Recycling boats by pyrolysis for energy autonomy
The treatment of composites remains the most complex part of the yacht dismantling process. Indeed, wooden fittings, electronic equipment or metals have channels developed outside the boating industry and their management is more controlled. However, the composites used in yachting, generally thermosetting, are currently crushed to be burned or stored, an unsatisfactory solution.
Among the various industrialists working on this issue, the Swiss company Composite Recycling, presented at Nautic 2022 its technology based on the principles of pyrolysis, as explained by Guillaume Perben, co-founder of the company. "It is the principle of pyrolysis known for ovens. The hull of the boat is cut into plates of 1.5 to 2 meters long and 1 meter wide. It is then heated without oxygen, between 400 and 500°C, against 1200° to produce fiberglass. The gas produced is burned to heat the oven. By treating 100 kg of composite, 10 kg of gas are produced and only 7 kg are consumed. The remainder is stored to start the oven at the next heating. Next to that, we recover the pyrolysis oil and fibers."
Reusable fibers
Adapted to all thermosetting resins, such as polyester, vinylester and epoxy, the process also works with PVC, provided that the quantity is well known in order to collect the hydrochloric acid that it releases. Beyond the pyrolysis oil, which is sought after in the chemical industry, its main interest is to recover long fibers that can be used for new composite parts. Guillaume Perben explains: "Our reflection started from the fact that pyrolysis was always done after grinding, thus losing the fiber. Here, by starting to cut long pieces to put in the furnace, we manage to recover the fibers. After cleaning, they can be reused and retain 95% of their mechanical properties."
Mobile units for APER sites
On the occasion of Nautic 2022, APER, the organization in charge of yacht dismantling in France, has signed an agreement with Composite Recycling for the development of containerized and mobile pyrolysis units. Rotating on the different sites of the APER network, they will simplify logistics, avoiding the transfer of boats and offering a more sustainable alternative than the simple "energy recovery"
The first unit to validate the concept is expected by the end of 2023. Its projected capacity is 2 tons of waste processed per day. Composite Recycling and APER have a target of 12 containers, not including the large recycling pool related to production offcuts.
