Valorization of sugarcane biorefinery residues using supercritical water gasification: A case study and perspectives

The present study evaluates the use of supercritical fluid technology, particularly supercritical water gasification (SCWG), to add value to residues from a sugarcane biorefinery that produces first and second generation ethanol. This case study aims at elucidating how process system engineering tools such as thermal process integration, life cycle analysis, economic evaluation and multi-objective optimization can contribute to minimizing some future challenges of the industrial implementation of supercritical fluid- based technologies, which were discussed in the Workshop on Supercritical Fluids and Energy – SFE’13. In addition, this case study exposes future perspectives in terms of the requirements to further develop this field. The optimized solutions of the evaluated case showed that the SCWG process increases the overall efficiency of the process in terms of energy and carbon fixation. It decreases the CO2 equivalent emissions and it leads to a thermally self-sufficient process. The economic analysis showed a high investment cost but a feasibility of using the current market prices for the produced fuels and electricity.