Process Simulation And Design Of Gas Fractionation Unit

With the development of chemical industry,the comprehensive utilization of liquefied gas became more and more important.Especially the propylene from refinerys draws.Propylene is an important raw material for producing high valued products which was mainly produced from the gas seperation unit.The function of gas seperation unit is to separate the propylene from the refinery draws with distillation.The gas seperation unit usually uses three columns structure consisted of depropanizer,dethanizer and propylene column.In this paper,Aspen Plus software is used to simulate the whole process,analysing the temperature and pressure distribution and gas-liquid phase load of each column.With the theoretical plate number and the product purity as target variables,the influence of reflux ratio and feed stage position of each column is studied,in order to proposing optimization schemes.In this paper,the column internals arecalculated and designed.Under the guidance of industrial operation experience,reasonable design and calculation of the parameters such as the column diameter,the tray spacing and the weir length are carried out to satisfy design requirements.Under the design condition,the process not only acquire the high efficiency of mass transfer,but also maximize the performance of the distillation column,thus improving product quality and lowering production cost.