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BY-NC-ND 3.0 license Open Access Published by De Gruyter Open Access January 29, 2016

Dehydration of Ethanol by PSA Process with Pressure Equalization Step Added

  • Luz Elena Gomar-Madriz , Jaime Saucedo Luna , Medardo Serna-González , Salvador Hernández-Castro and Agustin Jaime Castro-Montoya
From the journal Bioethanol


In this work, the ethanol dehydration production process is carried out using the Mathematical Modeling Pressure Adsorption Process. A new model is suggested, it has two equalization steps, and is compared with the Industrial Pressure Swing Process operating cycle. An analysis of the effects of introducing the pressure equalization step is performed on four main response variables: purity, production, recovery and energy consumption and it is compared with the current cycle configuration operating in the industry. We used Aspen Adsorption for the valuation and simulation of the cyclic PSA process. We analyzed and processed the simulation results in Statgraphics Centurion to obtain optimum operating conditions for the process. This evaluation shows that purity decreases slightly, whereas recovery and production increase. The most important thing is that the energy consumption is reduced. These results clearly show that by modifying the operating cycle schema, optimum operating conditions also change. The optimization of the new cycle was executed considering as variables bed pressure, adsorption time and purging flow. We found that a smaller column is more productive for the equalization cycle than that of a 14m bed, which is optimal in the industrial cycle with a consequent reduction in adsorbent material.


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Received: 2014-12-16
Accepted: 2015-3-31
Published Online: 2016-1-29

© 2016 Luz Elena Gomar-Madriz et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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