Japan Engine Corporation (J-Eng), the joint venture company between Mitsubishi and Kobe Diesel, has announced that the first 6UEC35LSJ diesel engine for MGO-mono-fuelled/stratified water injection has been completed, and will be delivered to Onomichi Dockyard as the main engine of a 17,500 dwt costal vessel for MOL Drybulk.
The engine claims a fuel oil consumption over the conventional same class engine of about 5% less by applying the company’s stratified water injection system, and can comply with EEDI phase 3 requirements. Using MGO as the sole fuel, the fuel oil supply system can be simpler than heavy fuel usage by omitting the fuel heating system. Fuel oil change-over procedure from heavy fuel to MGO when entering port is not required. MGO is said to have stable properties and it is expected that maintenance interval of combustion chamber components can be extended through increase of reliability and reduction of crew’s burden.
The stratified injection system is a technology to inject two different liquids from a single injector. In the case of this engine, MGO and water are injected to achieve lower fuel consumption and NOx reduction simultaneously. In addition, in the shop test running, 100% bio fuel with stratified water injection operation, namely carbon neutral operation, was demonstrated and verified for the first time on a commercial engine.
The MGO-mono-fuelled/water stratified injection engine is aimed at medium/small size vessels, as a solution to reduce initial investment and to save installation space for fuel tank(s). At the same time, EEDI (reduction of GHG emissions) is also reduced to contribute to CSR (corporate social responsibility).
Three 6UEC35LSJ engines have been ordered so far, and the company is in discussions regarding further contracts.
The stratified injection system enables a selection of fuels – not only bio-fuels, which have been verified on the first example – but also LPG, methanol and other low-flashpoint fuels. The same technology is at the core of an ammonia-fuelled engine, which is under development, subsidised by Japan’s Green Innovation Fund for future drastic reduction of GHG emissions.