1 A COMPARATIVE STUDY BETWEEN THE USE OF REBOILERS AND DIRECT STEAM INJECTION IN DISTILLATION COLUMNS

Ethanol can be obtained by the distillation process. Once there are doubts about the advantages and disadvantages of direct and indirect heating, the aim of this work was to compare three alcohol distillation column projects, using direct steam injection, partial and total reboiler to heat the column. Results based on the case studied showed it is possible to have a stillage quantity reduction of almost 17% and 1.8% of the steam with the use of partial or total reboiler. Based on the quantity of steam decrease observed, it was possible to estimate the payback time of approximately two years for both types of reboilers. Therefore, the partial reboiler proved to be more viable than the total one, since it promotes a separation stage, which can increase the column efficiency and also there is a lower cost than the total reboiler in areas larger than 11,118.57ft2. It can be stated, in both financial and environmental aspects, that it is advantageous to carry out the replacement of direct steam injection with use of reboiler.