Underwater visibility is good in Rotterdam, and a large number of ships visit the port every day. SRN Group has a good working relationship with local parties, including the linesmen of KRVE. ‘That’s one of the reasons why we enjoy working in Rotterdam,’ says Manuella Maes.
In 2013, Pierre Klein, who used to work as project manager for a diving firm, founded SRN Group in Stabroek, Belgium. He was joined by his wife Manuella Maes, who has over 30 years of experience in the shipping sector. SRN Group handles diving operations and hull & propeller cleaning in West Africa and the sea ports of Belgium and the Netherlands. Many of the company’s cleaning jobs take place in the port of Rotterdam.
‘We have a fixed berth for our pontoon in Rotterdam, where we store our filtration and inspection systems in a container. Once we’ve sucked the fouling from the hull, we separate the water from the solid mass – meaning the only thing that flows back into the dock is clean water. We measure water quality before, during and after filtering.’
‘We basically clean every type of sea-going vessel around, but we mostly work on tankers. In the case of tankers, hull cleaning isn’t allowed while the vessel is loading or unloading. In Rotterdam, the tankers can moor out on the water, using dolphins. It’s ideal for our purposes. We can access the ship from all angles. Another pro is the good visibility under water and our pleasant collaboration with various local firms and the Port of Rotterdam Authority.’
‘Our cleaning robot uses soft bristles to remove the fouling. It’s operated via remote control and we can use it any hour of the day. We keep trying to improve it further. This is actually the third generation we’re working with right now. We’re currently developing a positioning system that will allow us to monitor our precise position along the ship’s hull. We’ve already tested the prototype, with good results. We can clean tankers that are moored out on the water in a single operation. In the case of container ships, we clean the vessel while it is loading or unloading. We clean the side of the hull that doesn’t line the quay. During its next visit to the terminal, the ship simply moors in the opposite direction, allowing us to clean the other side.’
‘Ship owners and shipping companies can save between 10% and 30% in fuel costs and the ships release less carbon into the atmosphere. What’s more, hull cleaning prevents exotic species – from Asia, for example – from establishing themselves in European waters. Many shipping companies have a dedicated optimisation department. These teams have a ship’s hull cleaned when they observe a drop in the vessel’s performance and an increase in fuel consumption. And ships need to keep a cleaning log for the inspectorate.’
‘The build-up rate depends on a variety of factors. The longer a ship remains in one place, the more fouling you get. You see a lot less build-up with container ships – which are often underway – than with tankers. But sunlight can play a part too, for example. Among other things, how long it takes to clean a vessel depends on the level of fouling and the ship’s dimensions. It will take us around 24 hours to clean a 200-metre tanker, for example.’