The technical group Wärtsilä and AP Moller – Maersk (Maersk) have developed a means of preventing corrosion in scrubber discharge pipes.

Wärtsilä/Maersk’s in-pipe solutions are designed to solve corrosion problems associated with the discharge of wash water in open-loop scrubbers for long-term protection.

The majority of the estimated 5,000 scrubber systems installed across the world’s fleet are open-loop configurations. This system cleans the sulfur oxides in the exhaust gas with seawater, cleans the used water, and discharges it into the sea.

According to IMO guidelines, the pH of wash water from flue gas cleaning systems (commonly called scrubbers) must be at least 6.5. However, the pH of scrubber wash water is typically acidic before it is diluted with seawater, creating a risk of structural corrosion, especially for mild steel drains.

With its new ‘pipe-in-pipe’ solution, Wärtsilä leaves the original outboard pipe in place while the new glass-reinforced epoxy (GRE) pipe is inserted, without the need for metal cutting or welding. said it can.

Then insert the SMO steel sleeve between the new GRE pipe and the existing steel pipe and fix the GRE pipe with glue.

This ‘pipe-in-pipe’ solution has a smaller impact on the inner diameter of the pipe, so according to the technical group, it is best suited for outboard pipes with a diameter greater than 300 mm.

“This is a long-term solution that we can always plan for, even if corrosion has not yet occurred,” said William Winters, Managing Director of Wärtsilä Underwater Services.

“Component pipes can be prepared and stored on board or at engineering facilities during scheduled dry docks or port calls, or as needed, on the water and in operation using cofferdams at a convenient time and place. .

“This in-service repair will provide significant overall savings to shipowners, allowing them to keep their vessels operational.”

Jorn Kahle, Senior Lead Specialist at Maersk, said:

“Additionally, taking a vessel out of service is very expensive. Minimizing these disruptions and costs is one of the main drivers for the development of this pipe-in-pipe concept by Wärtsilä Underwater Services.

“We are pleased to offer this unique, cost-effective service to any vessel with scrubbers from any manufacturer.”

Installation is done by Wärtsilä Underwater Services and most repairs are completed within 2 days.

Last week, Wärtsilä Voyage, part of Wärtsilä, signed a five-year framework agreement with Associated British Ports (ABP).

A deal signed with ABP, one of the UK’s leading port groups, will digitize operations at 21 ports.