Exergy analysis of integrated sceneries to ethanol and other products production from sugar cane

The exergy analysis of six scenarios of integrated schemes for the production of alcohol and other products derived from sugar cane, in order to identify and locate the main sources of irreversibility in these schemes is done. In integrated schemes it is considered sugar cane as the main raw material for the generation of products and co-products. The six scenarios of integration evaluated include the production of sugar, alcohol and first and second generation coproducts such as furfural and lignin, torula yeast obtaining and recovery of CO2. The mass and energy balances for each process were conducted, determining the stream flows involved in the exergetic analysis. Exergy analysis for the integrated scheme was divided into 10 subsystems. Subsystems juice extraction, crystallization and cooking, fermentation and distillation were higher generators exergy losses. Total exergy efficiency of integrated schemes was between 71-80% for scenarios 1 to 5 and 59% for the scenarios that represent not harvest season.