The aim of the project is to reduce ship-based emissions through optimized and extended exhaust gas cleaning to protect the atmospheric and maritime environment. The focus is on the emission of fine particles smaller than 2.5 µm (PM2.5). Furthermore, the pollution by pollutants due to incomplete fuel combustion will be investigated. A change in the emission composition can be expected when the new IMO regulations (sulphur content in fuel <  0.5 % or use of an exhaust gas cleaning system) come into force. When using an exhaust gas cleaning system (gas scrubbing), the extremely small particles that are hardly reduced by it are particularly problematic. In addition to the aerosols, the washing water is also subject to only minor regulation in this respect, so that pollutant-laden particles can enter the marine environment. Using an exhaust gas scrubber with downstream particle filter and washing water treatment, additional highly sensitive process and emission measurement technology and simulations, we aim to optimise the individual process steps within a project period of 3 years, which is reflected in an overall reduction in emissions as follows:

• A highly efficient separation of 90% of both the total particle mass and the particle fraction 2.5 - 0.1 µm
• Reduction of the number of microparticles (1.0-01 µm) by 90%
• Compliance with environmental quality standards in the field of water policy (2008/105/EC)
• Turbidity value of the washing water <  25 NTU

The IOW monitors the washing water analysis of the particles for organic pollutants (e.g. PAHs), metal residues, elementary composition and ecotoxicological hazard potential. Using highly sensitive measuring instruments, an evaluation of the effects of the use of scrubbers following the entry into force of the IMO regulations on the reduction of SOx emissions will provide information on their environmentally relevant consequences.