Carbonfaserhaltige Reststoffe als Sekundärrohstoff – Einsatz in der Pyrometallurgie
- Lightweighting is a key technology for tackling the challenges of the 21st century, in particular climate change. Lightweighting contributes to decreasing CO2 emissions, improves resource efficiency and supports the transition to sustainable mobility. In particular, carbon fibers (CF) and carbon fiber-reinforced plastics (CFRP) play a central role in various industries such as aviation, wind power and electric mobility. With the increasing demand, the waste streams of CF are also growing, and their recycling is crucial for environmental compatibility and the circular economy. The difficulty of CF recycling is to separate the CF from the polymer matrix to obtain high-quality recycling materials. Processes such as solvolysis and pyrolysis are used, with pyrolysis being the more commonly implemented. However, the process for obtaining recycled carbon fibers (rCF) also has disadvantages, since the fiber lengths and qualities can be affected by the recycling processes. Safety aspects areLightweighting is a key technology for tackling the challenges of the 21st century, in particular climate change. Lightweighting contributes to decreasing CO2 emissions, improves resource efficiency and supports the transition to sustainable mobility. In particular, carbon fibers (CF) and carbon fiber-reinforced plastics (CFRP) play a central role in various industries such as aviation, wind power and electric mobility. With the increasing demand, the waste streams of CF are also growing, and their recycling is crucial for environmental compatibility and the circular economy. The difficulty of CF recycling is to separate the CF from the polymer matrix to obtain high-quality recycling materials. Processes such as solvolysis and pyrolysis are used, with pyrolysis being the more commonly implemented. However, the process for obtaining recycled carbon fibers (rCF) also has disadvantages, since the fiber lengths and qualities can be affected by the recycling processes. Safety aspects are also important, since carbon fiber fragments can be potentially harmful. Processes must be developed for treating carbon fiber waste streams, that ensure safety, since landfilling is not possible due to the plastic matrix. Large-scale experiments have shown that the thermal recovery of CF in waste incinerators is incomplete, which is due to the chemical structure of CF. Pyrometallurgical utilization of CF is considered a promising approach. Here, CF can be chemically utilized in these high-temperature processes in such a way that their conversion is improved while minimizing the formation of fragments that are harmful. In this context, studies on the reactivity of CF in such processes are important to verify the efficiency and safety of the procedures. In summary, the safe and efficient use of CF waste not only contributes to the circular economy but also promotes the decarbonization of the steel industry. It is crucial to develop suitable processes to protect the environment and the health of workers while maintaining the value creation of CF.…

