Simulation And Optimization Of Continuous Refining Process For High Purity Acetonitrile

As separation equipments, rectification columns are widely applied in the separation process, and they play an important role in petrochemical industry. However, petrochemicals paid energy-intensively for their production in rectification process, so the optimization of operation is significant to improve the quality of the products and reduce the energy consumption.This article attempts to take a chemical company directly synthesising acetonitrile as a case, at the base of be familiar with synthesis process of acetonitrile, analysising material properties and the mechanism of distillation, study the process simulation, optimization and control of the separation of acetonitrile ternary system, and try to find a easy way to optimizing the operation. The main content and the results are as follows: At the base of being familiar with acetonitrile synthesis process, analysising material properties and the mechanism of distillation, the process simulation, optimization and control in the separation of acetonitrile ternary system is studied, in order to find a easy way to optimizing the operation. The main content and the results are as follows:1, For the continuous refining process of high purity acetonitrile, this work deeply analyzed the mechanism of distillation, and solved the gas-liquid equilibrium equation of the ternary systems (acetonitrile-water- methanol), and employed the NRTL model to get the thermodynamic parameters of material. This method was applied to the simulation of continuous refining process of acetonitrile, the simulation results were close to practical data. This result confirmed that the combination of advanced simulation system, technology and experiences can forecast the variation of operating parameters in the rectifying process.2, The phase diagram of ternary vapor-liquid equilibrium was applied to analysis the triple azeotropic system in the distillation of acetonitrile. This work investigates the effect of stage, pressure, out stream and reflux ratio on the properties of the concentration of acetonitrile and energy consumption during distillation process, the most appropriate operation parameters were determined by the feasible control region of optimize operation. 3, The optimal parameters were applied to put forward control scheme in the production in chemical factory which had some problems such as the supplement of steam was unstable, especially existed larger time-delay which was nonlinear and time-variable. According to the feedback from production, the concentration and recovery of acetonitrile was 99.9% and 90%, respectively, while reduce energy consumption up to 30%.