The activities of the Linz-based start-up Carbon Cleanup bring an important sustainability and environmental aspect into focus: how to deal with the large amount of carbon fiber materials in products that are reaching the end of their life or that are generated as waste during production? But what are carbon fibers and where are they used? Carbon fibers are based on petroleum products and are manufactured using chemicals and high levels of thermal energy. They are very light and help to improve the strength of plastics. Carbon fiber-reinforced plastics are so-called composite materials that are used on a large scale in many demanding technical applications, especially where strength combined with low weight is of great importance. These include the aerospace and automotive sectors.

Data from the EU research project ReCreate, in which Carbon Cleanup is involved, shows the large quantities of composite waste that can be expected in Europe alone by 2040. In the wind turbine rotor blade segment, the total is over 200,000 tons (including waste generated during production), in the sail, motor and electric boat segment it is over 400,000 tons and for aircraft it is almost 30,000 tons. The project report also mentions the automotive, construction and sports equipment sectors without a waste volume forecast.

“We are dealing with a first-world problem here, where intelligent solutions for recyclability are required. I don’t think it’s wise to dump materials that can still be used to make high-quality products. What’s more, landfilling such materials is already prohibited in Austria and other countries anyway,” says Carbon Cleanup co-founder and CEO Jörg Radanitsch. And he adds: “In general, I am a strong advocate of converting and reusing all materials that we have already produced or put into circulation on this earth.”

Mobile recycling equipment

The cleantech start-up has been developing a solution for this since 2020. Carbon Cleanup relies on container-sized mobile recycling equipment for composite materials that can be set up directly on the customer’s premises. “There have already been some more or less successful trials with large-scale recycling plants; our niche is mobile, decentralized and networked microfactories,” reports the CEO. The prototype Carbon Cleanup Unit One was followed by the first series-produced recycling system Carbon Cleanup Unit #2 with an annual output of 300 tons by mid-2024. The system has undergone severe certification processes and meets the required standards, including compliance with TÜV and CE product safety standards and national waste management regulations. The start-up plans to produce two more series systems by the end of 2024 and 100 units by 2030. “In such cases, regardless of whether there are many microfactories or conventional factories in a group of companies, it will be essential to network and operate these units intelligently using edge technology,” says Günther Schallmeiner, head of the Siemens branch for Upper Austria.

As an alternative to landfill, Carbon Cleanup offers customers the recycling service. Companies such as the Upper Austrian aviation supplier FACC or the German automotive supplier SGL Carbon pay that composite waste is taken from them in the same way as for any other disposal. Another type of customer are those companies that use the start-up’s recycled products in their products, for example KTM. “We are working with KTM on the smallest possible closed loop. We turn the waste streams from various production processes into recycled material, which in turn is used in KTM products such as a motorcycle seat,” says Radanitsch.

The result of the recycling process in Carbon Cleanup’s units are homogeneous fiber blends or fiber fillers. These recycled fibers are used in three product groups: Firstly, as a material for 3D printing – for private applications as well as for very large 3D-printed shapes, such as aircraft wings. Secondly, for injection molding processes for the production of technical plastic components such as plates for ski bindings. And thirdly, for so-called random fiber or forged carbon components – for example, cross beams in the radiator area of certain Audi models are made of this material.

© Carbon Cleanup

The Carbon Cleanup team around co-founder and CEO Jörg Radanitsch (3rd from right) and CTO Jakob Schlosser (4th from right).

The origins of Carbon Cleanup actually lie in steel production. “During my time as a consultant, we conducted trials with steelworks to introduce carbon into steel as a substitute for coke. This project is still ongoing. It was only later that the plastic aspect was added and then we realized that we could make a lot more out of it. After I realized that there was no processing technology for composite material that was widely available and covered the safety requirements, I developed a process that was also patented,” explains Jörg Radanitsch.

Patented processing systems

The patent was granted for the only mobile, self-contained and dust-protected composite material processing system that automatically adjusts its machine parameters. The process that takes place in the units is a dry, mechanical process that uses as little energy as possible. The patented operational management of the system is characterized by digital monitoring and readjustment. “The Siemens components that we use in the units are the enabler that allow us to implement the patent,” says Radanitsch. A Siemens drive package is used in every Carbon Cleanup Unit. “The heart of the system is the SIMATIC controller, plus frequency converters, panels and switches as network components for data transfer,” says Klaus Baumann, Head of Industrial Sales for the Upper Austria region at Siemens Austria.

© Carbon Cleanup

The Siemens components in the Carbon Cleanup Units ensure the implementation of the patented treatment process.

A special feature of the carbon cleanup concept is that recycling is based on the end result. “We develop the recycling concept for this material as soon as the composite component is put into circulation. What does reconditioning cost? What kind of effort is that? What is the recovered recyclate worth?,” says Radanitsch. To determine the value of its own recycled products, an AI-supported system was developed by Carbon Cleanup to visually identify the raw materials that are fed into the plant. “We are constantly collecting process data with our systems through customer orders or in research projects and now have a strategic data set that puts us in a position where we can say that we need exactly these and those parts from the total amount of offcuts and scrap components in order to obtain a specific recycled material with the required properties at the end of the process and achieve a defined market price,” reports Jakob Schlosser, CTO at Carbon Cleanup.

CEO Radanitsch comments on future developments as follows: “With our process, we produce recycled materials that form a new group of materials. We are transforming waste, which will increasingly be banned from landfill in the future, into a high-quality material.” Commenting on the market outlook, he says: “We are currently in an early phase, as we were at the beginning of waste paper recycling. The market for recycled fibers has yet to develop. When it starts, it will be very big because the recyclate is very cheap compared to new material and significantly reduces the CO₂ footprint. Another market driver will be the fact that recycled materials will be required to a certain extent in the automotive sector in the future. This group of materials is also still very new in aviation and will only play a greater role in the future. I expect that we will see a significant volume flow in three years at the earliest, which will not only stimulate our business model, but also make an important contribution to sustainability.”