Best practices for ecodesign in anticipation of the end of life of flat screens

Limit the variety of resins used, preferring largely recycled resins such as PP, ABS, PS, PMMA
(for the module display), and to a lesser extent,
ABS/PC and PC.

In the WEEE sector, some resins are easier to recycle because:

• Appropriate recycling operational technologies are available to produce new resins (e.g. thermoplastic vs. thermoset resins).
• They have specific technical features (including their density) enabling their identification, and thereby their efficient sorting.
• They are present in large quantities making their recycling efficient from a technical and economic point of view.

Limiting the variety of resins used while focusing on the resins mentioned opposite thus leads to an increase in the equipment recycling rate.
It should be noted that PMMA is the main plastic used in display modules, which go through a specific treatment stage. It can thus be recycled. However, it is more difficult to recycle PMMA when used for other parts of a screen.

Whenever possible, avoid using the materials
listed below, as they are hardly recycled as part
of the treatment process of flat screens:

• wood,
• composite materials,
• mineral materials,
• bio-sourced material.

Some materials are not commonly used in flat screens. Thus, following the different treatment stages, these parts that are present in small quantities, are not specifically detected by the sorting techniques. These remaining fractions are not recycled but only recovered to produce energy in certain cases, or even disposed of (by incineration or secure landfilling).

Preferably use single-material components rather than composite materials whenever possible.

Multi-material components (e.g. composite materials, bi-injected or co-extruded plastics...) cannot be totally separated during grinding processes. They will thus be turned into fragments made up of several materials at the end of the process.
These fragments disturb the sorting processes and/or affect the performance of downstream sectors of recycling for each of these fractions.

Promote the use of plastics dyed in the mass instead of surface coatings, and limit surface treatments on plastic components whenever possible.

Coatings and surface treatments (paint, metallisation...) generate sorting errors when materials are separated using optical sorting technologies. Plastic fragments may thus be considered as non-recyclable because the optical technology will only analyse the material surface, rather than the plastic resin itself.
If these plastic fragments are nonetheless directed to the relevant downstream sector of recycling, these coatings/treatments may limit the performance of plastic regeneration plants and/or affect the properties of recycled plastics.

Avoid the use of non-ferrous metal treatments or coatings on ferrous metal components.

Using non-ferrous surface treatments on ferrous metal components (e.g. copper coating on a steel component) disturbs detection operations, and thus magnetic metal separation. These parts may not be directed to the relevant downstream sector of recycling.

In the absence of regulatory requirements relating to product safety, avoid incorporating flame retardants into plastic components. If these requirements involve the use of flame retardants on some components, prefer non brominated flame retardants.

Some brominated additives, that were once authorised, are now prohibited in new products. In order to ensure plastics from recycled flat screens do not contain these additives, they go through complex sorting. All plastics considered as containing “bromine” are thus isolated and disposed of in a hazardous waste incineration unit.
The technologies currently available cannot distinguish prohibited brominated additives from other authorised additives (containing bromine or not). This oversorting process thus results in the loss of plastic material to be recycled.
It is therefore important to limit, as far as possible, the use of brominated flame retardants, and more broadly, the use of flame retardants, whenever the regulatory requirements relating to product safety allow it.

Avoid incorporating fillers (mineral or vegetal) into plastics whenever possible.

The presence of fillers in plastics alters the density of resins, and thus disturbs the systems sorting plastics by resin family in preparation for their regeneration.

Preferably place cells and batteries so they are readily accessible without dismantling the product, using for example, a hatch, a snap-fit cover...

Cells and batteries must be removed from the early treatment stages in order to be directed to specific treatment sectors, and before contaminating the other fractions. These parts are hard to identify and sort after the grinding stage. Operators must therefore remove them easily during the hand decontamination stage, prior to grinding.

Avoid welding cells directly on circuit boards.

The cells that are directly welded on circuit boards are hardly identified by sorting operators and may be end up in the circuit board fraction. Therefore, they will not go through any treatment process specific to cells and batteries.

Whenever possible, indicate the presence of lithium-based cells and batteries on the product, and make the right design choices for easy removal (see recommendations above).

“Lithium” cells and batteries are very sensitive to short circuits. Their use entails a risk of explosion as operators may cause a short circuit trying to remove them during the manual sorting stages. If cells and batteries are not removed during the early manual sorting stages, explosions may take place and fires may break out near the disintegrator or the grinding machine.

For easy removal of circuit boards:

• prefer clipping to fix them on the support,
• limit the number of fixing points.

Circuit boards are components requiring a specific treatment as described in the WEEE Directive ( Directive 2012/19/EU). They must be removed from the early treatment stages in order to be directed to specific treatment sectors. Moreover, they contain critical metals whose recycling is an important challenge in environmental and economic terms and resource availability. Some assembly methods make their removal more difficult, thus reducing the recycling rate of these critical metals.