Shipowners looking to install marine exhaust gas cleaning systems as way of meeting global sulphur cap requirements need to ensure that manufacturers, shipyards and installers are using quality, high-end materials, members of the Clean Shipping Alliance (CSA) 2020 advised.
Scrubbers have been identified as one of the top choices for complying with the sulphur cap, especially when considering the Return on Invest (RoI). However, numerous concerns have been raised when it comes to the very maintenance of scrubbers and the risk of potential malfunctions, especially when ships are on the open seas.
According to the collective experience of the association members, the quality of materials and coatings used is the most important factor in optimizing EGCS safety and averting any corrosion problems during operation.
“Risks can be mitigated by investing in quality materials, established suppliers and experienced installers, and by optimizing machinery space layouts,” said Arne Hubregtse, Executive Board Member, Spliethoff.
“We have installations onboard about 50 vessels in the Spliethoff fleet and to date we have not experienced any corrosion or other significant issues through operating these systems. In addition to the specification of quality materials we recommend experienced installers with good supervision during the installation process.”
Echoing Spliethoff’s experience is Wallenius Wilhelmsen, a shipowner operating a fleet of more than 130 deep-sea ro-ro vessels.
Roger Strevens, Vice President, Global Sustainability, Wallenius Wilhelmsen, said: “While EGCS failure is not impossible, just as it is with any machinery, we believe we have minimized the risk – particularly of early-onset severe failure – by being very judicious in how we specify the systems and through being particular in who we are getting them from. If you buy cheap, you’ll pay twice!”
Wallenius Wilhelmsen installed its first EGCS in 2014 knowing that, like any first-of-type-installation, there would be the inevitable teething troubles. “We learned a lot from that first installation. The experience proved invaluable to subsequent installations,” added Strevens.
Over 200 exhaust gas cleaning systems aboard 83 ships operating under the Carnival Corporation umbrella have also been largely reliable, according to Mike Kaczmarek, Sr. Vice-President Marine Technology, Carnival Corp, who cited over 90% current system availability.
“There are a few things to be aware of and, for example, we do recommend that the upper bellows (expansion joints) above the EGCS tower are replaced with a design using upgraded alloys during the installation process. This can help prevent any subsequent corrosion. The selection of quality materials is important,” Kaczmarek said.
Grimaldi Group, which operates four different EGCS over 50 ships reports more than 90% reliability, also believes the bellows require special attention.
“The expansion bellows after the scrubber and the exhaust gas line can create problems. It is important to use high quality steel or alloys and make sure anti-corrosion coatings have been properly applied to the discharge outlet. Good specification and subcontractor selection can prevent problems later,” Dario Bocchetti, Head of the Grimaldi Group Corporate Energy Saving & Innovation, said.