Alternative distillation configurations for bioethanol purification: Simulation, optimization and techno-economic assessment

Considering the economic and environmental importance of bioethanol fuel, this research evaluated the energetic, economic, qualitative and environmental aspects of the conventional purification system and also of two alternatives aimed at eliminating secondary flows and reducing costs associated with utilities and operation. Using the Aspen Plus software with the insertion of a relevant number of components of the industrial process, the purification of hydrated bioethanol was investigated, optimizing the specifications of the distillation set. The conventional process (C), composed of columns A and B and condensers RR1 and EE1E2, is subdivided into sections AA1D and BB1, respectively. In turn, the alternative systems (I & II) are similar to process C but without section D of column A; in the first system without the condensers R and the second including R1. These processes were satisfactorily developed and in compliance with the quality standards of specific Brazilian legislation. From the energy, economic and environmental point of view, the alternative processes lead to better results than the conventional system, especially alternative I, which provided reductions of 11.5 %, 6 % and 7.5 % in terms of steam consumption, operating costs , CO2 emissions, respectively. Although the application of the conventional process can be used to comply with the biofuel standard, simplified industrial plants, such as those proposed in the alternative processes, are sufficient and their use should be encouraged to extend the application to more types of products. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.

Automated summary

This research evaluates the energetic, economic, qualitative, and environmental aspects of bioethanol fuel purification systems and proposes two alternatives that can reduce costs and CO2 emissions. The alternative processes show better performance in terms of energy consumption, operating costs, and CO2 emissions reduction compared to the conventional system.