Biofouling management is facing increasing pressures, from post-Covid challenges to a ramp up in national regulations
Managing biofouling during layup, idling or at slower speeds webinar, part of Riviera Maritime Media’s Marine Coatings Webinar Week, supported by AMPP, examined the challenges and how to overcome them.
Panellist Lonza Solutions associate director, regulatory affairs, Carsten Baehr told the webinar, “Today, conditions are rapidly changing, from being idled and laid up to boom time as we have seen coming out of the Covid downturn, with a 30% increase in activity over just a few months.
That alone is extremely challenging, but there are other demands, from increased sustainable shipping through national biofouling regulations. IMO’s sustainable strategy, sustainable use of biocides and an increasing awareness of all stakeholders… all that brings increasing pressure to effectively manage biofouling.
He added there was also the issue of climate change, which is changing the parameters of waters and the fouling communities within. “Having an effective biofouling solution is extremely important,” he summed up.
Mr Baehr explained that key to effective antifouling are paints and coatings, which power the performance and protection. “There are many advantages that come with having effective biofouling solution, what brings this efficiency to paints are the antifouling active substances,” said Mr Baehr.
But there are large challenges to be faced. Mr Baehr said, “While affective antifoulings need active substances that power coatings, these are under significant threat from global regulation changes that impact effective antifoulings. There are several examples where new or evolving regulations have led to either restrictions or even a ban in certain substances.”
These range from the IMO International Convention on the Control of Harmful Anti‐fouling Systems on Ships (2001, amended 2021); Korean Consumer Chemical Products and Biocides Safety Act (Korean Biocidal Product Regulation, 2018); European Biocidal Products Regulation (since 2012); Malaysian Pesticides Act (since 1974).
Mr Baehr said, “What is needed to overcome pressures and threats are innovative solutions to make sure that effective marine antifoulings remain available today and in the future”
This is where Lonza Solutions’ new product Umigard comes in – Mr Baehr called it a “breakthrough innovation for marine antifouling. It is our answer to bring effective antifouling to you today and in the future.”
The product is a novel chelate complex and co‐formulant for use in marine paints. Mr Baehr said it significantly improves antifouling efficacy and as such is not a biocidal active substance. It boosts efficacy by increasing the residency time of antifouling substances at the water‐interface and increases the hydrophobicity, hardness, and scratch resistance of antifouling coatings.
Its performance has been confirmed in extensive inhouse performance testing (static and dynamic), there is ongoing customer testing and early adopters have already been identified.
Mr Baehr added, “The value proposition that Umigard comes with is a performance increase, boosting the efficacy of antifouling paint products and it brings cost reduction, where comparable efficacy can be obtained at significantly reduced biocide loadings. It also comes with an improved environmental profile, where Umigard minimises cuprous oxide levels and brings increased efficacy to cuprous oxide-free antifouling.”
Elsewhere, the issues of managing biofouling during idling and slow speeds was highlighted. Panellist Safinah Group general manager marine consulting Carl Barnes said, “Managing biofouling, particularly during vessel lay ups, idling and slow speeds, all bring a particular challenge to whatever fouling control coatings are being used.”
He explained, “Generally, fouling control products are formulated to give consistent anti-fouling performance under trading conditions; the majority of vessels are trading and moving, so they [fouling control products] are unlikely to be as effective during periods of lower activity and significant static periods.”
He pointed out that most fouling generally occurs when vessels are running at below 5-6 knots, and if in they are in a significant long static period it is a “major risk”. The consequences of fouling can result in a significant increase in drag on the vessel, somewhere between 25% and up to 80% for heavy shell barnacle fouling, Mr Barnes said.
Problems arise as antifouling schemes are generally designed related to vessel speed activity and intended service period. There is a formation of a leached layer at the surface of antifouling, the area where the biocide is released to seawater. “During normal trading when the vessel is moving, this layer will polish away and dissolve off with the movement of seawater, exposing fresh antifouling ie, exposing fresh biocide to prevent fouling build up,” said Mr Barnes, warning that in times of static activity, the layer will continue to build – preventing the release of biocide to stop fouling.
Mr Barnes warned, “There is no silver bullet to prevent fouling under these conditions. If in drydock, knowing the vessel will go to a period of lower activity, there are some things you can do such as a faster polishing system designed for lower activity vessels.”
Looking at longer static periods, Mr Barnes said cleaning might be the way forward. But challenges include the practicality of cleaning and locations in the world where the vessels can be cleaned, which is much more restricted than five to 10 years ago.
He spoke about other potential solutions, “Some products are pretty good under static conditions, but you need independent data to understand this. If going to lay up or lower activity in service, there are several reactive solutions; regular inspections and cleaning are a good practice, but there are challenges.”
For longer static periods, the vessel can be moved every one to two weeks, which works for both biocide and foul release systems – typically 10-12 knots for four to six hours.
Mr Barnes advised, “For any of these things, work with the paint supplier of the product on the vessel and get them involved as they have good knowledge.”
He summed up, “Key to making a good, informed decision on fouling control selection is clearly understanding what the expected trading conditions are, having some independent data of fouling control product performance and really understanding what your expectations are. It is key to have the data to make selections correctly.”
Summing up, Mr Baehr brought up the challenge of regulation and said, “Antifouling is critical, innovations are needed to ensure effective antifouling today and in the future.”
Mr Barnes added, “Regulations are not going away; they are going to get worse and tighter and make things more and more difficult. People are cleaning their vessels…it is interesting that with product selection a lot is based on cost or paint supplier recommendations, the cost of an effective fouling control system is not that expensive compared with what failure is going to cost.”
Poll results
Asked: How often do you perform underwater cleans during a five-year drydock cycle? 47% said one to two times during a five-year period, 29% said every one to two years, and 12% said every six months, while another 12% said cleaning is not required.
Asked: When specifying fouling control products do you either: 15% agreed with generally continue with the product/supplier that was used previously, 32% said the selection was based on cost, and 32% said they would take the paint supplier recommendation. 21% said they used third party advice.
Polled: How often does the eventual vessel trade (in terms of speed/activity/location) match the planned trade over a three or five-year drydock cycle? 38% most of the time and 37% said around 50:50. 19% said not often and 6% said never.
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