Simplified Methodology for the Design and Optimization of Thermally Coupled Reactive Distillation Systems

Abstract

New intensified schemes have been recently proposed as an attempt to reduce energy requirements and equipment costs in reaction−separation processes. A design methodology for thermally coupled reactive distillation systems is proposed in this work. To design the columns, a method based on the Fenske−Underwood−Gilliland (FUG) equations is proposed and tested. The FUG equations, the mass and energy balances, and the phase equilibrium equations are used to formulate the model of the intensified systems. Such a model is then solved as a nonlinear programming problem; the objective function is the minimization of the heat duty in the column. Biodiesel production through the esterification of oleic acid with supercritical methanol is used as a case study. Results show the feasibility of obtaining designs with low energy requirements by using the proposed methodology. Because of nonconvexities present in the formulation, the estimated interlinking flows for the reactive Petlyuk column might not correspond to a minimum for energy requirements. Nevertheless, the resulting designs not only show low heat duties, with a difference of less than 2% from that minimum, but also have the capacity of achieving the desired conversion and purities.

Synthesis and simulation of a distillation columns system for the propylene glycols mixtures separation

“…The number of theoretical stages, the minimum reflux ratio, and the feed stage estimated position were determined, by preliminary simulations, using the Shortcut column method from the PRO/II 33 simulation software. In this method, the calculation of the preliminary parameters are performed thus: the minimum number of stages by Fenske method, the minimum reflux ratio by Underwood method, the number of theoretical stages by Gilliland correlation, and the estimation of the feed stage by Kirkbride equation 44,45 . The Shortcut column method is a useful tool for preliminary design when it is properly applied.…”

Dynamic Performance of a Complex Distillation System to Separate a Five‐Component Hydrocarbon Mixture

“…The DWCs for ternary separations have been widely studied, and many applications demonstrated that energy consumption can be reduced by 30–50 % compared to conventional columns . Remarkably, these DWC benefits are not limited to ternary separations alone, but they can be present also in azeotropic separations , , extractive distillation , , and reactive distillation , .…”

Design and Control of Dividing-Wall Column for the Synthesis of n-Propyl Propionate by Reactive Distillation

“…Control of an R-DWC is extraordinary more difficult than that of an RD column because of the inner complex structures of the R-DWC . The control of RD columns and DWCs has been studied by many researchers, − but the control of R-DWCs has received less attention, and few studies of it have been reported. However, an R-DWC can be considered as the combination of an RD column and a DWC, so it might be useful to investigate the control of an RD column and a DWC in a study of the control of an R-DWC.…”