Mitsubishi Heavy Industries Marine Machinery & Equipment Co., Ltd. and Mitsubishi Shipbuilding Co., Ltd., both part of the Mitsubishi Heavy Industries Group, have received Approval in Principle (AiP) from Nippon Kaiji Kyokai for the basic design of a methane oxidation catalyst system for marine LNG-fueled engines. The system, developed in collaboration with Daihatsu Infinearth Mfg. Co., Ltd., was presented at Sea Japan 2026.
The methane oxidation catalyst system aims to reduce methane slip, or unburned methane, in the exhaust gas of marine engines. Methane, a potent greenhouse gas, presents significant environmental challenges, and the system's ability to reduce emissions represents a notable advancement. The system combines MHI-MME's catalyst technology, Mitsubishi Shipbuilding's installation expertise, and Daihatsu Infinearth's engine optimization skills.
Verification testing is underway with Nippon Yusen Kabushiki Kaisha, using a full-scale demonstrator on the KEYS Azalea, an LNG bunkering vessel operated by KEYS Bunkering West Japan Ltd. Initial tests have shown a methane oxidation rate exceeding 90%, confirming the system's expected performance.
Following the AiP acquisition and successful initial testing, the companies plan to expedite the system's development toward commercialization. This initiative aligns with MHI Group's broader strategy to enhance its energy transition business and contribute to global decarbonization efforts, particularly in the maritime sector.