PM & Odor for Inland Navigation

Diesel particulate filter

Diesel particulate filters (DPF) consist of a ceramic structure of small channels that are alternately blocked, forcing exhaust gases to flow through the thin porous walls of the filter block. Diesel particles or soot get trapped in the porous walls of the diesel particle filters. If the temperature is high enough the soot will oxidize (burn) in a process called regeneration. After oxidation a small amount of ash remains on the filter wall. The majority of the ash comes from the lubricant oil, the rest from fuel and engine wear. 

Xeamos applies robust silicon carbide diesel particle filters with a proven long-term reliability in marine applications. Our particle filters reduce more than 97% of the particulate mass (PM) emissions from the engine.  

Diesel oxidation catalyst

Engines used in inland vessel normally run on ultra low sulphur fuel. With this fuel type a Diesel Oxidation Catalyst (DOC) can be applied. With a DOC installed in front of the DPF the regeneration temperature of the DPF is significantly reduced. This DOC also reduces the hydro-carbons and CO that are present in the exhaust gases. An additional catalytic coating can be applied on the DPF substrate in specific applications. The advantages of a DOC + DPF combination include a lower regeneration temperature than with a catalytically coated DPF and a reduced replacement cost. This results in a DPF system with the lowest cost of ownership (TCO).

Passive versus Active regeneration

The average exhaust temperature for many inland vessel engines is high enough to complete the regeneration of the DPF. If engineers are not certain that sufficient engine load can be maintained for longer periods of time it is better to choose an active regeneration system. In such cases regeneration is triggered by periodically raising the exhaust temperature. This process is automatically controlled by our control system. Xeamos applies diesel fuel burners or electric heaters that have been developed in-house.

Bypass valve

All Xeamos DPF systems are equipped with an automatic bypass valve, a safety device that limits back pressure in the exhaust system in the event of a system malfunction. Malfunctions can be caused by a failure of the active regeneration or by engine issues such as a faulty fuel injector or turbo. In case the bypass valves opens, an alarm is raised by the system controller to request for further investigation about the root cause of the intervention. The availability of the engine is ensured and the DPF system remains operational, with a limitation of soot reduction as a result.

Controls

The control of a diesel particle filter system with active regeneration is rather complex. The system is controlled and monitored by a state-of-the-art PLC-based control system with ParticulateControl Diagnostics (PCD). This means that the system is tamper-proof, meeting the requirements of the applicable legislation. Xeamos control systems are Class-approved and ensure a reliable and safe operation. The controller allows for easy communication or integration with the ship’s AMS through a MOD bus protocol or analogue I/O. Xeamos systems offer remote monitoring to provide support to chief engineers when required. All system values and signals as well as events, warnings and alarms are recorded and stored in a non-erasable log file. All logged data can be easily uploaded through a remote connection for further analysis and reporting by Xeamos engineers.

Reactor housing design

The reactor housing for our SCR and/or DPF systems is designed for the specified operating conditions. The pressure drop, flow uniformity and temperature distribution are accurately simulated using advanced CFD software. Mechanical stress calculations are made with our FEM software tools based on worst-case scenarios of maximum exhaust temperatures and pressures. The effect of low-cycle fatigue on the steel has to be taken into account to prevent premature failure of the system, especially with wet underwater exhausts. Different (stainless) steel types can be applied depending on the application and customer requirements.

Sound attenuation

Engine rooms in most vessels have limited space for an exhaust system, making the need to integrate emission reduction and silencers inevitable. Using our knowledge of acoustics, we offer solutions to integrate DPF, SCR and silencers according to your requirements. The sound attenuation is tuned to the engine characteristics to give an optimum reduction of the ignition frequencies and its harmonics, suppressing that annoying exhaust hum.

Relevant products

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MPAT ZS-FB ZS-EHS