Application Of MATLAB In Calculating Phase Equilibrium For Methylamine Multicomponent Systems

Vapor-liquid equilibrium (VLE) data is one of the important basic data of developing new products, developing new techniques, reducing energy consumption, treating "three wastes" in chemical industry. The transformation, design and innovation of the equipment used in the separation process including distillation, condensation, evaporation and so on, and the choice of optimal conditions both require the accurate and reliable vapor-liquid equilibrium data. Therefore, vapor-liquid equilibrium data is significantly important in the chemical industry. For the ideal system, it is relatively easy to estimate vapor-liquid equilibrium data. However, most systems focused by enterprise, especially the methylamine system, will deviate from the ideal system and it is difficult to obtain. In addition, methylamine multicomponent systems have the characteristics of low boiling points, easy volatilization, difficult samping, which will lead to certain difficulty in experimental treatment process. Therefore, the VLE data of methylamine multicomponent systems are scarce in the literature.In this paper, MATLAB optimization toolbox and artificial neural network(ANN) were used to study the VLE of the methylamine multicomponent systems. Three groups of binary systems under 101.325kPa, including MMA(1)+H2O(2), DMA(1)+ H2O(2), TMA(1)+H2O(2), three groups of ternary systems under, MMA(1)+ DMA(2)+ H2O(3), MMA(1)+TMA(2)+H2O(3), DMA(1)+ TMA(2)+H2O(3) and a group of quaternary system MMA(1)+DMA(2)+TMA(3)+ H2O(4) were choosed as the study object and MATLAB optimization toolbox was used to calculate Wilson optimum model parameters, bubble-point temperature and vapor composition. The experimental determination VLE data was choosed not only as learning samples of artificial neural network to build the VLE prediction model of the seven groups of research system but also as test samples to test the predictive ability of the network model. BP network model was respectively used to calculate ternary system by binary system and quaternary system by ternary system, at the same time, predict three groups of binary systems VLE data of MMA(1)+ TMA(2), MMA(1)+TMA(2), DMA(1)+TMA(2) from three groups of ternary systems including MMA(1)+ DMA(2)+H2O(3), MMA(1)+TMA(2)+H2O(3), DMA(1)+TMA(2)+H2O(3), and predict the VLE data of methylamine multicomponent binary systems at high pressure by the VLE data under 101.325 kPa, which was compared with the data of Wilson model and literature data.