Exergy Load Distribution Analysis Applied to the Dehydration of Ethanol by Extractive Distillation
Camilo Andrés Guerrero-Martin,
Juan Sebastián Fernández-Ramírez,
Jaime Eduardo Arturo-Calvache,
Harvey Andrés Milquez-Sanabria,
Fernando Antonio da Silva Fernandes,
Vando José Costa Gomes,
Wanessa Lima e Silva,
Emanuele Dutra Valente Duarte,
Laura Estefanía Guerrero-Martin,
Elizabete Fernandes Lucas
Affiliations
Camilo Andrés Guerrero-Martin
LOTEP—Laboratório de Operações e Tecnologias Energéticas Aplicadas na Indústria do Petróleo, Faculty of Petroleum Engineering, Federal University of Pará, Salinópolis 66075-110, Brazil
Juan Sebastián Fernández-Ramírez
Departamento de Ingeniería Química y Ambiental, Universidad Nacional de Colombia, Bogotá 111321, Colombia
Jaime Eduardo Arturo-Calvache
Departamento de Ingeniería Química y Ambiental, Fundación Universidad de América, Bogotá 111221, Colombia
Harvey Andrés Milquez-Sanabria
Departamento de Ingeniería Química y Ambiental, Fundación Universidad de América, Bogotá 111221, Colombia
Fernando Antonio da Silva Fernandes
Department of Engineering, Federal University of Pará—Campus Salinópolis, Rua Raimundo Santana Cruz, 9 S/N, Bairro São Tomé, Salinópolis 68721-000, Brazil
Vando José Costa Gomes
LOTEP—Laboratório de Operações e Tecnologias Energéticas Aplicadas na Indústria do Petróleo, Faculty of Petroleum Engineering, Federal University of Pará, Salinópolis 66075-110, Brazil
Wanessa Lima e Silva
LOTEP—Laboratório de Operações e Tecnologias Energéticas Aplicadas na Indústria do Petróleo, Faculty of Petroleum Engineering, Federal University of Pará, Salinópolis 66075-110, Brazil
Emanuele Dutra Valente Duarte
LOTEP—Laboratório de Operações e Tecnologias Energéticas Aplicadas na Indústria do Petróleo, Faculty of Petroleum Engineering, Federal University of Pará, Salinópolis 66075-110, Brazil
Laura Estefanía Guerrero-Martin
LOTEP—Laboratório de Operações e Tecnologias Energéticas Aplicadas na Indústria do Petróleo, Faculty of Petroleum Engineering, Federal University of Pará, Salinópolis 66075-110, Brazil
Elizabete Fernandes Lucas
Metallurgical and Materials Engineering Program/COPPE/LADPOL, Federal University of Rio de Janeiro, Av. Horácio Macedo, 2030, Bloco F, Rio de Janeiro 21941-598, Brazil
This study presents the analysis of the exergy load distribution in a separation process by extractive distillation for ethanol dehydration. The methodology carried out is divided into three parts: the calculation of the flow exergy considering the physical and chemical exergies of the distillation process; the calculation of the primary and transformed exergy contributions considering the consumed exergy; and finally, the overall process efficiency, which shows the real percentage of energy being used in the process. The simulation of an extractive distillation separation system is carried out using Aspen Plus®, from Aspen Tech Version 9. In general, heat transfer processes (heating or cooling) are the ones that generate the greatest exegetic destruction, which is why they must be the operations that must be optimized. As a result of our case study, the local exergy efficiency of the extractive distillation column is 13.80%, which is the operation with the greatest energy loss, and the overall exergy efficiency of the separation system is 30.67%. Then, in order to increase exergy efficiency, a sensitivity analysis is performed with the variation of the azeotrope feed, number of stages, reflux ratio, and solvent feed variation on ethanol purity to reach an overall efficiency of 33.53%. The purity of ethanol is classified as higher than that of the specified, 99.65%.
