Process Simulation Of Four Columns Distillation And Analysis Of Column Internal

In this paper,a 300 thousand tons/year methanol production unit with four distillation columns was set as an example of process simulation and analysis through process simulation software PRO/II,to determine the column theoretical plate number,reflux ratio,feed location and other key design parameters of these four columns;inputting the results of the corresponding process simulation into Sulcol software and sizing these four columns as packing column.This design is a successful reference which locate in China.The actual operating parameters are consistent with simulation results and the operation is stable.In recent years,the fixed valve trays(e.g.MVG tray)became more popular in the designs by some foreign licenser's methanol distillation unit and are showing good results.Therefore,the above four columns are resized by Sulcol software with the MVG tray.Comparing the investment cost and operation cost between the original design and the new one:on the one hand inquiry from vendors,to calculate investment cost for the four columns of these two designs;On the other hand,inputting calculated pressure drop for the columns of these two types back into simulation,run and get the corresponding utility consumptions and it's prices,compare and analysis,to get which one has more advantage.This comparison could provide important reference for the future design of middle sized methanol distillation units and other similar ones.