Removal of Nitrogen Based Pollutants From the AmmoniaDrive Exhaust

As the shipping industry needs to become greener, it has to move away from fossil fuels. For deep-sea shipping, ammonia is marked as a high potential fuel. The AmmoniaDrive concept feeds the anode-off gas from a Solid Oxide Fuel Cell (SOFC) and additional ammonia into an Internal Combustion Engine (ICE). The exhaust gas coming from the ICE can contain relatively large amounts of NOx, NH3 and N2O. This research focuses on reducing all these substances using Selective Catalytic Reduction (SCR) in steady-state conditions. A 1-d single-channel model is used to model a Vanadium, Iron and Copper catalyst. The levels of pollutants entering the atmosphere are compared to the current legislation for ships, where NOx emissions are limited. Furthermore, new legislation is proposed that also limits the NH3 and N2O emissions of the powerplant. Meeting these limits is much more complicated than meeting the current legislation. The presence of N2O in the exhaust can be problematic as only the Fe catalyst can reduce N2O with temperatures above 350/400 degC. The Cu based SCR has the highest potential for AmmoniaDrive as it can meet the newly proposed limits with exhaust temperatures below 200 degC, this allows for an efficient driveline.Marine Technology | Marine Engineerin