HD HHI’s new ammonia dual-fuel containership design earns DNV and LR stamps of approval

October 30, 2024, by Ajsa Habibic

South Korean shipbuilder HD Hyundai Heavy Industries (HHI) has received approval in principle (AiP) from classification society DNV and signed a joint development project (JDP) for AiP with Lloyd’s Register (LR) for its new design of a 15,300 TEU ammonia dual-fuel containership.

DNV granted the approval to South Korean shipbuilder on October 29 as a result of a JDP aimed at addressing the challenges associated with using ammonia as a marine fuel, including an optimized ammonia tank design, advanced fire safety systems, enhanced ammonia release mitigation system and boil-off gas (BOG) handling systems.

According to DNV, under this project fuel pipe leakage scenarios were defined and quantitatively analyzed through gas dispersion analyses. It was confirmed that, with conventional systems, foreseeable small leakages occurring at connections within the ammonia piping system can form toxic areas with dangerous ammonia concentrations throughout the entire weather deck, highlighting the need for effective mitigation measures.

The result showed that hazardous areas were significantly reduced by the enhanced ammonia release mitigation system, enabling not only safer enclosed spaces but also safer working areas across the entire weather deck of the vessel.

Vidar Dolonen, DNV Regional Manager Korea and Japan, stated: “This AiP highlights the importance of safety in moving the maritime industry along the path to decarbonization. There are many aspects to building out zero carbon fuels in shipping, and it’s essential that we have them all in place for ammonia to truly establish itself in the marine fuel market. But with new technological solutions, alongside rigorous safety procedures, ammonia reach its full potential as one of the most promising green fuels. DNV is proud to support these advancements from HD HHI as we continue on this journey to an even more sustainable maritime industry.”

Under the agreement with LR, HHI has developed a twin skeg design for the 365-meter vessel with two small bore engines that are currently available on the market and ammonia fuel tanks positioned ahead of the engine room, far from the deckhouse, helping ensure safe fuel supply operations and better crew habitability.

It is said to be the first design to offer ammonia-powered dual fuel engines for ultra large containerships, as there is currently no large ammonia powered dual-fuel big bore engine technically available.

HHI and LR’s joint project aims to complete a full safety review that involves a feasibility assessment for ammonia fuel tanks constructed with low temperature steel and an evaluation of the structural integrity of the ship against sloshing loads. Additionally, it will review the fuel gas supply system, helping ensure safety and compatibility with ammonia.

LR said it had reviewed the design to ensure it meets applicable standards of safety and operational efficiency relating to the usage of ammonia as a marine fuel and provide technical advice for further design development. 