PROJECT DESCRIPTION
BACKGROUND
Tyres and automotive component applications, which represent some 75% of rubber demand at the European level, make very little or no use at all of reprocessed rubber feedstock. Reclaimed rubber from End-of-Life Tyres (ELT) and grounded rubber production waste are used at very low concentrations in tyre manufacturing (3%-5%), due to technical constraints. As a consequence, despite the increasing cost of raw materials and the environmental issues related to their consumption, the material recycling and reuse rate of rubber waste is still very low (i.e. 12.8%, decreasing to 1.5 wt% if considering the amount reused for remanufacturing high-value products like compounded General Rubber Goods - GRG - and tyres). Moreover, at the European level, GRG production waste (offcuts and defects, which amount to about 9 wt% of the overall production) is predominantly landfilled (65%) or disposed of through incineration (17.5%) with energy recovery.
OBJECTIVES
The LIFE GREEN VULCAN project aimed at increasing the reuse rate of rubber waste with an innovative and environmentally-friendly devulcanisation technology. The technology was demonstrated through the manufacturing of two compounds using a high content of reprocessed rubber feedstock from End-of-Life Tyres (ELTs): (i) a compound for manufacturing spring pads for cars and light trucks, and (ii) a compound for manufacturing Passenger Car Radial (PCR) tyre treads. The innovative technology allows an increase in the recycling rate of rubber from end-of-life vehicles, while reducing CO2 emissions linked to the production process.
The project contributed to the implementation of the EU Waste Framework Directive (2008/98/EC) by developing a recycling route for ELTs, the Waste Shipment Regulation (2006/1013/EC) by recycling ELTs into products to hinder illegal ELT shipments outside Europe, the End-of-Life Vehicles Directive (2018/849/EU) by enabling increased recycling rates, the Circular Economy Action Plan, and the 2030 Climate and Energy Framework by reducing CO2 emissions from rubber production.
RESULTS
The project successfully demonstrated an innovative technology to produce recycled devulcanised rubber from End-of-Life Tires (ELT), validating the developed product in two industrial applications linked to the automotive sectors: Spring Pads (a component of the car suspension system absorbing shocks) and Passenger Car Radial (PCR) tyres.
The technical performance of the developed recycled rubber was continuously improved, testing also the addition of nano-clay materials. Eventually, thanks to a very good selection of the ELT waste and to several improvements in the production process, the recycled rubber without nano-clay modifications reached the target performances (thus further lowering the product sustainability in environmental and economic terms). As a result, Spring Pads and PCR tires containing 20% and 10% recycled rubber, respectively, were produced, significantly surpassing the current industry standards set by STELLANTIS and BRIDGESTONE. The exceptional performance of the developed rubber led to its successful market introduction, with nearly 300 tons sold by project end to key automotive and rubber industry players, ensuring widespread adoption of the project's benefits.
Thanks to the experience gained, representatives of the project partners participated in working tables of CEN working groups and in discussions within the revision process for the ELV (End-of-Life Vehicles - 2000/53/EC) and 3R (type approval of motor vehicles with regard their reusability, recyclability and recoverability - 2005/64/EC) Directives. Moreover, the improved wear resistance properties obtainable in tyres with the project devulcanised rubber could improve durability of the tyres while reducing the particulate emitted from the tyre/road interaction, thus making the related products more in line with the non-exhaust emission requirements set by the new Euro 7 standard for motor vehicles.
