
- Once the drums have been treated, cleaned and refurbished, they are repainted both on the inside and the outside.
- Tight-head drums are closed with a stopper.
- Open drums are closed with a lid and ring.
Many reconditionable drums are returnable and taken back by the suppliers of the products they once contained. The cost of reconditioning is much lower than the cost of producing a new container.
Isomo (EPS)
Styrofoam or expanded polystyrene can be recycled very easily. You are most likely surrounded by styrofoam in your daily life …
Styrofoam blocks (EPS) are first collected by recycling parks or specialised companies.
The blocks are initially sorted and cleaned of all dirt. Then they are crushed without destroying the beads from which they are made. Then they undergo a transformation process that differs depending on the final use.
Different reuses of styrofoam
New combined with old: insulating tiles and packaging
White, clean and dry expanded polystyrene is crushed without destroying the beads from which it is made.
These beads will be reused to make new packaging or insulating sheets and tiles.
A new life: from styrofoam to rigid plastic
Styrofoam can also be extruded to obtain a polystyrene granulate that can serve as a raw material in the plastic industry, to manufacture CD cases, coat hangers, street furniture, etc.
Styrofoam as a raw material for insulating mortar
The beads remaining from the first transformation are mixed with cement, excipients and vermiculite (insulating material). That mixture is then packed in bags and marketed. Subsequently, the contents of the bag just needs to be mixed with water. This creates a mortar which can be pumped and spread out for a uniform coating/subfloor:
- Insulation of floors: this material provides good thermal insulation and excellent mechanical resistance.
- Insulation of flat roofs: creates excellent thermal insulation in combination with polystyrene (EPS) or polyurethane (PUR).