The barnacles, mussels and algae that get attached to ship’s hulls not only attack the vessel’s protective coating but also increase its flow resistance. Bio-fouling – to use the specialist term – can increase a ship’s fuel consumption by up to 40% and is estimated to cost the global shipping industry over US$150 bn a year. Currently, around 80,000 t of anti-fouling coatings are applied worldwide, with an overall bill for ship owners and operators coming to about US$4 bn a year. The problematic issue is that most marine coatings contain copper. As they get worn off, poisonous substances are released into the water. As a result, organostannic coatings have already been banned and copper-based coatings could well be prohibited in 2018.
Barnacles on a ship hull.
But here’s the good news. In collaboration with scientists from Kiel University, researchers from the Kiel-based nano-research start-up Phi-Stone has developed a solvent-free marine coating made of polythiourethane (PTU) and specially shaped ceramic particles. This innovative nano-material coating is so smooth those nasty barnacles, mussels and algae simply cannot get a grip. That means that anti-biocorrosion coatings will protect a ship’s hull much longer and any bio-fouling can simply be brushed off this ultra-smooth coating.
The magnitude of the Kiel nano-researchers’ achievement has already been recognised in China where their pioneering marine coating won the Global Marine Technology Entrepreneurship Competition 2017 in Qingdao.