The Lenzing Group, a global company in specialty fibers based on the renewable material wood introduced the botanic solution for marine application, in particular for aquatic farming, to the public at the Techtextil Frankfurt Fair.
The wood-based LENZING™ branded lyocell fibers are used for the construction of ropes and nets in order to support the cultivation of marine cultures such as mollusks, mussels, and edible seaweed to reduce plastic in the sea.
Plastic: a serious problem
Annually, about 8 million metric tons of plastics end up in the ocean, resulting in an estimated 165 million tons of plastic debris, currently floating in the marine environment, threatening the health and safety of marine life. The loss of conventionally used synthetic fibers and plastics in the ocean accounts for 80 % of all marine pollution.
The development of Lyocell fibers help to reduce the annual plastic quantity in the marine environment
This is not only dangerous for marine life but also for humans as we consume some of these microplastics through our food. “The development of 100% wood-based mussel nets with LENZING™ Lyocell fibers contribute to the reduction of the annual plastic quantity in the marine environment”, says Marine Crnoja-Cosic, Head of Application Development New Business Areas.
Sustainable Innovation
The Lenzing Group initiated a project in collaboration with two major partners, Sächsisches Textilforschungsinstitut e.V. (STFI) and FIUM GmbH & Co. KG – Institut für Fisch & Umwelt (FIUM) in order to develop a sustainable solution for the marine industry, which does not compromise mechanical performance. There are many different methods of using textile structures as a support for the growth of marine organisms.
Fiber Features
The important feature of the present invention is that the textile structure is made of wood-based cellulosic fibers. This gives the advantage that any of the textile structure which is released into the environment due to accident, storm damage, negligence, or any other cause will degrade in a reasonable time and not leave non-degradable residues.
Material characteristics
Up to now, nylon and polypropylene are most commonly used for rope and net materials. Although these materials are durable and have sufficient strength, they do not have a natural origin and are not marine biodegradable. They stay in the oceans for years.
Nets and ropes consisting out of LENZING™ Lyocell fibers proved that they have sufficient strength to carry the weight of the growing cultures without breakage and have the big advantage of biodegradability in the oceans.
Proved by tests
The cooperation partner Sächsisches Textilforschungsinstitut e.V. constructed different prototypes and replicates out of LENZING™ Lyocell fibers in March 2018. Thereafter, an initial underwater material test was started in the Baltic Sea.
The prototypes were installed in 6 to 10 meters depth at an artificial reef platform in Rostock Nienhagen. The objective of the trial was to prove that marine applications produced out of LENZING™ Lyocell fibers can fulfill the key properties of conventional marine supports, which are sufficient strength to carry the weights of the growing cultures without breakage. Moreover, the trial investigated if LENZING™ Lyocell fibers represent a pleasant environment for particular marine organisms and also prove the marine biodegradability after usage.
Compostability and biodegradability
All LENZING™ Lyocell fibers represent an appealing growing material for marine organisms
After four organized dives by project partner FIUM, the first test results were available. All LENZING™ Lyocell fibers represent an appealing growing material for marine organisms. Overall 14 different sea dwellers like blue mussels, crustaceans, echinoderms, or snails adhered to the test material. First test results regarding performance and biodegradability were promising.
Sustainability advantages in aquatic farming are particularly evident, given the fact that the material is being used directly in the oceanic ecosystem. LENZING™ Lyocell Standard fibers are certified as compostable and biodegradable under industrial, home, soil, and also under marine conditions.
If pieces of the nets break off, they will harmlessly decompose and have no influence on marine organisms. In order to close the sustainability loop, the nets can be composted after harvesting and processing.
Further developments
“This development brings sustainable solutions to aquatic farming encouraging Lenzing to assess and establish further steps towards commercialization, together with innovative value chain partners”, says Crnoja-Cosic.
“Furthermore, future development will focus on optimizing the net's construction for more durable products broadening the scope of 100% Lyocell-based marine nets in the marine environment,” conclude Crnoja-Cosic.
