MPAT-S system

Marine Propulsion After Treatment for sulphur-containing fuels (DMA and DMX)

This system has been specifically developed for use on engines that run on sulphur-containing fuel and/or for countries where no ultra-low sulphur fuel is available. The maximum allowed quantity of sulphur in the fuel is 2000 ppm of 0.2% within this context.

The MPAT system is an all-in-one combination of SCR DeNox and a DPF (diesel particulate filter) system with all related components. The system replaces a silencer and will provide sound attenuation between 35 and 40 dB(A) as standard. The MPAT-S is the perfect combination system for vessels that have to comply with the IMO Tier III (IMO T3) legislation. 



The MPAT-S system can only be supplied as a Compact model. We can offer customised solutions for very narrow engine rooms.

The system can also be supplied in phases so that you can spread your investment costs:

  1. MPAT unit with dummy elements for SCR and diesel particulate filters.
    This option can be installed instead of a silencer and is only in preparation.
  2. MPAT-SCR prepared for later installation of diesel particulate filters.
    When compared to (1), here the SCR system has been installed including SCR catalyst, an injector, a pump and dosing set and a controller. Dummy blocks have been installed at the location of the diesel particulate filters.  
  3. MPAT-SCR+DPF prepared for active regeneration.
    When compared to (2), here the oxidation catalyst and diesel particulate filters have been installed, but without active regeneration. This is only possible with regard to specific engine types and sailing profiles where the average exhaust gas temperature is sufficiently high.
  4. MPAT-SCR+DPF+AR, full system.
    This is the MPAT system in the most extensive model with an SCR system and diesel particulate filter including active regeneration. The diesel particulate filters can regenerate with regard to every sailing profile.


MPAT-S system overview


Examples of deliverable options are:

  • Stainless steel unit
  • Intake and exhaust at an alternative position
  • Deviating diesel particulate filter or SCR catalyst types for special sailing profiles or engine models
  • Engine load signal analogue instead of J1939 
  • External communication through Mod or CAN bus.


SCR system

Xeamos SCR systems operate using a urea solution to reduce harmful nitrogen oxides (NOx). Reductions of more than 95% are possible. Xeamos SCR systems work with reliable compressed air atomization and are suitable for a 32.5% (Ad-blue of AUS32) or 40% (AUS40) urea solution.  

More information can be found on the Tech Talk page.


Diesel particulate filter system:

In contrast to the standard MPAT that is suitable for EN 590, we use catalytically coated diesel particulate filters with regard to this system. This coating ensures that the caught particulates oxidise at a lower temperature with oxygen. Without this coating, particulates would, after all, only burn at approximately 600 °C. The type of catalytic coating is aligned with the engine type, load profile and the required hydrocarbon reduction by our engineers.  

Since a higher temperature is required for this diesel particulate filter type for regeneration when compared to the standard MPAT system, it is always provided with an SFB burner system. This system ensures that the exhaust gases are regularly heated so that the diesel particulate filter stays clean.  

More information can be found on the Tech Talk page.


Achievable emission reductions

Nitrogen oxides NOx up to 95%*
Hydrocarbons HC up to 80%
Carbon monoxide CO  up to 80% 
Fine dust or particulates  PM10  > 95%
Noise    ca. 40 dB(A) 

*  The actual reduction will depend on the set value for the outgoing NOx. The outgoing NOx emissions amount to approx. 2 g/kWh depending on the speed in accordance with the IMO III emission criteria. This value is achieved at a reduction of 60-80%.

More information on emission technology can be found on the Tech Talk page


MPAT-S diagram



Contact Xeamos for more information about this system.