Separation of a ternary mixture with multiple azeotropes via pressure‐swing distillation

Abstract

BACKGROUND The ternary mixture of tetrahydrofuran (THF), ethanol and water contains multiple azeotropes with the sensitivity to pressure variation. The pressure‐swing distillation (PSD) is a promising method to achieve the system's separation objective since it avoids many potential problems caused by adding a third component. RESULT A variety of separation sequences were synthesized on the ternary diagram, including the sequences of WLEMTH, WLTH EM, THEMWL, THWLEM, EMTHWL and EMWLTH. The optimal design parameters of these sequences were obtained based on the minimum total annual cost (TAC) by using the sequential iterative global optimization algorithm. Furthermore, six kinds of heat integration that improve energy efficiency were implemented for the optimal alternative of EMTHWL. CONCLUSION The results show that the EMTHWL configuration has the lowest TAC, saving 37.84% of the economic cost compared to the THEMWL which has the highest TAC. The partial heat integration among three columns can achieve almost the same reductions in energy requirements and carbon dioxide emissions (44.9%) as the full heat integration among three columns (45.4%). In addition, it is predictable that the partially heat‐integrated alternative compared to other fully heat‐integrated schemes has less undesirable side effects in the aspect of dynamic control. © 2019 Society of Chemical Industry

Application of an Energy-Efficient Process with Reactive Coupling Pressure-Swing Distillation for Recycling Organic Materials from Wastewater

“…The improved energy saving technologies, such as heat integration, 16,17 thermal coupling, 18,19 heat pump, 5,20−24 sidestream, 25 and intermediate reboiler 26 mixture by PSD with various energy-efficient technologies. Wang et al 17 studied ternary mixture separation by PSD with partial heat integration configuration. The results showed that heat integration can well improve the energy efficiency.…”

“…The improved energy saving technologies, such as heat integration, , thermal coupling, , heat pump, ,− side-stream, and intermediate reboiler are used to achieve reduction in energy consumption in the distillation processes. Many researchers have investigated the separation of ternary mixture by PSD with various energy-efficient technologies.…”

“…Many researchers have investigated the separation of ternary mixture by PSD with various energy-efficient technologies. Wang et al studied ternary mixture separation by PSD with partial heat integration configuration. The results showed that heat integration can well improve the energy efficiency.…”

Thermal coupled extractive distillation sequences with three entrainers for the separation of azeotrope isopropyl alcohol + diisopropyl ether

“…Currently, special distillations such as extractive distillation (ED), heterogeneous azeotropic distillation (HAD), pressure‐swing distillation (PSD) and reactive distillation (RD) are adopted to separate such azeotropes. Arifin et al .…”

“…Currently, special distillations such as extractive distillation (ED), 5-8 heterogeneous azeotropic distillation (HAD), [9][10][11][12][13] pressure-swing distillation (PSD) [14][15][16][17] and reactive distillation (RD) [18][19][20][21] are adopted to separate such azeotropes. Arifin et al 22 compared HAD and ED by total annual cost (TAC) to separate the azeotrope IPA + water, and results indicated that ED is more economic than HAD.…”