ELG’s furnace has a low oxygen content, so as Barnes describes, the company pyrolizes the non-carbon fiber materials and turns them into gas. Those gasses get burnt off in an exhaust treatment system. Later, a carbon char forms on the carbon fiber and ELG introduces air into the process that oxidizes the char into CO2. “And we end up at the end of this process with a clean carbon fiber that shows a slight reduction in tensile strength compared to virgin fiber and virtually the same tensile modulus as virgin fiber,” Barnes says. He adds ELG can produce around 1,500 tons of fiber output through that process.
One of the biggest potential markets for recycled carbon fiber is automotive. According to Recycling International magazine, about 10 percent of the CFRP used in BMW i series vehicles is recycled material. Toyota Europe adds that by European Union law, all new vehicles in Europe have to be 85 percent reusable or recyclable (by mass) and 95 percent recoverable. In Germany, landfilling is already prohibited, adding to industry’s urgency to reclaim as much carbon fiber as possible. Barnes says that recycling gives the automotive industry a stable supply chain, low cost carbon fiber (less than $5-7 per pound) as well as 90 percent less global warming impact than virgin carbon fiber.
Recycling carbon fiber could also revolutionize the way cars are made. Last year, ELG collaborated with Gordon Murray Design in the development of iStream® – the world’s first affordable high-volume carbon fiber chassis. The iStream has a hybrid structural composite chassis comprising 14 composite structural panels made from Carbiso™ M, ELG’s signature line of carbon fiber nonwoven mats. Barnes says a project of that magnitude would not have been possible without close collaboration.
“I think [you need] that close collaboration throughout the supply chain, from the vehicle designer to the component manufacturer to the materials supplier … regardless of what type of composite material you’re using to make projects of this size doable,” Barnes says. ELG worked closely with the OEM to optimize its materials, and the OEM worked with ELG to ensure it had the right design data to design its parts.
ELG’s next step is to set up its first composites recycling center in the United States within the next few years. To facilitate that goal, ELG became a member of IACMI and signed a memorandum of understanding with the institute’s west coast strategic partner – Port Angeles, Wash.-based Composites Recycling Technology Center (CRTC).