Chemical Engineering Research and Design 1 5 9 ( 2 0 2 0 ) 424–438 Contents lists available at ScienceDirect Chemical Engineering Research and Design journal h om epage: www.elsevier.com/locate/cherd New distributed-action control strategy with simultaneous heating and cooling in trays of a pilot-scale diabatic distillation column Geysa Nataly Mello a , Rodrigo Battisti b,d,∗ , Nícolas Soares Urruth c , Ricardo Antonio Francisco Machado d , Cintia Marangoni d a Process Engineering Graduate Program, University of Joinville Region, Santa Catarina 89219-710, Brazil b Federal Institute of Education, Science and Technology of Santa Catarina, Criciúma Campus, 88813-600, Brazil c Departament of Chemical Engineering, Federal University of Santa Catarina, Trindade Campus, 88040-900, Brazil d Chemical Engineering Graduate Program, Federal University of Santa Catarina, Trindade Campus, 88040-900, Brazil a r t i c l e i n f o Article history: Received 8 January 2020 Received in revised form 10 March 2020 Accepted 3 May 2020 Available online 20 May 2020 Keywords: Diabatic distillation Distributed-action control strategy Simultaneous heating and cooling Transient time minimization a b s t r a c t In order to minimize operation transient times, a new distributed control strategy was per- formed in a distillation unit. Acting simultaneously by heating in tray 11 (stripping section), and cooling in tray 3 (rectifying section) of a distillation column, the control strategy was implemented using Aspen Hysys ® with experimental validation. The new distributed con- trol strategy showed a reduction of 0.32 h (19 min) in the transient time when a negative disturbance in the feed temperature was applied (-14 ◦ C), and 0.37 h (22 min) when a pos- itive disturbance in the feed temperature was applied (+14 ◦ C), compared to conventional control. Variations in internal flow rates, as well as temperatures and compositions, were punctual (just where there is control action) and did not affect the steady-state after the disturbance rejection, when compared to conventional control. Distributed-action approach reduced heat amount transferred in the reboiler and reflux flow rate, due to the association with the heat added/removed in trays, evidencing the soft distribution of the control action along the entire column height. Thus, this new distributed control strategy with simulta- neous corrective action between top and bottom of the distillation unit allows a significant reduction in transient times, improving plant productivity. © 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. 1. Introduction Producing with low variability is a crucial task for chemi- cal processing industries to succeed. It is estimated that 95% of separation processes in chemical industries of the world make use of distillation columns, being this the largest energy- consuming unit operation in refineries (Battisti et al., 2020; Enagandula and Riggs, 2006; Pereira and Patel, 2019). Conven- tionally, this process is carried out in stages (or trays) and is characterized by successive evaporations and condensations, ∗ Corresponding author at: Federal Institute of Education, Science and Technology of Santa Catarina, Criciúma Campus, 88813-600, Brazil. E-mail address: rodrigo.battisti@ifsc.edu.br (R. Battisti). which intensifies the energy use, mainly due to the latent heat of vaporization of the mixture components to be sep- arated (Noriler et al., 2008; Zakharov et al., 2018). Besides, conventional distillation columns carry a low thermodynamic efficiency of about 10%, and in some cases, distillation can account for up to 40% of the total energy consumed in chem- ical processing industry (Battisti et al., 2019; Jana, 2017). A well-adjusted distillation unit control system can have a sig- nificant impact on reducing energy consumption, improving product quality, reducing wastes, increasing profitability and https://doi.org/10.1016/j.cherd.2020.05.001 0263-8762/© 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.