This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The stu...This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The study particularly emphasizes the production of 99.5 w/w% tetrahydrofuran from the downstream product of 1,4-butanediol synthesis via diethyl maleate. Pro/II simulation software is utilized to explore various system configurations, including sieve trays, valve trays, and packed columns. Material and energy balances are performed to ascertain stream compositions and energy demands. The investigation encompasses the effects of column operating pressure on condenser and reboiler temperatures, as well as the implications of utility streams. A rigorous distillation model is employed to compare valve tray, sieve tray, and random packing (utilizing Norton Super Intalox) column designs by varying the number of trays, reflux ratio, and second distillation column pressure. Heat exchangers are integrated into the model, and their areas and utility flow rates are computed and integrated into the economic assessment. Economic analysis, guided by Net Present Value (NPV) calculations over a 20-year span, drives the selection of the most cost-effective design. Results demonstrate that while all designs are energy-efficient, the packed column system emerges as the most economical choice, offering a comprehensive framework for the separation process. Furthermore, optimal design configurations and operating conditions for both tray and packed column systems are outlined, providing valuable insights for industrial applications.展开更多
The pressure swing distillation(PSD)process for separation of ethyl acetate and ethanol mixture in subplateau region was simulated.The pressure of low-pressure column was set at 0.086 MPa,which is in accordance with t...The pressure swing distillation(PSD)process for separation of ethyl acetate and ethanol mixture in subplateau region was simulated.The pressure of low-pressure column was set at 0.086 MPa,which is in accordance with the atmospheric pressure in the Yunnan-Guizhou region,while the pressure of high-pressure column was determined as 0.304 MPa.Various design parameters,including the plate number,the reflux ratio,and the feeding positions,were optimized,while taking into consideration the total annual cost(TAC).Furthermore,based on the general PSD,the partially heatintegrated pressure swing distillation(PHIPSD)process and the fully heat-integrated pressure swing distillation(FHIPSD)process were also studied.The processes with heat integration showed lower capital cost and lower energy cost,and TACs of the PHIPSD and FHIPSD decreased to 377.21×103$/a and 371.66×103$/a,respectively.Compared with the non-heat integrated process,TACs of the PHIPSD and FHIPSD could be reduced by 27.82%and 28.89%,respectively.The results showed that the FHIPSD process could effectively separate the ethyl acetate-ethanol mixture,and it was more economical and reasonable.This work can provide some technical references for the separation of such azeotropes in the sub-plateau region.展开更多
In the present work,a comparative study of the extractive distillation and pressure swing distillation for methanol-acetonitrile separation is performed for the first time.Different separation alternatives,including t...In the present work,a comparative study of the extractive distillation and pressure swing distillation for methanol-acetonitrile separation is performed for the first time.Different separation alternatives,including the conventional extractive distillation,the extractive distillation with vapor or liquid side-stream,the pressure-swing distillation with or without full heat integration,and the heat-pump assisted pressure-swing distillation are rigorously simulated and optimized based on the minimum total annual cost(TAC)via the sequential iterative strategy.The results show that TAC and CO2 emission of the new extractive distillation with vapor side-stream(Vapor-SED)are similar to those of the extractive distillation with liquid side-stream(Liquid-SED).Furthermore,the Vapor-SED and Liquid-SED can achieve 30.01%and 30.56%reduction in TAC and 23.32%and 23.49%reduction in CO2 emission,respectively,over the most competitive fully heat-integrated PSD configuration.Hence,the extractive distillation with vapor or liquid side-stream appears to be a better option economically and environmentally for the separation of methanol and acetonitrile.展开更多
文摘This paper delves into the comparative study of tray and packed column pressure swing distillation systems, focusing on the separation of a ternary mixture containing ethanol, tetrahydrofuran (THF), and water. The study particularly emphasizes the production of 99.5 w/w% tetrahydrofuran from the downstream product of 1,4-butanediol synthesis via diethyl maleate. Pro/II simulation software is utilized to explore various system configurations, including sieve trays, valve trays, and packed columns. Material and energy balances are performed to ascertain stream compositions and energy demands. The investigation encompasses the effects of column operating pressure on condenser and reboiler temperatures, as well as the implications of utility streams. A rigorous distillation model is employed to compare valve tray, sieve tray, and random packing (utilizing Norton Super Intalox) column designs by varying the number of trays, reflux ratio, and second distillation column pressure. Heat exchangers are integrated into the model, and their areas and utility flow rates are computed and integrated into the economic assessment. Economic analysis, guided by Net Present Value (NPV) calculations over a 20-year span, drives the selection of the most cost-effective design. Results demonstrate that while all designs are energy-efficient, the packed column system emerges as the most economical choice, offering a comprehensive framework for the separation process. Furthermore, optimal design configurations and operating conditions for both tray and packed column systems are outlined, providing valuable insights for industrial applications.
基金This work is financially supported by the Guizhou Province United Fund(Qiankehe J zi LKLS[2013]27)the Guizhou Province Education Department(Qianjiaohe KY zi[2019]137),the Guizhou Province United Fund(Qiankehe LH zi[2015]7608)+2 种基金the Guizhou Solid Waste Recycling Laboratory of Coal Utilization([2011]278)the Guizhou Provincial Education Department’s Scientific and Technological Innovation Team([2017]054)the Academician Workstation of Liupanshui Normal University(Qiankehepingtairencai[2019]5604).
文摘The pressure swing distillation(PSD)process for separation of ethyl acetate and ethanol mixture in subplateau region was simulated.The pressure of low-pressure column was set at 0.086 MPa,which is in accordance with the atmospheric pressure in the Yunnan-Guizhou region,while the pressure of high-pressure column was determined as 0.304 MPa.Various design parameters,including the plate number,the reflux ratio,and the feeding positions,were optimized,while taking into consideration the total annual cost(TAC).Furthermore,based on the general PSD,the partially heatintegrated pressure swing distillation(PHIPSD)process and the fully heat-integrated pressure swing distillation(FHIPSD)process were also studied.The processes with heat integration showed lower capital cost and lower energy cost,and TACs of the PHIPSD and FHIPSD decreased to 377.21×103$/a and 371.66×103$/a,respectively.Compared with the non-heat integrated process,TACs of the PHIPSD and FHIPSD could be reduced by 27.82%and 28.89%,respectively.The results showed that the FHIPSD process could effectively separate the ethyl acetate-ethanol mixture,and it was more economical and reasonable.This work can provide some technical references for the separation of such azeotropes in the sub-plateau region.
文摘In the present work,a comparative study of the extractive distillation and pressure swing distillation for methanol-acetonitrile separation is performed for the first time.Different separation alternatives,including the conventional extractive distillation,the extractive distillation with vapor or liquid side-stream,the pressure-swing distillation with or without full heat integration,and the heat-pump assisted pressure-swing distillation are rigorously simulated and optimized based on the minimum total annual cost(TAC)via the sequential iterative strategy.The results show that TAC and CO2 emission of the new extractive distillation with vapor side-stream(Vapor-SED)are similar to those of the extractive distillation with liquid side-stream(Liquid-SED).Furthermore,the Vapor-SED and Liquid-SED can achieve 30.01%and 30.56%reduction in TAC and 23.32%and 23.49%reduction in CO2 emission,respectively,over the most competitive fully heat-integrated PSD configuration.Hence,the extractive distillation with vapor or liquid side-stream appears to be a better option economically and environmentally for the separation of methanol and acetonitrile.
