Mitsubishi Heavy Industries Marine Machinery & Equipment (MHI-MME), a Mitsubishi Heavy Industries (MHI) Group company, has begun demonstration testing for a methane oxidation catalyst system for LNG-fuelled vessels, being jointly developed with Daihatsu Infinearth.
The demonstration test, which began in May2025 in cooperation with Keys Bunkering West Japan, involves installing the demonstration equipment on the Keys-owned LNG bunkering vessel Keys Azalea, built by Mitsubishi Shipbuilding.
The catalyst system for the demonstration test oxidises unburned methane (methane slip) contained in the exhaust gas. Methane has a high greenhouse effect among GHGs, so the ability to suppress its emission is seen as a significant advantage of this system.
The methane oxidation catalyst system was developed with MHI-MME’s catalyst design and manufacturing technology at its core, combined with Mitsubishi Shipbuilding’s shipboard installation technology, and Daihatsu Infinearth’s engine optimisation technology. Since an initial methane oxidation rate of 70% or higher has been verified in the onshore engine test, the demonstration testing will be conducted continuously for one year.
MHI Group is making strategic efforts to strengthen its energy transition business. MHI-MME and Mitsubishi Shipbuilding are a part of this strategy, and amid the increasing urgency for global decarbonisation, will continue to work to reduce GHG emissions from ships, and contribute to the improvement of the environmental performance on a global scale.
Image: ‘Keys Azalea’, an LNG bunkering vessel equipped with the demonstration system (source: MHI)
