Research: Green Antifoulant Protects Netting
To provide an environmentally friendly antifoulant option for nets used in fish farming, researchers based out of Kiel University (Kiel, Germany) are researching using polymer coatings as an alternative—an endeavor that aims to create a coating specifically adapted to the demands of nets in water.
The project, known as CleaNet and started April 1, is being developed in cooperation with Phi-Stone AG (Kiel, Germany) and in collaboration with net manufacturer Mechanische Netzfabrik Walter Kremmin GmbH & Co. KG (Oldenburg, Germany).
Aside from acting as a deterrent to keep marine life from attaching to fishing nets, CleaNet also aims to help alleviate the associated mechanical strain that can cause tears in netting, releasing farmed fish back into the ocean.
Antifoulant Coating for Netting
Customarily, nets that have organisms attached are cleaned, replaced or given a copper-based protective coating.
"With our environmentally-friendly coating, we want to reduce the fouling on nets so that they can be cleaned easily and cost-effectively, or the organisms are displaced by the water current," said Martina Baum, technical biologist in the "Functional Nanomaterials" working group at Keil.
In developing the coating, the team must account for external influences, such as current and UV radiation, and its impact on the product. The team is also working on developing a coating process that is appropriate for the production and composition of commercial nets.
To guide the endeavor, Baum plans to draw on previous research into polymer coatings for painting ships.
"The paint is based on a polymer composite of polythiourethane and specially-shaped ceramic particles,” said Baum. “These improve the mechanical properties of the coating and ensure an extremely smooth surface, which is very difficult for organisms to attach themselves to.”
Moving forward, real-world testing will be carried out at a Kiel fish farm, and climate testing for long-term coatings will be conducted with Phi-Stone. The research project received financial support from both the Federal Ministry for Economic Affairs and Energy and the Central Innovation Programme for SMEs.