The most important change compared to the previous engines for IMO II is the new mtu exhaust gas aftertreatment, the core component of which is an SCR system in which nitrogen oxide emissions are reduced by 75 percent compared to the IMO II limits.
It is an actively controlled system in which the emissions upstream and downstream of the SCR system are continuously measured. This ensures optimum and compliant operation of the exhaust gas aftertreatment system and a minimum dosage of the required reducing agent. Rolls-Royce offers its customers maximum installation flexibility: the system can be installed both horizontally and vertically and can therefore be adapted to a wide variety of ship designs and layouts.
The system itself is already designed to be shock-proof for military applications. If required, the system is available with bypass in order to maintain safe engine operation and unrestricted propulsion power even under extreme shock requirements and long low-load periods.
With the approval of mtu Series 1163 and 8000 engines for HVO and other DIN EN15940 fuels, they can replace conventional diesel fuel made from fossil oil without any modifications to the engines.