Hannover Messe 2019 | transfer | research | nano sciences | technology

Environmentally-friendly coatings for aquaculture nets

Research team at Kiel University presents a new approach for prevention of biofouling at the Hannover Messe



Organisms like algae, mussels or barnacles rapidly colonise surfaces in maritime applications, such as ship hulls. The protective coatings primarily used to date contain substances like copper, which are harmful to the environment. The nets used in fish farming are also largely impregnated with copper-based coatings and release environmentally-toxic copper compounds into the water. A team at Kiel University (CAU) is researching environmentally-friendly polymer coatings to minimise fouling by marine organisms. In the project "CleaNet", together with a manufacturer of fishing nets, they aim to develop a coating material which is specially adapted to the specific requirements of nets in aquaculture. The project, which started on 1 April, is funded by the Federal Ministry for Economic Affairs and Energy (BMWi) and the Central Innovation Programme for SMEs (ZIM), of which €200,000 will go to the CAU. At the Hannover Messe, the team will present the underlying approach and further areas of application such as shipping, industrial food processing or medical technology (CAU booth, Hall 2, CO7).

Many kilogrammes of biomass per square meter may be present if marine organisms colonise the nets which are used in marine and coastal aquaculture. As a result, the supply of oxygen and nutrients inside the nets may be greatly reduced, which has a negative impact on the development of the fish. The mechanical strain due to the extra weight can cause so much damage to the nets that they tear and release the farmed fish into the ocean. In addition to the economic loss for fish farming, many countries like Norway impose high fines for this.

To date, nets colonised with organisms are painstakingly cleaned, frequently replaced, or given protective coatings containing copper. "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 Dr Martina Baum, technical biologist in the "Functional Nanomaterials" working group at the CAU. At the same time, the coating must be resistant to external influences like current or UV radiation. In the newly-launched project, in cooperation with the net manufacturer Mechanische Netzfabrik Walter Kremmin GmbH & Co. KG from Oldenburg, the team aims to develop a material as well as an appropriate coating procedure - right up to market-readiness - which are appropriate for the composition and manufacture of typical commercial nets.

In doing so, Baum can draw on her findings from previous research on environmentally-friendly polymer coatings for painting ships. The anti-biofouling paint, which she developed in close cooperation with the company Phi-Stone AG, reduces the colonisation by organisms of ship hulls, and releases no environmentally-harmful substances into the sea - unlike the widely-used self-polishing coatings.

"The paint is based on a polymer composite of polythiourethane (PTU) and specially-shaped ceramic particles. These improve the mechanical properties of the coating and ensure an extremely smooth surface, which is very difficult for organisms to attach themselves to," explained Baum. These findings must now be applied to the specific requirements of nets in aquaculture. For this purpose, tests will be carried out under real conditions at a Kiel fish farm, and a climate test for long-term coatings is planned with Phi-Stone.

From 1 - 5 April 2019, the research team will present their anti-biofouling concept and its potential applications at the CAU booth at the Hannover Messe (Hall 2, Research & Technology, booth C07). On Thursday 4 April at 12:30pm, Dr Martina Baum will give a presentation in English called "Environmentally-friendly polymer blend with potential as fouling-release coating". At 3:30pm, doctoral researcher in the project Haoyi Qiu will deliver the presentation in Chinese.

Key facts:

  • What? Presentation: “Environmentally-friendly polymer blend with potential as fouling-release coating” and an exhibit
  • Who?   Dr Martina Baum and Haoyi Qiu
  • When? The presentation will take place on Thursday 4 April at 12:30pm (in English) and at 3:30pm (in Chinese). The exhibit can be seen from 1 to 5 April.
  • Where? CAU booth C07 in Hall 2 “Research & Technology”, exhibition grounds (Nord 2 entrance), 30521 Hanover

Project information:
Title: CleaNet - fouling-release coating for aquaculture nets
Head: Kiel University, Dr Martina Baum
Project partners: Mechanische Netzfabrik Walter Kremmin GmbH & Co. KG
Funding from: Federal Ministry for Economic Affairs and Energy (BMWi) and the Central Innovation Programme for SMEs (ZIM)
Funding amount: €200,000 for the CAU
Duration of funding: 01.04.2018 – 31.03.2020

© Martina Baum

Marine organisms like barnacles or algae rapidly colonise the nets used for fish farming. The weight puts a strain on the nets, and cleaning them is time-consuming.

© HP Voiß

The organisms are also a big problem for ships. They damage the surface, and increase fuel consumption due to greater frictional drag.

Ship wall
© Martina Baum

With the Kiel research team’s environmentally-friendly coating, the barnacles and mussels can be brushed off quickly because they are only lightly attached.

CAU@Hannover Messe

In 2019, Kiel University (CAU) will once again present its excellent research at the Hannover Messe. Under the motto "Ways to Solutions" the state university demonstrates: science affects society in many different ways. It contributes to exchanges, solves tricky problems and creates new scenarios. All this awaits guests in Hall 2 (Research & Technology). This time, together with our partners: State of Schleswig-Holstein, the City of Kiel and the European XFEL. Participation at the trade show will focus on presentations and exhibits associated with cutting-edge research, the transfer of knowledge, patents and initiatives to establish companies. Presentations and panel discussions will round off the varied programme during the week. All information can be found here: www.uni-kiel.de/hannovermesse

Details, which are only a millionth of a millimetre in size: this is what the priority research area "Kiel Nano, Surface and Interface Science – KiNSIS" at Kiel University has been working on. In the nano-cosmos, different laws prevail than in the macroscopic world - those of quantum physics. Through intensive, interdisciplinary cooperation between physics, chemistry, engineering and life sciences, the priority research area aims to understand the systems in this dimension and to implement the findings in an application-oriented manner. Molecular machines, innovative sensors, bionic materials, quantum computers, advanced therapies and much more could be the result. More information at www.kinsis.uni-kiel.de

(Kopie 4)

Dr Martina Baum
Kiel University
Functional Nanomaterials working group
+49 431 880-6195


Julia Siekmann
Science communication
Priority research area Kiel Nano, Surface and Interface Science (KiNSIS)