Downstream process of sustainable aviation fuel using diabatic distillation

To reduce the production cost of biojet, a sustainable aviation fuel, an energy-efficient separation process is proposed, and its performance was evaluated in terms of technical, economic, and environmental aspects. Using diabatic distillation, the energy recovered from the condenser and rectifying section of the column trays was recycled to the reboiler and stripping section. Compared with the conventional feed-preheated process, the proposed process consumes 22% less energy. While the thermodynamic efficiency of the 1st column of the proposed process was slightly higher than that of the conventional process, the 2nd column operated at a lower efficiency owing to the increased operating pressure applied for heat recovery. The utility cost of the proposed process was reduced by 20%, and its estimated eco-score was on average 22% lower than those of the conventional process. Compared to previously studied thermally coupled processes, 30% less utilities were required to produce the same amount of biojet, using a lower total number of trays. Graphical abstract