11 May 2022
Authored by Simon Doran, HullWiper MD.
It wasn’t until I first saw the hull of a vessel as a navy diver that I truly realised what a dirty business biofouling is! When you’re 10m (or more) underwater, you get to see the blue heart of our ocean; it’s a force to be reckoned with, but when your job is to find bad things attached to a vessel’s hull, or search ports for more bad things, you also recognise just how fragile it is. As I have matured (gotten old), I have – in various capacities – been determined to make a difference in preserving the safety of divers and the health of our oceans.
With more than 37 years’ experience in the subsea sector, I think of the ocean as my office. As a Royal Navy Diver, GM for a commercial diving company specialising in underwater maintenance, repair, and support systems and now as MD for HullWiper, one common threat I’ve encountered with ships bottoms is marine biofouling.
It is well known that biofouling is a drag on the shipping industry and our marine ecosystem. The accumulation and growth of algae, marine sessile organisms, barnacles, and mussels (to name a few) on oceangoing vessels adversely affect their operational efficiency. The decrease in vessel speed results in higher fuel consumption and Greenhouse Gas Emissions (GHG). And we cannot ignore the fact that the transfer of invasive aquatic species (IAS) into foreign waters poses a major threat to the health of local marine ecosystems.
Routine in-water hull cleaning addresses these serious issues, and it works. It is now well recognised by our industry as an effective method to reduce biofouling and address the environmental impacts.
Not all fouling is the same
The removal of early-stage fouling development (microfouling) at regular intervals delivers the best results. It’s like brushing your teeth – we clean daily to prevent the build-up of plague and an expensive visit to the dentist. A paper published in February by researchers for the Frontiers in Marine Science described one method of hull cleaning as “the gentle, habitual and frequent mechanical maintenance of submerged ships' hulls in order to remain free from the effects of biofouling”. The study notes that regular maintenance minimises the damage to expensive anti-fouling coatings.
Macrofouling occurs when these pesky living creatures are left to develop and grow, often times damaging expensive anti-fouling hull coatings. This can lead to dry docking sessions - and the last thing an owner wants is a costly and time-consuming cleaning and repair job!
I have met a lot of ship owners and operators over the years, and not one has ever told me that hull cleaning was a bad idea. Further, everyone agrees that using a safe, cost-effective, and eco-friendly method is vital in reducing their operational costs and the vessels carbon footprint.
The way ahead is now
HullWiper’s Remotely Operated Vehicle (ROV) is a first of its kind. Launched in the UAE in 2013, we have expanded our operational bases to include Australia, Gibraltar, Guinea, Mauritius, Panama, Singapore, Sri Lanka, South Korea, and Sweden. More locations are in the pipeline!
Internationally recognised for its advanced capabilities, our diver-and brush-free ROV reduces damage to antifouling coatings and eliminates the release of contaminants into local ports waters. Cleaning can be done day or night, during cargo or bunker fuel operations and in most weather conditions. The filtration system collects all removed fouling during the cleaning procedure for safe disposal onshore with a locally approved environmental waste company.
Our Onboard Solution is a conceptual extension of our service, giving greater control and flexibility to ship owners and operators. The ROV can be included in the design phase for newbuilds by way of an on-deck solution, door, or hatch in the side of the hull or through a moon pool, which allows vessels such as cruise liners, LNG, cargo carriers etc. to perform a partial or full hull clean on demand, without disruption to tight schedules.
As a diver, the ocean is part of my DNA and I bleed saltwater. The work we are doing with hull cleaning matters to us, and protecting our blue planet is as important to the HullWiper family as it is to you.
· Numerous research studies conducted on small-sized test panels demonstrated the feasibility of in-water grooming as an effective method for preventing fouling. These tests were later conducted on larger vessels, further proving the method's effectiveness.
· Through additional studies, researchers discovered that when utilising the hull roughness analyser, coating roughness measurements indicated that the groomed surfaces became smoother. The ungroomed coatings increased in roughness which caused damage to the coating due to cleaning and the remains of fouling that had not completely been removed.