Simulation Of A Brand-New Ethyl Acetate Reactive Distillation Process

Ethyl acetate(EA) is one kind of important chemical organic materials, nowdays one of the synthesization processes is via esterification of ethanol(EtOH) and acetic acid(HAc), especially regions abundant in ethanol deposits. Application of reactive distillation technology to improve conversion of esterifiable reactions has been vastly studied in the past years, a brand-new two-column reactive distillation system has been developed, and improved industrialized process of ethyl acetate, accordingly, a new integrated process for ethyl acetate was studied. And feasibility of new process and energy saving was acquired through comparison between two reactive distillation systems, old and new processes using computational simulation.The latest report about research of reactive distillation is the reactive distillation system designed by Yeong tarng tang, it can increase the conversion of reaction, but energy consumption and water composition is higher. The new two-column reactive distillation system was studied, aimed to decrease energy consumption and increase yield of ethyl acetate.At first, physical property of system was discussed due to importance of property parameters, on the basis of binary systems with suitable vapor-liquid and liquid-liquid equilibrium data, a reasonable NRTL model parameter set for calculating liquid activity coefficients has been established by regression system of the commercial simulator Aspen PLUS~@ with excellent prediction of the compositions and temperatures for four azeotropes in this system and phases in liquid-liquid equilibrium; Hayden-O'Connell equation of state was introduced to calculate vapor phase thermodynamic properties due to consideration of vapor association of acetic acid. In order to obtain optimized operating parameters after primary simulation study, optimization analysis on model parameters of reactive distillation was done, including effect of feed location on reboiler duty; effect of HAc feed flow rate and total number of stages on EA composition in top vapor phase;effect of HAc feed flow rate and total number of stages on EA composition in top organic phase; analysis of reflux ratio; we studied the azeotropic distillation process of acetic acid-water system, selecting butyl acetate as entrainer. Ratio of water to entrainer and influence of reflux ratio, theoretical stages, feed locations and temperatures on separation were discussed in detail. Preferred process operation parameter, which had guiding meaning to practical production of distillation process were obtained. Compared with latest reactive distillation process, cooling duty reduced by 57.2%, reboiler duty decreased by 59.2%, mass fraction of water in organic phase decreased to 0.0307, feasibility and superiority of energy saving in new process was proved. Latter, packing column hydraulic analysis was carried out using SULPAK software, results indicated that packings existed in industry satisfied operation of the new process, and analysis study on column diameter and types of packings supplied references to design for internals of distillation column.All-around analysis on presented process via esterification of ethanol and acetic acid was carried out, introducing above brand-new reactive distillation system. A primary schedule of changing process: new reactive distillation system in esterification unit; addition of water-discarded tower; lots of water, resultant in reaction, was discharged in bottom; wastewater recycle column was canceled because of small flow rate of water in top decanter with little ester and ethanol. the new complete process for ethyl acetate was developed. Simulation study showed that process in this thesis decreased energy consumption largely, heightened economic performance of the plant.