The primary role of a ship antifouling coating is to limit the increase
in frictional drag as a result of surface deterioration and biofouling
accumulation. Frictional drag alone can account for as much as 90% of
the total drag on some hull types, even when the hull is relatively
smooth and unfouled. Hence, for a given ship design, the coating
condition is crucial to the performance of ships. Frictional drag in a
ship is directly linked to the interaction between the moving hull and
the surrounding seawater. As the ship moves, a significant mass of water,
sometimes reaching 1/4 or even 1/3 of the total mass of the ship, is
accelerated to a speed close to that of the ship. The consequence of
this is that the engine must deliver additional power to keep constant
speed and thus greater fuel penalties. Therefore, there is a general
consensus of all the ship owners companies that the fouling and
macro-algae attachment to the hulls induces much large propulsion costs
and are also a cause for a large part of the maintenance costs.
Marine biofouling begins to accumulate on the submerged portion of an oceangoing vessel within minutes of making contact with the water. Over time, this accumulation increases the drag of the vessel, causing the physical resistance of the vessel to increase. As a result of fouling drag on the vessel, higher fuel consumption to maintain a given speed or lower speeds at a maintained power will occur. To date, there exists no coating that can provide low initial friction with water and maintain the vessel free from fouling for up to 90 months of exposure to seawater, especially if the vessel has long idle periods or low activity (frequent stays in port). It would also be desirable that these properties could be combined with ease of application and good mechanical properties.
The FOUL-X-SPEL aims to research and develop an alternative for poisonous antifouling coating consisting in extensive research biochemical and chemical research to find a new paint more efficient for antifouling purposes. The FOUL-X-SPEL project takes into consideration the adhesion of microorganisms and, algae to the coated hull surfaces, which are the precursors to later fixation of macro-organisms, and are known to cause serious hydrodynamic penalties themselves. The basic idea concerns the modification of usual hull applications by providing a new antifouling coating, which can provide biocide activity, in order to avoid leaching and to promote a long-term effect of surface protection. This requires the binding through a molecular bridge and to study the effective concentration of the bound active compounds. The new surface coating technology will by this way minimize the surface roughness and improve ship hydrodynamic performance.
The project, following recent advances in knowledge in polymer chemistry, aims to obtain a new low friction antifouling coating which will maintain its biocide activity over the medium to long term.
The process will be optimised in terms of materials, safety and environment, controlling ecotox properties and accomplishing the IMO and EU Regulations.
Propulsion improvement due to average drag reduction;
Validation of low environmental antifouling coating impact and valorization;Energy saving and reduction of fuel costs;
Improvement of ship management and overall costs;
Immobilization period reduction in dry docks for hull repaints. Contribution to environmental regulations
This project aims to demonstrate that is available use the non-dangerous biocides listed by European Union in order obtain a longer cycle of life with a superficial layer containing low concentration of biocide and not subject to leachate migrating for water. The environmental regulations must consider the advantages of this stable antifouling that will perform environmental advantages during the service, repaint and removal of coating waste of hull blasting and cleaning without possibilities of soils and water contamination before the final disposal. The recycling of coating waste will be studied in order to find a better alternative than the disposal in industrial landfills.