Process Simulation And 3E Analysis Of Amination Of Ethanol To Acetonitrile

Acetonitrile,an excellent solvent,has important applications in drug synthesis,petroleum processing,polymer synthesis and other fields.At present,acetonitrile mainly comes from acrylonitrile process,which is used as by-product in acrylonitrile process after purification.However,in the acrylonitrile process,the yield of acetonitrile is only1%～2%.The production capacity of acetonitrile has been greatly limited,which also limits the further development and utilization of acetonitrile.In this study,the process of the amination of ethanol to acetonitrile was studied.The process was analyzed and optimized by comprehensive analysis,multi-objective optimization and heat-integration.In this work,the research on the process of the amination of ethanol to acetonitrile provides a way to solve the problem of acetonitrile production and a reference for the industrial application of the amination of ethanol to acetonitrile.Based on the reaction kinetic data,the operating conditions of reaction temperature and raw material ratio were optimized.The absorption unit was analyzed,and the optimal absorbent flow and distillation column parameters were determined.Through feasibility analysis,the feasibility of separating azeotrope of acetonitrile and water by pressure swing distillation was determined.The simulation of the whole process of amination of ethanol to acetonitrile was established by Aspen Plus software.Economic,thermodynamic,and environmental comprehensive analysis methods are used to improve production performance and energy utilization.Through thermodynamic analysis,it was found that the separation and purification unit and product refining unit had low exergy efficiency,and the total exergy efficiency of the process was 56.43%.The environmental indexes such as Global Warming Potential(GWP)and Cancer human health effects(CHHE)of the process were calculated.Through environmental analysis,it is found that the reaction unit has the highest environmental emission.The results show that there is a contradiction between the economic performance and thermodynamic performance of the process.Taking economy as the objective function,the process optimization was completed based on sequential iterative optimization algorithm.The TAC of the optimal economic scheme was 6.78×10~6$/year,the exergy loss rate was 43.56%.The results show that there is a contradiction between the economic performance and thermodynamic performance of the process.Taking economy and exergy loss rate as objective functions,the multi-objective optimization of the amination of ethanol to acetonitrile process was completed by NSGA-Ⅱalgorithm.The final TAC was 7.21×10~6$/year,and the exergy loss rate was 41.68%.Compared with other schemes,TAC was reduced by 8.6%,and the loss rate was reduced by 4.3%.The multi-objective optimization scheme can achieve a trade-off between economic and thermodynamic efficiency.Compared with the multi-objective optimization scheme,the TAC of the final heat integration process was 6.54×10~6$/year,which was reduced by 9.3%,and the loss rate was 38.59%,which was reduced by 7.4%.