NYK of Japan has conducted its first onboard measurement in a demonstration test of a methane oxidation catalyst system for marine engines fuelled by LNG.
The demonstration test is being carried out in collaboration with Mitsubishi Heavy Industries Marine Machinery & Equipment (MHI-MME), Mitsubishi Shipbuilding (MHIMSB), and Daihatsu Infinearth (IE).
The catalyst system has been installed on the LNG bunker vessel Keys Azalea, which supplies fuel to LNG-fuelled ships. The vessel is owned by Keys Bunkering West Japan and managed by Taiheiyo Enkai Kisen, an NYK Group company.
In LNG-fuelled marine engines, methane slip can occur when some of the methane in the fuel does not burn completely and escapes into the atmosphere. Because methane has a higher global warming potential than CO2, reducing methane slip is an important technical challenge for decarbonising maritime transport. The methane oxidation catalyst system reduces these emissions by oxidising methane in the exhaust gas produced by LNG-fuelled engines.
The catalyst system was developed by integrating each partner’s specialist technological expertise: MHI-MME’s design and manufacturing of catalyst systems, MHIMSB’s shipbuilding, and IE’s engine optimisation.
In prior tests on land-based engines, the system demonstrated an initial methane oxidation rate of at least 70% (i.e. at least 70% methane removal). In the latest onboard measurement during this demonstration, the system achieved over 90% methane oxidation as a standalone exhaust treatment unit.
As part of this demonstration, a full-scale prototype has been installed onboard Keys Azalea for a one-year trial period. Operating mainly in the Kyushu and Seto Inland Sea regions, the vessel is now undergoing performance verification under actual operating conditions to support practical application.
The NYK Group says it is actively promoting the use of next-generation fuels, including LNG, to achieve decarbonisation in maritime transport, and continues working to reduce GHG emissions from vessels and minimise environmental impact.
LNG bunker vessel ‘Keys Azalea’ (source: NYK Group)
