COMPUTER AIDED DESIGN OF DISTILLATION COLUMNS

Abstract

The present investigation pertains to a theoretical study of computer aided design of multicomponent distillation column. Basically it deals with development of design algorithm for the multicomponent distillation column. It also includes the development of design algorithm for the column sizing and valve tray design. Using the simulation method proposed by Thiele-Geddes, a design algorithm has been developed which uses 0-method of convergence for compositions calculation, bubble point method for temperature updation, and constant composition method for vapor flow rate updation. Based on this algorithm a computer program has been developed in 'C' language under 'UNIX' platform. This program has been used for designing a deethaniser column for which feed is a hydrocarbon mixture containing methane, ethane, propane, isobutane and n-butane. The results obtained in the present investigation have been compared with values given in the literature and found to have excellent matching. The CPU time for this deethanizear design has been found to be one second per iteration. This time may increase or decrease depending upon number of components and number of stages. In the second stage of column design, a algorithm has been developed for valve tray design based on Glitsch Inc method. Based on this algorithm a computer program has been developed and design has been obtained for an example problem. The values of tray design parameters obtained in the present investigation have been compared with ,published values and found to have excelent matching.