Replacing hexane by ethanol for soybean oil extraction: Modeling, simulation, and techno-economic-environmental analysis

During the transition to a low carbon economy, techno-economic-environmental analyses of industrial processes will have increasing relevance. Within this context, the replacement of hexane by ethanol (either hydrous or anhydrous) as solvent for soybean oil extraction is assessed. Sugarcane bagasse was the fuel for cogeneration of energy. All processes were implemented and simulated in EMSO, Environment for Modeling, Simulation and Optimization, which is an equation-oriented process simulator. For ethanol, four different methods of solvent recovery were evaluated. An economic analysis and a Life Cycle Assessment of the processes were performed. Net Present Value (NPV) and of Global Warming Potential (GWP) were adopted for economic and environmental metrics, respectively. The results showed that all scenarios were economically feasible, with positive NPV, but hexane presented an approximately 10.2% higher NPV then the best-case ethanol process (hydrous). However, the replacement of hexane by ethanol resulted in lower GWP, avoiding the emission of approximately 10,600 ton of CO2eq. per year in an industry that crushes 125 ton per hour of soybean.