Document Type : Regular Article

Authors

Department of Chemical Engineering, Faculty of Engineering, Arak University, Arak, 38156-8-8349, Iran

Abstract

The Ethanol-water separation involves a well-known azeotrope that confines the achievement of the ethanol purity to the values higher than 95 wt% using straightforward distillation. Many attempts have been made to identify how it can be possible to produce ultra-pure ethanol (99.95 wt%) for various valuable applications. In practice, minimizing the total cost of the process is of high importance beside having the finished product with utmost purity. As a consequence, finding the best process conditions imposed to apply the simulation and statistical optimization methods in combination. Numerical optimization provides the best trade-offs to achieve the goals. In this research, the separation of the ethanol/water mixture (87 wt%) was simulated using azeotropic distillation in Aspen plus© environment. Indeed, cyclohexane was chosen as an effective azeotrope-former. The UNIQUAC equation was used to describe the phase behavior. The two-column arrangement, in which the first column was used to dehydrate ethanol and the second to recover the entrainer, was applied in this simulation. The effect of important process variables, including the number of the trays in columns and the feed-tray position in each tower on the total capital cost were investigated. Finally, the process variables were optimized via the Response Surface Methodology to minimize the total cost of the process. The results uncovered that the total capital cost would be minimized if the number of the trays in the azeotropic (C1) and recovery (C2) columns were set to 34 and 40, whereas, the feed-tray numbers were adjusted to 19 and 9 respectively.

Keywords

Main Subjects

[1] M. Askari, E. Salehi, and A. Baluchi. "Intensification of hydrogen sulfide absorption by diethanolamine in industrial scale via combined simulation and data-based optimization strategies." Chemical Engineering Research and Design 188 (2022): 545-554.
[2] Baselt, Randall. "Encyclopedia of Toxicology." Journal of Analytical Toxicology 38.7 (2014): 464-464.
[3] Bastidas, P Claudia Marcela, Iván D Gil and G Rodrigueza. "Comparison of the main ethanol dehydration technologies through process simulation." (2009).
[4] Bezerra, Marcos Almeida, et al. "Response surface methodology (RSM) as a tool for optimization in analytical chemistry." Talanta 76.5 (2008): 965-977.
[5] Chang, Jae-Hwa, et al. "Simulation of pervaporation process for ethanol dehydration by using pilot test results." Korean Journal of Chemical Engineering 15.1 (1998): 28-36.
[6] Chien, I-Lung, Huan-Yi Chao and Yao-Pin Teng. "Design and control of a complete heterogeneous azeotropic distillation column system." (2003): 760-765.
[7] Coker, A. Kayode. "Enhanced distillation types." Ludwig's Applied Process Design for Chemical and Petrochemical Plants (2010): 345-371.
[8] Dias De Oliveira, Marcelo E, Burton E Vaughan and Edward J Rykiel. "Ethanol as Fuel: Energy, Carbon Dioxide Balances, and Ecological Footprint." BioScience 55.7 (2005): 593-602.
[9] Duru, Nwabanne and Igbokwe. "Comparative Analysis of Process Flow Configurations for Ethanol Dehydration." International Journal of Scientific & Engineering Research 7.3 (2016).
[10] Eyidogan, Muharrem, et al. "Impact of alcohol–gasoline fuel blends on the performance and combustion characteristics of an SI engine." Fuel 89.10 (2010): 2713-2720.
[11] Fan, Zhiliang. "Consolidated Bioprocessing for Ethanol Production." Biorefineries (2014): 141-160.
[12] Fumero, Yanina, Gabriela Corsano and Jorge M. Montagna. "Simultaneous design and scheduling of a plant for producing ethanol and derivatives." (2011): 1416-1420.
[13] Gil, Iván D., Jorge M. Gómez and Gerardo Rodríguez. "Control of an extractive distillation process to dehydrate ethanol using glycerol as entrainer." Computers & Chemical Engineering 39 (2012): 129-142.
[14] Gudena, Krishna, G. P. Rangaiah and S. Lakshminarayanan. "HiGee Stripper-Membrane System for Decentralized Bioethanol Recovery and Purification." Industrial & Engineering Chemistry Research 52.12 (2013): 4572-4585.
[15] Haydary, J. Chemical Process Design and Simulation: Aspen Plus and Aspen Hysys Applications. Wiley, 2019.
[16] Hosseini, Mehri and Farzam Fotovat. "Optimizing the Design Parameters of a Continuous Electrocoagulation Reactor Used for the Treatment of Oily Wastewater by the Response Surface Methodology." SSRN Electronic Journal (2022).
[17] Junqueira, Tassia L., et al. "Simulation of the Azeotropic Distillation for Anhydrous Bioethanol Production: Study on the Formation of a Second Liquid Phase." (2009): 1143-1148.
[18] Lin, Yan and Shuzo Tanaka. "Ethanol fermentation from biomass resources: current state and prospects." Applied Microbiology and Biotechnology 69.6 (2006): 627-642.
[19] Luyben, W L and I L Chien. Design and Control of Distillation Systems for Separating Azeotropes. Wiley, 2011.
[20] Luyben, William L. "Control of a multiunit heterogeneous azeotropic distillation process." AIChE Journal 52.2 (2006): 623-637.
[21] Luyben, William L. Distillation design and control using Aspen simulation. John Wiley & Sons, 2013.
[22] Luyben, William L. "Economic optimum design of the heterogeneous azeotropic dehydration of ethanol." Industrial and Engineering Chemistry Research 51.50 (2012): 16427-16432.
[23] Miranda, Nahieh Toscano, Rubens Maciel Filho and Maria Regina Wolf Maciel. "Comparison of Complete Extractive and Azeotropic Distillation Processes for Anhydrous Ethanol Production Using Aspen Plus™ Simulator." Chemical Engineering Transactions 80 (2020): 43-48.
[24] Mohapatra, Taraprasad, Sudhansu S. Sahoo and Biranchi N. Padhi. "Analysis, prediction and multi-response optimization of heat transfer characteristics of a three fluid heat exchanger using response surface methodology and desirability function approach." Applied Thermal Engineering 151 (2019): 536-555.
[25] Mortaheb, Hamid Reza and Hitoshi Kosuge. "Simulation and optimization of heterogeneous azeotropic distillation process with a rate-based model." Chemical Engineering and Processing: Process Intensification 43.3 (2004): 317-326.
[26] Pla-Franco, Jordi, et al. "Thermodynamic Analysis and Process Simulation of Ethanol Dehydration via Heterogeneous Azeotropic Distillation." Industrial & Engineering Chemistry Research 53.14 (2014): 6084-6093.
[27] Ryan, Peter J and Michael F Doherty. "Design/optimization of ternary heterogeneous azeotropic distillation sequences." AIChE Journal 35.10 (1989): 1592-1601.
[28] Sarabia and LOrtiz M. "Chapter 12 Response surface methods." (1992): 249-324.
[29] Sarabia, L.A. and M.C. Ortiz. "Response Surface Methodology." Comprehensive Chemometrics (2009): 345-390.
[30] Seader, J D, E J Henley and D K Roper. Separation Process Principles, 3rd Edition. John Wiley Incorporated, 2010.
 [31] Shirsat, Sanjay Pralhad, Shrikant Devidas Dawande and Seema Sudhakar Kakade. "Simulation and optimization of extractive distillation sequence with pre-separator for the ethanol dehydration using n-butyl propionate." Korean Journal of Chemical Engineering 30.12 (2013): 2163-2169.
[32] Vargas Valle, Rosendo, Ma. Guadalupe Lopez Lopez and Enrique Quintero-Marquez. "Control of an azeotropic distillation process for anhydrous ethanol production." CONIELECOMP 2011, 21st International Conference on Electrical Communications and Computers (2011): 88-93.
[33] Vasconcelos, C J G and Maria Regina Wolf-Maciel. "OPTIMISATION , DYNAMICS AND CONTROL OF A COMPLETE AZEOTROPIC DISTILLATION : NEW STRATEGIES AND STABILITY CONSIDERATIONS." (2002).
[34] Widagdo, Soemantri and Warren D Seider. "Journal review. Azeotropic distillation." AIChE Journal 42.1 (1996): 96-130.
[35] X‐Y Zhang, et al. "Sobol Sensitivity Analysis: A Tool to Guide the Development and Evaluation of Systems Pharmacology Models." CPT Pharmacometrics Syst Pharmacol. 4 .2 (2015): 69-79.