Exergy efficiency of thermochemical syngas-to-ethanol production plants
Abstract This work presents exergy analyses applied in four different conceptual second-generation ethanol production processes through a thermochemical route using catalysts based on Molybdenum (P-1), Copper (P-2), and Rhodium (P-3 and P-4), aiming to assess their exergetic efficiencies. The results show that the conceptual processes have satisfactory exergy efficiencies in both cases, when compared among themselves and when compared with other processes reported in literature. The processes’ efficiency for P-1, P-2, P-3 and P-4 were, respectively, 52.4%, 41.4%, 43.7% and 48.9%. The reactors were the sections in which exergy destruction was more significant, due to the exothermic reactions and mixing points (where streams with different temperatures were mixed). Such results show the potential of thermochemical ethanol production, besides opening the possibilities of process improvement. Graphic abstract