Fabio R.M. Batista

Computational simulation applied to the investigation of industrial plants for bioethanol distillation

This work aimed to investigate a typical bioethanol distillation process considering an alcoholic wine with 19 components and to validate the simulation results against experimental data collected from a Brazilian sugar mill. The process was investigated in terms of bioethanol alcoholic graduation, ethanol recovery, energy consumption and ethanol loss. Two optimizing approaches were tested: the central composite design (CCD) and the sequential quadratic programming (SQP). Both approaches allowed the optimization of the equipment configuration used nowadays and provided similar optimal conditions. The results showed that the simulation approach was capable of correctly reproducing a real plant of bioethanol distillation and that the optimal conditions guaranteed the bioethanol production according to legislation, with low consumption of steam and high recovery of ethanol. On the other hand, substantial fluctuations in wine composition may require adjustments of operational conditions or the use of specific control loops to prevent an off-specification product.

A Strategy for Controlling Acetaldehyde Content in an Industrial Plant of Bioethanol

Abstract Abstract This work presents a strategy for controlling acetaldehyde content in Brazilian bioethanol, based in simulation results of a typical industrial distillation plant. The major problem of acetaldehyde in bioethanol is that, during the storage period, it can oxidize to acetic acid, increasing fuel acidity above the legislation limit. This work tested, by dynamic simulation, simple loops to control acetaldehyde in bioethanol. The dynamic simulation generated a disturbance in the wine to be distilled by increasing acetaldehyde content, and verified how those loops were able to control the acetaldehyde level in bioethanol. Two different column system configurations were investigated. The first one includes a degassing system and a second one that produces pasteurized alcohol without or with a degassing system. Suggestions for the best control system of acetaldehyde contamination in bioethanol were formulated according to the acetaldehyde level in the wine.