Ship engines generate different particle compositions than those known in land-based areas. Therefore, novel filter solutions need to be developed and tested. The accumulated soot is regularly burnt off in particle filters through regeneration. However, ash remains an inorganic residue in the filter.
To reduce particulate emissions, closed wall-flow filters are used in the land-based sector. The accumulated soot is burned off cyclically by thermal regeneration. In ship diesel engines, the proportion of organic and inorganic ash in the exhaust gas is many times higher, especially from the highly additive cylinder oils. Therefore, new filter systems must be tested. In particular, open-pored ceramic filters are to be tested. Diesel particulate filters (DPF) have proven their worth in minimizing particulate emissions in practice. The deposition of soot particles in the filter causes a pressure loss, which leads to fuel consumption disadvantages. To reduce this, the filtered particles are burned off cyclically. The non-oxidisable elements contained are not removed by the regeneration phases, so they remain unburned in the DPF and are partially removed via backwash processes. The result is a permanent ash layer that clogs the DPF over time and increases the back pressure during operation. Sources of ash particles in diesel exhaust are particles from the burnt lubricating oil, as a result of engine wear and corrosion processes. Particles resulting from the lubricating oil form the majority of the ash accumulated in the DPF. The largest share of oil consumption is accounted for by the consumption source of pistons/rings/cylinder tubes (~80%). In the sub-project "Ash loading of test vehicles on marine diesel engines", open-pore particle filters to be installed in the exhaust tract of a marine diesel engine (rated power: 960 kW) are loaded with ash. For this purpose, engine operation with diesel fuel and a marine circulating oil with corresponding TBN is intended. Therefore, there is a significant difference in the composition and quantity of the ash produced in the exhaust gas as it occurs in real maritime operations. In this sub-project, it is planned to use the main engine test bench in the Warnemünde maritime area to carry out foam filter loading. For this purpose, the test bench will be modified in the area of its exhaust gas routing. With the help of the analyzed filter samples, the ash ingress behaviour will then be described and parameterized. The mechanisms for changing the ash structure as a function of exhaust gas flow parameters will also be analyzed. The results will then be used to develop a physical simulation model to describe the ashing behaviour. The long-term goal is to predict the filters for different engine classes and the operating regime of the plants.