Exhaust gas aftertreatment system layout for hydrogen internal combustion engines

Hydrogen internal combustion engines are already at an advanced stage of development. They can provide a sustainable CO2 free power source for vehicles in areas where fuel cell or battery electric powertrains are not a suitable option. To achieve zero impact emissions from such engines, particular attention must be paid to reducing the nitrogen oxide (NOx) emissions, which also occur in a hydrogen-fueled internal combustion engine. In addition, substances such as ammonia (NH3) and nitrous oxide (N2O), which may result from the use of hydrogen, must be considered when developing zero impact emission concepts. This paper demonstrates how tailored exhaust gas aftertreatment systems in combination with optimized combustion systems and engine calibration can enable a virtually emission-free propulsion system with hydrogen as fuel.