Process Intensification for Ammonia Synthesis in Multibed Reactors with Fe-Wustite and Ru/C Catalysts

An ammonia synthesis loop is designed using two different catalysts, namely, a Fe-based one from a wustite precursor and a Ru/C sample. Previously established kinetic models have been used and implemented in a process simulator to investigate different feeding and quenching arrangements. A different array of series and parallel reactive stages is then proposed and optimal conditions for the feeding strategy and catalyst loading are discussed. It is found that loading the last reacting stages with Ru/C (instead of Fe-wustite) always improved the ammonia yield when other conditions were fixed. Different feed-splitting, intercooling, and quenching options were tried to verify their effect on the heat duty of the reactor and the interplay between this aspect and the ammonia product fraction. Adopting mixed catalyst configuration allowed considerable energy savings both as lower duty for the recycle loop compressor and decreased heat exchange needs, boosting process intensification as one of the primary challenges for this reaction.