Investigation of an energy-saving double-thermally coupled extractive distillation for separating ternary system benzene/toluene/cyclohexane
Journal
Energy
Journal Volume
186
Date Issued
2019
Author(s)
Abstract
An intensified scheme for the separation of ternary azeotropic system is explored to reduce the energy consumption and recycle important organic solvents. Herein, a novel double-thermally coupled ternary extractive distillation (DTCTED) for separating azeotropic system benzene/toluene/cyclohexane (denoted as B/T/CH) is proposed to achieve energy-saving and emissions reduction. Thermodynamic feasible insights of the B/T/CH using dimethyl formamide as entrainer are firstly analyzed via residue curve maps to find separation constraints. Following that, the proposed intensified scheme is optimized via the in-house multi-objective genetic algorithm software while using total annual cost and CO2 emissions as objective functions. The results show that the total annual cost and CO2 emissions of the proposed intensified DTCTED scheme are significantly reduced by 18.60% and 20.22% compared with the existing single-thermally coupled ternary extractive distillation process. Furthermore, exergy loss and relative volatility are introduced to explore the essence of energy-saving in the proposed DTCTED scheme. © 2019 Elsevier Ltd
Subjects
Energy-saving; Extractive distillation; Residue curve maps; Ternary mixtures; Thermally coupled
Other Subjects
Amides; Benzene; Benzene refining; Carbon dioxide; Distillation; Distilleries; Emission control; Energy utilization; Genetic algorithms; Extractive distillation; Multi-objective genetic algorithm; Objective functions; Relative volatility; Residue curve maps; Separation constraints; Ternary mixtures; Thermally coupled; Energy conservation; algorithm; benzene; distillation; energy efficiency; energy use; extraction method; solvent; thermodynamics; toluene
Type
journal article