MAN B&W two-stroke engine operating on ammonia

One of the future fuel candidates receiving a growing global interest and likely to play a significant role in the decarbonisation is ammonia (NH3). Our aim with this paper is to share our current knowledge about ammonia as a potential long-term fuel for two-stroke marine engines and to give a new update on the development of an ammonia-based propulsion

Principles of dual-fuel operation During dual-fuel operation, the ammonia fuel supply to the engine comes from the storage tanks via the fuel supply system.
To maintain the required fuel conditions at the engine, a small portion of the ammonia fuel continuously recirculates to the FSS via the recirculation system.
When the engine is not in dual-fuel mode, the double block-and-bleed arrangements of the FVT depressurise and completely isolate the ammonia fuel systems inside the engine room from the ammonia fuel supply and return systems.
Before every start, the systems are pressurised with nitrogen to verify the tightness of the system.