Comprehensive Evaluation of Side-Absorber Distillation Column Performance in Ethanol Extractive Dehydration

Document Type : Research Article

Authors

1 Department of Chemical Engineering, Qu.C., Islamic Azad University, Quchan, Iran

2 Department of Chemical Engineering, Ma.C., Islamic Azad University, Mashhad, Iran

Abstract

A side-absorber distillation column (SADC) model was used for ethanol extractive dehydration (EED) with ethylene glycol (EG) as the solvent for the first time. The model performance was evaluated in terms of product purity, energy consumption rate, and the amount of solvent used. Initially, the system behavior was analyzed from a thermodynamic point of view. Then, the process was simulated, and the effect of all operational and design variables was separately and simultaneously evaluated through sensitivity analysis. By determining the optimal value of each variable, the SADC model was optimized. Using the optimized structure, ethanol with a molar purity of 99.8% and a specific energy consumption rate of 0.325 kWh/kg was extracted. Then, the performance of the SADC structure was operationally compared with classical two-column (CTC) and dividing wall column (DWC) configurations. In addition to maintaining high purity, the SADC model can reduce the reboiler heat duty by 37% and 30%, respectively, compared to the CTC and DWC structures. The amount of solvent consumed in the SADC structure was also reduced by 26.3% compared to the other two configurations. On the other hand, the SADC model is simpler and structurally smaller than other models, and it imposes less investment and operational costs.   

Keywords

References

[1] Soares, R.B., Pessoa, F.L.P., Mendes, M.F., 2015. Dehydration of ethanol with different salts in a packed distillation column, Process Safety and Environmental Protection, 93, 147-153. https://doi.org/10.1016/j.psep.2014.02.012
[2] Gil, I.D., Gomez, J.M., Rodriguez, G., 2012. Control of an extractive distillation process to dehydrate ethanol using glycerol as entrainer, Computers and Chemical Engineering, 39, 129– 142. https://doi.org/10.1016/j.compchemeng.2012.01.006
[3] Kiss, A.A., Suszwalak, DJ.P.C., 2012. Enhannced bioethanol dehydration by extractive and azeotropic distillation in dividing-wall column, Separation and Purification Technology, 86, 70-78. https://doi.org/10.1016/j.seppur.2011.10.022
[4] Vazquez-Ojeda, M., Segovia-Hernandez, J.G., Hernandez, S., Hernandez-Aguirre, A., Kiss, A.A., 2013. Design and optimization of an ethanol dehydration process using stochastic methods, Separation and Purification Technology, 105, 90–97. https://doi.org/10.1016/j.seppur.2012.12.002
[5] Granjo, J.F.O., Nunes, D.S., Duarte, B.P.M., Oliveira, N.M.C., 2020. A comparison of process alternatives for energy-efficient bioethanol downstream processing, Separation and Purification Technology, 238, 116414. https://doi.org/10.1016/j.seppur.2019.116414
[6] Polyakova, M., Skiborowski, M., 2025. Next-generation pervaporation-assisted distillation: Recent advances in process intensification, Chemical Engineering and Processing - Process Intensification, 216, 110416. https://doi.org/10.1016/j.cep.2025.110416
[7] Figueroa, J.E.J., Rodrigues, M.I., Maciel, M.R.W., 2015. Sequential strategy of experimental design I: Optimization of extractive distillation process of ethanol–water using [bmim][N(CN)2] as entrainer, Chemical Engineering and Processing: Process Intensification, 93, 56–60. https://doi.org/10.1016/j.cep.2015.04.008
[8] Ma, Sh., Hou, Y., Sun, Y., Li, J., Li, Y., Sun, L., 2017. Simulation and experiment for ethanol dehydration using low transition temperature mixtures (LTTMs) as entrainers, Chemical Engineering & Processing: Process Intensification, 121, 71–80. https://doi.org/10.1016/j.cep.2017.08.009
[9] Ramos, W.B., Figueiredo, M.F. and Brito, R.P., 2014. Optimization of Extractive Distillation Process with a Single Column for Anhydrous Ethanol Production, Proceedings of the 24th European Symposium on Computer Aided Process Engineering – ESCAPE 24, Budapest, Hungary, June 15-18.
[10] de Figueiredo, M.F., Guedes, B.P., de Araujo, J.M.M., Vasconcelos, L.G.S., Brito, R.P., 2011. Optimal design of extractive distillation columns-A systematic procedure using a process simulator, Chemical Engineering Research and Design, 89 (3), 341–346. https://doi.org/10.1016/j.cherd.2010.06.011
[11] Kiss, A.A., Ignat, R.M. and Bildea, C.S., 2014. Optimal Extractive Distillation Process for Bioethanol Dehydration, Proceedings of the 24th European Symposium on Computer Aided Process Engineering – ESCAPE 24, Budapest, Hungary, June 15-18.
[12] Alvarez, V.H., Alijo, P., Serrao, D., Filho, R.M., Aznar, M., Mattedi, S., 2009. Production of Anhydrous Ethanol by Extractive Distillation of Diluted Alcoholic Solutions with Ionic Liquids, Computer Aided Chemical Engineering, 27, 1137-1142. https://doi.org/10.1016/S1570-7946(09)70410-9
[13] Zhu, Zh., Ri, Y., Li, M., Jia, H., Wang, Y., Wang, Y., 2016. Extractive distillation for ethanol dehydration using imidazolium-based ionic liquids as solvents, Chemical Engineering and Processing: Process Intensification, 109, 190–198. https://doi.org/10.1016/j.cep.2016.09.009
[14] Miranda, N.T., Maciel Filho, R., Wolf Maciel, M.R., 2020. Comparison of Complete Extractive and Azeotropic Distillation Processes for Anhydrous Ethanol Production Using Aspen Plus™ Simulator, Chemical Engineering Transactions, 80, 43-48. https://doi.org/10.3303/CET2080008
[15] Imad, M.,  Castro-Muñoz, R., 2023. Ongoing Progress on Pervaporation Membranes for Ethanol Separation, Membranes, 13(10), 848. https://doi.org/10.3390/membranes13100848
[16] An, Y., Li, W., Li, Y., Huang, Sh., Ma, J., Shen, Ch., Xu, Ch., 2015. Design/Optimization of Energy-Saving Extractive Distillation Process by Combining Preconcentration Column and Extractive Distillation Column, Chemical Engineering Science, 135, 166-178. https://doi.org/10.1016/j.ces.2015.05.003
[17] Quijada-Maldonado, E., Aelmans, T.A.M., Meindersma, G.W., de Haan, A.B., 2013. Pilot plant validation of a rate-based extractive distillation model for water–ethanol separation with the ionic liquid [emim][DCA] as solvent, Chemical Engineering Journal, 223, 287–297. https://doi.org/10.1016/j.cej.2013.02.111
[18] Quijada-Maldonado, E., Meindersma, G.W., de Haan, A.B., 2014. Ionic liquid effects on mass transfer efficiency in extractive distillationof water–ethanol mixtures, Computers and Chemical Engineering, 71, 210–219. https://doi.org/10.1016/j.compchemeng.2014.08.002
[19] Kong, J., Liu, W., Fu, Y., Zhang, X., Li, Y., Li, J., Sun, L., 2025. Optimization of the process for separating ethylene glycol and 1,2-butanediol using reactive distillation-assisted separation based on a parallel stochastic algorithm framework, Separation and Purification Technology, 354 (2), 128732. https://doi.org/10.1016/j.seppur.2024.128732 
[20] Shuguang Xiang, Lili Wang, Yinglong Wang, Rongshan Bi, Li Xia, Xiaoyan Sun, 2021. Exploration of gradient energy-saving separation processes for ethylene glycol mixtures based on energy, exergy, environment, and economic analyses,  279, 119787. https://doi.org/10.1016/j.seppur.2021.119787
[21] Kiss, A.A. and Suszwalak, DJ.P.C., 2012. Efficient bioethanol dehydration in azeotropic and extractive dividing-wall columns, Proceedings of the 20th International Congress of Chemical and Process CHISA 2012, Prague, Czech Republic, August 25-29.
[22] Valentinyi, N., Marton, G., Toth, A., Haaz, E., Andre, A., Mizsey, P., 2018. Investigation of process alternatives for the separation of ethanol, n-butanol and water ternary mixture, Chemical Engineering Transactions, 69, 607-612. https://doi.org/10.3303/CET1869102
[23] Guerrero-Martin, C.A., Fernández-Ramírez, J.S., Arturo-Calvache, J.E., Milquez-Sanabria, H.A., da Silva Fernandes, F.A., Costa Gomes, V.J., Lima e Silva, W., Valente Duarte, E.D., Guerrero-Martin, L.E., Lucas, E.F., 2023. Exergy Load Distribution Analysis Applied to the Dehydration of Ethanol by Extractive Distillation, Energies, MDPI, 16(8), 1-14. https://doi.org/10.3390/en16083502
[24] García-Ventura, U.M., Barroso-Muñoz, F.O., Hernández, S., 2016. Castro-Montoya, A.J., Experimental study of the production of high purity ethanol using a semi-continuous extractive batch dividing wall distillation column, Chemical Engineering and Processing: Process Intensification, 108, 74–77. https://doi.org/10.1016/j.cep.2016.07.014
[25] Alcántara-Avila, J.R., Kano, M., Hasebe, S., 2012. Environmental and economic optimization of distillation structures to produce anhydrous ethanol, Computer Aided Chemical Engineering, 30, 712-716. https://doi.org/10.1016/B978-0-444-59520-1.50001-4
[26] Shirsat, S.P., Dawande, Sh.D. , Kakade, S.S., 2013. Simulation and optimization of extractive distillation sequence with pre-separator for the ethanol dehydration using n-butyl propionate, Korean Journal of Chemical Engineering, 30, 2163-2169. https://doi.org/10.1007/s11814-013-0175-8
[27] Thein, T.Z., Htway, W.M., Tun, W.E.E., 2018. Dehydration of Aqueous Ethanol Mixtures by Extractive Distillation, International Journal of Science and Engineering Applications, 7(8), 162-165. https://doi.org/10.1021/ba-1972-0115.ch001
[28] Ramírez-Corona, N., Schramm-Flores, A., Reyes-Lombardo, S., Jiménez-Gutiérrez, A., 2019. Effect of ionic liquids as entrainers on the dynamic behavior of ethanol-water extractive columns, BMC Chemical Engineering, 1, 1-11. https://doi.org/10.1186/s42480-019-0023-7
[29] http://www.ddbst.com/en/EED/VLE/VLEindex.php
Chemical Process Design
Volume 5, Issue 1
June 2026
Pages 62-86

Files

Share

How to cite

Statistics