Less plastic ending up in landfill, or in energy recovery. This is the objective of the Enea (National Agency for New Technologies, Energy and Sustainable Economic Development) project that led to the development of a process capable of producing a filament to be used as toner in 3D printers. A printable polymer, derived from the plastic in electrical and electronic equipment (WEEE), with the same technical characteristics as the virgin material, at a lower cost.

Enea's project to recover plastic from WEEE

The two-year project was launched in agreement with the Ministry of the Environment and aims to find a sustainable and more profitable alternative to the polymer most commonly used as a feed filament in 3D printers, namely virgin Acrylonitrile Butadiene Styrene (ABS), which has a selling price of between 20 and 50 euros per kilogram. In Enea's laboratories, researchers have therefore produced filaments and 3D prototypes using various types of plastic recovered from collection and recycling centres for WEEE, demonstrating that these were of equal or similar quality to those made with "virgin" polymers. Enea explains that the availability of spools at a lower cost than those produced with virgin ABS represents an advantage for consumers, also in view of the continuously expanding market and the many applications of additive manufacturing, from toys to object repair, from prototypes to satellites and even the construction of residential units.

"Over the years we have often heard WEEE treatment plants and other plastic recycling operators complain that it is difficult to make a profit from the recycled plastic market," Riccardo Tuffi, a researcher in Enea's laboratory for technologies for the reuse, recycling, recovery and valorisation of waste and materials, explains to LifeGate. "Either the cost of the raw material is too low or the quality of the recycled plastic is poor. The situation worsened after China's ban on the import of such waste. We therefore felt it would be useful to provide WEEE plants with an idea and a means of valorising this fraction. Not all WEEE plastic can be used for this application, but a good proportion of it can."

A new life for plastic from WEEE

When the subject of circular economy comes up, it becomes apparent that a genuine market for secondary raw materials is still lacking. And this is not for want of technology or material, at least in most cases. It is a kind of distortion that relegates recycled materials — plastics in this case — to being sold at very low prices, to energy recovery, or in the worst case, to landfill. The goal of Enea's project is to "reduce WEEE plastic from incineration and landfill" and bring "greater profits for operators in the sector, reducing the virgin plastic used for 3D printing," Tuffi continues. "The possible uses are endless. Or rather, they are the same as those already existing for 3D printing with commercial filaments. Of course, the recycled filament is aesthetically less appealing: usually grey, white or black. However, the quality of the printed products is very similar. It could be used for rough drafts before the final 'clean' version." As the researcher explains, the amount of filament wasted during the various printing attempts is considerable.

The next step is to achieve possible industrialisation of the process, also in order to comply with the regulation requiring the recovery, in terms of both material and energy, of between 75 and 85 per cent by weight of a WEEE device sent for treatment. "It must always be borne in mind, however, that plastic cannot be recycled an infinite number of times, as it loses its properties between one extrusion and the next. So in the end there will always be energy recovery or, preferably, chemical recycling," Tuffi concludes. A way, in any case, of extending the life of a material and putting off as long as possible the moment when it will be forgotten in a landfill.