There's a new weapon in the battle against landfill overflow. Weidner Ibérica, the Spanish subsidiary of the German firm Weidner, found a solution for some of the toughest materials to recycle: used electrical cables coated with flexible PVC.
The key? Just float it.
''The R-PVC we use is the 'heavy fraction' of the plastic cable waste, separated from the “light fraction” just by floating it in water,'' says Laura Lapuente, Weidner Iberica's director. ''It's as easy as that!''
The challenge was to develop a technology that allows processing PVC with a significant content of impurities from waste which was commonly landfilled. In the manufacturing, Weidner teamed up with Spain's Zicla to design injection nozzles so that recycled PVC, which often includes metal parts mixed with a small amount of other materials, could be injected into oversized pieces, larger than those they were used to..
The second improvement, more important from an economic and production standpoint, is the adaptation of the cooling systems of the injection mould. Due to more than 10 kilos of material being injected, the initial cooling process tested would have increased the price of the piece so that, as often happens, recycling would have been more expensive than using raw materials.
''Thanks to the adaptation and improvements of our machines we have been able to use recycled PVC, with almost no previous treatment or processing,'' Lapuente says.
Today, particularly in street furniture and road safety products, the most widely used material is R-PVC cable: first, because it is available in large quantities but also very importantly, due to its optimal performance for outdoor applications.
PVC cannot be corroded, it requires almost no maintenance, and protects metal parts when is used as a covering. It is lightweight, versatile and it does not degrade.
Weidner is now in the hunt for disposed of PVC cables to continue feeding its voracious machinery. ''We're already contacting companies across Spain,'' says Lapuente.
Considering used PVC cable was usually thrown away, it should not be difficult to find more of this under-looked treasure.
