The role of coatings in biochemical antifouling is being recognized by IMO, and the biochemical antifouling instruction manual is now being prepared. It is required to adopt an effective biochemical antifouling management system for the hull and concave parts (such as submarine valve box and bow thruster). The underwater and docking procedures will include where and when inspections should be carried out, how to make records, and guidance for port authorities on how to supervise. This instruction manual is expected to lead to more frequent and long-term docking and / or water cleaning, because it may take longer to clean the concave parts, and different parts of the hull need different coatings.

 

Australian Commercial Division services (CDS) has developed the patented hull surface treatment (HST) technology and won many environmental awards in 2009.  This diver free method can remove the early growth of aquatic organisms in the hull and concave parts. At present, this method can only be used in Australian waters. It needs to heat the seawater to about 60-70 ℃ and remove algae, seaweed and newborn barnacle spores and shellfish without washing with a brush or high-pressure water flow. "It won't hurt the paint coating," said Keith Johnson, chairman of CDs. "In fact, it has some advantage of reactivation, which can make the final leaching layer leave the outer surface, so that the antifouling paint can give full play to its original function." Some people think that the current hull coatings can not obtain the effect of toxic TBT coatings. Mr. Johnson sees the trend of using cheaper coatings for ship owners, although this coating needs HST treatment every 6 months. Compared with some more expensive coatings, regular hull cleaning can help reduce costs and improve fuel efficiency. Mr. Johnson believes that it is difficult to persuade and educate ship owners, but it is still necessary to make them understand that the new coating layer needs to be maintained within a year. "We continue to take underwater photos to prove to ship owners that their hull has seriously bred marine organisms six months after undocking. They are often shocked and can't imagine that the marine organisms on the hull will grow so fast. The best way to eliminate aquatic organisms is to kill aquatic organisms in the early stage!"

 

Another preferred hull cleaning technology is currently being tested in Australia and New Zealand, but has been actually applied in the UK. This is the ultrasonic technology developed by Blue & greenmarine. This technology is to install an ultrasonic system on the inner surface of the outer hull, so as to form an ultrasonic induced cavitation layer, resulting in an environment where aquatic organisms can not grow. Experiments on yachts and work boats have achieved encouraging results.

 

After the test of Casper hull and propeller performance monitoring system developed by propulsion dynamics, TEEKAY now monitors 90 ships every month to determine their resistance and whether the hull needs to be cleaned. The report presented includes data analysis of wind speed, sea state, draft and trim. By comparing with sister ships, we can master the dirty bottom of different hull and its influence on speed and fuel consumption. "TEEKAY now has an efficient fleet," said Victor Armstrong, manager of ship optimization Department of TEEKAY marine services, "But we also want to confirm that there are effective monitoring tools to help us achieve our goals. In these difficult days, we need to confirm that we will not consume excess fuel and pay excess expenses due to the deterioration of hull and propeller performance." Casper's data is directly sent to propulsion dynamics, and the processing results are returned to the technicians on board and on shore. "We are optimistic about the performance of the fleet, and we can prepare specific reports for the team and fleet, so that we can pay attention to performance deviations," Mr. Armstrong said. Reports can be used to determine performance and assess charter costs.

 

The research on high performance coatings is still in progress. The research on resistance is being carried out by the Maritime Research Institute, Netherlands, Marin, which involves special coatings and bubble lubrication of hull. The report published in October 2009 shows that bubble lubrication has no significant effect on the resistance or maneuverability of the model or real inland river ship tested. The results show that only improving the ship and adding bubbles can not reduce the resistance. Obviously, a special coating is required to retain bubbles near the hull surface.