Damen installs Marine NOX Reduction Systems on Van Oord’s Nexus

Cable layer benefits from Damen Group synergy in emissions reduction project.
Like Damen, Van Oord is a family business committed to sustainability. The company takes both a short and long-term view, considering the wider impact of its actions. Arising from this culture, is the company’s sustainability programme, S.E.A. – Sustainable Earth Actions.

Sustainable Earth Actions

The programme has a focus on four pillars: enhancing the energy transition, accelerating climate actions, empowering nature and communities, and achieving net zero emissions.

To reach its aims for the fourth pillar, Van Oord is committed to reducing its greenhouse gas emissions to within a 1.5 degree science-based limit in line with the EU Green Deal, meaning an intermediate target to reduce emissions from their own operations by 35% by 2030, against a 2023 base year. Further ambitions include achieving zero SOx emissions and an 80% reduction in NOx emissions by 2050 compared to 2019 levels. It was with this latter goal in mind that Van Oord reached out to Damen.

In 2014, Damen delivered the Nexus to Van Oord. A Damen Offshore Carrier with DP2 capabilities, the 122.68 x 27.45 metre vessel was built as a cable layer for the offshore wind industry and features a cable carousel with a capacity of over 5,000 tonnes.

The offshore wind sector is itself increasingly focused on ensuring sustainable operations. This includes the reduction of NOX emissions close to shore where Nexus is working. As such, the vessel suggested its potential for Van Oord to work towards its goals.

Proven system

In 2015 in preparation for the forthcoming IMO Tier III regulations, Damen developed its Marine NOX Reduction System. This advanced system is suited to multiple engine types and reduces emissions with selective catalytic reduction (SCR) technology.

It works by applying a catalyst to react with injected urea, chemically cleansing NOx from the vessel’s exhaust emissions by up to 80%. The SCR is a modular system that is easily installed to either newbuild vessels or as a retrofit.

Van Oord required Damen to install five Marine NOx Reduction Systems – one for each of the Nexus’ MAK engines. The type of engine required Damen to carry out some adaptation to its standard solution, says Damen Program Manager Sustainable Propulsion André de Bie.

“The MAK installations use a medium space engine with lower revolutions than the engines with which the SCR is typically used. Plus, the pulse is higher, which required some strengthening of the silencers. Beyond that, however, it’s the same proven solution we have previously installed on tugs, workboats, yachts and inland waterway vessels.”

Solutions with synergy

The Nexus project, André says, drew upon a wide range of skills from multiple teams throughout the Damen Shipyards Group.

“The Nexus installation was a great example of the synergy to be found within Damen. The Marine NOx Reduction System is produced at our headquarters in Gorinchem, the Netherlands, the engineering was performed by Damen Engineering Gdansk in Poland, and the project executed at Damen Shiprepair Amsterdam (DSAm). With all these skills in-house, we are able to offer our clients a comprehensive solution.”

Along with Damen’s familiarity with the vessel as the original builder, this holistic approach was one of Van Oord’s reasons for selecting Damen to carry out the project. Hein Leemhuis, Van Oord’s Manager Projects Fleet says, “We chose Damen as they were able to offer us a one-stop-shop solution, taking care of the entire project, which represented a considerable boost in efficiency.”

Turning down the volume

There was a further reason behind Van Oord’s selection of Damen’s Marine NOx Reduction System – the SCR’s relatively compact nature.

“Damen’s system combines the damper and scrubber in a single unit,” explains Hein. “This ensures that the system is lower in volume. With an existing ship that has not been built with an SCR system in mind, there is a minimum of space available, so a system such as this is perfect for a retrofit project."

The work scope

The installation of the SCRs required Damen to carry out a complete refurbishment on the Nexus’ funnel, replacing the conventional steel with stainless steel to withstand the effects of urea. The yard also installed an additional platform in the engine room where the urea dosing units were placed.

An existing tank was blasted and treated, repurposing it for the storage of urea. Other tasks included pipework and the installation of lines, running from the tank to the funnel. At the same time the Nexus was in dock, DSAm also carried out maintenance work to her thrusters.

With the SCRs installed, it was time for independent measurement and validation. This was an important phase, as the Nexus was required to be ready, with her reduced NOX profile, in time for a project commencing in October.

Going forward

Fortunately, all went well and the vessel was able to leave the yard ready for the next job – and for a reduced emissions future.

“The project was not without its challenges,” says Hein. “Particularly given the relatively tight timeframe we were working to. However, what’s important is how these challenges are approached. Working together, we were able to solve any issues that arose. We were very happy with Damen’s performance on the project.”

André agreed that the project represents a good collaboration, saying, “There is a good match in the culture and mentality between Damen and Van Oord – we both want to go forward. When you’re both looking in the same direction, things are easier. As a result, there has been a very pleasant cooperation that has helped to ensure such a positive result.”