Optimum Biorefinery Pathways Selection Using the Integer-Cuts Constraint Method Applied to a MILP Problem

Biorefineries are multi-product facilities that convert biomass into a broad variety of products (energy, biofuels, chemicals, feed, and food). In this paper, a new systematic approach to select and rank different biorefinery conversion pathways is proposed using the Integer-Cut Constraint (ICC) method applied to a MILP problem. In particular, two different statements of the constraints are analyzed. The first step is building a superstructure collecting several biomass conversion models. The ICC method allows different conversion pathways to be evaluated inside the superstructure and ordered according to the objective function values. The key value of a rank of pathways including suboptimal routes allows a fair comparison between alternative biorefinery options and may widen the choice to suboptimal ones. The method is applied to a case study in which various biomass-to-fuel technologies are analyzed to set up a rank of the most promising conversion processes in the current Swiss market.