Addressing Methane Slip in LNG Operations: Testing Underway for Onboard System

The release of unburnt methane poses a significant challenge for LNG operations, as environmentalists emphasize its potent impact as a greenhouse gas emission. In response to this pressing issue, testing is now underway for an innovative onboard system installed on an in-service LNG bunker vessel.

The LNG industry has made strides in reducing methane emissions with the latest generation of marine engines. However, researchers continue to explore solutions to further mitigate emissions and enhance the long-term sustainability of LNG.

Collaborating with Daihatsu Infinearth Mfg. Co., Japan’s Mitsubishi Heavy Industries Marine Machinery & Equipment Co. has developed a methane oxidation catalyst system. Initial tests on shore have shown promising results, with a verified methane oxidation rate of 70 percent or higher.

The next phase of testing involves installing the system on the KEYS Azalea, a 2,352 dwt LNG bunkering vessel built in 2024 by Mitsubishi Shipbuilding. This vessel plays a crucial role in providing domestic coastal transport of LNG and bunkering services for oceangoing ships in the Kyushu and Setouchi regions.

The catalyst system works by oxidizing slip methane present in marine engine exhaust gases. Through a chemical reaction, methane is converted into carbon dioxide and water, thereby reducing harmful emissions.

Over the next year, continuous demonstration testing will be conducted as part of MHI Group’s strategic efforts to bolster its energy transition business. With a focus on reducing greenhouse gas emissions from marine vessels, Mitsubishi Heavy Industries aims to enhance the environmental performance of ships globally.