Recuperação de ácidos orgânicos presentes na vinhaça da fermentação.

Abstract

In face of the growing need for more efficient processes, from an energy, economic and environmental point of view, several process intensification technologies have been evaluated in the last years, especially in separation processes. In addition, the demand for renewable raw materials has grown in order to increase the participation of circular economy in chemical industries. In this context, the main objective of the present work is the development of intensified processes for the recovery of organic acids of industrial interest found in the vinasse produced in the ethanol fermentation. Three scenarios were evaluated; each scenario considers a 1%wt. composition of an organic acid in vinasse. The three acids studied were acetic acid, lactic acid, and succinic acid. For each acid, two processes were developed, one conventional and the other intensified. Each process was optimized considering the total annual cost as the objective function. The results indicate that the recovery of acetic acid using mechanical vapor recompression is the most attractive from the energetic (76.3 GJ/h), economic (TAC of 10.3 MMU$) and environmental (47.1 kt/year of CO2 emitted) perspectives. One of the main conclusions of this study, however, is that process intensification is very attractive to reduce the energy consumption and the environmental penalty of conventional distillation processes.