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Winning the next battle against invasive marine species A Norwegian start-up is solving the twin challenges of operational efficiency and environmental protection, with a little help from the Orcelle Award brutal in its effects on the coating and potentially harmful to the environment. “The brushing can do more harm than good because it is aggressive and gives uneven results. You can’t maintain pressure and have poor visibility and may end up damaging the paint and creating conditions that are even better for new growth,” he says. For cost reasons, operators want to be able to clean hulls within the timespan of normal cargo operations ideally when cargo operations are taking place. At many ports it is hard to get permission to do this for safety reasons. Local environmental agencies may not approve brush cleaning because removing non-native shells creates the risk that live organisms are transferred to the local seabed. “It’s a paradox. Everyone wants to reduce their GHG emissions but not for vessels to be cleaned in their ports,” he adds.
Reducing costs and emissions
Co-founder and CEO of ECOsubsea Tor Østervold The ratification of the IMO’s Ballast Water Management Convention is a milestone in the battle to manage the spread of invasive aquatic species. Yet despite the importance of the decision, regulators and shipowners alike have long recognised that the spread of invasive species through fouling of ship hulls is as big - if not a bigger - problem. The IMO has already put in place guidelines for the control and management of ships’ biofouling that aim to minimise the transfer of invasive aquatic species. Co-founder and CEO of ECOsubsea Tor Østervold believes the issue has the potential to be even more important in the years ahead. “Now that IMO members have ratified the BWM Convention, the next controls, dealing with the spread through biofouling will come much faster,” he says. “But I think the positive commercial and environmental benefits of reduced fuel consumption and lower air emissions from having a hull free of fouling will be obvious to the industry as a whole.”
ECOsubsea was founded with the aim of solving this problem and by setting out to make a difference to operating costs as well as environmental protection, it has quickly found acceptance. The ECOsubsea solution is a remotely operated vehicle which removes the need for divers and uses a newly-developed high pressure water cleaning principle called ‘soft jets’, which is gentler on the hull than mechanical cleaning. The process provides an accurate inspection of the hull condition and cleaning progress can be monitored by cameras. In addition to minimising damage to the coating, of interest to Wallenius Wilhelmsen Logistics (WWL) was its ability to act as a vacuum cleaner, locking on to the hull so that the waste water is pumped back to a collection tank. No waste is released to the local environment and the residue has application as biomass fertilizer.
Overcoming hull resistance When slime builds up on a ship’s hull, it attracts aquatic organisms that must be quickly removed before they can build up. Once fouling becomes established the mechanical cleaning required to remove it presents a challenge to safety, coatings management and to marine pollution. Owners face an unpalatable choice: wait until dry dock and see performance reduce over time or clean when the ship is in the water, a difficult and dangerous option which risks further spread of non-native organisms. In-water hull cleaning is traditionally carried out by divers using portable brushes, a process Geir Fagerheim, Head of Fleet Operations, Ocean Operations, Wallenius Wilhelmsen Logistics AS, describes as
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Geir Fagerheim, Head of Fleet Operations, Ocean Operations, Wallenius Wilhelmsen Logistics AS