For some by-products that arise during the production of natural fiber-reinforced plastics (NFRP), there are still no holistic recycling approaches and technologies. For example, it is not yet possible to fully and sustainably recycle all plant parts and other by-products generated during the production process of NFRP. However, in terms of a resource-conserving and environmentally conscious use of what nature gives us, such a complete utilization is desirable.

In recent months, researchers from the LaNDER³ sub-project Biorefinery - Utilization of regional and renewable raw materials have developed technologies that enable the holistic use of all components and by-products of NFK production from plants such as flax, goldenrod, hemp and nettle as well as plant parts such as leaves.

The research topics in the biorefinery sub-project are very diverse: for example, the development of a special and gentle fiber digestion process, water roasting, which works in a similar way to the fermentation of food, was researched. The researchers also investigated the role of fungi and bacteria in fiber digestion and the utilization of the resulting acids. In addition, the team is developing a recycling plant with which previously unusable leaves can be made usable, for example for the production of biodegradable disposable products and plant pots or biochar.

Fields of application for research:

With the help of water roasting, for example, the team was able to obtain fibers of the highest quality. These are finer, brighter and softer than fibers obtained using conventional technologies. Fibers of this quality are of great interest in the clothing and textile industry.

The researchers were also able to find potential applications for stalks that remain after fiber pulping. For example, they can be used as a sustainable wood substitute in the furniture sector.

The acids produced during fiber pulping can also be used for the production of perfumes, flavors and bioplastics in addition to the biogas utilization already researched in the completed LaNDER³ sub-project Raw materials, resources, energy supply.

In order to develop suitable technologies for this, there is close cooperation with another LaNDER³ research project: the team of the sub-project Material separation processes for aqueous material flows after fiber pulping is investigating which processing of the acids is necessary and possible in order to make them usable for further processing into the above-mentioned products.