First high-speed DF engine conversion
The development follows successful test bench runs on a Caterpillar 3618 engine. The diesel injection principle was maintained, allowing for unrestricted diesel operation if needed, while a multi-point gas admission system (based on type approved components in a double-walled configuration) was installed.
Engine management specialist Heinzmann supplied the dual-fuel system, including a Megasol 200 II Marine gas admission valve developed specifically for the project and Ariadne knock control. The system is managed by Heinzmann’s MVC 01-24 electric fuel injection controller which, combined with a WG-70 wastegate valve providing intelligent air path management, enabled engine operation on up to 90% gas.
Special attention was paid to the transient behaviour of the engine and the smooth and fast switch from diesel to gas operation. In case of gas system failure, the engine returns to diesel immediately.
Emission and reliability tests were successfully carried out by AVL, which oversaw engine design, followed by DNV GL approval testing. Heinzmann reported that fuel consumption was noticeably reduced by the engine efficiency raise in dual-fuel operation. With a fuel mix of 90% LNG and 10% marine gas oil, the engine produced emissions reductions of 30% for CO2, 50% for NOx and 90% for SOx.
All four engines of the Bencomo Express will be converted for dual-fuel operation next year, with further vessels to follow. The projected is co-financed by the European Commission under the GAINN4SHIP Innovation initiative.
