Assessment of the self-sustained energy generation of an integrated first and second generation ethanol production from sugarcane through the characterization of the hydrolysis process residues

Abstract

This paper compares the physico-chemical characterization of bagasse and sugarcane straw used for second-generation ethanol process and the waste produced in a pilot plant. The bagasse was obtained from conventional ethanol process. The cane straw was pruned in a hammer mill and also sent to the second-generation process. Analysis of the bagasse and the residue after hydrolysis indicated that about 64% of the cellulose and 95% of the hemicellulose in the sample was converted to sugars during hydrolysis. Much of the cellulose therefore remains in the final residue together with the lignin. Results for the available energy from the waste generated during the production of first- and second-generation ethanol indicate considerable potential for thermal power generation. For an integrated plant, with conventional ethanol production, second generation ethanol production and a cogeneration system burning sugarcane straw and process residues, energy self-sufficiency is achieved by using only 36% of the cane straw recovery from the field. In this case, 63 kWh is the surplus electricity generated per ton of cane processed.