Optimization of a Multiproduct Lignocellulosic Biorefinery using a MILP Approximation

Abstract A methodology to reduce the complexity of the process optimization was applied to a multiproduct biorefinery fed by lignocellulosic biomass. A process superstructure was built to consider alternative process pathways to levulinic acid, succinic acid and ethanol. A Mixed Integer Non-Linear Problem was obtained and transformed in a Mixed Integer Linear Problem by means of a discretization procedure of the non-linear variables. Preliminary results for the base case problem yielded a biomass allocation of about 65 % to levulinic acid, 24 % to succinic acid and 11 % to ethanol. A sensitivity analysis highlighted the significant effect of the price of the high value chemicals, levulinic acid and succinic acid, and of the plant size on the optimal biomass allocation.