Page 17: of Marine News Magazine (July 2020)

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tion of methane slip to their ?eet’s decarbonization strategy. D F E E PUAL UEL NGINE MISSION ROFILES

Natural gas and other low-?ashpoint fuels, which are inher-

D ently low in sulfur, also can help owners to comply with the

UAL FUEL ENGINE CONVERSION

Speci?c fuel-supply systems are required to feed gas into SOx emissions limits of MARPOL Annex VI. They also offer dual-fuel engines at the right pressures and temperatures. The other SOx reductions and the sulphate portion of particulate main dual-fuel engine, the components of which are broadly matters because their sulfur content is typically less than 30 similar to conventional diesel-engine designs, also require key parts per million.

foundational engine components to operate in gas mode. Their NOx formation is linked to peak-combustion tem-

Furthermore, a diesel engine’s potential to be easily con- peratures, which are signi?cantly higher for diesel than they verted to dual fuel is an important consideration; for example, are for gas engines. Similarly, dual-fuel engines using the Otto if an owner is selecting a ‘Ready’ notation in preparation for process to burn natural gas have much lower NOx emissions converting the ship to burn natural gas at some point after than those using the diesel combustion process.

delivery of the vessel. ABS is continuing to develop a range of information and

The fundamental engine design of the MAN ME-GI is the initiatives to support the industry’s transition to low carbon same as its standard ME engines; ‘GI’ (gas injection) refers to operations.

all gas-related components that are necessary to allow an ME To help drive decarbonization strategies, ABS has published engine to operate on gas. As the ‘GI’ concept is an add-on to Setting the Course to Low Carbon Shipping: Pathways to the ME engine, the latter can be considered “gas ready”. Sustainable Shipping, the second in a series of industry out-

While Winterthur’s X-DF engine offers the same general look documents — the ?rst was published in June 2019 — design as their standard X engine (diesel), several other base to reference available carbon-reduction strategies and inform engine components are different, in addition to the added the shipping industry as it enters the uncharted waters of the gas-related components. 2030/2050 emissions challenge.

Crowley’s combination container/roll on-roll off (ConRo) ship El Coquí is one of two LNG-powered Commitment Class vessels providing shipping and logistics services between the U.S. mainland and Puerto Rico.

Crowley 17 www.marinelink.com MN