Closing the loop, INEOS Team UK has a waste segregation system to help the team on the shop floor collect scrap prepreg and cured and dry cloth offcuts for transport to ELG, where they are recovered using a pyrolysis process. Once processed, the fibers that contain high enough mechanical properties are used to produce the non-woven mat, such as those used to make the cradles and molds. Some of the scrap carbon fiber collected from INEOS Team UK is being recycled into the oil and gas industry. The remainder is milled to become an additive for adhesives.
“It’s been a long journey, but I believe the CFRP and marine industries are finally recognizing the importance of recycling carbon fiber,” says Barnes.
Manufacturing: Adopting New Technologies
Marine Concepts in Sarasota, Fla., is a design, engineering, composite tooling and manufacturing company that makes CNC patterns, composite molds and composite parts for the marine industry. “We pay attention to sustainability in a broad sense, particularly identifying ways to remove excess millings and foam from our facility in a friendly manner,” says Ross Kennedy, director of business development for Marine Concepts.
Marine Concepts sources tooling resins from a company that specializes in earth-friendly resins and gel coats. “We are able to use them for 95% of what we do,” says Kennedy. “These environmentally-friendly materials perform as well, if not better, for us than the resins we used to use.” The resins are low in hazardous air pollutants (HAP), low in volatile organic compounds (VOCs) and MACT-compliant. “This is better for our workers,” says Kennedy. “They aren’t breathing in volatile materials.”
It is in the production phase that Marine Concepts has invested most significantly in sustainability, with the addition of closed mold infusion processes. “We not only make some of our tooling using closed molding, we also make a large amount of composite parts for our customers this way,” notes Kennedy. “By vacuum bagging the part and then infusing, we make a better part – specifically lighter through infusion – and we limit the styrene and VOCs released into the atmosphere.”
For tooling, an environmentally-friendly gel coat is followed by fiberglass or carbon fiber laminates. Once the laminate is in place, the part is bagged with a manifold in place. After the bag is sealed, the laminate is wetted out with the low VOC vinyl ester or epoxy, depending on the design. “Every void in the laminate is filled. The ability to keep the resin within the bag traps the emissions, preventing them from going airborne,” says Kennedy. While the company makes a few tools using epoxy resin systems that require an oven, most often, parts made with the environmentally-friendly vinyl ester resin are air cured unless higher service temperatures are required.