ARTICLE IN PRESS JID: JTICE [m5G;December 14, 2017;14:36] Journal of the Taiwan Institute of Chemical Engineers 000 (2017) 1–9 Contents lists available at ScienceDirect Journal of the Taiwan Institute of Chemical Engineers journal homepage: www.elsevier.com/locate/jtice Optimizing ethanol recovery in a spinning cone column Felipe Huerta-Pérez, José Ricardo Pérez-Correa ∗ Department of Chemical and Bioprocess Engineering, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22, Chile a r t i c l e i n f o Article history: Received 28 June 2017 Revised 27 October 2017 Accepted 24 November 2017 Available online xxx Keywords: Wine dealcoholization Beer dealcoholization Distillation Optimization Modeling a b s t r a c t Spinning cone column (SCC) is a separation technology used in the food industry to recover natural aro- mas. It outperforms plate and packed columns given its enhanced mass transfer and capability to process slurries. Limited SCC design and operating guidelines are available, since theoretical studies characterized the SCC hydrodynamics with single components, while experimental studies with complex mixtures do not consider process modeling and optimization. Distillation of a water–ethanol mixture of 14.8% (v/v) in a lab scale SCC was optimized, varying the stripping rate, feed rate and temperature. A first principles model was developed to explain the results in terms of internal variables. Three operating regions were identified. At low stripping rates, the operation was unstable and low performing. At high stripping rates, ethanol recovery and concentration decreased due to a sharp increase in the heat loss that overweighed the mass transfer enhancement. To maximize recoveries, SCC should operate at intermediate-high strip- ping rates, high feed and intermediate temperatures. A high-performance region was found with ethanol recoveries higher than 94% and ethanol concentrations in the distillate over 70%. Our proposed guidelines improve the competitiveness of wine and beer dealcoholization using SCC technology, increasing the yield and marketability of both dealcoholized product and surplus distillate. © 2017 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. 1. Introduction Spinning cone columns (SCC) are direct contact mass transfer devices in the category of thin film liquid evaporators. SCC tech- nology has been widely used in the food industry for the recovery of tea and coffee aromas, dealcoholization of wine and beer, and the extraction of essential oils [1]. The high gas/liquid contact area available in SCC makes them very efficient. In several applications, SCC performs better than plate and packed distillation columns. Their low residence times, small liquid hold-ups as well as their capability to handle viscous materials, solutions with suspended solids, and slurries make them a superior technology [2]. Due to the presence of rotational parts and the complex hydrodynamics occurring inside SCC, the theoretical work has been focused on un- derstanding the fluid dynamics in lab scale SCC operating with one component. The first theoretical work of SCC was the development of a hy- drodynamic model for a one stage column [3]. Later, the same group extended their work developing models for pressure drop, flooding limits and mass transfer inside the column [4,5]. In their analysis, these authors used experimental data from a steam/water ∗ Corresponding author. E-mail addresses: fnhuerta@uc.cl (F. Huerta-Pérez), perez@ing.puc.cl (J.R. Pérez- Correa). system operating at 100 °C and 500 rpm. These hydrodynamic models were validated using Computational Fluid Dynamics (CFD) simulations of a one stage experimental column, using water as working fluid. More recently, Symons developed a model of a coni- cal centrifuge that incorporated a detailed description of boundary conditions [6] and measured the film thickness on a single spin- ning cone [7], finding good agreement between experimental re- sults and model predictions. There are few experimental studies dealing with the impact of operating variables on the performance of multistage SCC process- ing complex mixtures. The effect of solute dilution and rotation speed in rosemary essential oil isolation in a SCC was explored [8] concluding that the highest extraction yield was achieved at low dilution (1/40) and moderate rotation speed (570 rpm). SCC vacuum distillation is widely used as an ethanol removal process in wine and beer dealcoholization. Catarino and Mendes [9] studied a process where beer was first dearomatized by pervaporation, and then dealcoholized in SCC, concluding that SCC distillation under vacuum operation (50 mbar) was an effective process to remove ethanol from beer. Belisario-Sánchez et al. [10] explored the im- pact of the inlet wine flow rate and aromatic extraction percentage (the ratio of the distillate product over the amount of fed wine) of the aroma recovery in dealcoholization of wines. To obtain high ethanol concentrations in the aromatic fraction, the authors found that the raw wine flow rate should be high, and the aromatic ex- traction percentage presented a maximum at 1%. https://doi.org/10.1016/j.jtice.2017.11.030 1876-1070/© 2017 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Please cite this article as: F. Huerta-Pérez, J.R. Pérez-Correa, Optimizing ethanol recovery in a spinning cone column, Journal of the Taiwan Institute of Chemical Engineers (2017), https://doi.org/10.1016/j.jtice.2017.11.030