Multiobjective optimization of the supply chain for the production of biomass-based fuels and high-value added products in Mexico

Abstract

Due to the growing concern about the increase in the concentration of greenhouse gases in the atmosphere, as well as the depletion of oil reserves, biofuels have become increasingly important. Human activity, mainly in the industrial and transportation sectors, is one of the main causes of the above scenario. Bioethanol and biobutanol have emerged as possible solutions to this problem, however, their production is not economically competitive. Therefore, in addition to biofuel production, the generation of high value-added products in a biorefinery scheme is mandatory to improve the economic potential of the biomass-based industry. Mexico is a country with a high agricultural production, which implies a high production of agricultural waste. Therefore, this work proposes the development of a mathematical model for the supply chain of biofuels and bioproducts production. This model is a multi-objective optimization problem through generalized disjunctive programming. The GDP model is relaxed and solved in its equivalent mixed integer linear programming form using GAMS software. The model analyzes the production of bioethanol and/or biobutanol to satisfy at least 10% of the gasoline demand in the country, as well as the production of high value-added products; considering economic, environmental, economic and social objectives. Pareto-optimal solutions were obtained using the ε constraint method and selecting the best option by the Pythagorean theorem of the Eucladian distance. According to the results, biobutanol production is the process that maintains the greatest compromise between the four objective functions, achieving a balance. On the other hand, bioethanol production is only feasible if the water footprint is disregarded, as high values are obtained, which leads to a problem of water distribution to carry out the process.